Download MendeleyCryo-EM structure of human rhodopsin bound to an inhibitory G protein.
Kang, Y., Kuybeda, O., de Waal, P.W., Mukherjee, S., Van Eps, N., Dutka, P., Zhou, X.E., Bartesaghi, A., Erramilli, S., Morizumi, T., Gu, X., Yin, Y., Liu, P., Jiang, Y., Meng, X., Zhao, G., Melcher, K., Ernst, O.P., Kossiakoff, A.A., Subramaniam, S., Xu, H.E.(2018) Nature 558: 553-558
- PubMed: 29899450
- DOI: https://doi.org/10.1038/s41586-018-0215-y
- Primary Citation of Related Structures:
6CMO - PubMed Abstract:
G-protein-coupled receptors comprise the largest family of mammalian transmembrane receptors. They mediate numerous cellular pathways by coupling with downstream signalling transducers, including the hetrotrimeric G proteins G s (stimulatory) and G i (inhibitory) and several arrestin proteins. The structural mechanisms that define how G-protein-coupled receptors selectively couple to a specific type of G protein or arrestin remain unknown. Here, using cryo-electron microscopy, we show that the major interactions between activated rhodopsin and G i are mediated by the C-terminal helix of the G i α-subunit, which is wedged into the cytoplasmic cavity of the transmembrane helix bundle and directly contacts the amino terminus of helix 8 of rhodopsin. Structural comparisons of inactive, G i -bound and arrestin-bound forms of rhodopsin with inactive and G s -bound forms of the β 2 -adrenergic receptor provide a foundation to understand the unique structural signatures that are associated with the recognition of G s , G i and arrestin by activated G-protein-coupled receptors.
Organizational Affiliation:
Center for Cancer and Cell Biology, Innovation and Integration Program, Van Andel Research Institute, Grand Rapids, MI, USA.
