Your browser doesn't support javascript.
loading
A single phenylalanine residue in ß-arrestin2 critically regulates its binding to G protein-coupled receptors.
Jean-Charles, Pierre-Yves; Rajiv, Vishwaesh; Sarker, Subhodeep; Han, Sangoh; Bai, Yushi; Masoudi, Ali; Shenoy, Sudha K.
Afiliação
  • Jean-Charles PY; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Rajiv V; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Sarker S; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Han S; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Bai Y; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Masoudi A; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.
  • Shenoy SK; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA; Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA. Electronic address: skshenoy@dm.duke.edu.
J Biol Chem ; 298(5): 101837, 2022 05.
Article em En | MEDLINE | ID: mdl-35307348
ABSTRACT
Arrestins and their yeast homologs, arrestin-related trafficking adaptors (ARTs), share a stretch of 29 amino acids called the ART motif. However, the functionality of that motif is unknown. We now report that deleting this motif prevents agonist-induced ubiquitination of ß-arrestin2 (ß-arr2) and blocks its association with activated G protein-coupled receptors (GPCRs). Within the ART motif, we have identified a conserved phenylalanine residue, Phe116, that is critical for the formation of ß-arr2-GPCR complexes. ß-arr2 Phe116Ala mutant has negligible effect on blunting ß2-adrenergic receptor-induced cAMP generation unlike ß-arr2, which promotes rapid desensitization. Furthermore, available structures for inactive and inositol hexakisphosphate 6-activated forms of bovine ß-arr2 revealed that Phe116 is ensconced in a hydrophobic pocket, whereas the adjacent Phe117 and Phe118 residues are not. Mutagenesis of Phe117 and Phe118, but not Phe116, preserves GPCR interaction of ß-arr2. Surprisingly, Phe116 is dispensable for the association of ß-arr2 with its non-GPCR partners. ß-arr2 Phe116Ala mutant presents a significantly reduced protein half-life compared with ß-arr2 and undergoes constitutive Lys-48-linked polyubiquitination, which tags proteins for proteasomal degradation. We also found that Phe116 is critical for agonist-dependent ß-arr2 ubiquitination with Lys-63-polyubiquitin linkages that are known mediators of protein scaffolding and signal transduction. Finally, we have shown that ß-arr2 Phe116Ala interaction with activated ß2-adrenergic receptor can be rescued with an in-frame fusion of ubiquitin. Taken together, we conclude that Phe116 preserves structural stability of ß-arr2, regulates the formation of ß-arr2-GPCR complexes that inhibit G protein signaling, and promotes subsequent ubiquitin-dependent ß-arr2 localization and trafficking.
Assuntos
Palavras-chave

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Fenilalanina / Receptores Acoplados a Proteínas G / Beta-Arrestina 2 Tipo de estudo: Prognostic_studies Limite: Animals Idioma: En Revista: J Biol Chem Ano de publicação: 2022 Tipo de documento: Article País de afiliação: Estados Unidos

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Fenilalanina / Receptores Acoplados a Proteínas G / Beta-Arrestina 2 Tipo de estudo: Prognostic_studies Limite: Animals Idioma: En Revista: J Biol Chem Ano de publicação: 2022 Tipo de documento: Article País de afiliação: Estados Unidos