RESEARCH ARTICLE Stochasticity in the miR-9/Hes1 oscillatory network can account for clonal heterogeneity in the timing of differentiation Nick E Phillips1, Cerys S Manning1†, Tom Pettini1†, Veronica Biga1†, Elli Marinopoulou1†, Peter Stanley1†, James Boyd1, James Bagnall1, Pawel Paszek1, David G Spiller1, Michael RH White1, Marc Goodfellow2,3,4, Tobias Galla5, Magnus Rattray1, Nancy Papalopulu1* 1Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom; 2College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom; 3Centre for Biomedical Modelling and Analysis, University of Exeter, Exeter, United Kingdom; 4EPSRC Centre for Predictive Modelling in Healthcare, University of Exeter, Exeter, United Kingdom; 5Theoretical Physics, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom Abstract Recent studies suggest that cells make stochastic choices with respect to differentiation or division. However, the molecular mechanism underlying such stochasticity is unknown. We previously proposed that the timing of vertebrate neuronal differentiation is *For correspondence: nancy. regulated by molecular oscillations of a transcriptional repressor, HES1, tuned by a post-
[email protected] transcriptional repressor, miR-9. Here, we computationally model the effects of intrinsic noise on the Hes1/miR-9 oscillator as a consequence of low molecular numbers of interacting species, †These authors contributed determined experimentally. We report that increased stochasticity spreads the timing of equally to this work differentiation in a population, such that initially equivalent cells differentiate over a period of time. Competing interests: The Surprisingly, inherent stochasticity also increases the robustness of the progenitor state and lessens authors declare that no the impact of unequal, random distribution of molecules at cell division on the temporal spread of competing interests exist.