GSE168878
Sequencing of RNA and footprints of wildtype and RpS5b mutant Drosophila ovaries [RIBO-seq]
Emerging evidence suggests that ribosome heterogeneity may have important functional consequences in the translation of specific mRNAs within different cell types and under various conditions. Ribosome heterogeneity comes in many forms including post-translational modification of ribosome proteins (RPs), lack of specific RPs, and different RP paralogs incorporation. The Drosophila genome encodes for two RPS5 paralogs, RpS5a and RpS5b. While RpS5a is expressed ubiquitously, RpS5b exhibits enriched expression in the reproductive system. Deletion of RpS5b results in female sterility marked by developmental arrest of egg chambers at stages 7-8 and posterior follicle cell (PFC) hyperplasia. Both phenotypes are caused by defects in the germline and over-expression of RpS5a can compensate it. RpS5b mutant display increased rRNA transcription and RP production, accompanied by increased protein synthesis. Loss of RpS5b leads to microtubule-based defects and mislocalization of several factors, leading failure of Notch pathway activation in PFCs. Together, our results indicate that germ cell specific expression of RpS5b promotes proper egg chamber development by regulating both ribosome homeostasis and protein trafficking during mid-oogenesis. Overall design: RNA-seq and footprint-seq experiment to compare gene expression as well as ribosome distribution between wildtype and the mutant ovaries.