Abstract Submitted for the MAR08 Meeting of The American Physical Society
Subhadip Raychaudhuri · 2007
A minimal stochastic model of cell death signaling SUBHADIP RAYCHAUDHURI | Cell death (apoptosis) is mediated by a complex intracellular signaling network that involves a large number of components. We propose a minimal model of signaling network that can sense the strength of any extracellular stimuli such as the concentration of ligands and adapt to a ∞uctuating environment. Based on stochastic simulations we show that a three step slow, fast, slow pathway is enough to generate large cell to cell ∞uctuations under the conditions of weak stimulus. Such cell to cell stochastic ∞uctuations persist even in the presence of large number of molecules and cannot be captured by deterministic difierential equation based models. We develop a probability distribution based approach that can characterize the stochastic ∞uctuations in such inherently stochastic signaling network. Interestingly, our results match with those obtained from kinetic Monte Carlo simulation of the full scale apoptotic network. Hence, our minimal signaling network can serve as a cell type independent general model of apoptosis signaling. We also discuss implications of our probability distribution based approach for diseases such as cancer that can result from disrupted apoptotic balance.