Abstract

Water excretion by the kidney is regulated by the neurohypophyseal peptide hormone vasopressin through actions in renal collecting duct cells to regulate the water channel protein, aquaporin-2. Vasopressin signalling is initiated by binding to a G-protein coupled receptor V2R, which signals through Gsα, adenylyl cyclase 6, and activation of the cAMP-regulated protein kinase (PKA). Signaling events coupling PKA activation and aquaporin-2 were largely unknown until the advent of modern protein mass spectrometry techniques that allow proteome-wide quantification of protein phosphorylation changes (phosphoproteomics). This short review documents phosphoproteomic findings in collecting duct cells describing the response to V2-selective vasopressin agonists and antagonists, the response to CRISPR-mediated deletion of PKA, results from in vitro phosphorylation studies using recombinant PKA, the response to the broad spectrum kinase inhibitor H89, and the responses underlying lithium-induced nephrogenic diabetes insipidus. These phosphoproteomic datasets have been made available online for modelling vasopressin signalling and signalling downstream from other Gsα-coupled receptors.