title: Genetics of esterases in Drosophila. IV. Slow-migrating S-esterase in Drosophila of the virilis group.
abstract: A slow-migrating beta-esterase (S-esterase) is described which has been detected in Drosophila montana, Drosophila imeretensis, and some stocks of Drosophila virilis when mixtures of alpha- and beta-naphthyl acetate are used as substrates in histochemical reactions after electrophoresis. Sexual dimorphism for S-esterase has been demonstrated. This esterase is contained in male genitalia only, predominantly in the ejaculatory bulb (waxy plug). It appears 3-4 days after emergence of flies. In hybrids between S+ and So species, the activity of the slow esterase is either decreased or inhibited. An autonomous synthesis of the S- esterase in the ejaculatory bulb was established by transplantation of imaginal genital discs into larvae of different Drosophila stocks. Based on analysis of physiochemical and immunochemical properties, S-esterase is suggested to be an independent fraction of esterase, possibly dimeric, which does not cross-react with beta-esterase antiserum.
mesh_terms: D000818:Animals; D003433:Crosses, Genetic; D004330:Drosophila / Q000201:enzymology*; D004950:Esterases / Q000032:analysis / Q000302:isolation & purification; D014644:Genetic Variation; D005837:Genitalia, Male / Q000201:enzymology*; D006824:Hybridization, Genetic; D005779:Immunodiffusion; D007814:Larva; D008297:Male; D009154:Mutation; D010641:Phenotype; D013045:Species Specificity
chemical_list: D004950:Esterases