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The crystal structure of mouse VDAC1 at 2.3 A resolution reveals mechanistic insights into metabolite gating.

ABSTRACT: The voltage-dependent anion channel (VDAC) constitutes the major pathway for the entry and exit of metabolites across the outer membrane of the mitochondria and can serve as a scaffold for molecules that modulate the organelle. We report the crystal structure of a beta-barrel eukaryotic membrane protein, the murine VDAC1 (mVDAC1) at 2.3 A resolution, revealing a high-resolution image of its architecture formed by 19 beta-strands. Unlike the recent NMR structure of human VDAC1, the position of the voltage-sensing N-terminal segment is clearly resolved. The alpha-helix of the N-terminal segment is oriented against the interior wall, causing a partial narrowing at the center of the pore. This segment is ideally positioned to regulate the conductance of ions and metabolites passing through the VDAC pore.

SUBMITTER: Ujwal R

PROVIDER: S-EPMC2584669 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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The crystal structure of mouse VDAC1 at 2.3 A resolution reveals mechanistic insights into metabolite gating.

Ujwal Rachna R Cascio Duilio D Colletier Jacques-Philippe JP Faham Salem S Zhang Jun J Toro Ligia L Ping Peipei P Abramson Jeff J

Proceedings of the National Academy of Sciences of the United States of America 20081106 46

The voltage-dependent anion channel (VDAC) constitutes the major pathway for the entry and exit of metabolites across the outer membrane of the mitochondria and can serve as a scaffold for molecules that modulate the organelle. We report the crystal structure of a beta-barrel eukaryotic membrane protein, the murine VDAC1 (mVDAC1) at 2.3 A resolution, revealing a high-resolution image of its architecture formed by 19 beta-strands. Unlike the recent NMR structure of human VDAC1, the position of th ...[more]

PMID: 18988731

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