7S60

Human KATP channel in open conformation, focused on Kir and one SUR, position 4

Summary for 7S60

• Entry DOI: 10.2210/pdb7s60/pdb
• Related: 7S5T 7S5V 7S5X 7S5Y 7S5Z
• EMDB information: 24845
• Descriptor: ATP-sensitive inward rectifier potassium channel 11, ATP-binding cassette sub-family C member 8, ADENOSINE-5'-DIPHOSPHATE, ... (5 entities in total)
• Functional Keywords: ion channel, katp, atp-sensitive potassium channel, membrane protein
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 5
• Total formula weight: 352711.24

Authors

Zhao, C.,MacKinnon, R. (deposition date: 2021-09-12, release date: 2021-12-01, Last modification date: 2024-11-13)

Primary citation

Zhao, C.,MacKinnon, R.
Molecular structure of an open human K ATP channel.
Proc.Natl.Acad.Sci.USA, 118:-, 2021

PubMed Abstract: K channels are metabolic sensors that translate intracellular ATP/ADP balance into membrane excitability. The molecular composition of K includes an inward-rectifier potassium channel (Kir) and an ABC transporter-like sulfonylurea receptor (SUR). Although structures of K have been determined in many conformations, in all cases, the pore in Kir is closed. Here, we describe human pancreatic K (hK) structures with an open pore at 3.1- to 4.0-Å resolution using single-particle cryo-electron microscopy (cryo-EM). Pore opening is associated with coordinated structural changes within the ATP-binding site and the channel gate in Kir. Conformational changes in SUR are also observed, resulting in an area reduction of contact surfaces between SUR and Kir. We also observe that pancreatic hK exhibits the unique (among inward-rectifier channels) property of PIP-independent opening, which appears to be correlated with a docked cytoplasmic domain in the absence of PIP.

PubMed: 34815345
DOI: 10.1073/pnas.2112267118

Experimental method

ELECTRON MICROSCOPY (3.7 Å)