Guo-Liang Xu, Duanqing Pei and colleagues show that during induced pluripotent cell reprogramming Tet1 regulates 5-hydroxymethylcytosine levels at loci critical for mesenchymal-to-epithelial transition in a vitamin C–dependent fashion. They also show that Tet1 either enhances or inhibits somatic cell reprogramming, depending on the absence or presence of vitamin C, respectively.
- Jiekai Chen
- Lin Guo
- Duanqing Pei