There was an error published in J. Cell Sci.119, 1307-1319.

The corresponding author regrets to have omitted, and wishes to properly acknowledge, Chris Wiggins and Jake Hofman for work presented in this paper.

Chris Wiggins (Applied Physics and Applied Mathematics Department, Columbia University) and Jake Hofman (graduate student in the Department of Physics, Columbia University) designed and developed several thousand original lines of code in the programming language MATLAB to produce the analysis program used in the data analysis shown in Fig. 1. Since their contribution was substantial, they should have been listed as co-authoring this work. The correct header of this article is shown above.

Moreover, the reference in Fig. 1 that the methods used were those described by Giannone et al. (Giannone et al., 2004) is wrong. Instead, the analysis used the novel MATLAB program developed by C.H.W. and J.M.H.

The corresponding author apologizes for these errors.