Correction to: Cell Research (2011) 21:1750–1754. doi:10.1038/cr.2011.151; published online 6 September 2011

In our discussion of the role of Argonaute proteins in stem cell regulation, we inadvertently omitted an important earlier contribution by Agata's group1. Through testing conserved post-transcriptional regulators in the planarian Dugesia japonica, their study reports that Djago2 is required to maintain stem cell identity.

We regret any inconvenience caused by this omission.