Structural highlights
Function
GNAI1_HUMAN Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems. The G(i) proteins are involved in hormonal regulation of adenylate cyclase: they inhibit the cyclase in response to beta-adrenergic stimuli. The inactive GDP-bound form prevents the association of RGS14 with centrosomes and is required for the translocation of RGS14 from the cytoplasm to the plasma membrane. May play a role in cell division.[1] [2]
Publication Abstract from PubMed
Single-particle cryo-electron microscopy (cryo-EM) has recently enabled high-resolution structure determination of numerous biological macromolecular complexes. Despite this progress, the application of high-resolution cryo-EM to G protein coupled receptors (GPCRs) in complex with heterotrimeric G proteins remains challenging, owning to both the relative small size and the limited stability of these assemblies. Here we describe the development of antibody fragments that bind and stabilize GPCR-G protein complexes for the application of high-resolution cryo-EM. One antibody in particular, mAb16, stabilizes GPCR/G-protein complexes by recognizing an interface between Galpha and Gbetagamma subunits in the heterotrimer, and confers resistance to GTPgammaS-triggered dissociation. The unique recognition mode of this antibody makes it possible to transfer its binding and stabilizing effect to other G-protein subtypes through minimal protein engineering. This antibody fragment is thus a broadly applicable tool for structural studies of GPCR/G-protein complexes.
Development of an antibody fragment that stabilizes GPCR/G-protein complexes.,Maeda S, Koehl A, Matile H, Hu H, Hilger D, Schertler GFX, Manglik A, Skiniotis G, Dawson RJP, Kobilka BK Nat Commun. 2018 Sep 13;9(1):3712. doi: 10.1038/s41467-018-06002-w. PMID:30213947[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Cho H, Kehrl JH. Localization of Gi alpha proteins in the centrosomes and at the midbody: implication for their role in cell division. J Cell Biol. 2007 Jul 16;178(2):245-55. PMID:17635935 doi:10.1083/jcb.200604114
- ↑ Johnston CA, Siderovski DP. Structural basis for nucleotide exchange on G alpha i subunits and receptor coupling specificity. Proc Natl Acad Sci U S A. 2007 Feb 6;104(6):2001-6. Epub 2007 Jan 30. PMID:17264214
- ↑ Maeda S, Koehl A, Matile H, Hu H, Hilger D, Schertler GFX, Manglik A, Skiniotis G, Dawson RJP, Kobilka BK. Development of an antibody fragment that stabilizes GPCR/G-protein complexes. Nat Commun. 2018 Sep 13;9(1):3712. doi: 10.1038/s41467-018-06002-w. PMID:30213947 doi:http://dx.doi.org/10.1038/s41467-018-06002-w
