The bacterial mechanosensitive channels MscS and MscL have been shown to protect cells from hypo-osmotic shock-induced lysis. Bacterial strains deficient for MscS and MscL are severely compromised and fail to survive a hypo-osmotic shock. Both channels exhibit redundant function such that re-introduction of either of these proteins is sufficient to restore cell survival. Several proteins paralogous to MscS have been identified in E. coli, but their function remains unknown. Mechanosensitive channel homologues are also being discovered in a variety of organisms including Archaea, plants and fungi and their function is starting to emerge.