|Personal data||Research themes||Ongoing teaching||Publications|
Person in charge of the Unit : Oui
In the Unit of Theoretical Chronobiology, we investigate by means of theoretical models the molecular bases of biological rhythms and threshold phenomena at the cellular level. Our modeling approach primarily pertains to the oscillations and waves of cytosolic calcium, the circadian clock, the cell cycle, and cellular differentiation. We also focus on physiological implications of these processes and on their associated pathological disorders. In this context, we study the origin of calcium deregulations leading to infertility or Alzheimer's disease, as well as sleep phase disorders linked to dysfunction of the circadian clock, but also the influence of circadian rhythms on cell proliferation and cancer.
In response to a stimulation by a hormone or a neurotransmitter, most cells respond by repetitive increases of their intracellular calcium concentration. Moreover, each spike propagates as a wave both inside the cell and between adjacent cells. Using theoretical models developed in close collaboration with experimentalists, we study the mechanisms of these oscillations and waves, as well as their physiological roles. In particular, we develop coomputational tools allowing to investigate the role of calcium dynamics in physiological and pathophysiological porcesses such as secretion, fertilization or Alzheimer's disease.
In collaboration with the laboratory of Claire Chazaud (University of Clermont-Ferrand), we model the process of cellular differentiation of inner cells in epiblast and primitive endoderm, which occurs during early embryonic development in mice. In particular, we aim at understanding the role played by the FGF-MAPK signaling cascade. Another aspect of this research pertains to the molecular mechanism of the segmentation clock that controls somitogenesis.