Nature Cell Biol. 11, 1128–1134 (2009); published online 23 August 2009; corrected after print 28 August 2009

In the version of this article initially published online and in print, the word Tip60 was incorrectly used instead of Pirh2 in the legend for Fig. 2b. This error has been corrected in the HTML and PDF versions of the article.