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A. Arnold, E. Sevcsik, G. Schütz:
"Monte Carlo simulations of protein micropatterning in biomembranes: effects of immobile sticky obstacles";
Journal of Physics D: Applied Physics, 49 (2016), 3640021 - 36400211.

Single molecule trajectories of lipids and proteins can yield valuable information about
the nanoscopic organization of the plasma membrane itself. The interpretation of such
trajectories, however, is complicated, as the mobility of molecules can be affected by the
presence of immobile obstacles, and the transient binding of the tracers to these obstacles.
We have previously developed a micropatterning approach that allows for immobilizing
a plasma membrane protein and probing the diffusional behavior of a putative interaction
partner in living cells. Here, we provide guidelines on how this micropatterning
approach can be extended to quantify interaction parameters between plasma membrane
constituents in their natural environment. We simulated a patterned membrane system
and evaluated the effect of different surface densities of patterned immobile obstacles
on the relative mobility as well as the surface density of diffusing tracers. In the case of
inert obstacles, the size of the obstacle can be assessed from its surface density at the
percolation threshold, which in turn can be extracted from the diffusion behavior of the
tracer. For sticky obstacles, 2D dissociation constants can be determined from the tracer
diffusion or surface density.

protein micropatterning, single molecule diffusion, single molecule tracking, Monte Carlo simulation, biomembranes