title: Circadian rhythm generation in a glioma cell line.
abstract: In mammals, the principal circadian oscillator resides in the hypothalamic suprachiasmatic nucleus. However, the basic components and the ability to generate a circadian rhythm are also characteristic of most peripheral tissues and some cell lines. In our present study, we show that the rat C6 glioma cell line displays circadian oscillations of reporter luciferase bioluminescence driven by the mouse Per2 promoter and of clock-related gene transcripts. Per2::luc expressing C6 cells display circadian rhythm in their bioluminescence levels for more than seven days. In addition, clock and clock-controlled genes show dynamic circadian oscillation in C6 cells after exposure to dexamethasone. It is also significant that Per1 is not induced in C6 cells by a calcium ionophore, which is in stark contrast to Rat-1 cells. The C6 glioma cell line has therefore the potential to be a useful tool in future investigations of the underlying molecular machinery of the circadian clock.
authors.affiliation: Department of Anatomy and Neurobiology, Kinki University School of Medicine, Osaka-Sayama, Osaka 589-8511, Japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Fujioka
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Takashima
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Shigeyoshi
mesh_terms: D000818:Animals; D019556:COS Cells; D018797:Cell Cycle Proteins; D045744:Cell Line, Tumor; D002522:Chlorocebus aethiops; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology*; D005576:Colforsin / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D005910:Glioma / Q000503:physiopathology*; D006736:Horses / Q000097:blood; D006801:Humans; D015759:Ionomycin / Q000494:pharmacology; D049449:Luminescence; D051379:Mice; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000502:physiology; D056950:Period Circadian Proteins; D011401:Promoter Regions, Genetic; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014157:Transcription Factors / Q000096:biosynthesis / Q000502:physiology; D015854:Up-Regulation
chemical_list: D018797:Cell Cycle Proteins; D009687:Nuclear Proteins; C539022:PER1 protein, human; C421902:PER2 protein, human; C512644:PER3 protein, human; C539023:Per1 protein, mouse; C539024:Per1 protein, rat; C513312:Per2 protein, mouse; C513311:Per2 protein, rat; C512645:Per3 protein, mouse; C512646:Per3 protein, rat; D056950:Period Circadian Proteins; D014157:Transcription Factors; D005576:Colforsin; D015759:Ionomycin; D003907:Dexamethasone; D013755:Tetradecanoylphorbol Acetate