DNA replication licensing in stem cells: Gatekeeping the commitment to proliferation.

Carroll et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201708023) developed a method to assess DNA replication licensing in tissues. They show that intestinal stem cells within wild-type crypts, but not in crypts with cancer-causing mutations, are largely unlicensed, suggesting that licensing may represent a rate-limiting step in the commitment to proliferation.