title: Different conformational dynamics of various active states of β-arrestin1 analyzed by hydrogen/deuterium exchange mass spectrometry.
abstract: Arrestins have important roles in G protein-coupled receptor (GPCR) signaling including desensitization of GPCRs and G protein-independent signaling. Two major intra-molecular interactions, the polar core and the three-element region, maintain arrestins in the basal conformation by connecting the N- and C-domains. Mutations in these regions that disrupt the polar core (R169E or p44) or the three-element (3A) have been reported to interact with GPCRs in a phosphorylation-independent manner, and thus these mutants are referred to as pre-activated arrestins. On the other hand, deletion of 7 residues in the linker region between N- and C-domains (Δ7) freezes arrestins in the inactive state, which has a much lower binding affinity to GPCRs compared to the wild type form. Although these mutants are widely used for functional studies of arrestins, the conformations of these mutants have not yet been fully elucidated. Here, we analyzed the conformational dynamics of β-arrestin1 with various mutants (R169E, p44, 3A, and Δ7) by hydrogen/deuterium exchange mass spectrometry (HDX-MS). HDX-MS data revealed that pre-activated mutants have more deuterium uptake than the basal state, and also that the regions and degree of increased deuterium uptake differ between pre-activated mutants. Unexpectedly, the inactive mutant also showed increased deuterium uptake in a few regions.
authors: School of Pharmacy, Sungkyunkwan University, Suwon 440746, Republic of Korea.
authors: Dong Kyun
authors: DK
authors: Kim
authors: School of Pharmacy, Sungkyunkwan University, Suwon 440746, Republic of Korea.
authors: Youngjoo
authors: Y
authors: Yun
authors: School of Pharmacy, Sungkyunkwan University, Suwon 440746, Republic of Korea.
authors: Hee Ryung
authors: HR
authors: Kim
authors: College of Pharmacy & Department of Molecular Science and Technology, Ajou University, Suwon 443721, Republic of Korea.
authors: Min-Duk
authors: MD
authors: Seo
authors: School of Pharmacy, Sungkyunkwan University, Suwon 440746, Republic of Korea. Electronic address: kychung2@skku.edu.
authors: Ka Young
authors: KY
authors: Chung
mesh_terms: D000818:Animals; D019390:Arrestins / Q000737:chemistry* / Q000302:isolation & purification; D041961:Deuterium Exchange Measurement; D013058:Mass Spectrometry; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D011487:Protein Conformation; D051381:Rats; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; D000071557:beta-Arrestins
keywords: Conformational dynamics; Hydrogen/deuterium exchange mass spectrometry; Inactivation; Pre-activation; β-Arrestin