. "Authored: Garapati, P V, 2009-03-23 09:59:28"^^ . "Edited: Garapati, P V, 2009-03-23 10:00:07"^^ . "Reviewed: Kumanogoh, A, Kikutani, H, 2009-09-01"^^ . "The best characterized receptors for mediating semaphorin signaling are members of the neuropilin and plexin families of transmembrane proteins. Neuropilins form complexes with Plexin-A which in turn can act as a signaling moiety. Also, when complexed with neuropilin-1, plexin-A1 can associate directly with the FERM domain containing guanine nucleotide exchange factor (GEF) FARP2. FARP2 exerts GEF activity for Rac but not Cdc42 and Rho."^^ . . . . . . "Plexin-A binds to neuropilin-1"^^ . . . . .