OKRA AND SPINDLE-B ENCODE COMPONENTS OF THE RAD52 DNA-REPAIR PATHWAY AND AFFECT MEIOSIS AND PATTERNING IN DROSOPHILA OOGENESIS

okra (okr), spindle-B (spnB), and spindle-D (spnD) are three members o f a group of female sterile loci that produce defects in oocyte and eg g morphology, including variable dorsal-ventral defects in the eggshel l and embryo, anterior-posterior defects in the follicle cell epitheli um and in the oocyte, and abnormalities in oocyte nuclear morphology. Many of these phenotypes reflect defects in grk-Egfr signaling process es, and can be accounted for by a failure to accumulate wild-type leve ls of Gurken and Fs(1)K10. We have cloned okr and spnB, and show that okr encodes the Drosophila homolog of the yeast DNA-repair protein Rad 54, and spnB encodes a Rad51-like protein related to the meiosis-speci fic DMC1 gene. In functional tests of their role in DNA repair, we fin d that okr behaves like its yeast homolog in that it is required in bo th mitotic and meiotic cells. In contrast, spnB and spnD appear to be required only in meiosis. The fact that genes involved in meiotic DNA metabolism have specific effects on oocyte patterning implies that the progression of the meiotic cell cycle is coordinated with the regulat ion of certain developmental events during oogenesis.