Structure of the receptor-activated human TRPC6 and TRPC3 ion channels.

ABSTRACT: TRPC6 and TRPC3 are receptor-activated nonselective cation channels that belong to the family of canonical transient receptor potential (TRPC) channels. They are activated by diacylglycerol, a lipid second messenger. TRPC6 and TRPC3 are involved in many physiological processes and implicated in human genetic diseases. Here we present the structure of human TRPC6 homotetramer in complex with a newly identified high-affinity inhibitor BTDM solved by single-particle cryo-electron microscopy to 3.8?Å resolution. We also present the structure of human TRPC3 at 4.4?Å resolution. These structures show two-layer architectures in which the bell-shaped cytosolic layer holds the transmembrane layer. Extensive inter-subunit interactions of cytosolic domains, including the N-terminal ankyrin repeats and the C-terminal coiled-coil, contribute to the tetramer assembly. The high-affinity inhibitor BTDM wedges between the S5-S6 pore domain and voltage sensor-like domain to inhibit channel opening. Our structures uncover the molecular architecture of TRPC channels and provide a structural basis for understanding the mechanism of these channels.

SUBMITTER: Tang Q 

PROVIDER: S-EPMC6028632 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature