Morphogen transport is a biological process, occurring in the tissue of
living organisms, which is a determining step in cell differentiation. We
present rigorous analysis of a simple model of this process, which is a system
coupling parabolic PDE with ODE. We prove existence and uniqueness of solutions
for both stationary and evolution problems. Moreover we show that the solution
converges exponentially to the equilibrium in C1×C0 topology. We
prove all results for arbitrary dimension of the domain. Our results improve
significantly previously known results for the same model in the case of one
dimensional domain