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Bibliography on: Origin of Multicellular Eukaryotes

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ESP: PubMed Auto Bibliography 02 Dec 2023 at 01:49 Created: 

Origin of Multicellular Eukaryotes

Created with PubMed® Query: ( (origin OR evolution) AND (eukaryotes OR eukaryota) AND (multicelluarity OR multicellular) NOT 33634751[PMID] ) NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)


RevDate: 2023-12-01

Mulvey H, L Dolan (2023)

RHO of plant signaling was established early in streptophyte evolution.

Current biology : CB pii:S0960-9822(23)01520-8 [Epub ahead of print].

The algal ancestors of land plants underwent a transition from a unicellular to a multicellular body plan.[1] This transition likely took place early in streptophyte evolution, sometime after the divergence of the Chlorokybophyceae/Mesostigmatophyceae lineage, but before the divergence of the Klebsormidiophyceae lineage.[2] How this transition was brought about is unknown; however, it was likely facilitated by the evolution of novel mechanisms to spatially regulate morphogenesis. In land plants, RHO of plant (ROP) signaling plays a conserved role in regulating polarized cell growth and cell division orientation to orchestrate morphogenesis.[3][,][4][,][5][,][6][,][7][,][8] ROP constitutes a plant-specific subfamily of the RHO GTPases, which are more widely conserved throughout eukaryotes.[9][,][10] Although the RHO family originated in early eukaryotes,[11][,][12] how and when the ROP subfamily originated had remained elusive. Here, we demonstrate that ROP signaling was established early in the streptophyte lineage, sometime after the divergence of the Chlorokybophyceae/Mesostigmatophyceae lineage, but before the divergence of the Klebsormidiophyceae lineage. This period corresponds to when the unicellular-to-multicellular transition likely took place in the streptophytes. In addition to being critical for the complex morphogenesis of extant land plants, we speculate that ROP signaling contributed to morphological evolution in early streptophytes.

RevDate: 2023-11-29
CmpDate: 2023-11-29

Kulkarni M, JM Hardwick (2023)

Programmed Cell Death in Unicellular Versus Multicellular Organisms.

Annual review of genetics, 57:435-459.

Programmed cell death (self-induced) is intrinsic to all cellular life forms, including unicellular organisms. However, cell death research has focused on animal models to understand cancer, degenerative disorders, and developmental processes. Recently delineated suicidal death mechanisms in bacteria and fungi have revealed ancient origins of animal cell death that are intertwined with immune mechanisms, allaying earlier doubts that self-inflicted cell death pathways exist in microorganisms. Approximately 20 mammalian death pathways have been partially characterized over the last 35 years. By contrast, more than 100 death mechanisms have been identified in bacteria and a few fungi in recent years. However, cell death is nearly unstudied in most human pathogenic microbes that cause major public health burdens. Here, we consider how the current understanding of programmed cell death arose through animal studies and how recently uncovered microbial cell death mechanisms in fungi and bacteria resemble and differ from mechanisms of mammalian cell death.

RevDate: 2023-11-28

Bingham EP, WC Ratcliff (2023)

A non-adaptive explanation for macroevolutionary patterns in the evolution of complex multicellularity.

bioRxiv : the preprint server for biology pii:2023.11.11.566713.

"Complex multicellularity", conventionally defined as large organisms with many specialized cell types, has evolved five times independently in eukaryotes, but never within prokaryotes. A number hypotheses have been proposed to explain this phenomenon, most of which posit that eukaryotes evolved key traits (e . g ., dynamic cytoskeletons, alternative mechanisms of gene regulation, or subcellular compartments) which were a necessary prerequisite for the evolution of complex multicellularity. Here we propose an alternative, non-adaptive hypothesis for this broad macroevolutionary pattern. By binning cells into groups with finite genetic bottlenecks between generations, the evolution of multicellularity greatly reduces the effective population size (Ne) of cellular populations, increasing the role of genetic drift in evolutionary change. While both prokaryotes and eukaryotes experience this phenomenon, they have opposite responses to drift: mutational biases in eukaryotes tend to drive genomic expansion, providing additional raw genetic material for subsequent multicellular innovation, while prokaryotes generally face genomic erosion. These effects become more severe as organisms evolve larger size and more stringent genetic bottlenecks between generations- both of which are hallmarks of complex multicellularity. Taken together, we hypothesize that it is these idiosyncratic lineagespecific mutational biases, rather than cell-biological innovations within eukaryotes, that underpins the long-term divergent evolution of complex multicellularity across the tree of life.

RevDate: 2023-11-27
CmpDate: 2023-11-27

Toch K, Buczek M, MK Labocha (2023)

Genetic Interactions in Various Environmental Conditions in Caenorhabditis elegans.

Genes, 14(11):.

Although it is well known that epistasis plays an important role in many evolutionary processes (e.g., speciation, evolution of sex), our knowledge on the frequency and prevalent sign of epistatic interactions is mainly limited to unicellular organisms or cell cultures of multicellular organisms. This is even more pronounced in regard to how the environment can influence genetic interactions. To broaden our knowledge in that respect we studied gene-gene interactions in a whole multicellular organism, Caenorhabditis elegans. We screened over one thousand gene interactions, each one in standard laboratory conditions, and under three different stressors: heat shock, oxidative stress, and genotoxic stress. Depending on the condition, between 7% and 22% of gene pairs showed significant genetic interactions and an overall sign of epistasis changed depending on the condition. Sign epistasis was quite common, but reciprocal sign epistasis was extremally rare. One interaction was common to all conditions, whereas 78% of interactions were specific to only one environment. Although epistatic interactions are quite common, their impact on evolutionary processes will strongly depend on environmental factors.

RevDate: 2023-11-27
CmpDate: 2023-11-27

Spradling AC (2024)

The Ancient Origin and Function of Germline Cysts.

Results and problems in cell differentiation, 71:3-21.

Gamete production in most animal species is initiated within an evolutionarily ancient multicellular germline structure, the germline cyst, whose interconnected premeiotic cells synchronously develop from a single progenitor arising just downstream from a stem cell. Cysts in mice, Drosophila, and many other animals protect developing sperm, while in females, cysts generate nurse cells that guard sister oocytes from transposons (TEs) and help them grow and build a Balbiani body. However, the origin and extreme evolutionary conservation of germline cysts remains a mystery. We suggest that cysts arose in ancestral animals like Hydra and Planaria whose multipotent somatic and germline stem cells (neoblasts) express genes conserved in all animal germ cells and frequently begin differentiation in cysts. A syncytial state is proposed to help multipotent stem cell chromatin transition to an epigenetic state with heterochromatic domains suitable for TE repression and specialized function. Most modern animals now lack neoblasts but have retained stem cells and cysts in their early germlines, which continue to function using this ancient epigenetic strategy.

RevDate: 2023-11-27

Goehring L, Huang TT, DJ Smith (2023)

Transcription-Replication Conflicts as a Source of Genome Instability.

Annual review of genetics, 57:157-179.

Transcription and replication both require large macromolecular complexes to act on a DNA template, yet these machineries cannot simultaneously act on the same DNA sequence. Conflicts between the replication and transcription machineries (transcription-replication conflicts, or TRCs) are widespread in both prokaryotes and eukaryotes and have the capacity to both cause DNA damage and compromise complete, faithful replication of the genome. This review will highlight recent studies investigating the genomic locations of TRCs and the mechanisms by which they may be prevented, mitigated, or resolved. We address work from both model organisms and mammalian systems but predominantly focus on multicellular eukaryotes owing to the additional complexities inherent in the coordination of replication and transcription in the context of cell type-specific gene expression and higher-order chromatin organization.

RevDate: 2023-11-23
CmpDate: 2023-11-23

Jin H, Zhang W, Liu H, et al (2023)

Genome-wide identification and characteristic analysis of ETS gene family in blood clam Tegillarca granosa.

BMC genomics, 24(1):700.

BACKGROUND: ETS transcription factors, known as the E26 transformation-specific factors, assume a critical role in the regulation of various vital biological processes in animals, including cell differentiation, the cell cycle, and cell apoptosis. However, their characterization in mollusks is currently lacking.

RESULTS: The current study focused on a comprehensive analysis of the ETS genes in blood clam Tegillarca granosa and other mollusk genomes. Our phylogenetic analysis revealed the absence of the SPI and ETV subfamilies in mollusks compared to humans. Additionally, several ETS genes in mollusks were found to lack the PNT domain, potentially resulting in a diminished ability of ETS proteins to bind target genes. Interestingly, the bivalve ETS1 genes exhibited significantly high expression levels during the multicellular proliferation stage and in gill tissues. Furthermore, qRT-PCR results showed that Tg-ETS-14 (ETS1) is upregulated in the high total hemocyte counts (THC) population of T. granosa, suggesting it plays a significant role in stimulating hemocyte proliferation.

CONCLUSION: Our study significantly contributes to the comprehension of the evolutionary aspects concerning the ETS gene family, while also providing valuable insights into its role in fostering hemocyte proliferation across mollusks.

RevDate: 2023-11-22

Nicolas E, Simion P, Guérineau M, et al (2023)

Horizontal acquisition of a DNA ligase improves DNA damage tolerance in eukaryotes.

Nature communications, 14(1):7638.

Bdelloid rotifers are part of the restricted circle of multicellular animals that can withstand a wide range of genotoxic stresses at any stage of their life cycle. In this study, bdelloid rotifer Adineta vaga is used as a model to decipher the molecular basis of their extreme tolerance. Proteomic analysis shows that a specific DNA ligase, different from those usually involved in DNA repair in eukaryotes, is strongly over-represented upon ionizing radiation. A phylogenetic analysis reveals its orthology to prokaryotic DNA ligase E, and its horizontal acquisition by bdelloid rotifers and plausibly other eukaryotes. The fungus Mortierella verticillata, having a single copy of this DNA Ligase E homolog, also exhibits an increased radiation tolerance with an over-expression of this DNA ligase E following X-ray exposure. We also provide evidence that A. vaga ligase E is a major contributor of DNA breaks ligation activity, which is a common step of all important DNA repair pathways. Consistently, its heterologous expression in human cell lines significantly improves their radio-tolerance. Overall, this study highlights the potential of horizontal gene transfers in eukaryotes, and their contribution to the adaptation to extreme conditions.

RevDate: 2023-11-15
CmpDate: 2023-11-15

Liu Y, Liu Y, Chen S, et al (2023)

Prenatal exposure to acetaminophen at different doses, courses and time causes testicular dysplasia in offspring mice and its mechanism.

Chemosphere, 345:140496.

Epidemiological investigation suggested that the use of acetaminophen during pregnancy may cause offspring testicular dysplasia, but no systematic study has been conducted. In this study, Kunming mice were given acetaminophen at different doses (100/200/400 mg/kg.d), courses (single/multiple), time (second/third trimester) during pregnancy. Fetal blood and testes were collected on gestaional day 18 for detection. The results indicated abnormal testicular development in the PAcE (prenatal acetaminophen exposure) groups. The maximum diameter/cross-sectional area decreased, the interstitial space widened, and decreased proliferation/increased apoptosis were observed, especially in the high-dose, multi-course and second-trimester groups. Meanwhile, the serum testosterone level decreased in PAcE groups, and the steroid synthesis function in Leydig cells, Sertoli and spermatogenic cell function were inhibited, it was more significant in high-dose, multi-course and second-trimester groups. Furthermore, Wnt signal pathway was activated but Notch signal pathway was inhibited in the PAcE groups. Finally, in vitro experiment, acetaminophen could inhibit spermatogonial cell proliferation, enhance apoptosis, and change Wnt/Notch signal pathway. In conclusion, this study confirmed that PAcE can change fetal testicular development in a dose, course and time-dependent manner, and found that multicellular function impaired. This study provides theoretical and experimental basis for systematically elucidating the developmental toxicity of acetaminophen in testis.

RevDate: 2023-11-14
CmpDate: 2023-11-14

Fulda FC (2023)

Agential autonomy and biological individuality.

Evolution & development, 25(6):353-370.

What is a biological individual? How are biological individuals individuated? How can we tell how many individuals there are in a given assemblage of biological entities? The individuation and differentiation of biological individuals are central to the scientific understanding of living beings. I propose a novel criterion of biological individuality according to which biological individuals are autonomous agents. First, I articulate an ecological-dynamical account of natural agency according to which, agency is the gross dynamical capacity of a goal-directed system to bias its repertoire to respond to its conditions as affordances. Then, I argue that agents or agential dynamical systems can be agentially dependent on, or agentially autonomous from, other agents and that this agential dependence/autonomy can be symmetrical or asymmetrical, strong or weak. Biological individuals, I propose, are all and only those agential dynamical systems that are strongly agentially autonomous. So, to determine how many individuals there are in a given multiagent aggregate, such as multicellular organism, a colony, symbiosis, or a swarm, we first have to identify how many agential dynamical systems there are, and then what their relations of agential dependence/autonomy are. I argue that this criterion is adequate to the extent that it vindicates the paradigmatic cases, and explains why the paradigmatic cases are paradigmatic, and why the problematic cases are problematic. Finally, I argue for the importance of distinguishing between agential and causal dependence and show the relevance of agential autonomy for understanding the explanatory structure of evolutionary developmental biology.

RevDate: 2023-11-13
CmpDate: 2023-11-13

Wang X, Xu X, Z Wang (2023)

The Post-Translational Role of UFMylation in Physiology and Disease.

Cells, 12(21): pii:cells12212543.

Ubiquitin-fold modifier 1 (UFM1) is a newly identified ubiquitin-like protein that has been conserved during the evolution of multicellular organisms. In a similar manner to ubiquitin, UFM1 can become covalently linked to the lysine residue of a substrate via a dedicated enzymatic cascade. Although a limited number of substrates have been identified so far, UFM1 modification (UFMylation) has been demonstrated to play a vital role in a variety of cellular activities, including mammalian development, ribosome biogenesis, the DNA damage response, endoplasmic reticulum stress responses, immune responses, and tumorigenesis. In this review, we summarize what is known about the UFM1 enzymatic cascade and its biological functions, and discuss its recently identified substrates. We also explore the pathological role of UFMylation in human disease and the corresponding potential therapeutic targets and strategies.

RevDate: 2023-11-13
CmpDate: 2023-11-13

Zhang Z, Huo W, Wang X, et al (2023)

Origin, evolution, and diversification of the wall-associated kinase gene family in plants.

Plant cell reports, 42(12):1891-1906.

The study of the origin, evolution, and diversification of the wall-associated kinase gene family in plants facilitates their functional investigations in the future. Wall-associated kinases (WAKs) make up one subfamily of receptor-like kinases (RLKs), and function directly in plant cell elongation and responses to biotic and abiotic stresses. The biological functions of WAKs have been extensively characterized in angiosperms; however, the origin and evolutionary history of the WAK family in green plants remain unclear. Here, we performed a comprehensive analysis of the WAK family to reveal its origin, evolution, and diversification in green plants. In total, 1061 WAK genes were identified in 37 species from unicellular algae to multicellular plants, and the results showed that WAK genes probably originated before bryophyte differentiation and were widely distributed in land plants, especially angiosperms. The phylogeny indicated that the land plant WAKs gave rise to five clades and underwent lineage-specific expansion after species differentiation. Cis-acting elements and expression patterns analyses of WAK genes in Arabidopsis and rice demonstrated the functional diversity of WAK genes in these two species. Many gene gains and losses have occurred in angiosperms, leading to an increase in the number of gene copies. The evolutionary trajectory of the WAK family during polyploidization was uncovered using Gossypium species. Our results provide insights into the evolution of WAK genes in green plants, facilitating their functional investigations in the future.

RevDate: 2023-11-07
CmpDate: 2023-11-07

Fung L, Konkol A, Ishikawa T, et al (2023)

Swimming, Feeding, and Inversion of Multicellular Choanoflagellate Sheets.

Physical review letters, 131(16):168401.

The recent discovery of the striking sheetlike multicellular choanoflagellate species Choanoeca flexa that dynamically interconverts between two hemispherical forms of opposite orientation raises fundamental questions in cell and evolutionary biology, as choanoflagellates are the closest living relatives of animals. It similarly motivates questions in fluid and solid mechanics concerning the differential swimming speeds in the two states and the mechanism of curvature inversion triggered by changes in the geometry of microvilli emanating from each cell. Here we develop fluid dynamical and mechanical models to address these observations and show that they capture the main features of the swimming, feeding, and inversion of C. flexa colonies, which can be viewed as active, shape-shifting polymerized membranes.

RevDate: 2023-11-07
CmpDate: 2023-11-07

Lamża Ł (2023)

Diversity of 'simple' multicellular eukaryotes: 45 independent cases and six types of multicellularity.

Biological reviews of the Cambridge Philosophical Society, 98(6):2188-2209.

Multicellularity evolved multiple times in the history of life, with most reviewers agreeing that it appeared at least 20 times in eukaryotes. However, a specific list of multicellular eukaryotes with clear criteria for inclusion has not yet been published. Herein, an updated critical review of eukaryotic multicellularity is presented, based on current understanding of eukaryotic phylogeny and new discoveries in microbiology, phycology and mycology. As a result, 45 independent multicellular lineages are identified that fall into six distinct types. Functional criteria, as distinct from a purely topological definition of a cell, are introduced to bring uniformity and clarity to the existing definitions of terms such as colony, multicellularity, thallus or plasmodium. The category of clonal multicellularity is expanded to include: (i) septated multinucleated thalli found in Pseudofungi and early-branching Fungi such as Chytridiomycota and Blastocladiomycota; and (ii) multicellular reproductive structures formed by plasmotomy in intracellular parasites such as Phytomyxea. Furthermore, (iii) endogeneous budding, as found in Paramyxida, is described as a form of multicellularity. The best-known case of clonal multicellularity, i.e. (iv) non-separation of cells after cell division, as known from Metazoa and Ochrophyta, is also discussed. The category of aggregative multicellularity is expanded to include not only (v) pseudoplasmodial forms, such a sorocarp-forming Acrasida, but also (vi) meroplasmodial organisms, such as members of Variosea or Filoreta. A common set of topological, geometric, genetic and life-cycle criteria are presented that form a coherent, philosophically sound framework for discussing multicellularity. A possibility of a seventh type of multicellularity is discussed, that of multi-species superorganisms formed by protists with obligatory bacterial symbionts, such as some members of Oxymonada or Parabasalia. Its inclusion is dependent on the philosophical stance taken towards the concepts of individuality and organism in biology. Taxa that merit special attention are identified, such as colonial Centrohelea, and a new speculative form of multicellularity, possibly present in some reticulopodial amoebae, is briefly described. Because of insufficient phylogenetic and morphological data, not all lineages could be unequivocally identified, and the true total number of all multicellular eukaryotic lineages is therefore higher, likely close to a hundred.

RevDate: 2023-11-06

Dupouy G, Cashell R, Brychkova G, et al (2023)

PICKLE RELATED 2 is a Neofunctionalized Gene Duplicate Under Positive Selection With Antagonistic Effects to the Ancestral PICKLE Gene on the Seed Transcriptome.

Genome biology and evolution, 15(11):.

The evolution and diversification of proteins capable of remodeling domains has been critical for transcriptional reprogramming during cell fate determination in multicellular eukaryotes. Chromatin remodeling proteins of the CHD3 family have been shown to have important and antagonistic impacts on seed development in the model plant, Arabidopsis thaliana, yet the basis of this functional divergence remains unknown. In this study, we demonstrate that genes encoding the CHD3 proteins PICKLE (PKL) and PICKLE-RELATED 2 (PKR2) originated from a duplication event during the diversification of crown Brassicaceae, and that these homologs have undergone distinct evolutionary trajectories since this duplication, with PKR2 fast evolving under positive selection, while PKL is subject to purifying selection. We find that the rapid evolution of PKR2 under positive selection reduces the encoded protein's intrinsic disorder, possibly suggesting a tertiary structure configuration which differs from that of PKL. Our whole genome transcriptome analysis in seeds of pkr2 and pkl mutants reveals that they act antagonistically on the expression of specific sets of genes, providing a basis for their differing roles in seed development. Our results provide insights into how gene duplication and neofunctionalization can lead to differing and antagonistic selective pressures on transcriptomes during plant reproduction, as well as on the evolutionary diversification of the CHD3 family within seed plants.

RevDate: 2023-11-01
CmpDate: 2023-11-01

Balasubramanian RN, Gao M, J Umen (2023)

Identification of cell-type specific alternative transcripts in the multicellular alga Volvox carteri.

BMC genomics, 24(1):654.

BACKGROUND: Cell type specialization is a hallmark of complex multicellular organisms and is usually established through implementation of cell-type-specific gene expression programs. The multicellular green alga Volvox carteri has just two cell types, germ and soma, that have previously been shown to have very different transcriptome compositions which match their specialized roles. Here we interrogated another potential mechanism for differentiation in V. carteri, cell type specific alternative transcript isoforms (CTSAI).

METHODS: We used pre-existing predictions of alternative transcripts and de novo transcript assembly with HISAT2 and Ballgown software to compile a list of loci with two or more transcript isoforms, identified a small subset that were candidates for CTSAI, and manually curated this subset of genes to remove false positives. We experimentally verified three candidates using semi-quantitative RT-PCR to assess relative isoform abundance in each cell type.

RESULTS: Of the 1978 loci with two or more predicted transcript isoforms 67 of these also showed cell type isoform expression biases. After curation 15 strong candidates for CTSAI were identified, three of which were experimentally verified, and their predicted gene product functions were evaluated in light of potential cell type specific roles. A comparison of genes with predicted alternative splicing from Chlamydomonas reinhardtii, a unicellular relative of V. carteri, identified little overlap between ortholog pairs with alternative splicing in both species. Finally, we interrogated cell type expression patterns of 126 V. carteri predicted RNA binding protein (RBP) encoding genes and found 40 that showed either somatic or germ cell expression bias. These RBPs are potential mediators of CTSAI in V. carteri and suggest possible pre-adaptation for cell type specific RNA processing and a potential path for generating CTSAI in the early ancestors of metazoans and plants.

CONCLUSIONS: We predicted numerous instances of alternative transcript isoforms in Volvox, only a small subset of which showed cell type specific isoform expression bias. However, the validated examples of CTSAI supported existing hypotheses about cell type specialization in V. carteri, and also suggested new hypotheses about mechanisms of functional specialization for their gene products. Our data imply that CTSAI operates as a minor but important component of V. carteri cellular differentiation and could be used as a model for how alternative isoforms emerge and co-evolve with cell type specialization.

RevDate: 2023-10-30
CmpDate: 2023-10-30

Ashouri A, Zhang C, F Gaiti (2023)

Decoding Cancer Evolution: Integrating Genetic and Non-Genetic Insights.

Genes, 14(10):.

The development of cancer begins with cells transitioning from their multicellular nature to a state akin to unicellular organisms. This shift leads to a breakdown in the crucial regulators inherent to multicellularity, resulting in the emergence of diverse cancer cell subpopulations that have enhanced adaptability. The presence of different cell subpopulations within a tumour, known as intratumoural heterogeneity (ITH), poses challenges for cancer treatment. In this review, we delve into the dynamics of the shift from multicellularity to unicellularity during cancer onset and progression. We highlight the role of genetic and non-genetic factors, as well as tumour microenvironment, in promoting ITH and cancer evolution. Additionally, we shed light on the latest advancements in omics technologies that allow for in-depth analysis of tumours at the single-cell level and their spatial organization within the tissue. Obtaining such detailed information is crucial for deepening our understanding of the diverse evolutionary paths of cancer, allowing for the development of effective therapies targeting the key drivers of cancer evolution.

RevDate: 2023-10-30
CmpDate: 2023-10-30

Pentz JT, MacGillivray K, DuBose JG, et al (2023)

Evolutionary consequences of nascent multicellular life cycles.

eLife, 12:.

A key step in the evolutionary transition to multicellularity is the origin of multicellular groups as biological individuals capable of adaptation. Comparative work, supported by theory, suggests clonal development should facilitate this transition, although this hypothesis has never been tested in a single model system. We evolved 20 replicate populations of otherwise isogenic clonally reproducing 'snowflake' yeast (Δace2/∆ace2) and aggregative 'floc' yeast (GAL1p::FLO1 /GAL1p::FLO1) with daily selection for rapid growth in liquid media, which favors faster cell division, followed by selection for rapid sedimentation, which favors larger multicellular groups. While both genotypes adapted to this regime, growing faster and having higher survival during the group-selection phase, there was a stark difference in evolutionary dynamics. Aggregative floc yeast obtained nearly all their increased fitness from faster growth, not improved group survival; indicating that selection acted primarily at the level of cells. In contrast, clonal snowflake yeast mainly benefited from higher group-dependent fitness, indicating a shift in the level of Darwinian individuality from cells to groups. Through genome sequencing and mathematical modeling, we show that the genetic bottlenecks in a clonal life cycle also drive much higher rates of genetic drift-a result with complex implications for this evolutionary transition. Our results highlight the central role that early multicellular life cycles play in the process of multicellular adaptation.

RevDate: 2023-10-23
CmpDate: 2023-10-23

Clark JW, Hetherington AJ, Morris JL, et al (2023)

Evolution of phenotypic disparity in the plant kingdom.

Nature plants, 9(10):1618-1626.

The plant kingdom exhibits diverse bodyplans, from single-celled algae to complex multicellular land plants, but it is unclear how this phenotypic disparity was achieved. Here we show that the living divisions comprise discrete clusters within morphospace, separated largely by reproductive innovations, the extinction of evolutionary intermediates and lineage-specific evolution. Phenotypic complexity correlates not with disparity but with ploidy history, reflecting the role of genome duplication in plant macroevolution. Overall, the plant kingdom exhibits a pattern of episodically increasing disparity throughout its evolutionary history that mirrors the evolutionary floras and reflects ecological expansion facilitated by reproductive innovations. This pattern also parallels that seen in the animal and fungal kingdoms, suggesting a general pattern for the evolution of multicellular bodyplans.

RevDate: 2023-10-23
CmpDate: 2023-10-23

Tsai HH, Wang J, Geldner N, et al (2023)

Spatiotemporal control of root immune responses during microbial colonization.

Current opinion in plant biology, 74:102369.

The entire evolutionary trajectory of plants towards large and complex multi-cellular organisms has been accompanied by incessant interactions with omnipresent unicellular microbes. This led to the evolution of highly complex microbial communities, whose members display the entire spectrum of pathogenic to mutualistic behaviors. Plant roots are dynamic, fractally growing organs and even small Arabidopsis roots harbor millions of individual microbes of diverse taxa. It is evident that microbes at different positions on a root surface could experience fundamentally different environments, which, moreover, rapidly change over time. Differences in spatial scales between microbes and roots compares to humans and the cities they inhabit. Such considerations make it evident that mechanisms of root-microbe interactions can only be understood if analyzed at relevant spatial and temporal scales. This review attempts to provide an overview of the rapid recent progress that has been made in mapping and manipulating plant damage and immune responses at cellular resolution, as well as in visualizing bacterial communities and their transcriptional activities. We further discuss the impact that such approaches will have for a more predictive understanding of root-microbe interactions.

RevDate: 2023-10-22
CmpDate: 2023-10-22

Arenzon JJ, L Peliti (2023)

Emergent cooperative behavior in transient compartments.

Physical review. E, 108(3-1):034409.

We introduce a minimal model of multilevel selection on structured populations, considering the interplay between game theory and population dynamics. Through a bottleneck process, finite groups are formed with cooperators and defectors sampled from an infinite pool. After the fragmentation, these transient compartments grow until the maximal number of individuals per compartment is attained. Eventually, all compartments are merged and well mixed, and the whole process is repeated. We show that cooperators, even if interacting only through mean-field intragroup interactions that favor defectors, may perform well because of the intergroup competition and the size diversity among the compartments. These cycles of isolation and coalescence may therefore be important in maintaining diversity among different species or strategies and may help to understand the underlying mechanisms of the scaffolding processes in the transition to multicellularity.

RevDate: 2023-10-22
CmpDate: 2023-10-22

Horinouchi Y, T Togashi (2023)

Unicellular and multicellular developmental variations in algal zygotes produce sporophytes.

Biology letters, 19(10):20230313.

The emergence of sporophytes, that is, diploid multicellular bodies in plants, facilitated plant diversification and the evolution of complexity. Although sporophytes may have evolved in an ancestral alga exhibiting a haplontic life cycle with a unicellular diploid and multicellular haploid (gametophyte) phase, the mechanism by which this novelty originated remains largely unknown. Ulotrichalean marine green algae (Ulvophyceae) are one of the few extant groups with haplontic-like life cycles. In this study, we show that zygotes of the ulotrichalean alga Monostroma angicava, which usually develop into unicellular cysts, exhibit a developmental variation producing multicellular reproductive sporophytes. Multicellular development likely occurred stochastically in individual zygotes, but its ratio responded plastically to growth conditions. Sporophytes showed identical morphological development to gametophytes, which should reflect the expression of the same genetic programme directing multicellular development. Considering that sporophytes were evolutionarily derived in Ulotrichales, this implies that sporophytes emerged by co-opting the gametophyte developmental programme to the diploid phase. This study suggests a possible mechanism of sporophyte formation in haplontic life cycles, contributing to the understanding of the evolutionary transition from unicellular to multicellular diploid body plans in green plants.

RevDate: 2023-10-22
CmpDate: 2023-10-22

Ma C, Li X, Xiao H, et al (2023)

Course-, dose-, and stage-dependent toxic effects of prenatal acetaminophen exposure on fetal long bone development.

Toxicology letters, 387:50-62.

Acetaminophen is a common analgesic and fever reduction medicine for pregnant women. Epidemiological studies suggest that prenatal acetaminophen exposure (PAcE) affects offspring health and development. However, the effects of PAcE on fetal long bone development and its potential mechanisms have not been elucidated. Based on clinical dosing characteristics, fetal mouse femurs were obtained for detection after oral gavage of acetaminophen at different doses (0, 100 or 400 mg/kg d), courses (single or multiple times) or stages (mid- or late pregnancy) during pregnancy in Kunming mice. The results showed that compared with the control group, PAcE reduced the length of total femur and the primary ossification center (POC), delayed the mineralization of POC and the ossification of epiphyseal region, and down-regulated the mRNA expression of osteogenic function markers (such as Runx2, Bsp, Ocn , Col1a1) in fetal femur, particularly in the high dose, multiple courses, and mid-pregnancy group. Meanwhile, the osteoclast and angiogenic function were also inhibited by PAcE at high dose, multiple courses, and mid-pregnancy, but the inhibition level was less than osteogenic function. Moreover, the alteration of canonical Wnt signalling pathway in PAcE fetal bone were consistent with its osteogenesis function changes. In conclusion, PAcE caused development toxicity and multi-cellular function inhibition in fetal long bone, particularly in the high dose, multiple treatments and mid-pregnancy group, and the alteration of canonical Wnt signalling pathway may be its potential mechanism.

RevDate: 2023-10-20

Mishina T, Chiu MC, Hashiguchi Y, et al (2023)

Massive horizontal gene transfer and the evolution of nematomorph-driven behavioral manipulation of mantids.

Current biology : CB pii:S0960-9822(23)01301-5 [Epub ahead of print].

To complete their life cycle, a wide range of parasites must manipulate the behavior of their hosts.[1] This manipulation is a well-known example of the "extended phenotype,[2]" where genes in one organism have phenotypic effects on another organism. Recent studies have explored the parasite genes responsible for such manipulation of host behavior, including the potential molecular mechanisms.[3][,][4] However, little is known about how parasites have acquired the genes involved in manipulating phylogenetically distinct hosts.[4] In a fascinating example of the extended phenotype, nematomorph parasites have evolved the ability to induce their terrestrial insect hosts to enter bodies of water, where the parasite then reproduces. Here, we comprehensively analyzed nematomorphs and their mantid hosts, focusing on the transcriptomic changes associated with host manipulations and sequence similarity between host and parasite genes to test molecular mimicry. The nematomorph's transcriptome changed during host manipulation, whereas no distinct changes were found in mantids. We then discovered numerous possible host-derived genes in nematomorphs, and these genes were frequently up-regulated during host manipulation. Our findings suggest a possible general role of horizontal gene transfer (HGT) in the molecular mechanisms of host manipulation, as well as in the genome evolution of manipulative parasites. The evidence of HGT between multicellular eukaryotes remains scarce but is increasing and, therefore, elucidating its mechanisms will advance our understanding of the enduring influence of HGT on the evolution of the web of life.

RevDate: 2023-10-14

Borodulina OR, Ustyantsev IG, DA Kramerov (2023)

SINEs as Potential Expression Cassettes: Impact of Deletions and Insertions on Polyadenylation and Lifetime of B2 and Ves SINE Transcripts Generated by RNA Polymerase III.

International journal of molecular sciences, 24(19): pii:ijms241914600.

Short Interspersed Elements (SINEs) are common in the genomes of most multicellular organisms. They are transcribed by RNA polymerase III from an internal promoter comprising boxes A and B. As transcripts of certain SINEs from mammalian genomes can be polyadenylated, such transcripts should contain the AATAAA sequence as well as those called β- and τ-signals. One of the goals of this work was to evaluate how autonomous and independent other SINE parts are β- and τ-signals. Extended regions outside of β- and τ-signals were deleted from SINEs B2 and Ves and the derived constructs were used to transfect HeLa cells in order to evaluate the relative levels of their transcripts as well as their polyadenylation efficiency. If the deleted regions affected boxes A and B, the 5'-flanking region of the U6 RNA gene with the external promoter was inserted upstream. Such substitution of the internal promoter in B2 completely restored its transcription. Almost all tested deletions/substitutions did not reduce the polyadenylation capacity of the transcripts, indicating a weak dependence of the function of β- and τ-signals on the neighboring sequences. A similar analysis of B2 and Ves constructs containing a 55-bp foreign sequence inserted between β- and τ-signals showed an equal polyadenylation efficiency of their transcripts compared to those of constructs without the insertion. The acquired poly(A)-tails significantly increased the lifetime and thus the cellular level of such transcripts. The data obtained highlight the potential of B2 and Ves SINEs as cassettes for the expression of relatively short sequences for various applications.

RevDate: 2023-10-12
CmpDate: 2023-10-12

Bourke AFG (2023)

Conflict and conflict resolution in the major transitions.

Proceedings. Biological sciences, 290(2008):20231420.

Conflict and conflict resolution have been argued to be fundamental to the major transitions in evolution. These were key events in life's history in which previously independently living individuals cooperatively formed a higher-level individual, such as a multicellular organism or eusocial colony. Conflict has its central role because, to proceed stably, the evolution of individuality in each major transition required within-individual conflict to be held in check. This review revisits the role of conflict and conflict resolution in the major transitions, addressing recent work arguing for a minor role. Inclusive fitness logic suggests that differences between the kin structures of clones and sexual families support the absence of conflict at the origin of multicellularity but, by contrast, suggest that key conflicts existed at the origin of eusociality. A principal example is conflict over replacing the founding queen (queen replacement). Following the origin of each transition, conflict remained important, because within-individual conflict potentially disrupts the attainment of maximal individuality (organismality) in the system. The conclusion is that conflict remains central to understanding the major transitions, essentially because conflict arises from differences in inclusive fitness optima while conflict resolution can help the system attain a high degree of coincidence of inclusive fitness interests.

RevDate: 2023-10-02

Igamberdiev AU, R Gordon (2023)

Macroevolution, differentiation trees, and the growth of coding systems.

Bio Systems pii:S0303-2647(23)00219-8 [Epub ahead of print].

An open process of evolution of multicellular organisms is based on the rearrangement and growth of the program of differentiation that underlies biological morphogenesis. The maintenance of the final (adult) stable non-equilibrium state (stasis) of a developmental system determines the direction of the evolutionary process. This state is achieved via the sequence of differentiation events representable as differentiation trees. A special type of morphogenetic code, acting as a metacode governing gene expression, may include electromechanical signals appearing as differentiation waves. The excessive energy due to the incorporation of mitochondria in eukaryotic cells resulted not only in more active metabolism but also in establishing the differentiation code for interconnecting cells and forming tissues, which fueled the evolutionary process. The "invention" of "continuing differentiation" distinguishes multicellular eukaryotes from multicellular prokaryotes. The Janus-faced control, involving both top-down control by differentiation waves and bottom-up control via the mechanical consequences of cell differentiations, underlies the process of morphogenesis and results in the achievement of functional stable final states. Duplications of branches of the differentiation tree may be the basis for continuing differentiation and macroevolution, analogous to gene duplication permitting divergence of genes. Metamorphoses, if they are proven to be fusions of disparate species, may be classified according to the topology of fusions of two differentiation trees. In the process of unfolding of morphogenetic structures, microevolution can be defined as changes of the differentiation tree that preserve topology of the tree, while macroevolution represents any change that alters the topology of the differentiation tree.

RevDate: 2023-09-28

Wegner L, Porth ML, K Ehlers (2023)

Multicellularity and the Need for Communication-A Systematic Overview on (Algal) Plasmodesmata and Other Types of Symplasmic Cell Connections.

Plants (Basel, Switzerland), 12(18): pii:plants12183342.

In the evolution of eukaryotes, the transition from unicellular to simple multicellular organisms has happened multiple times. For the development of complex multicellularity, characterized by sophisticated body plans and division of labor between specialized cells, symplasmic intercellular communication is supposed to be indispensable. We review the diversity of symplasmic connectivity among the eukaryotes and distinguish between distinct types of non-plasmodesmatal connections, plasmodesmata-like structures, and 'canonical' plasmodesmata on the basis of developmental, structural, and functional criteria. Focusing on the occurrence of plasmodesmata (-like) structures in extant taxa of fungi, brown algae (Phaeophyceae), green algae (Chlorophyta), and streptophyte algae, we present a detailed critical update on the available literature which is adapted to the present classification of these taxa and may serve as a tool for future work. From the data, we conclude that, actually, development of complex multicellularity correlates with symplasmic connectivity in many algal taxa, but there might be alternative routes. Furthermore, we deduce a four-step process towards the evolution of canonical plasmodesmata and demonstrate similarity of plasmodesmata in streptophyte algae and land plants with respect to the occurrence of an ER component. Finally, we discuss the urgent need for functional investigations and molecular work on cell connections in algal organisms.

RevDate: 2023-09-27
CmpDate: 2023-09-27

Aanen DK, van 't Padje A, B Auxier (2023)

Longevity of Fungal Mycelia and Nuclear Quality Checks: a New Hypothesis for the Role of Clamp Connections in Dikaryons.

Microbiology and molecular biology reviews : MMBR, 87(3):e0002221.

This paper addresses the stability of mycelial growth in fungi and differences between ascomycetes and basidiomycetes. Starting with general evolutionary theories of multicellularity and the role of sex, we then discuss individuality in fungi. Recent research has demonstrated the deleterious consequences of nucleus-level selection in fungal mycelia, favoring cheaters with a nucleus-level benefit during spore formation but a negative effect on mycelium-level fitness. Cheaters appear to generally be loss-of-fusion (LOF) mutants, with a higher propensity to form aerial hyphae developing into asexual spores. Since LOF mutants rely on heterokaryosis with wild-type nuclei, we argue that regular single-spore bottlenecks can efficiently select against such cheater mutants. We then zoom in on ecological differences between ascomycetes being typically fast-growing but short-lived with frequent asexual-spore bottlenecks and basidiomycetes being generally slow-growing but long-lived and usually without asexual-spore bottlenecks. We argue that these life history differences have coevolved with stricter nuclear quality checks in basidiomycetes. Specifically, we propose a new function for clamp connections, structures formed during the sexual stage in ascomycetes and basidiomycetes but during somatic growth only in basidiomycete dikaryons. During dikaryon cell division, the two haploid nuclei temporarily enter a monokaryotic phase, by alternatingly entering a retrograde-growing clamp cell, which subsequently fuses with the subapical cell to recover the dikaryotic cell. We hypothesize that clamp connections act as screening devices for nuclear quality, with both nuclei continuously testing each other for fusion ability, a test that LOF mutants will fail. By linking differences in longevity of the mycelial phase to ecology and stringency of nuclear quality checks, we propose that mycelia have a constant and low lifetime cheating risk, irrespective of their size and longevity.

RevDate: 2023-09-21
CmpDate: 2023-09-21

Kalambokidis M, M Travisano (2023)

Multispecies interactions shape the transition to multicellularity.

Proceedings. Biological sciences, 290(2007):20231055.

The origin of multicellularity transformed the adaptive landscape on Earth, opening diverse avenues for further innovation. The transition to multicellular life is understood as the evolution of cooperative groups which form a new level of individuality. Despite the potential for community-level interactions, most studies have not addressed the competitive context of this transition, such as competition between species. Here, we explore how interspecific competition shapes the emergence of multicellularity in an experimental system with two yeast species, Saccharomyces cerevisiae and Kluyveromyces lactis, where multicellularity evolves in response to selection for faster settling ability. We find that the multispecies context slows the rate of the transition to multicellularity, and the transition to multicellularity significantly impacts community composition. Multicellular K. lactis emerges first and sweeps through populations in monocultures faster than in cocultures with S. cerevisiae. Following the transition, the between-species competitive dynamics shift, likely in part to intraspecific cooperation in K. lactis. Hence, we document an eco-evolutionary feedback across the transition to multicellularity, underscoring how ecological context is critical for understanding the causes and consequences of innovation. By including two species, we demonstrate that cooperation and competition across several biological scales shapes the origin and persistence of multicellularity.

RevDate: 2023-09-21
CmpDate: 2023-09-21

Takeuchi K, Senda M, Ikeda Y, et al (2023)

Functional molecular evolution of a GTP sensing kinase: PI5P4Kβ.

The FEBS journal, 290(18):4419-4428.

Over 4 billion years of evolution, multiple mutations, including nucleotide substitutions, gene and genome duplications and recombination, have established de novo genes that translate into proteins with novel properties essential for high-order cellular functions. However, molecular processes through which a protein evolutionarily acquires a novel function are mostly speculative. Recently, we have provided evidence for a potential evolutionary mechanism underlying how, in mammalian cells, phosphatidylinositol 5-phosphate 4-kinase β (PI5P4Kβ) evolved into a GTP sensor from ATP-utilizing kinase. Mechanistically, PI5P4Kβ has acquired the guanine efficient association (GEA) motif by mutating its nucleotide base recognition sequence, enabling the evolutionary transition from an ATP-dependent kinase to a distinct GTP/ATP dual kinase with its KM for GTP falling into physiological GTP concentrations-the genesis of GTP sensing activity. Importantly, the GTP sensing activity of PI5P4Kβ is critical for the manifestation of cellular metabolism and tumourigenic activity in the multicellular organism. The combination of structural, biochemical and biophysical analyses used in our study provides a novel framework for analysing how a protein can evolutionarily acquire a novel activity, which potentially introduces a critical function to the cell.

RevDate: 2023-09-20

Craig JM, Kumar S, SB Hedges (2023)

The origin of eukaryotes and rise in complexity were synchronous with the rise in oxygen.

Frontiers in bioinformatics, 3:1233281.

The origin of eukaryotes was among the most important events in the history of life, spawning a new evolutionary lineage that led to all complex multicellular organisms. However, the timing of this event, crucial for understanding its environmental context, has been difficult to establish. The fossil and biomarker records are sparse and molecular clocks have thus far not reached a consensus, with dates spanning 2.1-0.91 billion years ago (Ga) for critical nodes. Notably, molecular time estimates for the last common ancestor of eukaryotes are typically hundreds of millions of years younger than the Great Oxidation Event (GOE, 2.43-2.22 Ga), leading researchers to question the presumptive link between eukaryotes and oxygen. We obtained a new time estimate for the origin of eukaryotes using genetic data of both archaeal and bacterial origin, the latter rarely used in past studies. We also avoided potential calibration biases that may have affected earlier studies. We obtained a conservative interval of 2.2-1.5 Ga, with an even narrower core interval of 2.0-1.8 Ga, for the origin of eukaryotes, a period closely aligned with the rise in oxygen. We further reconstructed the history of biological complexity across the tree of life using three universal measures: cell types, genes, and genome size. We found that the rise in complexity was temporally consistent with and followed a pattern similar to the rise in oxygen. This suggests a causal relationship stemming from the increased energy needs of complex life fulfilled by oxygen.

RevDate: 2023-09-18
CmpDate: 2023-09-18

Huang L, Tu Z, Wei L, et al (2023)

Generating Functional Multicellular Organoids from Human Placenta Villi.

Advanced science (Weinheim, Baden-Wurttemberg, Germany), 10(26):e2301565.

The interaction between trophoblasts, stroma cells, and immune cells at the maternal-fetal interface constitutes the functional units of the placenta, which is crucial for successful pregnancy outcomes. However, the investigation of this intricate interplay is restricted due to the absence of efficient experimental models. To address this challenge, a robust, reliable methodology for generating placenta villi organoids (PVOs) from early, late, or diseased pregnancies using air-liquid surface culture is developed. PVOs contain cytotrophoblasts that can self-renew and differentiate directly, along with stromal elements that retain native immune cells. Analysis of scRNA sequencing and WES data reveals that PVOs faithfully recapitulate the cellular components and genetic alterations of the corresponding source tissue. Additionally, PVOs derived from patients with preeclampsia exhibit specific pathological features such as inflammation, antiangiogenic imbalance, and decreased syncytin expression. The PVO-based propagation of primary placenta villi should enable a deeper investigation of placenta development and exploration of the underlying pathogenesis and therapeutics of placenta-originated diseases.

RevDate: 2023-09-18
CmpDate: 2023-09-18

Ruiz-Trillo I, Kin K, E Casacuberta (2023)

The Origin of Metazoan Multicellularity: A Potential Microbial Black Swan Event.

Annual review of microbiology, 77:499-516.

The emergence of animals from their unicellular ancestors is a major evolutionary event. Thanks to the study of diverse close unicellular relatives of animals, we now have a better grasp of what the unicellular ancestor of animals was like. However, it is unclear how that unicellular ancestor of animals became the first animals. To explain this transition, two popular theories, the choanoblastaea and the synzoospore, have been proposed. We will revise and expose the flaws in these two theories while showing that, due to the limits of our current knowledge, the origin of animals is a biological black swan event. As such, the origin of animals defies retrospective explanations. Therefore, we should be extra careful not to fall for confirmation biases based on few data and, instead, embrace this uncertainty and be open to alternative scenarios. With the aim to broaden the potential explanations on how animals emerged, we here propose two novel and alternative scenarios. In any case, to find the answer to how animals evolved, additional data will be required, as will the hunt for microscopic creatures that are closely related to animals but have not yet been sampled and studied.

RevDate: 2023-09-15
CmpDate: 2023-09-15

Shalev O, Ye X, C Ratzke (2023)

Replaying the evolution of multicellularity.

Trends in ecology & evolution, 38(10):910-912.

The first organisms on Earth were presumably unicellular. At one point, evolution shaped these individual cells into multicellular organisms, which was a significant transition in the history of life on Earth. To investigate how this change happened, Bozdag et al. re-ran evolution in the lab and observed how single-celled yeast forms large multicellular aggregates.

RevDate: 2023-09-14
CmpDate: 2023-09-14

Azimzadeh J, B Durand (2023)

Evolution: The ancient history of cilia assembly regulation.

Current biology : CB, 33(17):R898-R900.

A new study identifies a conserved regulatory mechanism for cilia assembly in the closest unicellular relatives of animals, suggesting that this mechanism was already present in a common unicellular ancestor and was repurposed during the transition to multicellularity.

RevDate: 2023-09-08
CmpDate: 2023-09-08

Palmiero M, Cantarosso I, di Blasio L, et al (2023)

Collective directional migration drives the formation of heteroclonal cancer cell clusters.

Molecular oncology, 17(9):1699-1725.

Metastasisation occurs through the acquisition of invasive and survival capabilities that allow tumour cells to colonise distant sites. While the role of multicellular aggregates in cancer dissemination is acknowledged, the mechanisms that drive the formation of multiclonal cell aggregates are not fully elucidated. Here, we show that cancer cells of different tissue of origins can perform collective directional migration and can actively form heteroclonal aggregates in 3D, through a proliferation-independent mechanism. Coalescence of distant cell clusters is mediated by subcellular actin-rich protrusions and multicellular outgrowths that extend towards neighbouring aggregates. Coherently, perturbation of cytoskeletal dynamics impairs collective migration while myosin II activation is necessary for multicellular movements. We put forward the hypothesis that cluster attraction is mediated by secreted soluble factors. Such a hypothesis is consistent with the abrogation of aggregation by inhibition of PI3K/AKT/mTOR and MEK/ERK, the chemoattracting activity of conditioned culture media and with a wide screening of secreted proteins. Our results present a novel collective migration model and shed light on the mechanisms of formation of heteroclonal aggregates in cancer.

RevDate: 2023-09-06
CmpDate: 2023-09-06

Garte S (2023)

Targeted Hypermutation as a Survival Strategy: A Theoretical Approach.

Acta biotheoretica, 71(4):20.

Targeted hypermutation has proven to be a useful survival strategy for bacteria under severe stress and is also used by multicellular organisms in specific instances such as the mammalian immune system. This might appear surprising, given the generally observed deleterious effects of poor replication fidelity/high mutation rate. A previous theoretical model designed to explore the role of replication fidelity in the origin of life was applied to a simulated hypermutation scenario. The results confirmed that the same model is useful for analyzing hypermutation and can predict the effects of the same parameters (survival probability, replication fidelity, mutation effect, and others) on the survival of cellular populations undergoing hypermutation as a result of severe stress.

RevDate: 2023-09-06
CmpDate: 2023-09-06

Corallo D, Dalla Vecchia M, Lazic D, et al (2023)

The molecular basis of tumor metastasis and current approaches to decode targeted migration-promoting events in pediatric neuroblastoma.

Biochemical pharmacology, 215:115696.

Cell motility is a crucial biological process that plays a critical role in the development of multicellular organisms and is essential for tissue formation and regeneration. However, uncontrolled cell motility can lead to the development of various diseases, including neoplasms. In this review, we discuss recent advances in the discovery of regulatory mechanisms underlying the metastatic spread of neuroblastoma, a solid pediatric tumor that originates in the embryonic migratory cells of the neural crest. The highly motile phenotype of metastatic neuroblastoma cells requires targeting of intracellular and extracellular processes, that, if affected, would be helpful for the treatment of high-risk patients with neuroblastoma, for whom current therapies remain inadequate. Development of new potentially migration-inhibiting compounds and standardized preclinical approaches for the selection of anti-metastatic drugs in neuroblastoma will also be discussed.

RevDate: 2023-09-06
CmpDate: 2023-09-06

Kato D, Aoyama Y, Nishida K, et al (2023)

Regulation of lipid synthesis in myelin modulates neural activity and is required for motor learning.

Glia, 71(11):2591-2608.

Brain function relies on both rapid electrical communication in neural circuitry and appropriate patterns or synchrony of neural activity. Rapid communication between neurons is facilitated by wrapping nerve axons with insulation by a myelin sheath composed largely of different lipids. Recent evidence has indicated that the extent of myelination of nerve axons can adapt based on neural activity levels and this adaptive myelination is associated with improved learning of motor tasks, suggesting such plasticity may enhance effective learning. In this study, we examined whether another aspect of myelin plasticity-changes in myelin lipid synthesis and composition-may also be associated with motor learning. We combined a motor learning task in mice with in vivo two-photon imaging of neural activity in the primary motor cortex (M1) to distinguish early and late stages of learning and then probed levels of some key myelin lipids using mass spectrometry analysis. Sphingomyelin levels were elevated in the early stage of motor learning while galactosylceramide levels were elevated in the middle and late stages of motor learning, and these changes were correlated across individual mice with both learning performance and neural activity changes. Targeted inhibition of oligodendrocyte-specific galactosyltransferase expression, the enzyme that synthesizes myelin galactosylceramide, impaired motor learning. Our results suggest regulation of myelin lipid composition could be a novel facet of myelin adaptations associated with learning.

RevDate: 2023-08-31

Borg M, Krueger-Hadfield SA, Destombe C, et al (2023)

Red macroalgae in the genomic era.

The New phytologist [Epub ahead of print].

Rhodophyta (or red algae) are a diverse and species-rich group that forms one of three major lineages in the Archaeplastida, a eukaryotic supergroup whose plastids arose from a single primary endosymbiosis. Red algae are united by several features, such as relatively small intron-poor genomes and a lack of cytoskeletal structures associated with motility like flagella and centrioles, as well as a highly efficient photosynthetic capacity. Multicellular red algae (or macroalgae) are one of the earliest diverging eukaryotic lineages to have evolved complex multicellularity, yet despite their ecological, evolutionary, and commercial importance, they have remained a largely understudied group of organisms. Considering the increasing availability of red algal genome sequences, we present a broad overview of fundamental aspects of red macroalgal biology and posit on how this is expected to accelerate research in many domains of red algal biology in the coming years.

RevDate: 2023-08-30

Hall G, Kelly S, Schaap P, et al (2022)

Phylogeny-wide analysis of G-protein coupled receptors in social amoebas and implications for the evolution of multicellularity.

Open research Europe, 2:134.

G-protein coupled receptors (GPCRs) are seven-transmembrane proteins and constitute the largest group of receptors within eukaryotes. The presence of a large set of GPCRs in the unicellular Amoebozoa was surprising and is indicative of the largely undiscovered environmental sensing capabilities in this group. Evolutionary transitions from unicellular to multicellular lifestyles, like we see in social amoebas, have occurred several times independently in the Amoebozoa, and GPCRs may have been co-opted for new functions in cell-cell communication. Methods We have analysed a set of GPCRs from fully sequenced Amoebozoan genomes by Bayesian inference, compared their phylogenetic distribution and domain composition, and analysed their temporal and spatial expression patterns in five species of dictyostelids. Results We found evidence that most GPCRs are conserved deeply in the Amoebozoa and are probably performing roles in general cell functions and complex environmental sensing. All families of GPCRs (apart from the family 4 fungal pheromone receptors) are present in dictyostelids with family 5 being the largest and family 2 the one with the fewest members. For the first time, we identify the presence of family 1 rhodopsin-like GPCRs in dictyostelids. Some GPCRs have been amplified in the dictyostelids and in specific lineages thereof and through changes in expression patterns may have been repurposed for signalling in multicellular development. Discussion Our phylogenetic analysis suggests that GPCR families 1, 2 and 6 already diverged early in the Amoebozoa, whereas families 3 and 5 expanded later within the dictyostelids. The family 6 cAMP receptors that have experimentally supported roles in multicellular development in dictyostelids (carA-carD; tasA/B) originated at the root of all dictyostelids and only have weakly associated homologs in Physarum polycephalum. Our analysis identified candidate GPCRs which have evolved in the dictyostelids and could have been co-opted for multicellular development.

RevDate: 2023-08-28
CmpDate: 2023-08-28

Cervantes S, Kesälahti R, Kumpula TA, et al (2023)

Strong Purifying Selection in Haploid Tissue-Specific Genes of Scots Pine Supports the Masking Theory.

Molecular biology and evolution, 40(8):.

The masking theory states that genes expressed in a haploid stage will be under more efficient selection. In contrast, selection will be less efficient in genes expressed in a diploid stage, where the fitness effects of recessive deleterious or beneficial mutations can be hidden from selection in heterozygous form. This difference can influence several evolutionary processes such as the maintenance of genetic variation, adaptation rate, and genetic load. Masking theory expectations have been confirmed in single-cell haploid and diploid organisms. However, in multicellular organisms, such as plants, the effects of haploid selection are not clear-cut. In plants, the great majority of studies indicating haploid selection have been carried out using male haploid tissues in angiosperms. Hence, evidence in these systems is confounded with the effects of sexual selection and intraspecific competition. Evidence from other plant groups is scarce, and results show no support for the masking theory. Here, we have used a gymnosperm Scots pine megagametophyte, a maternally derived seed haploid tissue, and four diploid tissues to test the strength of purifying selection on a set of genes with tissue-specific expression. By using targeted resequencing data of those genes, we obtained estimates of genetic diversity, the site frequency spectrum of 0-fold and 4-fold sites, and inferred the distribution of fitness effects of new mutations in haploid and diploid tissue-specific genes. Our results show that purifying selection is stronger for tissue-specific genes expressed in the haploid megagametophyte tissue and that this signal of strong selection is not an artifact driven by high expression levels.

RevDate: 2023-08-18
CmpDate: 2023-06-21

Sarkar MMH, Rahman MS, Islam MR, et al (2023)

Comparative phylogenetic analysis and transcriptomic profiling of Dengue (DENV-3 genotype I) outbreak in 2021 in Bangladesh.

Virology journal, 20(1):127.

BACKGROUND: The next-generation sequencing (NGS) technology facilitates in-depth study of host-pathogen metatranscriptome. We, therefore, implicated phylodynamic and transcriptomic approaches through NGS technology to know/understand the dengue virus (DENV) origin and host response with dengue fever.

METHODS: In this study, blood serum RNA was extracted from 21 dengue patients and 3 healthy individuals. Total transcriptomic data were analyzed for phylogenetic, phylodynamic, differential express gene (DEG), and gene ontology (GO) using respective bioinformatics tools.

RESULTS: The viral genome sequence revealed dengue viral genome size ranges 10647 to 10707 nucleotide. Phylogenetic and phylodynamic analysis showed that the 2021 epidemic isolates were DENV-3 genotype-I and maintained as a new clade in compared to 2019 epidemic. Transcriptome analysis showed a total of 2686 genes were DEG in dengue patients compared to control with a q-value < 0.05. DESeq2 plot counts function of the top 24 genes with the smallest q-values of differential gene expression of RNA-seq data showed that 11 genes were upregulated, whereas 13 genes were downregulated. GO analysis showed a significant upregulation (p = < 0.001) in a process of multicellular organismal, nervous system, sensory perception of chemical stimulus, and G protein-coupled receptor signaling pathways in the dengue patients. However, there were a significant downregulation (p = < 0.001) of intracellular component, cellular anatomical entity, and protein-containing complex in dengue patients. Most importantly, there was a significant increase of a class of immunoregulatory proteins in dengue patients in compared to the controls, with increased GO of immune system process. In addition, upregulation of toll receptor (TLR) signaling pathways were found in dengue patients. These TLR pathways were particularly involved for the activation of innate system coupled with adaptive immune system that probably involved the rapid elimination of dengue virus infected cells. These differentially expressed genes could be further investigated for target based prophylactic interventions for dengue.

CONCLUSION: This is a first report describing DENV complete genomic features and differentially expressed genes in patients in Bangladesh. These genes may have diagnostic and therapeutic values for dengue infection. Continual genomic surveillance is required to further investigate the shift in dominant genotypes in relation to viral pathogenesis.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12985-023-02030-1.

RevDate: 2023-08-11
CmpDate: 2023-08-10

Ma X, Shi X, Wang Q, et al (2023)

A Reinvestigation of Multiple Independent Evolution and Triassic-Jurassic Origins of Multicellular Volvocine Algae.

Genome biology and evolution, 15(8):.

The evolution of multicellular organisms is considered to be a major evolutionary transition, profoundly affecting the ecology and evolution of nearly all life on earth. The volvocine algae, a unique clade of chlorophytes with diverse cell morphology, provide an appealing model for investigating the evolution of multicellularity and development. However, the phylogenetic relationship and timescale of the volvocine algae are not fully resolved. Here, we use extensive taxon and gene sampling to reconstruct the phylogeny of the volvocine algae. Our results support that the colonial volvocine algae are not monophyletic group and multicellularity independently evolve at least twice in the volvocine algae, once in Tetrabaenaceae and another in the Goniaceae + Volvocaceae. The simulation analyses suggest that incomplete lineage sorting is a major factor for the tree topology discrepancy, which imply that the multispecies coalescent model better fits the data used in this study. The coalescent-based species tree supports that the Goniaceae is monophyletic and Crucicarteria is the earliest diverging lineage, followed by Hafniomonas and Radicarteria within the Volvocales. By considering the multiple uncertainties in divergence time estimation, the dating analyses indicate that the volvocine algae occurred during the Cryogenian to Ediacaran (696.6-551.1 Ma) and multicellularity in the volvocine algae originated from the Triassic to Jurassic. Our phylogeny and timeline provide an evolutionary framework for studying the evolution of key traits and the origin of multicellularity in the volvocine algae.

RevDate: 2023-08-09
CmpDate: 2023-08-09

Merényi Z, Krizsán K, Sahu N, et al (2023)

Genomes of fungi and relatives reveal delayed loss of ancestral gene families and evolution of key fungal traits.

Nature ecology & evolution, 7(8):1221-1231.

Fungi are ecologically important heterotrophs that have radiated into most niches on Earth and fulfil key ecological services. Despite intense interest in their origins, major genomic trends of their evolutionary route from a unicellular opisthokont ancestor to derived multicellular fungi remain poorly known. Here we provide a highly resolved genome-wide catalogue of gene family changes across fungal evolution inferred from the genomes of 123 fungi and relatives. We show that a dominant trend in early fungal evolution has been the gradual shedding of protist genes and the punctuated emergence of innovation by two main gene duplication events. We find that the gene content of non-Dikarya fungi resembles that of unicellular opisthokonts in many respects, owing to the conservation of protist genes in their genomes. The most rapidly duplicating gene groups included extracellular proteins and transcription factors, as well as ones linked to the coordination of nutrient uptake with growth, highlighting the transition to a sessile osmotrophic feeding strategy and subsequent lifestyle evolution as important elements of early fungal history. These results suggest that the genomes of pre-fungal ancestors evolved into the typical filamentous fungal genome by a combination of gradual gene loss, turnover and several large duplication events rather than by abrupt changes. Consequently, the taxonomically defined Fungi represents a genomically non-uniform assemblage of species.

RevDate: 2023-08-07
CmpDate: 2023-08-07

Sartor F, Xu X, Popp T, et al (2023)

The circadian clock of the bacterium B. subtilis evokes properties of complex, multicellular circadian systems.

Science advances, 9(31):eadh1308.

Circadian clocks are pervasive throughout nature, yet only recently has this adaptive regulatory program been described in nonphotosynthetic bacteria. Here, we describe an inherent complexity in the Bacillus subtilis circadian clock. We find that B. subtilis entrains to blue and red light and that circadian entrainment is separable from masking through fluence titration and frequency demultiplication protocols. We identify circadian rhythmicity in constant light, consistent with the Aschoff's rule, and entrainment aftereffects, both of which are properties described for eukaryotic circadian clocks. We report that circadian rhythms occur in wild isolates of this prokaryote, thus establishing them as a general property of this species, and that its circadian system responds to the environment in a complex fashion that is consistent with multicellular eukaryotic circadian systems.

RevDate: 2023-08-01
CmpDate: 2023-07-31

Erenpreisa J, Vainshelbaum NM, Lazovska M, et al (2023)

The Price of Human Evolution: Cancer-Testis Antigens, the Decline in Male Fertility and the Increase in Cancer.

International journal of molecular sciences, 24(14):.

The increasing frequency of general and particularly male cancer coupled with the reduction in male fertility seen worldwide motivated us to seek a potential evolutionary link between these two phenomena, concerning the reproductive transcriptional modules observed in cancer and the expression of cancer-testis antigens (CTA). The phylostratigraphy analysis of the human genome allowed us to link the early evolutionary origin of cancer via the reproductive life cycles of the unicellulars and early multicellulars, potentially driving soma-germ transition, female meiosis, and the parthenogenesis of polyploid giant cancer cells (PGCCs), with the expansion of the CTA multi-families, very late during their evolution. CTA adaptation was aided by retrovirus domestication in the unstable genomes of mammals, for protecting male fertility in stress conditions, particularly that of humans, as compensation for the energy consumption of a large complex brain which also exploited retrotransposition. We found that the early and late evolutionary branches of human cancer are united by the immunity-proto-placental network, which evolved in the Cambrian and shares stress regulators with the finely-tuned sex determination system. We further propose that social stress and endocrine disruption caused by environmental pollution with organic materials, which alter sex determination in male foetuses and further spermatogenesis in adults, bias the development of PGCC-parthenogenetic cancer by default.

RevDate: 2023-08-07
CmpDate: 2023-07-28

Fichman Y, Rowland L, Oliver MJ, et al (2023)

ROS are evolutionary conserved cell-to-cell stress signals.

Proceedings of the National Academy of Sciences of the United States of America, 120(31):e2305496120.

Cell-to-cell communication is fundamental to multicellular organisms and unicellular organisms living in a microbiome. It is thought to have evolved as a stress- or quorum-sensing mechanism in unicellular organisms. A unique cell-to-cell communication mechanism that uses reactive oxygen species (ROS) as a signal (termed the "ROS wave") was identified in flowering plants. This process is essential for systemic signaling and plant acclimation to stress and can spread from a small group of cells to the entire plant within minutes. Whether a similar signaling process is found in other organisms is however unknown. Here, we report that the ROS wave can be found in unicellular algae, amoeba, ferns, mosses, mammalian cells, and isolated hearts. We further show that this process can be triggered in unicellular and multicellular organisms by a local stress or H2O2 treatment and blocked by the application of catalase or NADPH oxidase inhibitors and that in unicellular algae it communicates important stress-response signals between cells. Taken together, our findings suggest that an active process of cell-to-cell ROS signaling, like the ROS wave, evolved before unicellular and multicellular organisms diverged. This mechanism could have communicated an environmental stress signal between cells and coordinated the acclimation response of many different cells living in a community. The finding of a signaling process, like the ROS wave, in mammalian cells further contributes to our understanding of different diseases and could impact the development of drugs that target for example cancer or heart disease.

RevDate: 2023-07-26
CmpDate: 2023-07-21

Vroomans RMA, ES Colizzi (2023)

Evolution of selfish multicellularity: collective organisation of individual spatio-temporal regulatory strategies.

BMC ecology and evolution, 23(1):35.

BACKGROUND: The unicellular ancestors of modern-day multicellular organisms were remarkably complex. They had an extensive set of regulatory and signalling genes, an intricate life cycle and could change their behaviour in response to environmental changes. At the transition to multicellularity, some of these behaviours were co-opted to organise the development of the nascent multicellular organism. Here, we focus on the transition to multicellularity before the evolution of stable cell differentiation, to reveal how the emergence of clusters affects the evolution of cell behaviour.

RESULTS: We construct a computational model of a population of cells that can evolve the regulation of their behavioural state - either division or migration - and study both a unicellular and a multicellular context. Cells compete for reproduction and for resources to survive in a seasonally changing environment. We find that the evolution of multicellularity strongly determines the co-evolution of cell behaviour, by altering the competition dynamics between cells. When adhesion cannot evolve, cells compete for survival by rapidly migrating towards resources before dividing. When adhesion evolves, emergent collective migration alleviates the pressure on individual cells to reach resources. This allows individual cells to maximise their own replication. Migrating adhesive clusters display striking patterns of spatio-temporal cell state changes that visually resemble animal development.

CONCLUSIONS: Our model demonstrates how emergent selection pressures at the onset of multicellularity can drive the evolution of cellular behaviour to give rise to developmental patterns.

RevDate: 2023-07-18
CmpDate: 2023-07-17

Endres K, K Friedland (2023)

Talk to Me-Interplay between Mitochondria and Microbiota in Aging.

International journal of molecular sciences, 24(13):.

The existence of mitochondria in eukaryotic host cells as a remnant of former microbial organisms has been widely accepted, as has their fundamental role in several diseases and physiological aging. In recent years, it has become clear that the health, aging, and life span of multicellular hosts are also highly dependent on the still-residing microbiota, e.g., those within the intestinal system. Due to the common evolutionary origin of mitochondria and these microbial commensals, it is intriguing to investigate if there might be a crosstalk based on preserved common properties. In the light of rising knowledge on the gut-brain axis, such crosstalk might severely affect brain homeostasis in aging, as neuronal tissue has a high energy demand and low tolerance for according functional decline. In this review, we summarize what is known about the impact of both mitochondria and the microbiome on the host's aging process and what is known about the aging of both entities. For a long time, bacteria were assumed to be immortal; however, recent evidence indicates their aging and similar observations have been made for mitochondria. Finally, we present pathways by which mitochondria are affected by microbiota and give information about therapeutic anti-aging approaches that are based on current knowledge.

RevDate: 2023-07-18
CmpDate: 2023-07-14

Geng S, Hamaji T, Ferris PJ, et al (2023)

A conserved RWP-RK transcription factor VSR1 controls gametic differentiation in volvocine algae.

Proceedings of the National Academy of Sciences of the United States of America, 120(29):e2305099120.

Volvocine green algae are a model for understanding the evolution of mating types and sexes. They are facultatively sexual, with gametic differentiation occurring in response to nitrogen starvation (-N) in most genera and to sex inducer hormone in Volvox. The conserved RWP-RK family transcription factor (TF) MID is encoded by the minus mating-type locus or male sex-determining region of heterothallic volvocine species and dominantly determines minus or male gametic differentiation. However, the factor(s) responsible for establishing the default plus or female differentiation programs have remained elusive. We performed a phylo-transcriptomic screen for autosomal RWP-RK TFs induced during gametogenesis in unicellular isogamous Chlamydomonas reinhardtii (Chlamydomonas) and in multicellular oogamous Volvox carteri (Volvox) and identified a single conserved ortho-group we named Volvocine Sex Regulator 1 (VSR1). Chlamydomonas vsr1 mutants of either mating type failed to mate and could not induce expression of key mating-type-specific genes. Similarly, Volvox vsr1 mutants in either sex could initiate sexual embryogenesis, but the presumptive eggs or androgonidia (sperm packet precursors) were infertile and unable to express key sex-specific genes. Yeast two-hybrid assays identified a conserved domain in VSR1 capable of self-interaction or interaction with the conserved N terminal domain of MID. In vivo coimmunoprecipitation experiments demonstrated association of VSR1 and MID in both Chlamydomonas and Volvox. These data support a new model for volvocine sexual differentiation where VSR1 homodimers activate expression of plus/female gamete-specific-genes, but when MID is present, MID-VSR1 heterodimers are preferentially formed and activate minus/male gamete-specific-genes.

RevDate: 2023-07-13

Mondal A, MS Bansal (2023)

Generalizing the Domain-Gene-Species Reconciliation Framework to Microbial Genes and Domains.

IEEE/ACM transactions on computational biology and bioinformatics, PP: [Epub ahead of print].

Protein domains play an important role in the function and evolution of many gene families. Previous studies have shown that domains are frequently lost or gained during gene family evolution. Yet, most computational approaches for studying gene family evolution do not account for domain-level evolution within genes. To address this limitation, a new three-level reconciliation framework, called the Domain-Gene-Species (DGS) reconciliation model, has been recently developed to simultaneously model the evolution of a domain family inside one or more gene families and the evolution of those gene families inside a species tree. However, the existing model applies only to multi-cellular eukaryotes where horizontal gene transfer is negligible. In this work, we generalize the existing DGS reconciliation model by allowing for the spread of genes and domains across species boundaries through horizontal transfer. We show that the problem of computing optimal generalized DGS reconciliations, though NP-hard, is approximable to within a constant factor, where the specific approximation ratio depends on the "event costs" used. We provide two different approximation algorithms for the problem and demonstrate the impact of the generalized framework using both simulated and real biological data. Our results show that our new algorithms result in highly accurate reconstructions of domain family evolution for microbes.

RevDate: 2023-07-18
CmpDate: 2023-07-06

Stevenson ZC, Moerdyk-Schauwecker MJ, Banse SA, et al (2023)

High-throughput library transgenesis in Caenorhabditis elegans via Transgenic Arrays Resulting in Diversity of Integrated Sequences (TARDIS).

eLife, 12:.

High-throughput transgenesis using synthetic DNA libraries is a powerful method for systematically exploring genetic function. Diverse synthesized libraries have been used for protein engineering, identification of protein-protein interactions, characterization of promoter libraries, developmental and evolutionary lineage tracking, and various other exploratory assays. However, the need for library transgenesis has effectively restricted these approaches to single-cell models. Here, we present Transgenic Arrays Resulting in Diversity of Integrated Sequences (TARDIS), a simple yet powerful approach to large-scale transgenesis that overcomes typical limitations encountered in multicellular systems. TARDIS splits the transgenesis process into a two-step process: creation of individuals carrying experimentally introduced sequence libraries, followed by inducible extraction and integration of individual sequences/library components from the larger library cassette into engineered genomic sites. Thus, transformation of a single individual, followed by lineage expansion and functional transgenesis, gives rise to thousands of genetically unique transgenic individuals. We demonstrate the power of this system using engineered, split selectable TARDIS sites in Caenorhabditis elegans to generate (1) a large set of individually barcoded lineages and (2) transcriptional reporter lines from predefined promoter libraries. We find that this approach increases transformation yields up to approximately 1000-fold over current single-step methods. While we demonstrate the utility of TARDIS using C. elegans, in principle the process is adaptable to any system where experimentally generated genomic loci landing pads and diverse, heritable DNA elements can be generated.

RevDate: 2023-07-03
CmpDate: 2023-07-03

Kapsetaki SE, Fortunato A, Compton Z, et al (2023)

Is chimerism associated with cancer across the tree of life?.

PloS one, 18(6):e0287901.

Chimerism is a widespread phenomenon across the tree of life. It is defined as a multicellular organism composed of cells from other genetically distinct entities. This ability to 'tolerate' non-self cells may be linked to susceptibility to diseases like cancer. Here we test whether chimerism is associated with cancers across obligately multicellular organisms in the tree of life. We classified 12 obligately multicellular taxa from lowest to highest chimerism levels based on the existing literature on the presence of chimerism in these species. We then tested for associations of chimerism with tumour invasiveness, neoplasia (benign or malignant) prevalence and malignancy prevalence in 11 terrestrial mammalian species. We found that taxa with higher levels of chimerism have higher tumour invasiveness, though there was no association between malignancy or neoplasia and chimerism among mammals. This suggests that there may be an important biological relationship between chimerism and susceptibility to tissue invasion by cancerous cells. Studying chimerism might help us identify mechanisms underlying invasive cancers and also could provide insights into the detection and management of emerging transmissible cancers.

RevDate: 2023-07-13
CmpDate: 2023-07-03

Römling U, Cao LY, FW Bai (2023)

Evolution of cyclic di-GMP signalling on a short and long term time scale.

Microbiology (Reading, England), 169(6):.

Diversifying radiation of domain families within specific lineages of life indicates the importance of their functionality for the organisms. The foundation for the diversifying radiation of the cyclic di-GMP signalling network that occurred within the bacterial kingdom is most likely based in the outmost adaptability, flexibility and plasticity of the system. Integrative sensing of multiple diverse extra- and intracellular signals is made possible by the N-terminal sensory domains of the modular cyclic di-GMP turnover proteins, mutations in the protein scaffolds and subsequent signal reception by diverse receptors, which eventually rewires opposite host-associated as well as environmental life styles including parallel regulated target outputs. Natural, laboratory and microcosm derived microbial variants often with an altered multicellular biofilm behaviour as reading output demonstrated single amino acid substitutions to substantially alter catalytic activity including substrate specificity. Truncations and domain swapping of cyclic di-GMP signalling genes and horizontal gene transfer suggest rewiring of the network. Presence of cyclic di-GMP signalling genes on horizontally transferable elements in particular observed in extreme acidophilic bacteria indicates that cyclic di-GMP signalling and biofilm components are under selective pressure in these types of environments. On a short and long term evolutionary scale, within a species and in families within bacterial orders, respectively, the cyclic di-GMP signalling network can also rapidly disappear. To investigate variability of the cyclic di-GMP signalling system on various levels will give clues about evolutionary forces and discover novel physiological and metabolic pathways affected by this intriguing second messenger signalling system.

RevDate: 2023-08-03
CmpDate: 2023-08-03

Saritas T (2023)

The use of tissue clearing to study renal transport mechanisms and kidney remodelling.

Current opinion in nephrology and hypertension, 32(5):458-466.

PURPOSE OF REVIEW: Tissue clearing enables examination of biological structures at subcellular resolution in three dimensions. It uncovered the spatial and temporal plasticity of multicellular kidney structures that occur during homeostatic stress. This article will review the recent development in tissue clearing protocols and how it facilitated the study of renal transport mechanisms and remodelling of the kidney.

RECENT FINDINGS: Tissue clearing methods have evolved from primarily labelling proteins in thin tissue or individual organs to visualizing both RNA and protein simultaneously in whole animals or human organs. The use of small antibody fragments and innovative imaging techniques improved immunolabelling and resolution. These advances opened up new avenues for studying organ crosstalk and diseases that affect multiple parts of the organism. Accumulating evidence suggests that tubule remodelling can occur rapidly in response to homeostatic stress or injury, allowing for adjustments in the quantitative expression of renal transporters. Tissue clearing helped to better understand the development of tubule cystogenesis, renal hypertension and salt wasting syndromes, and revealed potential progenitor cells in the kidney.

SUMMARY: The continued evolution and improvement of tissue clearing methods can help to gain deep biological insights into the structure and function of the kidney, which will have clinical implications.

RevDate: 2023-08-07
CmpDate: 2023-08-07

Zare M, Mirhoseini SZ, Ghovvati S, et al (2023)

The constitutively active pSMAD2/3 relatively improves the proliferation of chicken primordial germ cells.

Molecular reproduction and development, 90(6):339-357.

In many multicellular organisms, mature gametes originate from primordial germ cells (PGCs). Improvements in the culture of PGCs are important not only for developmental biology research, but also for preserving endangered species, and for genome editing and transgenic animal technologies. SMAD2/3 appear to be powerful regulators of gene expression; however, their potential positive impact on the regulation of PGC proliferation has not been taken into consideration. Here, the effect of TGF-β signaling as the upstream activator of SMAD2/3 transcription factors was evaluated on chicken PGCs' proliferation. For this, chicken PGCs at stages 26-28 Hamburger-Hamilton were obtained from the embryonic gonadal regions and cultured on different feeders or feeder-free substrates. The results showed that TGF-β signaling agonists (IDE1 and Activin-A) improved PGC proliferation to some extent while treatment with SB431542, the antagonist of TGF-β, disrupted PGCs' proliferation. However, the transfection of PGCs with constitutively active SMAD2/3 (SMAD2/3CA) resulted in improved PGC proliferation for more than 5 weeks. The results confirmed the interactions between overexpressed SMAD2/3CA and pluripotency-associated genes NANOG, OCT4, and SOX2. According to the results, the application of SMAD2/3CA could represent a step toward achieving an efficient expansion of avian PGCs.

RevDate: 2023-07-01
CmpDate: 2023-06-26

Fang H, Sun Q, Zhou J, et al (2023)

m[6]A methylation reader IGF2BP2 activates endothelial cells to promote angiogenesis and metastasis of lung adenocarcinoma.

Molecular cancer, 22(1):99.

BACKGROUND: Lung adenocarcinoma (LUAD) is a common type of lung cancer with a high risk of metastasis, but the exact molecular mechanisms of metastasis are not yet understood.

METHODS: This study acquired single-cell transcriptomics profiling of 11 distal normal lung tissues, 11 primary LUAD tissues, and 4 metastatic LUAD tissues from the GSE131907 dataset. The lung multicellular ecosystems were characterized at a single-cell resolution, and the potential mechanisms underlying angiogenesis and metastasis of LUAD were explored.

RESULTS: We constructed a global single-cell landscape of 93,610 cells from primary and metastatic LUAD and found that IGF2BP2 was specifically expressed both in a LUAD cell subpopulation (termed as LUAD_IGF2BP2), and an endothelial cell subpopulation (termed as En_IGF2BP2). The LUAD_IGF2BP2 subpopulation progressively formed and dominated the ecology of metastatic LUAD during metastatic evolution. IGF2BP2 was preferentially secreted by exosomes in the LUAD_IGF2BP2 subpopulation, which was absorbed by the En_IGF2BP2 subpopulation in the tumor microenvironment. Subsequently, IGF2BP2 improved the RNA stability of FLT4 through m[6]A modification, thereby activating the PI3K-Akt signaling pathway, and eventually promoting angiogenesis and metastasis. Analysis of clinical data showed that IGF2BP2 was linked with poor overall survival and relapse-free survival for LUAD patients.

CONCLUSIONS: Overall, these findings provide a novel insight into the multicellular ecosystems of primary and metastatic LUAD, and demonstrate that a specific LUAD_IGF2BP2 subpopulation is a key orchestrator promoting angiogenesis and metastasis, with implications for the gene regulatory mechanisms of LUAD metastatic evolution, representing themselves as potential antiangiogenic targets.

RevDate: 2023-07-01
CmpDate: 2023-06-22

Caspi Y, Pantazopoulou CK, Prompers JJ, et al (2023)

Why did glutamate, GABA, and melatonin become intercellular signalling molecules in plants?.

eLife, 12:.

Intercellular signalling is an indispensable part of multicellular life. Understanding the commonalities and differences in how signalling molecules function in two remote branches of the tree of life may shed light on the reasons these molecules were originally recruited for intercellular signalling. Here we review the plant function of three highly studied animal intercellular signalling molecules, namely glutamate, γ-aminobutyric acid (GABA), and melatonin. By considering both their signalling function in plants and their broader physiological function, we suggest that molecules with an original function as key metabolites or active participants in reactive ion species scavenging have a high chance of becoming intercellular signalling molecules. Naturally, the evolution of machinery to transduce a message across the plasma membrane is necessary. This fact is demonstrated by three other well-studied animal intercellular signalling molecules, namely serotonin, dopamine, and acetylcholine, for which there is currently no evidence that they act as intercellular signalling molecules in plants.

RevDate: 2023-06-19
CmpDate: 2023-06-19

Chavhan Y, Dey S, PA Lind (2023)

Bacteria evolve macroscopic multicellularity by the genetic assimilation of phenotypically plastic cell clustering.

Nature communications, 14(1):3555.

The evolutionary transition from unicellularity to multicellularity was a key innovation in the history of life. Experimental evolution is an important tool to study the formation of undifferentiated cellular clusters, the likely first step of this transition. Although multicellularity first evolved in bacteria, previous experimental evolution research has primarily used eukaryotes. Moreover, it focuses on mutationally driven (and not environmentally induced) phenotypes. Here we show that both Gram-negative and Gram-positive bacteria exhibit phenotypically plastic (i.e., environmentally induced) cell clustering. Under high salinity, they form elongated clusters of ~ 2 cm. However, under habitual salinity, the clusters disintegrate and grow planktonically. We used experimental evolution with Escherichia coli to show that such clustering can be assimilated genetically: the evolved bacteria inherently grow as macroscopic multicellular clusters, even without environmental induction. Highly parallel mutations in genes linked to cell wall assembly formed the genomic basis of assimilated multicellularity. While the wildtype also showed cell shape plasticity across high versus low salinity, it was either assimilated or reversed after evolution. Interestingly, a single mutation could genetically assimilate multicellularity by modulating plasticity at multiple levels of organization. Taken together, we show that phenotypic plasticity can prime bacteria for evolving undifferentiated macroscopic multicellularity.

RevDate: 2023-07-18
CmpDate: 2023-07-11

Jacob MS (2023)

Toward a Bio-Organon: A model of interdependence between energy, information and knowledge in living systems.

Bio Systems, 230:104939.

What is an organism? In the absence of a fundamental biological definition, what constitutes a living organism, whether it is a unicellular microbe, a multicellular being or a multi-organismal society, remains an open question. New models of living systems are needed to address the scale of this question, with implications for the relationship between humanity and planetary ecology. Here we develop a generic model of an organism that can be applied across multiple scales and through major evolutionary transitions to form a toolkit, or bio-organon, for theoretical studies of planetary-wide physiology. The tool identifies the following core organismic principles that cut across spatial scale: (1) evolvability through self-knowledge, (2) entanglement between energy and information, and (3) extrasomatic "technology" to scaffold increases in spatial scale. Living systems are generally defined by their ability to self-sustain against entropic forces of degradation. Life "knows" how to survive from the inside, not from its genetic code alone, but by utilizing this code through dynamically embodied and functionally specialized flows of information and energy. That is, entangled metabolic and communication networks bring encoded knowledge to life in order to sustain life. However, knowledge is itself evolved and is evolving. The functional coupling between knowledge, energy and information has ancient origins, enabling the original, cellular "biotechnology," and cumulative evolutionary creativity in biochemical products and forms. Cellular biotechnology also enabled the nesting of specialized cells into multicellular organisms. This nested organismal hierarchy can be extended further, suggesting that an organism of organisms, or a human "superorganism," is not only possible, but in keeping with evolutionary trends.

RevDate: 2023-06-15
CmpDate: 2023-06-09

Zhang F, Ji Q, Chaturvedi J, et al (2023)

Human SAMD9 is a poxvirus-activatable anticodon nuclease inhibiting codon-specific protein synthesis.

Science advances, 9(23):eadh8502.

As a defense strategy against viruses or competitors, some microbes use anticodon nucleases (ACNases) to deplete essential tRNAs, effectively halting global protein synthesis. However, this mechanism has not been observed in multicellular eukaryotes. Here, we report that human SAMD9 is an ACNase that specifically cleaves phenylalanine tRNA (tRNA[Phe]), resulting in codon-specific ribosomal pausing and stress signaling. While SAMD9 ACNase activity is normally latent in cells, it can be activated by poxvirus infection or rendered constitutively active by SAMD9 mutations associated with various human disorders, revealing tRNA[Phe] depletion as an antiviral mechanism and a pathogenic condition in SAMD9 disorders. We identified the N-terminal effector domain of SAMD9 as the ACNase, with substrate specificity primarily determined by a eukaryotic tRNA[Phe]-specific 2'-O-methylation at the wobble position, making virtually all eukaryotic tRNA[Phe] susceptible to SAMD9 cleavage. Notably, the structure and substrate specificity of SAMD9 ACNase differ from known microbial ACNases, suggesting convergent evolution of a common immune defense strategy targeting tRNAs.

RevDate: 2023-06-27
CmpDate: 2023-06-20

Lamolle G, Simón D, Iriarte A, et al (2023)

Main Factors Shaping Amino Acid Usage Across Evolution.

Journal of molecular evolution, 91(4):382-390.

The standard genetic code determines that in most species, including viruses, there are 20 amino acids that are coded by 61 codons, while the other three codons are stop triplets. Considering the whole proteome each species features its own amino acid frequencies, given the slow rate of change, closely related species display similar GC content and amino acids usage. In contrast, distantly related species display different amino acid frequencies. Furthermore, within certain multicellular species, as mammals, intragenomic differences in the usage of amino acids are evident. In this communication, we shall summarize some of the most prominent and well-established factors that determine the differences found in the amino acid usage, both across evolution and intragenomically.

RevDate: 2023-06-12
CmpDate: 2023-06-05

Galand PE, Ruscheweyh HJ, Salazar G, et al (2023)

Diversity of the Pacific Ocean coral reef microbiome.

Nature communications, 14(1):3039.

Coral reefs are among the most diverse ecosystems on Earth. They support high biodiversity of multicellular organisms that strongly rely on associated microorganisms for health and nutrition. However, the extent of the coral reef microbiome diversity and its distribution at the oceanic basin-scale remains to be explored. Here, we systematically sampled 3 coral morphotypes, 2 fish species, and planktonic communities in 99 reefs from 32 islands across the Pacific Ocean, to assess reef microbiome composition and biogeography. We show a very large richness of reef microorganisms compared to other environments, which extrapolated to all fishes and corals of the Pacific, approximates the current estimated total prokaryotic diversity for the entire Earth. Microbial communities vary among and within the 3 animal biomes (coral, fish, plankton), and geographically. For corals, the cross-ocean patterns of diversity are different from those known for other multicellular organisms. Within each coral morphotype, community composition is always determined by geographic distance first, both at the island and across ocean scale, and then by environment. Our unprecedented sampling effort of coral reef microbiomes, as part of the Tara Pacific expedition, provides new insight into the global microbial diversity, the factors driving their distribution, and the biocomplexity of reef ecosystems.

RevDate: 2023-06-20
CmpDate: 2023-06-15

Blomme J, Wichard T, Jacobs TB, et al (2023)

Ulva: An emerging green seaweed model for systems biology.

Journal of phycology, 59(3):433-440.

Green seaweeds exhibit a wide range of morphologies and occupy various ecological niches, spanning from freshwater to marine and terrestrial habitats. These organisms, which predominantly belong to the class Ulvophyceae, showcase a remarkable instance of parallel evolution toward complex multicellularity and macroscopic thalli in the Viridiplantae lineage. Within the green seaweeds, several Ulva species ("sea lettuce") are model organisms for studying carbon assimilation, interactions with bacteria, life cycle progression, and morphogenesis. Ulva species are also notorious for their fast growth and capacity to dominate nutrient-rich, anthropogenically disturbed coastal ecosystems during "green tide" blooms. From an economic perspective, Ulva has garnered increasing attention as a promising feedstock for the production of food, feed, and biobased products, also as a means of removing excess nutrients from the environment. We propose that Ulva is poised to further develop as a model in green seaweed research. In this perspective, we focus explicitly on Ulva mutabilis/compressa as a model species and highlight the molecular data and tools that are currently available or in development. We discuss several areas that will benefit from future research or where exciting new developments have been reported in other Ulva species.

RevDate: 2023-07-04
CmpDate: 2023-06-07

Jiang P, Kreitman M, J Reinitz (2023)

The effect of mutational robustness on the evolvability of multicellular organisms and eukaryotic cells.

Journal of evolutionary biology, 36(6):906-924.

Canalization involves mutational robustness, the lack of phenotypic change as a result of genetic mutations. Given the large divergence in phenotype across species, understanding the relationship between high robustness and evolvability has been of interest to both theorists and experimentalists. Although canalization was originally proposed in the context of multicellular organisms, the effect of multicellularity and other classes of hierarchical organization on evolvability has not been considered by theoreticians. We address this issue using a Boolean population model with explicit representation of an environment in which individuals with explicit genotype and a hierarchical phenotype representing multicellularity evolve. Robustness is described by a single real number between zero and one which emerges from the genotype-phenotype map. We find that high robustness is favoured in constant environments, and lower robustness is favoured after environmental change. Multicellularity and hierarchical organization severely constrain robustness: peak evolvability occurs at an absolute level of robustness of about 0.99 compared with values of about 0.5 in a classical neutral network model. These constraints result in a sharp peak of evolvability in which the maximum is set by the fact that the fixation of adaptive mutations becomes more improbable as robustness decreases. When robustness is put under genetic control, robustness levels leading to maximum evolvability are selected for, but maximal relative fitness appears to require recombination.

RevDate: 2023-07-18
CmpDate: 2023-07-07

Hoch NC (2023)

Tissue Specificity of DNA Damage and Repair.

Physiology (Bethesda, Md.), 38(5):0.

DNA is a remarkable biochemical macromolecule tasked with storing the genetic information that instructs life on planet Earth. However, its inherent chemical instability within the cellular milieu is incompatible with the accurate transmission of genetic information to subsequent generations. Therefore, biochemical pathways that continuously survey and repair DNA are essential to sustain life, and the fundamental mechanisms by which different DNA lesions are repaired have remained well conserved throughout evolution. Nonetheless, the emergence of multicellular organisms led to profound differences in cellular context and physiology, leading to large variations in the predominant sources of DNA damage between different cell types and in the relative contribution of different DNA repair pathways toward genome maintenance in different tissues. While we continue to make large strides into understanding how individual DNA repair mechanisms operate on a molecular level, much less attention is given to these cell type-specific differences. This short review aims to provide a broad overview of DNA damage and repair mechanisms to nonspecialists and to highlight some fundamental open questions in tissue and cell-type-specificity of these processes, which may have profound implications for our understanding of important pathophysiological processes such as cancer, neurodegeneration, and aging.

RevDate: 2023-06-21
CmpDate: 2023-05-31

McCourt RM, Lewis LA, Strother PK, et al (2023)

Green land: Multiple perspectives on green algal evolution and the earliest land plants.

American journal of botany, 110(5):e16175.

Green plants, broadly defined as green algae and the land plants (together, Viridiplantae), constitute the primary eukaryotic lineage that successfully colonized Earth's emergent landscape. Members of various clades of green plants have independently made the transition from fully aquatic to subaerial habitats many times throughout Earth's history. The transition, from unicells or simple filaments to complex multicellular plant bodies with functionally differentiated tissues and organs, was accompanied by innovations built upon a genetic and phenotypic toolkit that have served aquatic green phototrophs successfully for at least a billion years. These innovations opened an enormous array of new, drier places to live on the planet and resulted in a huge diversity of land plants that have dominated terrestrial ecosystems over the past 500 million years. This review examines the greening of the land from several perspectives, from paleontology to phylogenomics, to water stress responses and the genetic toolkit shared by green algae and plants, to the genomic evolution of the sporophyte generation. We summarize advances on disparate fronts in elucidating this important event in the evolution of the biosphere and the lacunae in our understanding of it. We present the process not as a step-by-step advancement from primitive green cells to an inevitable success of embryophytes, but rather as a process of adaptations and exaptations that allowed multiple clades of green plants, with various combinations of morphological and physiological terrestrialized traits, to become diverse and successful inhabitants of the land habitats of Earth.

RevDate: 2023-05-26

Wu N, Wei L, Zhu Z, et al (2023)

Innovative insights into extrachromosomal circular DNAs in gynecologic tumors and reproduction.

Protein & cell pii:7180341 [Epub ahead of print].

Originating but free from chromosomal DNA, extrachromosomal circular DNAs (eccDNAs) are organized in circular form and have long been found in unicellular and multicellular eukaryotes. Their biogenesis and function are poorly understood as they are characterized by sequence homology with linear DNA, for which few detection methods are available. Recent advances in high-throughput sequencing technologies have revealed that eccDNAs play crucial roles in tumor formation, evolution, and drug resistance as well as aging, genomic diversity, and other biological processes, bringing it back to the research hotspot. Several mechanisms of eccDNA formation have been proposed, including the breakage-fusion-bridge (BFB) and translocation-deletion-amplification models. Gynecologic tumors and disorders of embryonic and fetal development are major threats to human reproductive health. The roles of eccDNAs in these pathological processes have been partially elucidated since the first discovery of eccDNA in pig sperm and the double minutes in ovarian cancer ascites. The present review summarized the research history, biogenesis, and currently available detection and analytical methods for eccDNAs and clarified their functions in gynecologic tumors and reproduction. We also proposed the application of eccDNAs as drug targets and liquid biopsy markers for prenatal diagnosis and the early detection, prognosis, and treatment of gynecologic tumors. This review lays theoretical foundations for future investigations into the complex regulatory networks of eccDNAs in vital physiological and pathological processes.

RevDate: 2023-05-25

Hengge R, Pruteanu M, Stülke J, et al (2023)

Recent advances and perspectives in nucleotide second messenger signaling in bacteria.

microLife, 4:uqad015.

Nucleotide second messengers act as intracellular 'secondary' signals that represent environmental or cellular cues, i.e. the 'primary' signals. As such, they are linking sensory input with regulatory output in all living cells. The amazing physiological versatility, the mechanistic diversity of second messenger synthesis, degradation, and action as well as the high level of integration of second messenger pathways and networks in prokaryotes has only recently become apparent. In these networks, specific second messengers play conserved general roles. Thus, (p)ppGpp coordinates growth and survival in response to nutrient availability and various stresses, while c-di-GMP is the nucleotide signaling molecule to orchestrate bacterial adhesion and multicellularity. c-di-AMP links osmotic balance and metabolism and that it does so even in Archaea may suggest a very early evolutionary origin of second messenger signaling. Many of the enzymes that make or break second messengers show complex sensory domain architectures, which allow multisignal integration. The multiplicity of c-di-GMP-related enzymes in many species has led to the discovery that bacterial cells are even able to use the same freely diffusible second messenger in local signaling pathways that can act in parallel without cross-talking. On the other hand, signaling pathways operating with different nucleotides can intersect in elaborate signaling networks. Apart from the small number of common signaling nucleotides that bacteria use for controlling their cellular "business," diverse nucleotides were recently found to play very specific roles in phage defense. Furthermore, these systems represent the phylogenetic ancestors of cyclic nucleotide-activated immune signaling in eukaryotes.

RevDate: 2023-06-13
CmpDate: 2023-05-25

Lipińska-Zubrycka L, Grochowski M, Bähler J, et al (2023)

Pervasive mRNA uridylation in fission yeast is catalysed by both Cid1 and Cid16 terminal uridyltransferases.

PloS one, 18(5):e0285576.

Messenger RNA uridylation is pervasive and conserved among eukaryotes, but the consequences of this modification for mRNA fate are still under debate. Utilising a simple model organism to study uridylation may facilitate efforts to understand the cellular function of this process. Here we demonstrate that uridylation can be detected using simple bioinformatics approach. We utilise it to unravel widespread transcript uridylation in fission yeast and demonstrate the contribution of both Cid1 and Cid16, the only two annotated terminal uridyltransferases (TUT-ases) in this yeast. To detect uridylation in transcriptome data, we used a RNA-sequencing (RNA-seq) library preparation protocol involving initial linker ligation to fragmented RNA-an approach borrowed from small RNA sequencing that was commonly used in older RNA-seq protocols. We next explored the data to detect uridylation marks. Our analysis show that uridylation in yeast is pervasive, similarly to the one in multicellular organisms. Importantly, our results confirm the role of the cytoplasmic uridyltransferase Cid1 as the primary uridylation catalyst. However, we also observed an auxiliary role of the second uridyltransferase, Cid16. Thus both fission yeast uridyltransferases are involved in mRNA uridylation. Intriguingly, we found no physiological phenotype of the single and double deletion mutants of cid1 and cid16 and only minimal impact of uridylation on steady-state mRNA levels. Our work establishes fission yeast as a potent model to study uridylation in a simple eukaryote, and we demonstrate that it is possible to detect uridylation marks in RNA-seq data without the need for specific methodologies.

RevDate: 2023-07-01
CmpDate: 2023-06-26

Gmiter D, Pacak I, Nawrot S, et al (2023)

Genomes comparison of two Proteus mirabilis clones showing varied swarming ability.

Molecular biology reports, 50(7):5817-5826.

BACKGROUND: Proteus mirabilis is a Gram-negative bacteria most noted for its involvement with catheter-associated urinary tract infections. It is also known for its multicellular migration over solid surfaces, referred to as 'swarming motility'. Here we analyzed the genomic sequences of two P. mirabilis isolates, designated K38 and K39, which exhibit varied swarming ability.

METHODS AND RESULTS: The isolates genomes were sequenced using Illumina NextSeq sequencer, resulting in about 3.94 Mbp, with a GC content of 38.6%, genomes. Genomes were subjected for in silico comparative investigation. We revealed that, despite a difference in swarming motility, the isolates showed high genomic relatedness (up to 100% ANI similarity), suggesting that one of the isolates probably originated from the other.

CONCLUSIONS: The genomic sequences will allow us to investigate the mechanism driving this intriguing phenotypic heterogeneity between closely related P. mirabilis isolates. Phenotypic heterogeneity is an adaptive strategy of bacterial cells to several environmental pressures. It is also an important factor related to their pathogenesis. Therefore, the availability of these genomic sequences will facilitate studies that focus on the host-pathogen interactions during catheter-associated urinary tract infections.

RevDate: 2023-06-15
CmpDate: 2023-06-15

Fields C, M Levin (2023)

Regulative development as a model for origin of life and artificial life studies.

Bio Systems, 229:104927.

Using the formal framework of the Free Energy Principle, we show how generic thermodynamic requirements on bidirectional information exchange between a system and its environment can generate complexity. This leads to the emergence of hierarchical computational architectures in systems that operate sufficiently far from thermal equilibrium. In this setting, the environment of any system increases its ability to predict system behavior by "engineering" the system towards increased morphological complexity and hence larger-scale, more macroscopic behaviors. When seen in this light, regulative development becomes an environmentally-driven process in which "parts" are assembled to produce a system with predictable behavior. We suggest on this basis that life is thermodynamically favorable and that, when designing artificial living systems, human engineers are acting like a generic "environment".

RevDate: 2023-05-18

Sobala ŁF (2023)

Evolution and phylogenetic distribution of endo-α-mannosidase.

Glycobiology pii:7171919 [Epub ahead of print].

While glycans underlie many biological processes, such as protein folding, cell adhesion and cell-cell recognition, deep evolution of glycosylation machinery remains an understudied topic. N-linked glycosylation is a conserved process in which mannosidases are key trimming enzymes. One of them is the glycoprotein endo-α-1,2-mannosidase which participates in the initial trimming of mannose moieties from an N-linked glycan inside the cis-Golgi. It is unique as the only endo-acting mannosidase found in this organelle. Relatively little is known about its origins and evolutionary history; so far it was reported to occur only in vertebrates. In this work, a taxon-rich bioinformatic survey to unravel the evolutionary history of this enzyme, including all major eukaryotic clades and a wide representation of animals, is presented. The endomannosidase was found to be more widely distributed in animals and other eukaryotes. The protein motif changes in context of the canonical animal enzyme were tracked. Additionally, the data show the two canonical vertebrate endomannosidase genes, MANEA and MANEAL, arose at the second round of the two vertebrate genome duplications and one more vertebrate paralog, CMANEAL, is uncovered. Finally, a framework where N-glycosylation co-evolved with complex multicellularity is described. A better understanding of the evolution of core glycosylation pathways is pivotal to understanding biology of eukaryotes in general, and the Golgi apparatus in particular. This systematic analysis of the endomannosidase evolution is one step towards this goal.

RevDate: 2023-06-05
CmpDate: 2023-06-05

Fernandes J (2023)

Virus-Induced Lysis of Tumor and Other Pathogenic Unicellular Entities and Its Potential to Treat Leishmaniasis.

DNA and cell biology, 42(6):305-314.

This article is focused on the main pathways used by viruses to achieve infection and lysis of unicellular eukaryotes described as pathogenic for multicellular organisms. In light of the recent discussions on how tumor cells exhibit unicellular behavior, highly malignant cells can be considered as another unicellular pathogenic entity, but with endogenous origin. Thus, a comparative panel of viral lysis of exogenous pathogenic unicellular eukaryotes such as Acanthamoeba sp., yeast, and tumors is presented. The important intracellular parasite Leishmania sp is also presented, which, in contrast, has its virulence improved by viral infections. The possible exploitation of viral-mediated eukaryotic cell lysis to overcome infections of Leishmania sp is discussed.

RevDate: 2023-05-17
CmpDate: 2023-05-16

Kaucka M (2023)

Cis-regulatory landscapes in the evolution and development of the mammalian skull.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 378(1880):20220079.

Extensive morphological variation found in mammals reflects the wide spectrum of their ecological adaptations. The highest morphological diversity is present in the craniofacial region, where geometry is mainly dictated by the bony skull. Mammalian craniofacial development represents complex multistep processes governed by numerous conserved genes that require precise spatio-temporal control. A central question in contemporary evolutionary biology is how a defined set of conserved genes can orchestrate formation of fundamentally different structures, and therefore how morphological variability arises. In principle, differential gene expression patterns during development are the source of morphological variation. With the emergence of multicellular organisms, precise regulation of gene expression in time and space is attributed to cis-regulatory elements. These elements contribute to higher-order chromatin structure and together with trans-acting factors control transcriptional landscapes that underlie intricate morphogenetic processes. Consequently, divergence in cis-regulation is believed to rewire existing gene regulatory networks and form the core of morphological evolution. This review outlines the fundamental principles of the genetic code and genomic regulation interplay during development. Recent work that deepened our comprehension of cis-regulatory element origin, divergence and function is presented here to illustrate the state-of-the-art research that uncovered the principles of morphological novelty. This article is part of the theme issue 'The mammalian skull: development, structure and function'.

RevDate: 2023-05-15
CmpDate: 2023-05-15

Suwannachuen N, Leetanasaksakul K, Roytrakul S, et al (2023)

Palmelloid Formation and Cell Aggregation Are Essential Mechanisms for High Light Tolerance in a Natural Strain of Chlamydomonas reinhardtii.

International journal of molecular sciences, 24(9):.

Photosynthetic organisms, such as higher plants and algae, require light to survive. However, an excessive amount of light can be harmful due to the production of reactive oxygen species (ROS), which cause cell damage and, if it is not effectively regulated, cell death. The study of plants' responses to light can aid in the development of methods to improve plants' growth and productivity. Due to the multicellular nature of plants, there may be variations in the results based on plant age and tissue type. Chlamydomonas reinhardtii, a unicellular green alga, has also been used as a model organism to study photosynthesis and photoprotection. Nonetheless, the majority of the research has been conducted with strains that have been consistently utilized in laboratories and originated from the same source. Despite the availability of many field isolates of this species, very few studies have compared the light responses of field isolates. This study examined the responses of two field isolates of Chlamydomonas to high light stress. The light-tolerant strain, CC-4414, managed reactive oxygen species (ROS) slightly better than the sensitive strain, CC-2344, did. The proteomic data of cells subjected to high light revealed cellular modifications of the light-tolerant strain toward membrane proteins. The morphology of cells under light stress revealed that this strain utilized the formation of palmelloid structures and cell aggregation to shield cells from excessive light. As indicated by proteome data, morphological modifications occur simultaneously with the increase in protein degradation and autophagy. By protecting cells from stress, cells are able to continue to upregulate ROS management mechanisms and prevent cell death. This is the first report of palmelloid formation in Chlamydomonas under high light stress.

RevDate: 2023-05-15
CmpDate: 2023-05-15

Foo YZ, Lagisz M, O'Dea RE, et al (2023)

The influence of immune challenges on the mean and variance in reproductive investment: a meta-analysis of the terminal investment hypothesis.

BMC biology, 21(1):107.

Finding the optimal balance between survival and reproduction is a central puzzle in life-history theory. The terminal investment hypothesis predicts that when individuals encounter a survival threat that compromises future reproductive potential, they will increase immediate reproductive investment to maximise fitness. Despite decades of research on the terminal investment hypothesis, findings remain mixed. We examined the terminal investment hypothesis with a meta-analysis of studies that measured reproductive investment of multicellular iteroparous animals after a non-lethal immune challenge. We had two main aims. The first was to investigate whether individuals, on average, increase reproductive investment in response to an immune threat, as predicted by the terminal investment hypothesis. We also examined whether such responses vary adaptively on factors associated with the amount of reproductive opportunities left (residual reproductive value) in the individuals, as predicted by the terminal investment hypothesis. The second was to provide a quantitative test of a novel prediction based on the dynamic threshold model: that an immune threat increases between-individual variance in reproductive investment. Our results provided some support for our hypotheses. Older individuals, who are expected to have lower residual reproductive values, showed stronger mean terminal investment response than younger individuals. In terms of variance, individuals showed a divergence in responses, leading to an increase in variance. This increase in variance was especially amplified in longer-living species, which was consistent with our prediction that individuals in longer-living species should respond with greater individual variation due to increased phenotypic plasticity. We find little statistical evidence of publication bias. Together, our results highlight the need for a more nuanced view on the terminal investment hypothesis and a greater focus on the factors that drive individual responses.

RevDate: 2023-06-01
CmpDate: 2023-06-01

Bozdag GO, Zamani-Dahaj SA, Day TC, et al (2023)

De novo evolution of macroscopic multicellularity.

Nature, 617(7962):747-754.

While early multicellular lineages necessarily started out as relatively simple groups of cells, little is known about how they became Darwinian entities capable of sustained multicellular evolution[1-3]. Here we investigate this with a multicellularity long-term evolution experiment, selecting for larger group size in the snowflake yeast (Saccharomyces cerevisiae) model system. Given the historical importance of oxygen limitation[4], our ongoing experiment consists of three metabolic treatments[5]-anaerobic, obligately aerobic and mixotrophic yeast. After 600 rounds of selection, snowflake yeast in the anaerobic treatment group evolved to be macroscopic, becoming around 2 × 10[4] times larger (approximately mm scale) and about 10[4]-fold more biophysically tough, while retaining a clonal multicellular life cycle. This occurred through biophysical adaptation-evolution of increasingly elongate cells that initially reduced the strain of cellular packing and then facilitated branch entanglements that enabled groups of cells to stay together even after many cellular bonds fracture. By contrast, snowflake yeast competing for low oxygen[5] remained microscopic, evolving to be only around sixfold larger, underscoring the critical role of oxygen levels in the evolution of multicellular size. Together, this research provides unique insights into an ongoing evolutionary transition in individuality, showing how simple groups of cells overcome fundamental biophysical limitations through gradual, yet sustained, multicellular evolution.

RevDate: 2023-05-13
CmpDate: 2023-05-11

Conlin PL, WC Ratcliff (2023)

Evolution: Understanding the origins of facultative multicellular life cycles.

Current biology : CB, 33(9):R356-R358.

Multicellular organisms exhibit a fascinating diversity of life cycles, but little is known about the factors governing life-cycle evolution. New studies of wild yeast and cyanobacteria provide insight into how and why facultative multicellular life cycles arise.

RevDate: 2023-05-20
CmpDate: 2023-05-10

Cooney DB, Levin SA, Mori Y, et al (2023)

Evolutionary dynamics within and among competing groups.

Proceedings of the National Academy of Sciences of the United States of America, 120(20):e2216186120.

Biological and social systems are structured at multiple scales, and the incentives of individuals who interact in a group may diverge from the collective incentive of the group as a whole. Mechanisms to resolve this tension are responsible for profound transitions in evolutionary history, including the origin of cellular life, multicellular life, and even societies. Here, we synthesize a growing literature that extends evolutionary game theory to describe multilevel evolutionary dynamics, using nested birth-death processes and partial differential equations to model natural selection acting on competition within and among groups of individuals. We analyze how mechanisms known to promote cooperation within a single group-including assortment, reciprocity, and population structure-alter evolutionary outcomes in the presence of competition among groups. We find that population structures most conducive to cooperation in multiscale systems can differ from those most conducive within a single group. Likewise, for competitive interactions with a continuous range of strategies we find that among-group selection may fail to produce socially optimal outcomes, but it can nonetheless produce second-best solutions that balance individual incentives to defect with the collective incentives for cooperation. We conclude by describing the broad applicability of multiscale evolutionary models to problems ranging from the production of diffusible metabolites in microbes to the management of common-pool resources in human societies.

RevDate: 2023-06-12
CmpDate: 2023-06-12

Krasovec M, Hoshino M, Zheng M, et al (2023)

Low Spontaneous Mutation Rate in Complex Multicellular Eukaryotes with a Haploid-Diploid Life Cycle.

Molecular biology and evolution, 40(6):.

The spontaneous mutation rate µ is a crucial parameter to understand evolution and biodiversity. Mutation rates are highly variable across species, suggesting that µ is susceptible to selection and drift and that species life cycle and life history may impact its evolution. In particular, asexual reproduction and haploid selection are expected to affect the mutation rate, but very little empirical data are available to test this expectation. Here, we sequence 30 genomes of a parent-offspring pedigree in the model brown alga Ectocarpus sp.7, and 137 genomes of an interspecific cross of the closely related brown alga Scytosiphon to have access to the spontaneous mutation rate of representative organisms of a complex multicellular eukaryotic lineage outside animals and plants, and to evaluate the potential impact of life cycle on the mutation rate. Brown algae alternate between a haploid and a diploid stage, both multicellular and free living, and utilize both sexual and asexual reproduction. They are, therefore, excellent models to empirically test expectations of the effect of asexual reproduction and haploid selection on mutation rate evolution. We estimate that Ectocarpus has a base substitution rate of µbs = 4.07 × 10-10 per site per generation, whereas the Scytosiphon interspecific cross had µbs = 1.22 × 10-9. Overall, our estimations suggest that these brown algae, despite being multicellular complex eukaryotes, have unusually low mutation rates. In Ectocarpus, effective population size (Ne) could not entirely explain the low µbs. We propose that the haploid-diploid life cycle, combined with extensive asexual reproduction, may be additional key drivers of the mutation rate in these organisms.

RevDate: 2023-05-02
CmpDate: 2023-05-01

Grochau-Wright ZI, Nedelcu AM, RE Michod (2023)

The Genetics of Fitness Reorganization during the Transition to Multicellularity: The Volvocine regA-like Family as a Model.

Genes, 14(4):.

The evolutionary transition from single-celled to multicellular individuality requires organismal fitness to shift from the cell level to a cell group. This reorganization of fitness occurs by re-allocating the two components of fitness, survival and reproduction, between two specialized cell types in the multicellular group: soma and germ, respectively. How does the genetic basis for such fitness reorganization evolve? One possible mechanism is the co-option of life history genes present in the unicellular ancestors of a multicellular lineage. For instance, single-celled organisms must regulate their investment in survival and reproduction in response to environmental changes, particularly decreasing reproduction to ensure survival under stress. Such stress response life history genes can provide the genetic basis for the evolution of cellular differentiation in multicellular lineages. The regA-like gene family in the volvocine green algal lineage provides an excellent model system to study how this co-option can occur. We discuss the origin and evolution of the volvocine regA-like gene family, including regA-the gene that controls somatic cell development in the model organism Volvox carteri. We hypothesize that the co-option of life history trade-off genes is a general mechanism involved in the transition to multicellular individuality, making volvocine algae and the regA-like family a useful template for similar investigations in other lineages.

RevDate: 2023-05-02
CmpDate: 2023-05-01

Casotti MC, Meira DD, Zetum ASS, et al (2023)

Computational Biology Helps Understand How Polyploid Giant Cancer Cells Drive Tumor Success.

Genes, 14(4):.

Precision and organization govern the cell cycle, ensuring normal proliferation. However, some cells may undergo abnormal cell divisions (neosis) or variations of mitotic cycles (endopolyploidy). Consequently, the formation of polyploid giant cancer cells (PGCCs), critical for tumor survival, resistance, and immortalization, can occur. Newly formed cells end up accessing numerous multicellular and unicellular programs that enable metastasis, drug resistance, tumor recurrence, and self-renewal or diverse clone formation. An integrative literature review was carried out, searching articles in several sites, including: PUBMED, NCBI-PMC, and Google Academic, published in English, indexed in referenced databases and without a publication time filter, but prioritizing articles from the last 3 years, to answer the following questions: (i) "What is the current knowledge about polyploidy in tumors?"; (ii) "What are the applications of computational studies for the understanding of cancer polyploidy?"; and (iii) "How do PGCCs contribute to tumorigenesis?"

RevDate: 2023-05-04
CmpDate: 2023-04-27

Colgren J, P Burkhardt (2023)

Evolution: Was the nuclear-to-cytoplasmic ratio a key factor in the origin of animal multicellularity?.

Current biology : CB, 33(8):R298-R300.

The ichthyosporean Sphaeroforma arctica, a protist closely related to animals, displays coenocytic development followed by cellularization and cell release. A new study reveals that the nuclear-to-cytoplasmic ratio drives cellularization in these fascinating organisms.

RevDate: 2023-05-16
CmpDate: 2023-04-26

Stéger A, M Palmgren (2023)

Hypothesis paper: the development of a regulatory layer in P2B autoinhibited Ca[2+]-ATPases may have facilitated plant terrestrialization and animal multicellularization.

Plant signaling & behavior, 18(1):2204284.

With the appearance of plants and animals, new challenges emerged. These multicellular eukaryotes had to solve for example the difficulties of multifaceted communication between cells and adaptation to new habitats. In this paper, we are looking for one piece of the puzzle that made the development of complex multicellular eukaryotes possible with a focus on regulation of P2B autoinhibited Ca[2+]-ATPases. P2B ATPases pump Ca[2+] out of the cytosol at the expense of ATP hydrolysis, and thereby maintain a steep gradient between the extra- and intracytosolic compartments which is utilized for Ca[2+]-mediated rapid cell signaling. The activity of these enzymes is regulated by a calmodulin (CaM)-responsive autoinhibitory region, which can be located in either termini of the protein, at the C-terminus in animals and at the N-terminus in plants. When the cytoplasmic Ca[2+] level reaches a threshold, the CaM/Ca[2+] complex binds to a calmodulin-binding domain (CaMBD) in the autoinhibitor, which leads to the upregulation of pump activity. In animals, protein activity is also controlled by acidic phospholipids that bind to a cytosolic portion of the pump. Here, we analyze the appearance of CaMBDs and the phospholipid-activating sequence and show that their evolution in animals and plants was independent. Furthermore, we hypothesize that different causes may have initiated the appearance of these regulatory layers: in animals, it is linked to the appearance of multicellularity, while in plants it co-occurs with their water-to-land transition.

RevDate: 2023-05-10
CmpDate: 2023-04-26

Ros-Rocher N, Kidner RQ, Gerdt C, et al (2023)

Chemical factors induce aggregative multicellularity in a close unicellular relative of animals.

Proceedings of the National Academy of Sciences of the United States of America, 120(18):e2216668120.

Regulated cellular aggregation is an essential process for development and healing in many animal tissues. In some animals and a few distantly related unicellular species, cellular aggregation is regulated by diffusible chemical cues. However, it is unclear whether regulated cellular aggregation was part of the life cycles of the first multicellular animals and/or their unicellular ancestors. To fill this gap, we investigated the triggers of cellular aggregation in one of animals' closest unicellular living relatives-the filasterean Capsaspora owczarzaki. We discovered that Capsaspora aggregation is induced by chemical cues, as observed in some of the earliest branching animals and other unicellular species. Specifically, we found that calcium ions and lipids present in lipoproteins function together to induce aggregation of viable Capsaspora cells. We also found that this multicellular stage is reversible as depletion of the cues triggers disaggregation, which can be overcome upon reinduction. Our finding demonstrates that chemically regulated aggregation is important across diverse members of the holozoan clade. Therefore, this phenotype was plausibly integral to the life cycles of the unicellular ancestors of animals.

RevDate: 2023-05-14
CmpDate: 2023-05-08

Kumar T, Sethuraman R, Mitra S, et al (2023)

MultiCens: Multilayer network centrality measures to uncover molecular mediators of tissue-tissue communication.

PLoS computational biology, 19(4):e1011022.

With the evolution of multicellularity, communication among cells in different tissues and organs became pivotal to life. Molecular basis of such communication has long been studied, but genome-wide screens for genes and other biomolecules mediating tissue-tissue signaling are lacking. To systematically identify inter-tissue mediators, we present a novel computational approach MultiCens (Multilayer/Multi-tissue network Centrality measures). Unlike single-layer network methods, MultiCens can distinguish within- vs. across-layer connectivity to quantify the "influence" of any gene in a tissue on a query set of genes of interest in another tissue. MultiCens enjoys theoretical guarantees on convergence and decomposability, and performs well on synthetic benchmarks. On human multi-tissue datasets, MultiCens predicts known and novel genes linked to hormones. MultiCens further reveals shifts in gene network architecture among four brain regions in Alzheimer's disease. MultiCens-prioritized hypotheses from these two diverse applications, and potential future ones like "Multi-tissue-expanded Gene Ontology" analysis, can enable whole-body yet molecular-level systems investigations in humans.

RevDate: 2023-06-05
CmpDate: 2023-06-05

Hashimoto A, Kawamura N, Tarusawa E, et al (2023)

Microglia enable cross-modal plasticity by removing inhibitory synapses.

Cell reports, 42(5):112383.

Cross-modal plasticity is the repurposing of brain regions associated with deprived sensory inputs to improve the capacity of other sensory modalities. The functional mechanisms of cross-modal plasticity can indicate how the brain recovers from various forms of injury and how different sensory modalities are integrated. Here, we demonstrate that rewiring of the microglia-mediated local circuit synapse is crucial for cross-modal plasticity induced by visual deprivation (monocular deprivation [MD]). MD relieves the usual inhibition of functional connectivity between the somatosensory cortex and secondary lateral visual cortex (V2L). This results in enhanced excitatory responses in V2L neurons during whisker stimulation and a greater capacity for vibrissae sensory discrimination. The enhanced cross-modal response is mediated by selective removal of inhibitory synapse terminals on pyramidal neurons by the microglia in the V2L via matrix metalloproteinase 9 signaling. Our results provide insights into how cortical circuits integrate different inputs to functionally compensate for neuronal damage.

RevDate: 2023-05-07
CmpDate: 2023-05-05

Isaksson H, Brännström Å, E Libby (2023)

Minor variations in multicellular life cycles have major effects on adaptation.

PLoS computational biology, 19(4):e1010698.

Multicellularity has evolved several independent times over the past hundreds of millions of years and given rise to a wide diversity of complex life. Recent studies have found that large differences in the fundamental structure of early multicellular life cycles can affect fitness and influence multicellular adaptation. Yet, there is an underlying assumption that at some scale or categorization multicellular life cycles are similar in terms of their adaptive potential. Here, we consider this possibility by exploring adaptation in a class of simple multicellular life cycles of filamentous organisms that only differ in one respect, how many daughter filaments are produced. We use mathematical models and evolutionary simulations to show that despite the similarities, qualitatively different mutations fix. In particular, we find that mutations with a tradeoff between cell growth and group survival, i.e. "selfish" or "altruistic" traits, spread differently. Specifically, altruistic mutations more readily spread in life cycles that produce few daughters while in life cycles producing many daughters either type of mutation can spread depending on the environment. Our results show that subtle changes in multicellular life cycles can fundamentally alter adaptation.

RevDate: 2023-06-12
CmpDate: 2023-06-12

Cornwallis CK, Svensson-Coelho M, Lindh M, et al (2023)

Single-cell adaptations shape evolutionary transitions to multicellularity in green algae.

Nature ecology & evolution, 7(6):889-902.

The evolution of multicellular life has played a pivotal role in shaping biological diversity. However, we know surprisingly little about the natural environmental conditions that favour the formation of multicellular groups. Here we experimentally examine how key environmental factors (predation, nitrogen and water turbulence) combine to influence multicellular group formation in 35 wild unicellular green algae strains (19 Chlorophyta species). All environmental factors induced the formation of multicellular groups (more than four cells), but there was no evidence this was adaptive, as multicellularity (% cells in groups) was not related to population growth rate under any condition. Instead, population growth was related to extracellular matrix (ECM) around single cells and palmelloid formation, a unicellular life-cycle stage where two to four cells are retained within a mother-cell wall after mitosis. ECM production increased with nitrogen levels resulting in more cells being in palmelloids and higher rates of multicellular group formation. Examining the distribution of 332 algae species across 478 lakes monitored over 55 years, showed that ECM and nitrogen availability also predicted patterns of obligate multicellularity in nature. Our results highlight that adaptations of unicellular organisms to cope with environmental challenges may be key to understanding evolutionary routes to multicellular life.

RevDate: 2023-05-16
CmpDate: 2023-05-11

Cadart C, Bartz J, Oaks G, et al (2023)

Polyploidy in Xenopus lowers metabolic rate by decreasing total cell surface area.

Current biology : CB, 33(9):1744-1752.e7.

Although polyploidization is frequent in development, cancer, and evolution, impacts on animal metabolism are poorly understood. In Xenopus frogs, the number of genome copies (ploidy) varies across species and can be manipulated within a species. Here, we show that triploid tadpoles contain fewer, larger cells than diploids and consume oxygen at a lower rate. Drug treatments revealed that the major processes accounting for tadpole energy expenditure include cell proliferation, biosynthesis, and maintenance of plasma membrane potential. While inhibiting cell proliferation did not abolish the oxygen consumption difference between diploids and triploids, treatments that altered cellular biosynthesis or electrical potential did. Combining these results with a simple mathematical framework, we propose that the decrease in total cell surface area lowered production and activity of plasma membrane components including the Na[+]/K[+] ATPase, reducing energy consumption in triploids. Comparison of Xenopus species that evolved through polyploidization revealed that metabolic differences emerged during development when cell size scaled with genome size. Thus, ploidy affects metabolism by altering the cell surface area to volume ratio in a multicellular organism.

RevDate: 2023-04-27
CmpDate: 2023-04-14

Leitner N, Ertl R, Gabner S, et al (2023)

Isolation and Characterization of Novel Canine Osteosarcoma Cell Lines from Chemotherapy-Naïve Patients.

Cells, 12(7):.

The present study aimed to establish novel canine osteosarcoma cell lines (COS3600, COS3600B, COS4074) and characterize the recently described COS4288 cells. The established D-17 cell line served as a reference. Analyzed cell lines differed notably in their biological characteristics. Calculated doubling times were between 22 h for COS3600B and 426 h for COS4074 cells. COS3600B and COS4288 cells produced visible colonies after anchorage-independent growth in soft agar. COS4288 cells were identified as cells with the highest migratory capacity. All cells displayed the ability to invade through an artificial basement membrane matrix. Immunohistochemical analyses revealed the mesenchymal origin of all COS cell lines as well as positive staining for the osteosarcoma-relevant proteins alkaline phosphatase and karyopherin α2. Expression of p53 was confirmed in all tested cell lines. Gene expression analyses of selected genes linked to cellular immune checkpoints (CD270, CD274, CD276), kinase activity (MET, ERBB2), and metastatic potential (MMP-2, MMP-9) as well as selected long non-coding RNA (MALAT1) and microRNAs (miR-9, miR-34a, miR-93) are provided. All tested cell lines were able to grow as multicellular spheroids. In all spheroids except COS4288, calcium deposition was detected by von Kossa staining. We believe that these new cell lines serve as useful biological models for future studies.

RevDate: 2023-04-17
CmpDate: 2023-04-17

Vinogradov AE, OV Anatskaya (2023)

Systemic Alterations of Cancer Cells and Their Boost by Polyploidization: Unicellular Attractor (UCA) Model.

International journal of molecular sciences, 24(7):.

Using meta-analyses, we introduce a unicellular attractor (UCA) model integrating essential features of the 'atavistic reversal', 'cancer attractor', 'somatic mutation', 'genome chaos', and 'tissue organization field' theories. The 'atavistic reversal' theory is taken as a keystone. We propose a possible mechanism of this reversal, its refinement called 'gradual atavism', and evidence for the 'serial atavism' model. We showed the gradual core-to-periphery evolutionary growth of the human interactome resulting in the higher protein interaction density and global interactome centrality in the UC center. In addition, we revealed that UC genes are more actively expressed even in normal cells. The modeling of random walk along protein interaction trajectories demonstrated that random alterations in cellular networks, caused by genetic and epigenetic changes, can result in a further gradual activation of the UC center. These changes can be induced and accelerated by cellular stress that additionally activates UC genes (especially during cell proliferation), because the genes involved in cellular stress response and cell cycle are mostly of UC origin. The functional enrichment analysis showed that cancer cells demonstrate the hyperactivation of energetics and the suppression of multicellular genes involved in communication with the extracellular environment (especially immune surveillance). Collectively, these events can unleash selfish cell behavior aimed at survival at all means. All these changes are boosted by polyploidization. The UCA model may facilitate an understanding of oncogenesis and promote the development of therapeutic strategies.

RevDate: 2023-04-15
CmpDate: 2023-04-14

Li G, Chen L, Pang K, et al (2023)

Tonian carbonaceous compressions indicate that Horodyskia is one of the oldest multicellular and coenocytic macro-organisms.

Communications biology, 6(1):399.

Macrofossils with unambiguous biogenic origin and predating the one-billion-year-old multicellular fossils Bangiomorpha and Proterocladus interpreted as crown-group eukaryotes are quite rare. Horodyskia is one of these few macrofossils, and it extends from the early Mesoproterozoic Era to the terminal Ediacaran Period. The biological interpretation of this enigmatic fossil, however, has been a matter of controversy since its discovery in 1982, largely because there was no evidence for the preservation of organic walls. Here we report new carbonaceous compressions of Horodyskia from the Tonian successions (~950-720 Ma) in North China. The macrofossils herein with bona fide organic walls reinforce the biogenicity of Horodyskia. Aided by the new material, we reconstruct Horodyskia as a colonial organism composed of a chain of organic-walled vesicles that likely represent multinucleated (coenocytic) cells of early eukaryotes. Two species of Horodyskia are differentiated on the basis of vesicle sizes, and their co-existence in the Tonian assemblage provides a link between the Mesoproterozoic (H. moniliformis) and the Ediacaran (H. minor) species. Our study thus provides evidence that eukaryotes have acquired macroscopic size through the combination of coenocytism and colonial multicellularity at least ~1.48 Ga, and highlights an exceptionally long range and morphological stasis of this Proterozoic macrofossils.

RevDate: 2023-06-12
CmpDate: 2023-06-12

Varilla González JD, Macedo Alves F, Bagnatori Sartori ÂL, et al (2023)

Diversity and evolution of leaflet anatomical characters in the Pterocarpus clade (Fabaceae: Papilionoideae).

Journal of plant research, 136(4):453-481.

The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize morphological synapomorphies. This study aimed to identify new synapomorphies for the Pterocarpus clade, to identify characters supporting inter-generic relationships currently resolved only by molecular data and to identify diagnostic characters at the genus and species levels. Subterminal leaflets of the studied genera were selected and analyzed using light and scanning electron microscopy. Ancestral reconstruction was performed using morphological and anatomical characters of 16 genera of the Pterocarpus clade. The convex epidermal relief in the region of the main vein indicated the relationship among all genera of the group. Anchor-like multicellular trichomes are features shared by Brya and Cranocarpus, which are the sister group to the other genera of the clade. Subepidermal layers are features shared by the Centrolobium, Etaballia, Paramachaerium, Pterocarpus and Tipuana genera, and the sclerenchyma sheath in the leaflet margin is reported in the Discolobium, Riedeliella and Platymiscium genera. Bulbous based glandular trichomes and vesicular glandular trichomes are diagnostic at the species level in Centrolobium and Pterocarpus, respectively. The leaflet characters investigated can be useful for the taxonomic delimitation at both the genus and species levels of the Pterocarpus clade. Our dataset provides new synapomorphies, elucidates the inter-generic relationships and reinforces the phylogenetic classification of the Pterocarpus clade resolved by molecular data.

RevDate: 2023-05-05
CmpDate: 2023-05-05

Darras H, Berney C, Hasin S, et al (2023)

Obligate chimerism in male yellow crazy ants.

Science (New York, N.Y.), 380(6640):55-58.

Multicellular organisms typically develop from a single fertilized egg and therefore consist of clonal cells. We report an extraordinary reproductive system in the yellow crazy ant. Males are chimeras of haploid cells from two divergent lineages: R and W. R cells are overrepresented in the males' somatic tissues, whereas W cells are overrepresented in their sperm. Chimerism occurs when parental nuclei bypass syngamy and divide separately within the same egg. When syngamy takes place, the diploid offspring either develops into a queen when the oocyte is fertilized by an R sperm or into a worker when fertilized by a W sperm. This study reveals a mode of reproduction that may be associated with a conflict between lineages to preferentially enter the germ line.

RevDate: 2023-05-15
CmpDate: 2023-05-11

Barrere J, Nanda P, AW Murray (2023)

Alternating selection for dispersal and multicellularity favors regulated life cycles.

Current biology : CB, 33(9):1809-1817.e3.

The evolution of complex multicellularity opened paths to increased morphological diversity and organizational novelty. This transition involved three processes: cells remained attached to one another to form groups, cells within these groups differentiated to perform different tasks, and the groups evolved new reproductive strategies.[1][,][2][,][3][,][4][,][5] Recent experiments identified selective pressures and mutations that can drive the emergence of simple multicellularity and cell differentiation,[6][,][7][,][8][,][9][,][10][,][11] but the evolution of life cycles, particularly how simple multicellular forms reproduce, has been understudied. The selective pressure and mechanisms that produced a regular alternation between single cells and multicellular collectives are still unclear.[12] To probe the factors regulating simple multicellular life cycles, we examined a collection of wild isolates of the budding yeast S. cerevisiae.[12][,][13] We found that all these strains can exist as multicellular clusters, a phenotype that is controlled by the mating-type locus and strongly influenced by the nutritional environment. Inspired by this variation, we engineered inducible dispersal in a multicellular laboratory strain and demonstrated that a regulated life cycle has an advantage over constitutively single-celled or constitutively multicellular life cycles when the environment alternates between favoring intercellular cooperation (a low sucrose concentration) and dispersal (a patchy environment generated by emulsion). Our results suggest that the separation of mother and daughter cells is under selection in wild isolates and is regulated by their genetic composition and the environments they encounter and that alternating patterns of resource availability may have played a role in the evolution of life cycles.

RevDate: 2023-06-02
CmpDate: 2023-05-30

Morehouse BR (2023)

Phage defense origin of animal immunity.

Current opinion in microbiology, 73:102295.

The innate immune system is the first line of defense against microbial pathogens. Many of the features of eukaryotic innate immunity have long been viewed as lineage-specific innovations, evolved to deal with the challenges and peculiarities of multicellular life. However, it has become increasingly apparent that in addition to evolving their own unique antiviral immune strategies, all lifeforms have some shared defense strategies in common. Indeed, critical fixtures of animal innate immunity bear striking resemblance in both structure and function to the multitude of diverse bacteriophage (phage) defense pathways discovered hidden in plain sight within the genomes of bacteria and archaea. This review will highlight many surprising examples of the recently revealed connections between prokaryotic and eukaryotic antiviral immune systems.


ESP Quick Facts

ESP Origins

In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

ESP Support

In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

ESP Rationale

Although the methods of molecular biology can seem almost magical to the uninitiated, the original techniques of classical genetics are readily appreciated by one and all: cross individuals that differ in some inherited trait, collect all of the progeny, score their attributes, and propose mechanisms to explain the patterns of inheritance observed.

ESP Goal

In reading the early works of classical genetics, one is drawn, almost inexorably, into ever more complex models, until molecular explanations begin to seem both necessary and natural. At that point, the tools for understanding genome research are at hand. Assisting readers reach this point was the original goal of The Electronic Scholarly Publishing Project.

ESP Usage

Usage of the site grew rapidly and has remained high. Faculty began to use the site for their assigned readings. Other on-line publishers, ranging from The New York Times to Nature referenced ESP materials in their own publications. Nobel laureates (e.g., Joshua Lederberg) regularly used the site and even wrote to suggest changes and improvements.

ESP Content

When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

ESP Help

Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

ESP Plans

With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

Electronic Scholarly Publishing
961 Red Tail Lane
Bellingham, WA 98226

E-mail: RJR8222 @

Papers in Classical Genetics

The ESP began as an effort to share a handful of key papers from the early days of classical genetics. Now the collection has grown to include hundreds of papers, in full-text format.

Digital Books

Along with papers on classical genetics, ESP offers a collection of full-text digital books, including many works by Darwin (and even a collection of poetry — Chicago Poems by Carl Sandburg).


ESP now offers a much improved and expanded collection of timelines, designed to give the user choice over subject matter and dates.


Biographical information about many key scientists.

Selected Bibliographies

Bibliographies on several topics of potential interest to the ESP community are now being automatically maintained and generated on the ESP site.

ESP Picks from Around the Web (updated 07 JUL 2018 )