Disease relevance of mscL

• A large-conductance mechanosensitive channel in E. coli encoded by mscL alone [1].
• We found a gene homologous to mscL in Clostridium perfringens which is located just downstream from the collagenase-encoding gene in the opposite direction [2].
• We introduced an mscL gene into Vibrio alginolyticus, and the mechanosensitive channel with large conductance functions was found to alleviate cell lysis by osmotic downshock [3].

High impact information on mscL

• Insertional disruption of mscL removes the channel activity, whereas re-expression of mscL borne on an expression plasmid restores it [1].
• The mscL nucleotide sequence predicts a unique protein of only 136 amino acids, with a highly hydrophobic core and very different from porins or other known proteins [1].
• One gene, mscL, encoding a large conductance channel has previously been described, but null mutants were without well-defined phenotypes [4].
• Using chromatographies to enrich the target and patch clamp to assay the channel activity in liposome-reconstituted fractions, we identified the MscL protein and cloned the mscL gene [5].
• Reduced levels of MS proteins and reduced expression of mscL- and mscS-LacZ fusions in an rpoS mutant strain suggested that the RNA polymerase holoenzyme containing sigmaS is responsible, at least in part, for regulating production of MS channel proteins [6].

References