tailieunhanh - Báo cáo khoa học: Osmosensing and signaling in the regulation of mammalian cell function

Volume changes of mammalian cells as induced by either anisoosmolarity or under isoosmotic conditions by hormones, substrates and oxidative stress critically contribute to the regulation of metabolism, gene expression and the susceptibility to stress. | ỊFEBS Journal MINIREVIEW Osmosensing and signaling in the regulation of mammalian cell function Freimut Schliess Roland Reinehr and Dieter Haussinger Clinic for Gastroenterology Hepatology and Infectiology Heinrich-Heine-University Dusseldorf Germany Keywords apoptosis bile acids CD95 cell volume epidermal growth factor insulin integrins osmolytes oxidative stress proliferation Correspondence F. Schliess Heinrich-Heine-Universitat Universitatsklinikum Klinik fur Gastroenterologie und Infektiologie Moorenstrasse 5 D-40225 Dusseldorf Germany Fax 49 211 81 17517 Tel 49 211 81 18941 E-mail schliess@ Received 2 July 2007 accepted 29 August 2007 doi Volume changes of mammalian cells as induced by either anisoosmolarity or under isoosmotic conditions by hormones substrates and oxidative stress critically contribute to the regulation of metabolism gene expression and the susceptibility to stress. Osmosensing . the registration of cell volume triggers signal transduction pathways towards effector sites osmosignaling which link alterations of cell volume to a functional outcome. This minireview summarizes recent progress in the understanding of how osmosensing and osmosignaling integrate into the overall context of growth factor signaling and the execution of apoptotic programs. Introduction Sudden exposure of cells to hypo- or hyperosmotic solutions induces a rapid osmotic swelling or shrinkage respectively. Extensive swelling or shrinkage is counteracted by induction of a regulatory volume decrease RVD or increase respectively 1-3 . Most hypoosmotically swollen cells perform RVD by a release of inorganic ions including K Na Cl- and HCO3- and organic osmolytes . taurine betaine . Hyperosmotic regulatory volume increase RVI at a short-term time scale is performed by activation of electrolyte uptake . via Na K 2Cl cotransport and Na H exchange . Long-term adaption to hyperosmolarity includes an isoosmotic .