Mathematical models for the cellular concentrations of cyclin and MPF

Several mathematical models have been proposed for regulation of the cell cycle in early embryos by cyclin and maturation-promoting factor (MPF). In this paper the previously proposed models for cyclin and MPF activity are analyzed, and the validity of those models based on the mathematical behavior of their solutions and on physical considerations are discussed. In addition, three further models are proposed that exhibit the periodic behavior necessary for modeling the mitotic clock but that do not have certain of the limitations of the other models.