Proteomic differences between Drosophila melanogaster female reproductive tract tissue and fluid and their postmating responses

Fertility depends on the progression of complex and coordinated postmating processes within the extracellular luminal environment of the female reproductive tract (FRT). To achieve a more comprehensive level of knowledge regarding female-derived proteins available to interact with the ejaculate, we utilized semiquantitative mass spectrometry-based proteomics to study the composition of the FRT tissue and, separately, the luminal fluid, before and after mating in Drosophila melanogaster. Our approach leveraged whole-fly isotopic labelling to delineate between female proteins and those transferred from males in the ejaculate. The dynamic mating-induced proteomic changes in the extracellular FRT luminal fluid further informs our understanding of secretory mechanisms of the FRT and serves as a foundation for establishing the roles of ejaculate-female interactions in fertility.