title: Dexras1: shaping the responsiveness of the circadian clock.
abstract: Living organisms are endowed with an autonomous timekeeping program that not only maintains circadian rhythms of behaviour and physiology but is reset by cues from the external, cyclic environment. Intracellular signaling events that mediate entrainment of the mammalian circadian clock by photic (light) as well as non-photic inputs are only beginning to be elucidated. Dexras1 is a novel Ras-like G protein that modulates multiple signaling cascades. Genetic ablation of Dexras1 in mice (dexras1(-/-)) results in altered responsiveness of the master circadian clock to photic and non-photic cues. This review will attempt to provide mechanistic insights into the involvement of Dexras1 in biological timing processes based on its role as a modulator of signal transduction.
authors.affiliation: Department of Medical Biophysics, The University Health Network, University of Toronto, 610 University Avenue, Toronto, Ont., Canada M5G 2M9. hymcheng@yahoo.ca
authors.forename: Hai-Ying Mary
authors.initials: HY
authors.lastname: Cheng
authors.forename: Karl
authors.initials: K
authors.lastname: Obrietan
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000235:genetics* / Q000528:radiation effects; D002940:Circadian Rhythm / Q000235:genetics* / Q000528:radiation effects; D019204:GTP-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005786:Gene Expression Regulation; D008027:Light; D051379:Mice; D018345:Mice, Knockout; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics / Q000502:physiology*
chemical_list: D020928:Mitogen-Activated Protein Kinases; D019204:GTP-Binding Proteins; D018631:ras Proteins