In species from nematodes to humans, many healthy, developing oocytes apoptose around the pachytene stage of meiosis. Why and how this happens is not known. Now, on , Boag and co-workers report that a conserved RNA-protein (RNP)complex regulates germline apoptosis in Caenorhabditis elegans. They identify a germline RNA-binding protein, CAR-1 (for cytokinesis/apoptosis/RNA binding), and show that it associates with the RNA helicase CGH-1 in an RNA-dependent manner within a germline RNP complex. This interaction is conserved in Drosophila oocytes. RNAi knockdown of CAR-1 in nematodes increases oocyte apoptosis, as does CGH-1 depletion. Unexpectedly, if apoptosis is prevented in worms with reduced car-1 expression,defects in oogenesis lead to gonad failure. The researchers conclude that CAR-1 has a conserved role in oogenesis and propose that germline apoptosis enhances the formation of functional oocytes.
