ジャーナル: Nat Struct Mol Biol / 年: 2022 タイトル: Structure determination of inactive-state GPCRs with a universal nanobody. 著者: Michael J Robertson / Makaía M Papasergi-Scott / Feng He / Alpay B Seven / Justin G Meyerowitz / Ouliana Panova / Maria Claudia Peroto / Tao Che / Georgios Skiniotis / 要旨: Cryogenic electron microscopy (cryo-EM) has widened the field of structure-based drug discovery by allowing for routine determination of membrane protein structures previously intractable. Despite ...Cryogenic electron microscopy (cryo-EM) has widened the field of structure-based drug discovery by allowing for routine determination of membrane protein structures previously intractable. Despite representing one of the largest classes of therapeutic targets, most inactive-state G protein-coupled receptors (GPCRs) have remained inaccessible for cryo-EM because their small size and membrane-embedded nature impedes projection alignment for high-resolution map reconstructions. Here we demonstrate that the same single-chain camelid antibody (nanobody) recognizing a grafted intracellular loop can be used to obtain cryo-EM structures of inactive-state GPCRs at resolutions comparable or better than those obtained by X-ray crystallography. Using this approach, we obtained structures of neurotensin 1 receptor bound to antagonist SR48692, μ-opioid receptor bound to alvimopan, apo somatostatin receptor 2 and histamine receptor 2 bound to famotidine. We expect this rapid, straightforward approach to facilitate the broad exploration of GPCR inactive states without the need for extensive engineering and crystallization.