Modeling feedback loops in the mammalian circadian oscillator [Elektronische Ressource] / von Sabine Becker-Weimann

Modeling Feedback Loops in the Mammalian CircadianOscillatorD I SS E R TAT I O Nzur Erlangung des akademischen Gradesdoctor rerum naturalium(Dr. rer. nat.)im Fach Biophysikeingereicht an derMathematisch-Naturwissenschaftlichen Fakultät IHumboldt-Universität zu BerlinvonFrau Dipl.-Biol. Sabine Becker-Weimanngeboren am 22.09.1976 in KarlsruhePräsident der Humboldt-Universität zu Berlin:Prof. Dr. Dr. h.c. Christoph MarkschiesDekan der Mathematisch-Naturwissenschaftlichen Fakultät I:Prof. Dr. Lutz-Helmut SchönGutachter:1. Prof. Dr. Hanspeter Herzel2. Prof. Dr. Achim Kramer3. Prof. Dr. Peter Ruoffeingereicht am: 4. September 2008Tag der mündlichen Prüfung: 7.Juli 2009iiAbstractIn many organisms the circadian clock ticks with a period of approximately 24hours and enables the organisms to keep track of time even without any environ-mental time cues. Numerous physiological and cellular processes underly circadianregulation. The molecular clock is a network of intracellular feedback loops: Theclock gene products directly or indirectly regulate their own transcription, whichresults in molecular oscillations.In this thesis, existing and new mathematical models of the circadian oscillator areused to investigate the meaning of structural features — in particular the design ofthe feedback loops — for fundamental circadian characteristics.