wtf: Killing gametes for more than 110 million years
Killer meiotic drivers are parasitic genes that promote their own transmission into the progeny by actively destroying gametes that do not inherit the driver allele from a heterozygote (driver+/driver-). Meiotic drivers are predicted to play a significant role in shaping genome evolution. The newly discovered wtf genes of Schizosaccharomyces pombe are a family of meiotic driver genes that encode two proteins: a poison that kills gametes and an antidote that protects only the gametes that inherit the driver. Meiotic drivers are predicted to have a very short lifespan because do not persist for long evolutionary periods. Here we show that the meiotic driver wtf is present in Schizosaccharomyces lineage for more than 110 million years.
Currently, wtf genes are reported to be found only within S. pombe. We recently identified 63 wtf genes in S. octosporus and 5 in S. cryophilus. We have shown that S. octosporus wtf genes share features with S. pombe wtf genes. They share a high number of exons, two predicted translational start sites and are associated to repetitive elements. We show that S. octosporus wtf genes can encode both poison and antidote proteins that allows to favorize their own transmission in the population. S. octosporus and S. pombe have diverge 110 million years ago. The finding of wtf genes in S. octosporus and S. cryophilus mean that wtf genes are born more than 110 million years ago. wtf family is the oldest active meiotic driver identified.