Molecular and electrophysiological characterization of a mechanosensitive channel expressed in the chloroplasts of Chlamydomonas.

ABSTRACT: MscS is a mechanosensitive channel that is ubiquitous among bacteria. Recent progress in the genome projects has revealed that homologs of MscS are also present in eukaryotes, but whether they operate as ion channels is unknown. In this study we cloned MSC1, a homolog of MscS in Chlamydomonas, and examined its function when expressed in Escherichia coli. Full-length MSC1 was not functional when expressed in E. coli cells. However, removal of the N-terminal signal sequence (DeltaN-MSC1) reversed this effect. DeltaN-MSC1 was found to open in response to membrane stretch and displayed a preference for anions over cations as permeable ions. DeltaN-MSC1 exhibited marked hysteretic behavior in response to ascending and descending stimuli. That is, channel gating occurred in response to significa

SUBMITTER: Nakayama Y 

PROVIDER: S-EPMC1851586 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature