Membrane environment imposes unique selection pressures on transmembrane domains of G protein-coupled receptors.

ABSTRACT: We have investigated the influence of the plasma membrane environment on the molecular evolution of G protein-coupled receptors (GPCRs), the largest receptor family in Metazoa. In particular, we have analyzed the site-specific rate variation across the two primary structural partitions, transmembrane (TM) and extramembrane (EM), of these membrane proteins. We find that TM domains evolve more slowly than do EM domains, though TM domains display increased rate heterogeneity relative to their EM counterparts. Although the majority of residues across GPCRs experience strong to weak purifying selection, many GPCRs experience positive selection at both TM and EM residues, albeit with a slight bias towards the EM. Further, a subset of GPCRs, chemosensory receptors (including olfactory and taste r

SUBMITTER: Spielman SJ 

PROVIDER: S-EPMC3712645 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature