NEW GENES FOR MALE ACCESSORY-GLAND PROTEINS IN DROSOPHILA-MELANOGASTER

The accessory gland of male insects produces components of the seminal fluid that alter the behavior, physiology and life span of the mated female, and contribute to her efficient storage and utilization of spe rm. As a step towards understanding how this occurs, we have isolated genes encoding 12 previously unreported accessory gland-specific mRNAs from the fruit fly Drosophila melanogaster. We report here the restri ction maps of the new genes, the chromosome positions - which are all autosomal - of the 11 non-repetitive genes, their expression patterns, and the sequences of the accessory gland proteins (Acps) encoded by n ine of the genes. Eight of the proteins predicted from these sequences begin with putative secretion signals. Following their signal sequenc es, three of the predicted molecules are peptides and the other five a re larger polypeptides with characteristics of cleavable prohormones. The ninth molecule, which has an N-terminal hydrophobic region but no consensus signal peptide cleavage site, is predicted to be a 716 amino acid glycoprotein. Of the nine proteins, two have intriguing similari ties to sequences in protein databases. Acp76A is a 388 amino acid pro -protein which contains a signature sequence for the serpin class of p rotease inhibitors. The 115 amino acid Acp62F has a 28 amino acid regi on of high sequence similarity to a neurotoxin of the Brazilian armed spider Phoneutria nigriventer. Models are discussed in which Acp76A pl ays a role in the observed regulation of Acp proteolysis and/or in the coagulation of seminal fluid to form a mating plug, and in which Acp6 2F contributes to the reported toxicity of Drosophila seminal fluid. ( C) 1997 Elsevier Science Ltd. All rights reserved.