The Leloup et al. (1999) Neurospora Model

 

This simple model consists of a single loop, containing only one gene, FREQUENCY, which negatively regulates itself. The rate of transcription is described by a Hill function, with the nuclear protein acting as a repressor. Messenger RNA is degraded in a Michaelis Menten manner, or is translated in a linear manner. Protein in the cytoplasm is degraded in a Michaelis Menten manner, or is transported into the nucleus, in a reversible first-order process, in order to provide negative feedback on the rate of transcription. The Hill coefficient describes the number of repressor molecules which must bind the promotor in order to be effective.

Light input to this model is in the form of an increase in the maximum rate of translation in response to illumination.

This model is described in J. Biol. Rhythms 14(6):433-48, 1999.