John Gagnon

A maternal-effect selfish genetic element in Caenorhabditis elegans
Ben-David E, Burga A, Kruglyak L.
Science. 2017 Jun 9;356(6342):1051-1055. doi: 10.1126/science.aan0621. Epub 2017 May 11.
Department of Human Genetics, Department of Biological Chemistry, and Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095, USA. [email protected] [email protected] [email protected]
Selfish genetic elements spread in natural populations and have an important role in genome evolution. We discovered a selfish element causing embryonic lethality in crosses between wild strains of the nematode Caenorhabditis elegans The element is made up of sup-35, a maternal-effect toxin that kills developing embryos, and pha-1, its zygotically expressed antidote. pha-1 has long been considered essential for pharynx development on the basis of its mutant phenotype, but this phenotype arises from a loss of suppression of sup-35 toxicity. Inactive copies of the sup-35/pha-1 element show high sequence divergence from active copies, and phylogenetic reconstruction suggests that they represent ancestral stages in the evolution of the element. Our results suggest that other essential genes identified by genetic screens may turn out to be components of selfish elements.
June 21, 2017
HSW 1057 at noon