IBN#9506927 Wakimoto The overall aim of this proposal is to identify products of paternal origin that are required for early embryogenesis in Drosophila melangaster. This proposal concentrates on three genes, the sneaky, paternal loss and ms(3)K81 genes. Mutations of these genes act as paternal effect mutations that cause defects in development within minutes after entry of the sperm into the egg. These mutations will be used to identify the molecules required for normal response of the sperm to the egg cytoplasm, for syngamy and for stable maintenance of the paternal chromosomes in the zygote. The RNA and protein products of these genes will be identified and their subcellular distribution during spermatogenesis and embryogenesis will be determined. To study the function of these products, the consequences of mutations that alter the level or distribution of the snky, pal and K81 products will be analyzed. Mutant transgenes designed to test the function of specific domains of the RNA or protein products will be constructed in vitro and introduced into flies by germ line transformation. New snky mutations will be isolated and genetically characterized. These studies should contribute to a more comprehensive understanding of the differences between the paternal and maternal contributions and the regulation of the events that ensure their successful union during the earliest stages of embryogenesis. ***
