Spontaneous separation of bi-stable biochemical systems into spatial domains of opposite phases

摘要: Bi-stable chemical systems are the basic building blocks for intracellular memory and cell fate decision circuits. These circuits built from molecules, which present at low copy numbers slowly diffusing in complex geometries. The stochastic reaction-diffusion kinetics of a double-negative feedback system MAPK phosphorylation-dephosphorylation is analysed with Monte-Carlo simulations master equation. results show geometry reaction compartments to be important both duration locality biochemical memory. Rules when lose global hysteresis by spontaneous separation into spatial domains opposite phases formulated terms geometrical constraints, diffusion rates attractor escape times. analysis facilitated new efficient algorithm exact sampling Markov process corresponding