Fig. 3.

System dynamics and stability in 2i/LIF (PD = Chiron = 2 AU, Nanog transcriptional noise reduced by 20%) a Steady-state distribution of Nanog simulated in 1000 cells, showing that approximately 90% and 10% of the cells are in the NH and NL states, respectively. b Four representative time-course simulations of Nanog (blue line) and Oct4-Sox2 (red line) in single cells over 15 h. Similarly to the serum/LIF case, Oct4-Sox2 dimer concentration remains fairly constant compared to Nanog. The horizontal black dotted line represents the threshold between NH and NL. c Continuation of Nanog steady-state for the deterministic system (no noise). Blue lines are stable steady-states, while the red line is unstable. The maximal transcription rate, s ₄ (dotted black line), intersects both NH and NL steady-states, though is very close to the saddle-node bifurcation. d Sorting simulation: 1000 cells in the NH or NL state are simulated over 4 days, and the proportion of cells in the NH state is recorded every 12 h (n = 10, shaded areas indicate standard deviation). Cells restore the steady-state distribution of approximately 90% NH and 10% NL