Structural and functional studies of CC chemokine receptor 5 phosphorylation and its interactions with arrestin2

ABSTRACT: The two non-visual arrestin isoforms, arrestin2 and arrestin3, recognize and bind hundreds of G protein-coupled receptors (GPCRs) with different phosphorylation patterns leading to distinct functional outcomes. Whereas the impact of phosphorylation of the vasopressin 2 receptor and rhodopsin on arrestin interactions has been well studied, much less known for other GPCRs. Here we have characterized the interaction between the phosphorylated CC chemokine receptor 5 (CCR5) and arrestin2. Mass spectrometry and biochemical revealed several new CCR5 phosphorylation sites, which proved essential for the formation of stable complexes with arrestin2. Crystal structures of arrestin2 in apo form and in complexes with two CCR5 C-terminal phosphopeptides revealed three key CCR5 phosphoresidues in a pXpp motif that form extensive interactions with arrestin2 and lead to activation. The same phosphoresidue-cluster is present in other receptors which form stable complexes with arrestin2. The contributions of each CCR5 phosphoresidue on arrestin2 conformation and binding have been characterized by a combination of NMR spectroscopy, biochemical and functional assays. We propose that the identified pXpp motif is responsible for robust arrestin2 recruitment in many GPCRs. Moreover, an analysis of available sequence, structural and functional information on other GPCR arrestin interactions suggests a particular spatial arrangement of phosphoresidues within the GPCR intracellular loops and C-terminal tail determines arrestin2 and 3 isoform specificity.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Cell Culture

SUBMITTER: Alexander Schmidt  

LAB HEAD: Alex Schmidt

PROVIDER: PXD036220 | Pride | 2023-05-24

REPOSITORIES: Pride