Top - Model for action of Kdm3b and 5hmC during pre-iPSC to iPSC conversion. Kdm3b mediated demethylation of H3K9me2 and 5hmC processing allows recruitment of POU5F1 and pluripotency gene upregulation. In Kdm3b deleted pre-iPSCs, 5hmC is maintained and prevents POU5F1 binding at specific genes. Bottom - Distinct temporal expression of Tet1 and Tet2 during reprogramming. 