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Crystal structure of a voltage-gated K+ channel pore module in a closed state in lipid membranes.

ABSTRACT: Voltage-gated K(+) channels underlie the electrical excitability of cells. Each subunit of the functional tetramer consists of the tandem fusion of two modules, an N-terminal voltage-sensor and a C-terminal pore. To investigate how sensor coupling to the pore generates voltage-dependent channel opening, we solved the crystal structure and characterized the function of a voltage-gated K(+) channel pore in a lipid membrane. The structure of a functional channel in a membrane environment at 3.1 Å resolution establishes an unprecedented connection between channel structure and function. The structure is unique in delineating an ion-occupied ready to conduct selectivity filter, a confined aqueous cavity, and a closed activation gate, embodying a dynamic entity trapped in an unstable closed state.

SUBMITTER: Santos JS

PROVIDER: S-EPMC3522301 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Crystal structure of a voltage-gated K+ channel pore module in a closed state in lipid membranes.

Santos Jose S JS Asmar-Rovira Guillermo A GA Han Gye Won GW Liu Wei W Syeda Ruhma R Cherezov Vadim V Baker Kent A KA Stevens Raymond C RC Montal Mauricio M

The Journal of biological chemistry 20121024 51

Voltage-gated K(+) channels underlie the electrical excitability of cells. Each subunit of the functional tetramer consists of the tandem fusion of two modules, an N-terminal voltage-sensor and a C-terminal pore. To investigate how sensor coupling to the pore generates voltage-dependent channel opening, we solved the crystal structure and characterized the function of a voltage-gated K(+) channel pore in a lipid membrane. The structure of a functional channel in a membrane environment at 3.1 Å r ...[more]

PMID: 23095758

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