Nat. Chem. Biol. 13, 1253–1260 (2017); published online 16 October 2017; corrected after print 1 December 2017

In the version of this article initially published, the label colors for p-NF and p-IF in the key for Figure 4c were transposed. The cyan bars should correspond to p-NF and the fuchsia bars to p-IF. The error has been corrected in the HTML and PDF versions of the article.