Ectopic Expression Screen Reveals the Protective and Toxic Effects of Drosophila Seminal Fluid Proteins

• Published in: Genetics (Austin) 2007-02, Vol.175 (2), p.777-783
• Main Authors: Mueller, J.L, Page, J.L, Wolfner, M.F
• Format: Article
• Language: English
• Subjects: accessory sex glands; Animals; antibacterial properties; antimicrobial peptides; bacterial infections; Confidence intervals; Drosophila; Drosophila melanogaster; Drosophila melanogaster - drug effects; Drosophila melanogaster - microbiology; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Drosophila Proteins - pharmacology; Drosophila Proteins - toxicity; fecundity; Female; Females; Gene Expression; Gene Expression Regulation - drug effects; immune response; insect proteins; Insects; Investigations; Male; Oviposition - drug effects; Proteins; seminal plasma; Seminal Plasma Proteins - genetics; Seminal Plasma Proteins - metabolism; Seminal Plasma Proteins - pharmacology; Seminal Plasma Proteins - toxicity; Serratia Infections; Serratia marcescens; Serratia marcescens - drug effects; Serratia marcescens - growth & development; Sexual Abstinence - drug effects; Sexual Behavior, Animal - drug effects
• ISSN: 0016-6731; 1943-2631; 1943-2631
• DOI: 10.1534/genetics.106.065318

In Drosophila melanogaster, seminal fluid regulates the reproductive and immune responses of mated females. Some seminal fluid proteins may provide protective functions to mated females, such as antimicrobial activity and/or stimulation of antimicrobial gene expression levels, while others appear to have negative effects, contributing to a "cost of mating." To identify seminal proteins that could participate in these phenomena, we used a systemic ectopic expression screen to test the effects on unmated females of proteins normally produced by the male accessory gland (Acps). Of the 21 ectopically expressed Acps that we tested for ability to assist in the clearance of a bacterial infection with Serratia marcescens, 3 Acps significantly reduced the bacterial counts of infected females, suggesting a protective role. Of the 23 Acps that we tested for toxicity, 3 were toxic, including one that has been implicated in the cost of mating in another study. We also tested ectopic expression females for other Acp-induced effects, but found no additional Acps that affected egg laying or receptivity upon ectopic expression.