Large-scale conformational rearrangement of the α5-helix of Gα subunits in complex with the guanine nucleotide exchange factor Ric8A.

ABSTRACT: Resistance to inhibitors of cholinesterase 8A (Ric8A) protein is an important G protein-coupled receptor (GPCR)-independent regulator of G protein α-subunits (Gα), acting as a guanine nucleotide exchange factor (GEF) and a chaperone. Insights into the complex between Ric8A and Gα hold the key to understanding the mechanisms underlying noncanonical activation of G-protein signaling as well as the folding of nascent Gα proteins. Here, we examined the structure of the complex of Ric8A with minimized Gα_i (miniGα_i) in solution by small-angle X-ray scattering (SAXS) and exploited the scattering profile in modeling of the Ric8A/miniGα_i complex by steered molecular dynamics (SMD) simulations. A small set of models of the complex featured minimal clash scores, excel

SUBMITTER: Srivastava D 

PROVIDER: S-EPMC6879328 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature