Summary
Cellular signaling by membrane G protein-coupled receptors (GPCRs) is orchestrated by a complex and diverse array of mechanisms. The dynamics of a GPCR interactome as it evolves over time and space in response to an agonist can offer a unique window on pleiotropic signaling decoding and functional selectivity at a cellular level. In this study, we employed proximity-based APEX2 proteomics to interrogate the interaction network of the GPCR for luteinizing hormone (LHR) on a sub-minute timescale. We developed an analytical approach integrating quantitative multiplexed proteomics and temporal reference profiles, providing a platform to identify the proteomic environment of APEX2-tagged LHR at the nanometer scale. LHR activity is exquisitely regulated at a spatial level, leading to identification of novel interactors including the Ras-related GTPase RAP2B that modulate both receptor signaling and post-endocytic trafficking, and providing a resource for spatiotemporal nanodomain mapping of LHR interactors across subcellular compartments.
Competing Interest Statement
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. EWT is a founder, shareholder, and director of Myricx Pharma Ltd. The remaining authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article.
