Correction to: Cell Research (2012) 22:1640–1649. doi:https://doi.org/10.1038/cr.2012.160; published online 27 November 2012

We apologize for an error that we just found in the paper published in 2012. The first column of Figure 4A and the third column of Figure 4D were inadvertently duplicated. A corrected version of Figure 4D is provided below. Any conclusions are not affected by this error, but we apologize for not detecting it before publication.