RT Journal Article
SR Electronic
T1 Evolutionary association of receptor-wide amino acids with G protein–coupling selectivity in aminergic GPCRs
JF Life Science Alliance
JO Life Sci. Alliance
FD Life Science Alliance LLC
SP e202201439
DO 10.26508/lsa.202201439
VO 5
IS 10
A1 Selçuk, Berkay
A1 Erol, Ismail
A1 Durdağı, Serdar
A1 Adebali, Ogün
YR 2022
UL http://www.life-science-alliance.org/content/5/10/e202201439.abstract
AB G protein-coupled receptors (GPCRs) induce signal transduction pathways through coupling to four main subtypes of G proteins (Gs, Gi, Gq, and G12/13), selectively. However, G protein selective activation mechanisms and residual determinants in GPCRs have remained obscure. Herein, we performed extensive phylogenetic analysis and identified specifically conserved residues for the aminergic receptors having similar coupling profiles. By integrating our methodology of differential evolutionary conservation of G protein–specific amino acids with structural analyses, we identified specific activation networks for Gs, Gi1, Go, and Gq. To validate that these networks could determine coupling selectivity we further analyzed Gs-specific activation network and its association with Gs selectivity. Through molecular dynamics simulations, we showed that previously uncharacterized Glycine at position 7x41 plays an important role in receptor activation and it may determine Gs coupling selectivity by facilitating a larger TM6 movement. Finally, we gathered our results into a comprehensive model of G protein selectivity called “sequential switches of activation” describing three main molecular switches controlling GPCR activation: ligand binding, G protein selective activation mechanisms, and G protein contact.