Cryo–electron microscopy structure of the antidiuretic hormone arginine-vasopressin V2 receptor signaling complex

Abstract

The antidiuretic hormone arginine-vasopressin (AVP) forms a signaling complex with the V2 receptor (V2R) and the Gs protein, promoting kidney water reabsorption. Molecular mechanisms underlying activation of this critical G protein–coupled receptor (GPCR) signaling system are still unknown. To fill this gap of knowledge, we report here the cryo–electron microscopy structure of the AVP-V2R-Gs complex. Single-particle analysis revealed the presence of three different states. The two best maps were combined with computational and nuclear magnetic resonance spectroscopy constraints to reconstruct two structures of the ternary complex. These structures differ in AVP and Gs binding modes. They reveal an original receptor-Gs interface in which the Gαs subunit penetrates deep into the active V2R. The structures help to explain how V2R R137H or R137L/C variants can lead to two severe genetic diseases. Our study provides important structural insights into the function of this clinically relevant GPCR signaling complex.

Structure of the vasopressin hormone-V2 receptor-β-arrestin1 ternary complex

“…4A ). We speculate that G69 and H70 residues of the V2R ICL1, which have been shown to interact with the N-ter helix of Gs α subunit ( 22 ), are probably involved in this interaction. Second, although ICL2 is not entirely seen in the density map, this V2R region (residues R139 to A147) strikingly binds in a particularly well-defined furrow between the N-and C-lobes of βarr1ΔCT, lying in a central position ( Fig.…”

“…Here, we describe the cryo-electron microscopy (cryo-EM) structure of the AVP-bound wild-type human V2R in complex with a truncated form of human βarr1 stabilized by the single-chain variable fragment of Fab30 (ScFv30). Together with the recent structures of the active conformation of the AVP-bound V2R in complex with the Gs protein ( 22–24 ), these new findings provide major molecular and structural information to better understand arrestin-GPCR interactions as well as V2R­associated signaling pathways.…”

“…This interaction has also been seen in the M2R-βarr1 and the β1AR-βarr1 complexes ( 20, 21 ), strengthening this hypothesis. Interestingly, R137 3.50 is part of the ionic lock motif (broken in the active V2R conformation) and has been shown to directly interact with the free carboxylic acid function of the Gs protein α subunit Cter in the active structure of the AVP-V2R-Gs-Nb35 complex ( 22 ).…”

“…We recently determined the structure of the AVP-bound V2R-Gs complex ( 22 ), which led us to compare it with the AVP-bound V2R-βarr1 complex ( Fig. 6A ).…”

Functional Rescue of a Nephrogenic Diabetes Insipidus Causing Mutation in the V2 Vasopressin Receptor by Specific Antagonist and Agonist Pharmacochaperones

“…Despite the lack of robust effect of tolvaptan pretreatment on receptor translocation from intracellular compartments to plasma membrane, Figure 3A demonstrates that tolvaptan pretreatment effectively rescued the cAMP generation capability of the S127F-V2R mutant in response to AVP (Figure 3A). The third transmembrane helix of the V2R (including the residue 127) is involved in the AVP binding (Slusarz et al, 2006a;Slusarz et al, 2006b), but the S127 is not in direct contact with AVP based on the 3D structure of AVP-V2R complex (Bous et al, 2021). Taken together, the impaired response to AVP stimulation is rather due to intracellular-endoplasmic reticulum retention but it cannot be excluded that both plasma membrane expression and AVP affinity may be modified by the S127F mutation.…”