The effect of mRNA diffusion on stochastic bursts in gene transcription

The positive feedback between messenger ribonucleic acid (mRNA) and regulatory-protein production may result in bistability and stochastic "bursts" in gene transcription. The temporal kinetics of such bursts have already been simulated in detail. We (i) show that the applicability of the temporal models may be limited due to relatively slow mRNA and/or protein diffusion and (ii) present the first 3D Monte-Carlo simulations indicating that with explicit mRNA diffusion the bursts may be much more irregular, the periods between bursts may be much shorter, and, depending on the circumstances, the burst window may be reduced or extended.