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

• DOI: 10.1073/pnas.0609996104
• Publication Date: 2007-03-28T03:41:55Z
• Authors: Yoshitaka Nakayama; Kenta Fujiu; Masahiro Sokabe; Kenjiro Yoshimura
• Keywords: Chlamydomonas; Chlamydomonas reinhardtii

MscS is a mechanosensitive channel that ubiquitous among bacteria. Recent progress in the genome projects has revealed homologs of are also present eukaryotes, but whether they operate as ion channels unknown. In this study we cloned MSC1, homolog Chlamydomonas, and examined its function when expressed Escherichia coli. Full-length MSC1 was not functional E. coli cells. However, removal N-terminal signal sequence (DeltaN-MSC1) reversed effect. DeltaN-MSC1 found to open response membrane stretch displayed preference for anions over cations permeable ions. exhibited marked hysteretic behavior ascending descending stimuli. That is, gating occurred significant stimuli remained until stimulus almost completely removed. Indirect immunofluorescence punctate spots cytoplasm chloroplasts. Moreover, knockdown expression resulted abnormal localization chlorophyll. These findings show an intracellular responsible organization chloroplast Chlamydomonas.