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Dynamic duo: Kir6 and SUR in K_ATP channel structure and function.

ABSTRACT: K_ATP channels are ligand-gated potassium channels that couple cellular energetics with membrane potential to regulate cell activity. Each channel is an eight subunit complex comprising four central pore-forming Kir6 inward rectifier potassium channel subunits surrounded by four regulatory subunits known as the sulfonylurea receptor, SUR, which confer homeostatic metabolic control of K_ATP gating. SUR is an ATP binding cassette (ABC) protein family homolog that lacks membrane transport activity but is essential for K_ATP expression and function. For more than four decades, understanding the structure-function relationship of Kir6 and SUR has remained a central objective of clinical significance. Here, we review progress in correlating the wealth of functional data in the literature with recent K_ATP cryoEM structures.

SUBMITTER: Patton BL

PROVIDER: S-EPMC10950283 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature

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Dynamic duo: Kir6 and SUR in KATP channel structure and function.

Patton Bruce L BL Zhu Phillip P ElSheikh Assmaa A Driggers Camden M CM Shyng Show-Ling SL

Channels (Austin, Tex.) 20240315 1

KATP channels are ligand-gated potassium channels that couple cellular energetics with membrane potential to regulate cell activity. Each channel is an eight subunit complex comprising four central pore-forming Kir6 inward rectifier potassium channel subunits surrounded by four regulatory subunits known as the sulfonylurea receptor, SUR, which confer homeostatic metabolic control of KATP gating. SUR is an ATP binding cassette (ABC) protein family homolog that lacks membrane ...[more]

PMID: 38489043

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