PathwayStep631 PathwayStep630 PathwayStep6662 PathwayStep6664 PathwayStep6663 PathwayStep6666 PathwayStep6665 Activation of Rap1 by membrane-associated GEFs Activation of Rap1 by cytosolic GEFs Rap1 sequesters Raf1 to inhibit ERK cascade Rap1 signal termination by Rap1GAPs PKA/PKG phosphorylate Rap1GAP2 14-3-3 proteins beta and zeta bind and inhibit Rap1Gap2 Activation of EPACs by cAMP Rap1 signalling Authored: Akkerman, JW, 2009-06-03 Edited: Jupe, S, 2010-09-01 Pubmed16076873 Rap1 (Ras-proximate-1) is a small G protein in the Ras superfamily. Like all G proteins, Rap1 is activated when bound GDP is exchanged for GTP. Rap1 is targeted to lipid membranes by the covalent attachment of lipid moieties to its carboxyl terminus. Movement of Rap1 from endosomal membranes to the plasma membrane upon activation has been reported in several cell types including Jurkat T cells and megakaryocytes. On activation, Rap1 undergoes conformational changes that facilitate recruitment of a variety of effectors, triggering it's participation in integrin signaling, ERK activation, and others. Reactome Database ID Release 43392517 Reactome, http://www.reactome.org ReactomeREACT_23898 Reviewed: Heemskerk, JW, 2010-09-01