Computational molecular analysis of human rhodopsin, transducin and arrestin interactions: An insight into signal transduction for ophthalmology

Abstract

Retinal G-protein receptor; rhodopsin upon light-activation, gets phosphorylated, experiences conformational shift and interacts with G-protein; transducin. To completely obstruct the signal transduction visual protein; arrestin binds consecutively to disrupt the cationic channels of plasma membrane. Experimented binding assays documents the protein interactions but hitherto computational investigation was undone. This probe aims at the computational study of conformational alterations in rhodopsin upon sequential interactions, accompanied by variations in its surface electrostatic potential and net solvent accessible area. 3D structures of human transducin, arrestin and rhodopsin were analyzed. Residual participation from the optimized and simulated trio-complex (rhodopsintransducin-arrestin) disclosed that predominantly positively charged amino-acid residues; Arg474, Arg412, Arg229, Arg13, Lys15 and Lys408 from rhodopsin participated with transducin and arrestin forming 9 ionic interactions. Rhodopsin was perceived to interact in a gradual firmer pattern with its partner proteins. This study presents a novel viewpoint into the computational disclosure for participation of concerned visual proteins.