( mbryos to inactivate the native PouV p...)Study shows frogs can play key role in stem cell research

When the scientists looked closely at these embryos, they found that cells had become specialised before they were supposed to ?before the embryo was ready for them. Consequently, the structures they make are severely affected.

This suggests that the PouV proteins are holding the cells in an uncommitted state, waiting for the time to come when they will decide what type of cell they are going to be. This is probably what Oct4 is doing in mouse and human embryonic stem cells.

The findings are also interesting because they highlight that the remarkable capacity of embryonic stem cells to divide without limit is at least 300 million years old. "It was very exciting, and humbling, to find that the proteins from such an ancient animal such as the frog can rescue the behaviour of 'modern' mouse embryonic stem cells. It told us so much about where this behaviour comes from, and how long ago," said Dr Morrison.

Dr Josh Brickman, group leader at the Institute for Stem Cell research said: "Our results show that mammals have adopted the function of the amphibian PouV proteins to maintain their embryonic stem cells. These features of dividing without limit and giving rise to many types of cell are thus ancient features of early embryonic cells, crucial for the correct development of both frogs and humans."