title: Characterization of the role of a mechanosensitive channel in osmotic down shock adaptation in Synechocystis sp PCC 6803.
abstract: Synechocystis sp strain PCC 6803 contains one gene encoding a putative large conductance mechanosensitive channel homolog [named SyMscL (slr0875)]. However, it is unclear whether SyMscL contributes to the adaptation to hypoosmotic stress in Synechocystis. Here we report the in vivo characteristics of SyMscL. SyMscL was mainly expressed in the plasma membrane of Synechocystis. Cell volume monitoring using stopped-flow spectrophotometry showed that ΔsymscL cells swelled more rapidly than wild-type cells under hypoosmotic stress conditions. Expression of symscL was under circadian control, and its peak corresponded to the beginning of subjective night. These results indicate that SyMscL functioned as one component of the osmotic homeostatic regulatory system of the cell coordinating the response of Synechocystis to daily metabolic osmotic fluctuations and environmental changes.
authors.affiliation: Department of Biomolecular Engineering; Graduate School of Engineering; Tohoku University; Sendai, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Nanatani
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shijuku
authors.forename: Masaro
authors.initials: M
authors.lastname: Akai
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Yukutake
authors.forename: Masato
authors.initials: M
authors.lastname: Yasui
authors.forename: Shin
authors.initials: S
authors.lastname: Hamamoto
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Onai
authors.forename: Megumi
authors.initials: M
authors.lastname: Morishita
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ishiura
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Uozumi
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002940:Circadian Rhythm; D004777:Environment; D042541:Intracellular Space / Q000378:metabolism; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism*; D009997:Osmotic Pressure; D021381:Protein Transport; D046939:Synechocystis / Q000166:cytology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D007473:Ion Channels
keywords: Synechocystis; circadian rhythm; hypoosmotic stress adaptation; mechanosensitive channel