A NEW REGULATORY INTERACTION SUGGESTED BY SIMULATIONS FOR CIRCADIAN GENETIC CONTROL MECHANISM IN MAMMALS

摘要

Knowledge on molecular biological systems is increasing at an amazing pace. It is becoming harder to intuitively evaluate the significance of each interaction between molecules of the complex biological systems. Hence we need to develop an efficient mathematical method to explore the biological mechanism. In this paper, we employed hybrid functional Petri net to analyze the circadian genetic control mechanism, which is feedback loops of clock genes and generates endogenous near 24 hour rhythms in mammals. Based on the available biological data, we constructed a model and, by using Genomic Object Net, we performed computer simulations for time courses of clock gene transcription and translation. Although the original model successfully reproduced most of the circadian genetic control mechanism, two discrepancies remained despite wide selection of the parameters. We found that addition of an hypothetical path into the original model successfully simulated time courses and phase relations among clockgenes. This also demonstrates usefulness of hybrid functional Petri net approach to biological systems.