Nature 523, 226–230 (2015); doi:10.1038/nature14582

In this Letter we omitted to include the accession number for our RNA-seq data. The data are deposited in the Sequence Read Archive database under the accession number SRP060713. Also, in our description of the basic characteristics of cycling cardiomyocytes using the CAG line (Fig. 2b), we found that their cell size tended to be smaller, although this was not statistically significant (P = 0.08749, two-tailed unpaired t-test). The P value is reported correctly in Fig. 2b, but the original text incorrectly stated that cell size was significantly smaller. Author R.C. could not be contacted for approval of the publication of this Corrigendum. These errors have been corrected in the online versions of the paper.