Reprogramming is not equivalent to reprogramming

“Oct4”, the main switch protein of pluripotency is not essential for totipotency

Reprogramming somatic cells to all-rounder cells is on everybody’s lips – last year the Nobel Prize for Physiology or Medicine was awarded to two scientists, Sir John Gurdon and Shinya Yamanaka, for their achievements in the field of reprogramming. Yamanaka showed in 2006 that somatic cells can be reprogrammed to a pluripotent state with the help of four factors, one of them being Oct4. More than forty years ago, Gurdon had demonstrated in his cloning experiments with frog’s eggs that somatic cells can, after all, be reprogrammed – to totipotency that is. Now scientists of Hans Schöler’s group at the Max Planck Institute (MPI) for Molecular Biomedicine in Münster have demonstrated that reprogramming with factors (to pluripotency) and reprogramming with an egg cell (either by fertilisation or by cloning) are fundamentally different: Oct4, the main switch protein in Yamanaka-style reprogramming, is not required to establish totipotency (Nature Cell Biology, Epub ahead of print on August 11, 2013).