Behavior of cells with anisotropic tumbling model.

<p>(A) Distribution of cellular orientations prior to tumbles. The tumbling events are divided into 3 groups, by the number of CW-rotating motors involved in a tumble. The rose histograms are normalized by the number of counts. The inner black circle shows unbiased (isotropic) distribution as a reference. Cell orientation is given relative to the gradient. The gradient steepness is N1. (B) Average tumbling angle as a function of orientation along the gradient prior to tumbles. (C) Chemotactic drift velocity of cells in gradients of different steepness. Bars show the drift velocities of cells with 3 motors (left group) or 5 motors (right group) in the medium without a gradient (gray), in gradient N0 (blue), N1 (green) and N2 (red). Left bars show the isotropic model, right (hatched) bars – anisotropic model of tumbling. In the absence of gradient, the difference is within the error of estimation. Standard error of the mean is about 0.03. Cells in (A) and (B) have 3 motors, other parameters are as described in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1000717#pcbi-1000717-t002" target="_blank">Tab. 2</a>. The number of simulated cells is in each case.