Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
24
datasets available to search
ShareScore release 0.9.0
Dataset results
24 results for “social amoeba”
Data and code for Symbiotic bacteria, immune-like sentinel cells, and the response to pathogens in a social amoeba
<p>This repository contains data and code to do the analyses in the paper "Symbiotic bacteria, immune-like sentinel cells, and the response to pathogens in a social amoeba" published in Royal Society Open Science. The paper investigates how infection by <em>Paraburkholderia</em> symbionts affects host <em>Dictyostelium discoideum</em>'s immune function.</p>
Wild Dictyostelium discoideum social amoebae show plastic responses to the presence of nonrelatives during multicellular development
<p>When multiple strains of microbes form social groups, such as the multicellular fruiting bodies of <em>Dictyostelium discoideum</em>, conflict can arise regarding cell fate. Both fixed and plastic differences among strains can contribute to cell fate, and plastic responses may be particularly important if social environments frequently change. We used RNA-sequencing and photographic time series analysis to detect possible conflict-induced plastic differences between wild <em>D. discoideum </em>aggregates formed by single strains compared to mixed pairs of strains (chimeras). We found one hundred and two differentially expressed genes that were enriched for biological processes including cytoskeleton organization and cyclic-AMP response (up-regulated in chimeras), and DNA replication and cell cycle (down-regulated in chimeras). In addition, our data indicate that in reference to a time series of multicellular development in the lab strain AX4, chimeras may be slightly behind clonal aggregates in their development. Finally, phenotypic analysis supported slower splitting of aggregates and a nonsignificant trend for larger group sizes in chimeras. The transcriptomic comparison and phenotypic analyses support discoordination among aggregate group members due to social conflict. These results are consistent with previously observed factors that affect cell fate decision in <em>D. discoideum </em>and provide evidence for plasticity in cAMP signaling and phenotypic coordination during development in response to social conflict in <em>D. discoideum </em>and similar microbial social groups.</p>
Data from: Stalk size and altruism investment within and among populations of the social amoeba
Reproductive division of labor is common in many societies, including those of eusocial insects, cooperatively breeding vertebrates, and most forms of multicellularity. However, conflict over what is best for the individual versus the group can prevent an optimal division of labor from being achieved. In the social amoeba <i>Dictyostelium discoideum</i>, cells aggregate to become multicellular and a fraction behaves altruistically, forming a dead stalk that supports the rest. Theory suggests that intraorganismal conflict over spore-stalk cell fate can drive rapid evolutionary change in allocation traits, leading to polymorphisms within populations or rapid divergence between them. Here we assess several proxies for stalk size and spore-stalk allocation as metrics of altruism investment among strains and across geographic regions. We observe geographic divergence in stalk height that can be partly explained by differences in multicellular size, as well as variation among strains in clonal spore-stalk allocation, suggesting within-population variation in altruism investment. Analyses of chimeras comprised of strains from the same versus different populations indicated genotype-by-genotype epistasis, where the morphology of the chimeras deviated significantly from the average morphology of the strains developed clonally. The significantly negative epistasis observed for allopatric pairings suggests that populations are diverging in their spore-stalk allocation behaviors, generating incompatibilities when they encounter one another. Our results demonstrate divergence in microbial social traits across geographically separated populations and demonstrate how quantification of genotype-by-genotype interactions can elucidate the trajectory of social trait evolution in nature.
Facultative symbiont virulence determines horizontal transmission rate without host specificity in Dictyostelium discoideum social amoebas
<p>In facultative symbioses, only a fraction of hosts are associated with symbionts. Specific host and symbiont pairings may be the result of host-symbiont coevolution driven by reciprocal selection, or priority effects pertaining to which potential symbiont became associated with a host first. Distinguishing between these possibilities is important for understanding the evolutionary forces that affect facultative symbioses. We used the social amoeba <em>Dictyostelium discoideum</em> and its symbiont <em>Paraburkholderia bonniea </em>to determine whether ongoing coevolution affects which host-symbiont strain pairs naturally co-occur within a facultative symbiosis. Relative to other <em>Paraburkholderia</em>,<em> </em>including another symbiont of <em>D. discoideum</em>, <em>P. bonniea</em> features a reduced genome size that indicates a significant history of coevolution with its host. We hypothesized that ongoing host-symbiont coevolution would lead to higher fitness for naturally co-occurring (native) host and symbiont pairings compared to novel pairings. We show for the first time that <em>P. bonniea</em> symbionts can horizontally transmit to new amoeba hosts when hosts aggregate together during the social stage of their life cycle. Here we find evidence for a virulence-transmission trade-off without host specificity. Although symbiont strains were significantly variable in virulence and horizontal transmission rate, hosts and symbionts responded similarly to associations in native and novel pairings. We go on to identify candidate virulence factors in the genomes of <em>P. bonniea </em>strains that may contribute to variation in virulence. We conclude that ongoing coevolution is unlikely for <em>D. discoideum </em>and <em>P. bonniea. </em>The system instead appears to represent a stable facultative symbiosis in which naturally co-occurring <em>P. bonniea </em>host and symbiont pairings are the result of priority effects.</p>
Data from: In the social amoeba Dictyostelium discoideum, shortened stalks may limit obligate cheater success even when exploitable partners are available
<p>Cooperation is widespread across life, but its existence can be threatened by exploitation. The rise of obligate social cheaters that are incapable of contributing to a necessary cooperative function can lead to the loss of that function. In the social amoeba <em>Dictyostelium discoideum</em>, obligate social cheaters cannot form dead stalk cells and in chimeras instead form living spore cells. This gives them a competitive advantage within chimeras. However, obligate cheaters of this kind have thusfar not been found in nature, probably because they are often enough in clonal populations that they need to retain the ability to produce stalks. In this study we discovered an additional cost to obligate cheaters. Even when there are wild-type cells to parasitize, the chimeric fruiting bodies that result have shorter stalks and these are disadvantaged in spore dispersal. The inability of obligate cheaters to form fruiting bodies when they are on their own combined with the lower functionality of fruiting bodies when they are not represent limits on obligate social cheating as a strategy<em>.</em></p>
Data from: Stalk size and altruism investment within and among populations of the social amoeba
Open the record for dataset details and reuse information.
Data from: In the social amoeba Dictyostelium discoideum, shortened stalks may limit obligate cheater success even when exploitable partners are available
Open the record for dataset details and reuse information.
Facultative symbiont virulence determines horizontal transmission rate without host specificity in Dictyostelium discoideum social amoebas
Open the record for dataset details and reuse information.
Wild Dictyostelium discoideum social amoebae show plastic responses to the presence of nonrelatives during multicellular development
Open the record for dataset details and reuse information.
Data from: Genetic signatures of microbial altruism and cheating in social amoebas in the wild
Many microbes engage in social interactions. Some of these have come to play an important role in the study of cooperation and conflict, largely because, unlike most animals, they can be genetically manipulated and experimentally evolved. However, whereas animal social behavior can be observed and assessed in natural environments, microbes usually cannot, so we know little about microbial social adaptations in nature. This has led to some difficult-to-resolve controversies about social adaptation even for well-studied traits such as bacterial quorum sensing, siderophore production, and biofilms. Here we use molecular signatures of population genetics and molecular evolution to address controversies over the existence of altruism and cheating in social amoebas. First, we find signatures of rapid adaptive molecular evolution that are consistent with social conflict being a significant force in nature. Second, we find population-genetic signatures of purifying selection to support the hypothesis that the cells that form the sterile stalk evolve primarily through altruistic kin selection rather than through selfish direct reproduction. Our results show how molecular signatures can provide insight into social adaptations that cannot be observed in their natural context, and they support the hypotheses that social amoebas in the wild are both altruists and cheaters.
Data from: Genetic signatures of microbial altruism and cheating in social amoebas in the wild
Open the record for dataset details and reuse information.
Data from: Sentinel cells, symbiotic bacteria, and toxin resistance in the social amoeba Dictyostelium discoideum
The social amoeba Dictyostelium discoideum is unusual among eukaryotes in having both unicellular and multicellular stages. In the multicellular stage, some cells, called sentinels, ingest toxins, waste, and bacteria. The sentinel cells ultimately fall away from the back of the migrating slug, thus removing these substances from the slug. However, some D. discoideum clones called farmers carry commensal bacteria through the multicellular stage while others called non-farmers do not. Farmers profit from their beneficial bacteria. To prevent the loss of these bacteria, we hypothesize that sentinel cell numbers may be reduced in farmers and thus farmers may have a diminished capacity to respond to pathogenic bacteria or toxins. In support, we found that farmers have fewer sentinel cells compared to non-farmers. However, farmers produced no fewer viable spores when challenged with a toxin. These results are consistent with the beneficial bacteria, Burkholderia, providing protection against toxins. The farmers did not vary in spore production with and without a toxin challenge the way the non-farmers did, which suggests the costs of Burkholderia may be fixed while sentinel cells may be inducible. Therefore, the costs for non-farmers are only paid in the presence of the toxin. When the farmers were cured of their symbiotic bacteria with antibiotics, they behaved just like non-farmers in response to a toxin challenge. Thus, the advantages farmers gain from carrying bacteria include not just food and protection against competitors, but also protection against toxins.
Data from: Sex ratio and gamete size across eastern North America in Dictyostelium discoideum, a social amoeba with three sexes
Theory indicates that numbers of mating types should tend towards infinity or remain at two. The social amoeba, Dictyostelium discoideum, however, has three mating types. It is therefore a mystery how this species has broken the threshold of two mating types, but has not increased towards a much higher number. Frequency dependent selection on rare types in combination with isogamy, a form of reproduction involving gametes similar in size, could explain the evolution of multiple mating types in this system. Other factors, such as drift, may be preventing the evolution of more than three. We first looked for evidence of isogamy by measuring gamete size associated with each type. We found no evidence of size dissimilarities between gametes. We then looked for evidence of balancing selection, by examining mating type distributions in natural populations and comparing genetic differentiation at the mating type locus to that at more neutral loci. We found that mating type frequency varied among the three populations we examined, with only one of the three showing an even sex ratio, which does not support balancing selection. However, we found more population structure at neutral loci than the mating type locus, suggesting that the three mating types are indeed maintained at intermediate frequencies by balancing selection. Overall, the data are consistent with balancing selection acting on D. discoideum mating types, but with a sufficiently weak rare sex advantage to allow for drift, a potential explanation for why these amoebae have only three mating types.
Data from: Fruiting bodies of the social amoeba Dictyostelium discoideum increase spore transport by Drosophila
Background: Many microbial phenotypes are the product of cooperative interactions among cells, but their putative fitness benefits are often not well understood. In the cellular slime mold Dictyostelium discoideum, unicellular amoebae aggregate when starved and form multicellular fruiting bodies in which stress-resistant spores are held aloft by dead stalk cells. Fruiting bodies are thought to be adaptations for dispersing spores to new feeding sites, but this has not been directly tested. Here we experimentally test whether fruiting bodies increase the rate at which spores are acquired by passing invertebrates. Results: Drosophila melanogaster accumulate spores on their surfaces more quickly when exposed to intact fruiting bodies than when exposed to fruiting bodies physically disrupted to dislodge spore masses from stalks. Flies also ingest and excrete spores that still express a red fluorescent protein marker. Conclusions: Multicellular fruiting bodies created by D. discoideum increase the likelihood that invertebrates acquire spores that can then be transported to new feeding sites. These results thus support the long-hypothesized dispersal benefits of altruism in a model system for microbial cooperation.
Data from: The rate and effects of spontaneous mutation on fitness traits in the social amoeba, Dictyostelium discoideum
We performed a mutation accumulation (MA) experiment using the social amoeba Dictyostelium discoideum to estimate the rate and distribution of effects of spontaneous mutations affecting eight putative fitness traits. We found that the per generation mutation rate for most fitness components is 0.0019 mutations per haploid genome per generation, or larger. This rate is an order of magnitude higher than estimates for fitness components in the unicellular eukaryote Saccharomyces cerevisiae, even though the base-pair substitution rate is two orders of magnitude lower. The high rate of fitness-altering mutations observed in this species may be partially explained by a large mutational target relative to Saccharomyces cerevisiae. Also, fitness-altering mutations may occur primarily at simple sequence repeats, which are common throughout the genome, including in coding regions, and may represent a target that is particularly likely to give fitness effects upon mutation. The majority of mutations had deleterious effects on fitness, but there was evidence for a substantial fraction, up to 40%, being beneficial for some of the putative fitness traits. Competitive ability within the multicellular slug appears to be under weak directional selection, perhaps reflecting the fact that slugs are sometimes, but not often, comprised of multiple clones in nature. Evidence for pleiotropy among fitness components across MA lines was absent, suggesting that mutations tend to act on single fitness components.
Data from: Sentinel cells, symbiotic bacteria, and toxin resistance in the social amoeba Dictyostelium discoideum
Open the record for dataset details and reuse information.
Data from: The rate and effects of spontaneous mutation on fitness traits in the social amoeba, Dictyostelium discoideum
Open the record for dataset details and reuse information.
Data from: Sex ratio and gamete size across eastern North America in Dictyostelium discoideum, a social amoeba with three sexes
Open the record for dataset details and reuse information.
Data from: Fruiting bodies of the social amoeba Dictyostelium discoideum increase spore transport by Drosophila
Open the record for dataset details and reuse information.
Data from: The specificity of Burkholderia symbionts in the social amoeba farming symbiosis: prevalence, species, genetic and phenotypic diversity
Open the record for dataset details and reuse information.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.