16 October 2009
Centre for Organelle Research
University of Stavanger, Norway, and
Dartmouth Medical School, Hanover, NH
In this talk I will present approaches how to describe homeostatic mechanisms, discussing the concept of robustness, how the concept of 'integral feedback/integral control' can be reflected by kinetic conditions and how oscillations can arise in certain 'robust' homeostatic controllers. Starting point will be a brief description of the balancing approach [1-3] to describe temperature homeostasis of the period or fluxes for oscillatory or nonoscillatory networks, respectively. Then I will turn to robust perfect adaptation, how robust perfect adaptation sites may be identified , how integral control/integral feedback can be related to zero-order fluxes, state the need for robust inflow or outflow homeostatic control mechanisms, and how robust homeostatic controllers lead to 'almost robust' temperature compensation . Under certain conditions harmonic oscillations are observed in an inflow homeostatic controller, and the suggestion is made that p53 oscillations may be the result of a homeostatic control mechanism becoming operative when p53 is upregulated.
current theory lunch schedule