Structural highlights
FunctionABCC9_RAT Subunit of ATP-sensitive potassium channels (KATP). Can form cardiac and smooth muscle-type KATP channels with KCNJ11. KCNJ11 forms the channel pore while ABCC9 is required for activation and regulation. Publication Abstract from PubMedATP-sensitive potassium channels (K(ATP)), composed of Kir6 and SUR subunits, convert the metabolic status of the cell into electrical signals. Pharmacological activation of SUR2- containing K(ATP) channels by class of small molecule drugs known as K(ATP) openers leads to hyperpolarization of excitable cells and to vasodilation. Thus, K(ATP) openers could be used to treat cardiovascular diseases. However, where these vasodilators bind to K(ATP) and how they activate the channel remains elusive. Here, we present cryo-EM structures of SUR2A and SUR2B subunits in complex with Mg-nucleotides and P1075 or levcromakalim, two chemically distinct K(ATP) openers that are specific to SUR2. Both P1075 and levcromakalim bind to a common site in the transmembrane domain (TMD) of the SUR2 subunit, which is between TMD1 and TMD2 and is embraced by TM10, TM11, TM12, TM14, and TM17. These K(ATP) openers synergize with Mg-nucleotides to stabilize SUR2 in the NBD-dimerized occluded state to activate the channel. Structural identification of vasodilator binding sites on the SUR2 subunit.,Ding D, Wu JX, Duan X, Ma S, Lai L, Chen L Nat Commun. 2022 May 13;13(1):2675. doi: 10.1038/s41467-022-30428-y. PMID:35562524[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||
This page was last modified 10:21, 14 December 2022.