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From membrane tension to channel gating: A principal energy transfer mechanism for mechanosensitive channels.

ABSTRACT: Mechanosensitive (MS) channels are evolutionarily conserved membrane proteins that play essential roles in multiple cellular processes, including sensing mechanical forces and regulating osmotic pressure. Bacterial MscL and MscS are two prototypes of MS channels. Numerous structural studies, in combination with biochemical and cellular data, provide valuable insights into the mechanism of energy transfer from membrane tension to gating of the channel. We discuss these data in a unified two-state model of thermodynamics. In addition, we propose a lipid diffusion-mediated mechanism to explain the adaptation phenomenon of MscS.

SUBMITTER: Zhang XC

PROVIDER: S-EPMC5079242 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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From membrane tension to channel gating: A principal energy transfer mechanism for mechanosensitive channels.

Zhang Xuejun C XC Liu Zhenfeng Z Li Jie J

Protein science : a publication of the Protein Society 20160823 11

Mechanosensitive (MS) channels are evolutionarily conserved membrane proteins that play essential roles in multiple cellular processes, including sensing mechanical forces and regulating osmotic pressure. Bacterial MscL and MscS are two prototypes of MS channels. Numerous structural studies, in combination with biochemical and cellular data, provide valuable insights into the mechanism of energy transfer from membrane tension to gating of the channel. We discuss these data in a unified two-state ...[more]

PMID: 27530280

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