Nat. Cell Biol. 15, 461–471 (2013); published online 7 April 2013; corrected online 23 April 2013

In the version of this Article originally published, labels were incorrectly aligned to the blots in Fig. 6c,d. The correct figures are shown below. Furthermore, the middle initial of the author Elaine C. Thomas was missing. These errors have been corrected in the PDF and HTML versions.