Cytoplasmic components of the machinery mediating telomere-led rapid chromosome movements in mouse meiosis

Telomere-led rapid chromosome movements (RPMs) are a prominent characteristic of chromosome dynamics during meiosis. Although of crucial importance in maintaining germ cell integrity, the extranuclear portion of the machinery supporting RPMs in mammals is poorly understood. Using an unbiased proteomic approach to identify motor proteins associated to microtubules in mouse meiotic cells, complemented with co-immunoprecipitation confirmation, we uncovered kinesins as candidate of the machinery mediating RPMs in mouse spermatocytes. Further biochemical, microscopy, and functional analysis shows that KIF5B and KIF2B interact with KASH5 and act as motor proteins mediating the LINC complex-microtubule interactions. Our results show that member of the kinesin family of molecular motors act as novel critical modules of the machinery promoting complex dynamic chromosomes in mammals.