Caenorhabditis elegans Chk2-like gene is essential for meiosis but dispensable for DNA repair

A Chk2-like gene was identified in the genome of Caenorhabditis elegans. Th e putative gene product, termed Ce-chk-2 consists of 450 amino acid residue s, and shows good homology with the Chk2/Cds1 gene family. The results of R NA-mediated interference (RNAi) indicated that the F1 generation from dsRNA injected animals grew to adulthood, but approximately 95% of their eggs (F 2) died during early embryogenesis, Among the few surviving progeny, males (XO animals) arose at an abnormally high frequency (30%). In addition, 12 u nivalents were observed in full grown oocytes of the F1, while six bivalent s were normally observed in mild-type oocytes, Ce-chk-2 gene expression inc reased in the adult stage, and their expression level decreased in the glp- 4 mutant, which is defective in germ line proliferation. The radiation sens itivity of F1 embryos carrying Ce-chk-2 RNAi was not significantly affected . (C) 2000 Federation of European Biochemical Societies. Published by Elsev ier Science B.V. All rights reserved.