Circadian oscillations are found in many tissues and even in cultured cells. All clocks show a certain degree of self-sustainment – e.g. under tissue culture conditions – but in vivo are tightly controlled by the master circadian pacemaker of the suprachiasmatic nuclei (SCN). In the absence of external time cues, the SCN clock – and with it the whole organism – "free-runs" with a precise species-specific period of close to (but not exactly) 24 hours. This endogenous rhythm is determined by so called clock genes with circadian expression profiles, regulated via a system of interlocked transcriptional/translational feedback loops. These molecular oscillations are translated into physiological and, ultimately, behavioral rhythms by the circadian timing system. We are interested in the mechanistic basis of this translation process. How can the clock network integrate different timing signals from the environment, and how are clock gene rhythms translated into physiological functions?
Ongoing projects:
- Differentiating zeitgeber input to peripheral clock resetting.
- Mediators of peripheral metabolic feedback to CNS clock rhythms.
Selected References:
- Oxyntomodulin regulates resetting of the liver circadian clock by food. Landgraf D, Tsang AH, Leliavski A, Koch CE, Barclay JL, Drucker DJ, Oster H.Elife. 2015 Mar 30;4:e06253.
- The light-dark cycle controls peripheral rhythmicity in mice with a genetically ablated suprachiasmatic nucleus clock. Husse J, Leliavski A, Tsang AH, Oster H, Eichele G. FASEB J. 2014 Nov;28(11):4950-60.
- PKCgamma participates in food entrainment by regulating BMAL1. Zhang L, Abraham D, Lin ST, Oster H, Eichele G, Fu YH, Ptácek LJ. Proc Natl Acad Sci U S A. 2012 Dec 11;109(50):20679-84.
- Disturbed clockwork resetting in Sharp-1 and Sharp-2 single and double mutant mice. Rossner MJ, Oster H, Wichert SP, Reinecke L, Wehr MC, Reinecke J, Eichele G, Taneja R, Nave KA. PLoS One. 2008 Jul 23;3(7):e2762.
- Light entrainment of the mammalian circadian clock by a PRKCA-dependent posttranslational mechanism. Jakubcakova V, Oster H, Tamanini F, Cadenas C, Leitges M, van der Horst GT, Eichele G. Neuron. 2007 Jun 7;54(5):831-43.
