Controlling the transition between generations

Rafal Ciosk and his group at the FMI have identified an important regulator of the transition from germ cell to embryonic cell. LIN-41 prevents the premature onset of embryonic transcription in oocytes poised for embryonic development, thus ensuring a successful passage between generations. This finding also holds promise for efforts to reprogram differentiated human cells into induced pluripotent stem cells. Fertilization triggers one of life's most sweeping transitions - the transition from one generation to the next and, most intriguingly for developmental biologists, from unipotent germ cells to pluripotent embryonic cells. During this transition, fully differentiated and totally specialized reproductive cells (oocytes and sperms) morph into embryonic cells with an unlimited potential to give rise, once again, to all the specialized cells in the body. It is as if a seasoned astronaut suddenly gained the potential to become a concert pianist, car mechanic, Formula One pilot, banker, physician or philosopher. A better understanding of this transition is essential for progress in stem cell therapy and regenerative medicine, where scientists are currently trying to coax fully differentiated cells, such as epithelial cells, into a more pluripotent state.