Selfing is the safest sex for Caenorhabditis tropicalis

PaperPlayer biorxiv evolutionary biology

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.07.242032v1?rss=1 Authors: Noble, L. M., Yuen, J., Stevens, L., Moya, N., Persaud, R. S., Moscatelli, M. A., Jackson, J. L., Braendle, C., Andersen, E. C., Seidel, H. S., Rockman, M. V. Abstract: Mating systems have profound effects on genetic diversity and compatibility. The convergent evolution of self-fertilization in three Caenorhabditis species provides a powerful lens to examine causes and consequences of mating system transitions. Among the selfers, C. tropicalis is the least genetically diverse and most afflicted by outbreeding depression. We generated a chromosomal-scale genome for C. tropicalis and surveyed global diversity. Population structure is very strong, and islands of extreme divergence punctuate a genomic background that is highly homogeneous around the globe. Outbreeding depression in the laboratory is caused largely by multiple gene drive elements, genetically consistent with maternal toxin/zygotic antidote systems. Driver loci harbor novel and duplicated genes, and their activity is modified by mito-nuclear background. Segregating drivers dramatically reduce fitness, and simulations show that selfing limits their spread. Frequent selfing in C. tropicalis may therefore be a strategy to avoid drive-mediated outbreeding depression. Copy rights belong to original authors. Visit the link for more info