p21 RAS:GTP p21 RAS:GDP Activation of RAS by RasGRP1 and RasGRP3 Authored: May, B, 2011-01-03 Edited: May, B, 2010-12-18 Pubmed10777492 Pubmed10835426 Pubmed10934204 Pubmed11221888 Pubmed17283063 RasGRP1 (Roose et al. 2007) and RasGRP3 (Ohba et al. 2000, Yamashita et al. 2000, Rebhun et al. 2000, Lorenzo et al. 2001) catalyze the exchange of GDP for GTP bound by RAS. Reactome Database ID Release 431168636 Reactome, http://www.reactome.org ReactomeREACT_118807 Reviewed: Wienands, J, 2012-02-11