A New Model of Synthetic Genetic Oscillator Based on Trans -Acting Repressor Ribozyme

摘要

We present a new model of synthetic genetic oscillator based on a typical motif with one positive and one negative feedback loop. The repressor is a ribozyme, rather than a protein, which acts post-transcriptionally binding and cleaving to target mRNA. The properties of the ribozyme simplify our genetic oscillator that involves only two genes, one mRNA and one activator protein, apart from the ribozyme. Moreover, the genetic oscillator generates limit cycle oscillations, essential condition for resist the effects of the stochastic fluctuations due to the inherent randomness of the chemical reactions. As example of operation, we have chosen parameter values that produce circadian period in both deterministic and stochastic simulations, and the effects of stochastic fluctuations are quantified by a period histogram and autocorrelation function. Such new biochemical network designs may yield both new behaviors and better understanding of cellular processes.