ABSTRACT

GAP was first described in 1987 as a protein present in cytosolic fractions of Xenopus oocytes and NIH 3T3 cells, able to stimulate the GTPase activity of mammalian normal p21ras. 1 This exciting finding explained at that time the differences found in the transforming ability of some oncogenic forms of ras. 1 Since then, much effort has been made to determine its precise function.