Yang Fan, Yu Xiao, Liu Chuan, Qu Chang-Xiu, Gong Zheng, Liu Hong-Da, Li Fa-Hui, Wang Hong-Mei, He Dong-Fang, Yi Fan, Song Chen, Tian Chang-Lin, Xiao Kun-Hong, Wang Jiang-Yun, Sun Jin-Peng
Laboratory of Quantum Biophysics and Laboratory of RNA Biology, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, 100101, China.
Key Laboratory Experimental Teratology of the Ministry of Education and Department of Biochemistry and Molecular Biology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012, China.
Nat Commun. 2015 Sep 8;6:8202. doi: 10.1038/ncomms9202.
Specific arrestin conformations are coupled to distinct downstream effectors, which underlie the functions of many G-protein-coupled receptors (GPCRs). Here, using unnatural amino acid incorporation and fluorine-19 nuclear magnetic resonance ((19)F-NMR) spectroscopy, we demonstrate that distinct receptor phospho-barcodes are translated to specific β-arrestin-1 conformations and direct selective signalling. With its phosphate-binding concave surface, β-arrestin-1 'reads' the message in the receptor phospho-C-tails and distinct phospho-interaction patterns are revealed by (19)F-NMR. Whereas all functional phosphopeptides interact with a common phosphate binding site and induce the movements of finger and middle loops, different phospho-interaction patterns induce distinct structural states of β-arrestin-1 that are coupled to distinct arrestin functions. Only clathrin recognizes and stabilizes GRK2-specific β-arrestin-1 conformations. The identified receptor-phospho-selective mechanism for arrestin conformation and the spacing of the multiple phosphate-binding sites in the arrestin enable arrestin to recognize plethora phosphorylation states of numerous GPCRs, contributing to the functional diversity of receptors.
特定的抑制蛋白构象与不同的下游效应器相偶联,这是许多G蛋白偶联受体(GPCR)功能的基础。在此,我们利用非天然氨基酸掺入和氟-19核磁共振((19)F-NMR)光谱法证明,不同的受体磷酸条形码被转化为特定的β-抑制蛋白-1构象并指导选择性信号传导。β-抑制蛋白-1通过其磷酸盐结合凹面“读取”受体磷酸化C末端的信息,并且(19)F-NMR揭示了不同的磷酸相互作用模式。虽然所有功能性磷酸肽都与一个共同的磷酸盐结合位点相互作用并诱导指状环和中环的运动,但不同的磷酸相互作用模式会诱导β-抑制蛋白-1的不同结构状态,这些状态与不同的抑制蛋白功能相偶联。只有网格蛋白能够识别并稳定GRK2特异性β-抑制蛋白-1构象。所确定的抑制蛋白构象的受体磷酸选择性机制以及抑制蛋白中多个磷酸盐结合位点的间距,使抑制蛋白能够识别众多GPCR的大量磷酸化状态,这有助于受体的功能多样性。