LAUSR

Cohesins play an important role in organizing the meiotic chromosome structure, but how cohesins themselves are regulated during this process is not entirely clear. Taking advantage of conditional depletion, point mutations and quantitative immunofluorescence, this study finds that the kinase CHK‐2 is a master regulator of cohesin stabilization during meiosis in Caenorhabditis elegans. Surprisingly, CHK‐2, a known downstream effector of ATM‐1 in DNA damage response, promotes ATM‐1 activity in the worm germline. Curiously, consensus CHK‐2 phosphorylation sites are found in ATM orthologues from several organisms suggesting this may be a conserved mechanism. The findings will be of broad interest to chromosome biologists and developmental biologists.