Development of an antibody fragment that stabilizes GPCR/G-protein complexes

• DOI: 10.1038/s41467-018-06002-w
• Publication Date: 2018-09-07T09:26:38Z
• Authors: Shoji Maeda; Antoine Koehl; Hugues Matile; Hongli Hu; Daniel Hilger; Gebhard F. X. Sch...; Aashish Manglik; Georgios Skiniotis; Roger J. P. Dawson; Brian K. Kobilka
• Keywords: Cryo-Electron Microscopy

Abstract Single-particle cryo-electron microscopy (cryo-EM) has recently enabled high-resolution structure determination of numerous biological macromolecular complexes. Despite this progress, the application cryo-EM to G protein coupled receptors (GPCRs) in complex with heterotrimeric proteins remains challenging, owning both relative small size and limited stability these assemblies. Here we describe development antibody fragments that bind stabilize GPCR-G complexes for cryo-EM. One particular, mAb16, stabilizes GPCR/G-protein by recognizing an interface between Gα Gβγ subunits heterotrimer, confers resistance GTPγS-triggered dissociation. The unique recognition mode makes it possible transfer its binding stabilizing effect other G-protein subtypes through minimal engineering. This fragment is thus a broadly applicable tool structural studies