PAK Active RAC1/CDC42 PAK bound to Rac1 and Cdc42 Activation of PAK by Rac1 and Cdc42 Authored: Garapati, P V, 2008-07-16 14:42:16 Edited: Garapati, P V, 2008-12-16 11:12:19 In its unbound state PAK is maintained in an inactive conformation through intra domain interactions. On stimulation PAK is translocated to the plasma membrane where it specifically interacts with Rho family GTP-binding proteins Rac1-GTP and Cdc42-GTP. All PAK isoforms are direct effectors of the Rac and Cdc42. Rac and Cdc42 bind to a highly conserved motif in the amino terminus of PAK known as p21-binding domain (PBD) or Cdc42/Rac interactive binding (CRIB) domain. This binding is thought to induce a conformational change in PAK that relieves autoinhibition of the catalytic carboxy terminal domain, thereby inducing autophosphorylation at several sites and enabling the phosphorylation of exogenous substrates. Pubmed10470034 Pubmed19513348 Reactome Database ID Release 43389788 Reactome, http://www.reactome.org ReactomeREACT_19246 Reviewed: Bluestone, JA, Esensten, J, 2009-06-01 18:47:33 PAK homodimer