How and when to build a tail

In a study funded by the FCT, researchers from the Instituto Gulbenkian de Ciência (IGC) have identified a gene that is central to the transition between trunk and tail in vertebrates. Moises Mallo and his team found that when the Gdf11 gene is inactivated in mouse embryos, they develop long trunks because the transition from trunk to tail is delayed. On the other hand, if Gdf11 is activated prematurely, the embryos have extremely short trunks, with the hind legs very close to the front legs. The researchers revealed a delicate balance occurring at the rear end of the embryos, in which the Gdf11 gene induces immature cells (called progenitors) to transform into hind leg and tail cells. These results, published in the prestigious journal Developmental Cell, make it possible to understand the great anatomical variety of vertebrates (compare a mouse with a copperhead, for example), but also contribute to a better understanding of human congenital malformations.