RT Journal Article
SR Electronic
T1 Single-molecule imaging reveals distinct effects of ligands on CCR5 dynamics depending on its dimerization status
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.12.20.473455
DO 10.1101/2021.12.20.473455
A1 Fanny Momboisse
A1 Giacomo Nardi
A1 Philippe Colin
A1 Melany Hery
A1 Nelia Cordeiro
A1 Olivier Schwartz
A1 Nathalie Sauvonnet
A1 Fernando Arenzana-Seisdedos
A1 Thibault Lagache
A1 Bernard Lagane
A1 Jean-Christophe Olivo-Marin
A1 Anne Brelot
YR 2021
UL http://biorxiv.org/content/early/2021/12/20/2021.12.20.473455.abstract
AB G protein-coupled receptors (GPCR) are present at the cell surface in different conformational and oligomeric states. However, how these states impact GPCRs biological function and therapeutic targeting remains incompletely known. Here, we investigated this issue in living cells for the CC chemokine receptor 5 (CCR5), a major receptor in inflammation and the principal entry co-receptor for Human Immunodeficiency Viruses (HIV-1). We used TIRF microscopy and an original statistical method to track and classify the motion of different receptors subpopulations. We showed a diversity of ligand-free forms of CCR5 at the cell surface constituted of various oligomeric states and exhibiting transient Brownian and restricted motions. These forms were stabilized differently by distinct ligands. In particular, agonist stimulation restricted the mobility of CCR5 and led to its clustering, a feature depending on β-arrestin, while inverse agonist stimulation exhibited the opposite effect. These results suggest a link between receptor activation and immobilization. Applied to HIV-1 envelope glycoproteins gp120, our quantitative analysis revealed agonist-like properties of gp120s. Distinct gp120s influenced CCR5 dynamics differently, suggesting that they stabilize different CCR5 conformations. Then, using a dimerization-compromized mutant, we showed that dimerization (i) impacts CCR5 precoupling to G proteins, (ii) is a pre-requisite for the immobilization and clustering of receptors upon activation, and (iii) regulates receptor endocytosis, thereby impacting the fate of activated receptors. This study demonstrates that tracking the dynamic behavior of a GPCR is an efficient way to link GPCR conformations to their functions, therefore improving the development of drugs targeting specific receptor conformations.Competing Interest StatementThe authors have declared no competing interest.