Sex-specific regulation of meiosis (#19)
Meiosis is the specialized cell division in which a single DNA replication event is followed by two successive rounds of chromosome segregation to produce haploid gametes for sexual reproduction. Errors in meiosis can cause aneuploidy, a major cause of both miscarriage and genetic developmental disorders in humans. The meiotic program is regulated in a sex-specific manner to generate the unique gamete types of sperm and egg. During meiotic prophase, crossing over between homologous chromosomes serves to ensure proper segregation and promote genetic variation in both males and females, yet the recombination landscape is distinct between the sexes. Additionally, in many organisms, including humans and C. elegans, chromosome segregation during female meiosis is acentriolar and highly asymmetric, while in males, segregation is centriolar and symmetric. Using the simple metazoan C. elegans, we have identified molecular components that are critical for meiotic recombination, chromosome segregation and checkpoint signaling, but which have different functions in male versus female meiosis. Taking advantage of genome editing tools and live cell imaging in the worm, our data suggest that distinct mechanisms mediate chromosome behavior in the sexes.