How and when to build a tail

In a study funded by FCT, researchers at the Gulbenkian Institute of Science (IGC) identified a gene that plays a key role in the transition between the trunk and tail in vertebrates. Moises Mallo and his team discovered that when the Gdf11 gene is inactivated in mouse embryos, they develop long trunks because the transition from trunk to tail is delayed. Conversely, 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 posterior end of the embryos, where 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, provide insight into the wide anatomical variety of vertebrates (compare a mouse with a snake, for example), but also contribute to a better understanding of human congenital malformations.