mating response genes

Male-derived accessory gland proteins (Acps) that are transferred to females during mating have profound effects on female reproductive physiology including increased ovulation, mating inhibition, and effects on sperm utilization and storage. The extreme rates of evolution seen in Acps may be driven by sperm competition and sexual conflict, processes which may ultimately drive complex interactions between female- and male-derived molecules and sperm. However, little is known of how gene expression in female reproductive tissues changes in response to the presence of male molecules and sperm. To characterize this response, we conducted parallel genomic and proteomic analyses of gene expression in the reproductive tract of 3-day-old unmated and mated female Drosophila melanogaster. Using DNA microarrays, we identified 539 transcripts that are differentially expressed in unmated vs. mated females and revealed a striking peak in differential expression at 6 hrs postmating and a marked shift from primarily down-regulated to primarily up-regulated transcripts within 3 hrs after mating. Combining two-dimensional gel electrophoresis and liquid chromatography mass spectrometry analyses, we identified 84 differentially expressed proteins at 3 hrs postmating, including proteins which appeared to undergo post-translational modification. Together, our observations define transcriptional and translational response to mating within the female reproductive tract and suggest a bimodal model of postmating gene expression initially correlated with mating and the final stages of female reproductive tract maturation and later with the declining presence of male reproductive molecules and with sperm maintenance and utilization. Keywords: keywords: reproduction, reproductive tract, accessory gland proteins, sperm, timecourse Three-day-old mated and unmated females were dissected to remove the lower reproductive tract (upper uterus, sperm-storage organs, and accessory glands). Mated females were dissected either immediately following mating (0 hr) or at 3, 6, or 24 hrs following the termination of mating. Tracts of 12-40 females of like category were pooled and total RNA extracted via a TRIzol-based protocol. Processing and labeling of transcript was performed by the Molecular Biology Core Facility at the Medical College of Georgia. Arrays from mated females at the different timepoints were compared to unmated females.