Membrane related dynamics and the formation of actin in cells growing on micro-topographies: a spatial computational model

Table 1 Key parameters in model simulations

Parameter	Type	Values used
Actin	Amount	250, 500 ⁽¹⁾
Cofilin	Amount	400, 800
Integrin	Amount	100, 200
rCofRegAppearance	Reaction rate (1st order)	0.5, 2
rCofRegDisappearance	Reaction rate (1st order)	0.5, 2
Angle deviation	Distribution	$N (0, {7.5}^{2})$ ,
		$N (0, 15^{2})$ ,
		$N (0, 30^{2})$
Surface structure	(Qualitative)	planar surface,(groves), pillars

Values were chosen after multiple experiments with values outside the given ranges had lead to either behavior similar to those reached with a combination of the above values, or to behavior not matching the wet-lab observations (e.g., very short filaments, or very long filaments in both the planar and the micro-structured setting). Cofilin activity regulation via intermediate step CofReg has been assumed above, i.e., pCofDeactAtInt =0. For actin, initial amounts are given. Additional actin was generated during the simulation (at a constant rate, such that there were 5000-6000 actin entities at the end of each simulation). Note that our actin chains are supposed to represent filament bundles and thus the proportion of actin to other actors, especially cofilin and integrin, need not correspond to realistic conditions.

ISSN: 1752-0509