@article {163323, title = {Bottleneck size drives the evolution of cooperative traits in an aggregative multicellular myxobacterium.}, journal = {PLoS Biol}, volume = {24}, year = {2026}, month = {2026 Jan}, pages = {e3003499}, abstract = {

Repeated population bottlenecks influence the evolution and maintenance of cooperation. However, it remains unclear whether bottlenecks select all cooperative traits expressed by an organism or only a subset of them. Myxococcus xanthus, a social bacterium, displays multiple cooperative traits, including growth, predation, sporulation in multicellular fruiting bodies, and germination. Using laboratory evolution experiments, we investigated the effect of repeated stringent versus relaxed population bottlenecks on the evolution of these four cooperative traits when they were all under selection. We found that only fruiting body formation and growth were positively selected under the stringent regimen, while the other two traits were selected against. The pattern was reversed in the relaxed regimen. Populations propagated under the relaxed regimen also exhibited greater fitness across the entire\ life cycle\ and maintained higher trait variations, including coexistence of cooperative and exploitative strategies. Genomic analyses identified mutations in σ54 interacting protein and DNA binding response regulator protein associated with adaptations in stringent and relaxed regimens, respectively. Furthermore, similar trade-offs, for example, between sporulation and germination, are also seen among natural populations of M. xanthus. Overall, we demonstrate that different bottleneck sizes drive the evolution of cooperative life history traits in distinct ways, often via trade-offs that constrain their joint optimization.

}, keywords = {Bacterial Proteins, Biological Evolution, Mutation, Myxococcus xanthus, Selection, Genetic, Spores, Bacterial}, issn = {1545-7885}, doi = {10.1371/journal.pbio.3003499}, url = {https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003499}, author = {Kalathera, Jyotsna and Jaiswal, Prakhar and Mandal, Neha and Patel, Vishwa and Guttal, Vishwesha and Krishna, Sandeep and Pande, Samay} } @article {159720, title = {Distinct filament morphology and membrane tethering features of the dual FtsZ paralogs in Odinarchaeota.}, journal = {EMBO J}, year = {2025}, month = {2025 Aug 08}, abstract = {

The Asgard phylum has emerged as a model to study eukaryogenesis because of their close relatedness with the eukaryotes. In this study, we use FtsZ proteins from a member of the class Odinarchaeia as representatives to investigate the probable origin, evolution, and assembly of the FtsZ/tubulin protein superfamily in Asgard archaea. We performed a comparative analysis of the biochemical properties and cytoskeletal assembly of FtsZ1 and FtsZ2, the two FtsZ isoforms in the Odinarchaeota metagenome. Our electron microscopy analysis reveals that OdinFtsZ1 assembles into curved single protofilaments, while OdinFtsZ2 forms stacked spiral ring-like structures. Upon sequence analysis, we identified an N-terminal amphipathic helix in OdinFtsZ1, which mediates direct membrane tethering. In contrast, OdinFtsZ2 is recruited to the membrane by the anchor OdinSepF via OdinFtsZ2{\textquoteright}s C-terminal tail. Overall, we report the presence of two distant evolutionary paralogs of FtsZ in Odinarchaeota, with distinct filament assemblies and differing modes of membrane targeting. Our findings highlight the diversity of FtsZ proteins in the archaeal phylum Asgardarchaeota, providing valuable insights into the evolution and differentiation of tubulin-family proteins.

}, issn = {1460-2075}, doi = {10.1038/s44318-025-00529-7}, author = {Kumari, Jayanti and Uthaman, Akhilesh and Bose, Sucharita and Kundu, Ananya and Sharma, Vaibhav and Dutta, Soumyajit and Dhar, Anubhav and Roy, Srijita and Srinivasan, Ramanujam and Pande, Samay and Vinothkumar, Kutti R and Gayathri, Pananghat and Palani, Saravanan} }