An Interaction Network of RNA-Binding Proteins Involved in Drosophila Oogenesis

DuringDrosophilaoogenesis, the localization and translational regulation of maternal transcripts relies on RNA-binding proteins (RBPs). Many of these RBPs localize several mRNAs and may have additional direct interaction partners to regulate their functions. Using immunoprecipitation from wholeDrosophilaovaries coupled to mass spectrometry, we examined protein-protein associations of 6 GFP-tagged RBPs expressed at physiological levels. Analysis of the interaction network and further validation in human cells allowed us to identify 26 previously unknown associations, besides recovering several well characterized interactions. We identified interactions between RBPs and several splicing factors, providing links between nuclear and cytoplasmic events of mRNA regulation. Additionally, components of the translational and RNA decay machineries were selectively co-purified with some baits, suggesting a mechanism for how RBPs may regulate maternal transcripts. Given the evolutionary conservation of the studied RBPs, the interaction network presented here provides the foundation for future functional and structural studies of mRNA localization across metazoans. The interaction network of six RBPs involved inDrosophilaoogenesis has been determined using both label-free and dimethyl labeling MS-based proteomics. These RBPs have overlapping functions inDrosophiladevelopment. The results reported 26 novel associations validatedin vitro, including interactions with splicing factors and translational regulators, suggesting a mechanism for how RBPs may regulate maternal transcripts during oogenesis. Given the evolutionary conservation of the selected RBPs, the study provides the foundation for future functional and structural studies across systems.