On stochastic spatial patterns and neuronal polarity

Abstract

Polarization refers to asymmetric changes in cellular organization that occur in response to external or internal signals. Although neurons can spontaneously establish and maintain asymmetric distributions of signalling molecules on the plasma membrane, it is not clear how intrinsic noise affects neuronal polarization. In this work we present a stochastic model based on endocytosis, exocytosis and lateral diffusion, to study the effects of low number of molecules, (high noise intensity), on neuronal polarization. Numerical results were obtained by solving the master equation using Gillespie?s algorithm. Our model suggests that the formation of a single pole of molecular asymmetry is very robust to noise; furthermore, in the presence of noise, neuronal polarization could occur even with reduced feedback strength.