Vol. 216, No. 9, September 4, 2017. 10.1083/jcb.201702013.

The authors noticed that the cartoons in Figs. 3 and 8 lacked some of the intensity labels of the signals shown in the images below. While this oversight does not affect any conclusions, nor does it affect the raw data shown in the images of the cells in the figures, the authors wish to add the missing labels to the cartoons in Fig. 3, B1 and B2, and Fig. 8 A for the sake of completion.

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