Figure 1. Signal transduction via kinase-associated receptors. The receptors are drawn to illustrate their intrinsic kinase domains (rectangles) or the dual kinase domains in associated Jak kinases, and to emphasize their dimeric or heterotetrameric configurations after ligand binding. Activation of receptors induce a number of signalling pathways; activating and inhibitory interactions in these pathways are indicated. Nuclear translocation is indicated by dotted lines. Abbreviations: JAK, Janus kinase; STAT, signal transducer and activator of transcription; GAP, GTPase-activating protein; Grb2, growth factor receptor bound-2; Sos1, son of sevenless-1; MEK, mitogen-activated extracellular receptor-regulated kinase; MAP kinase, mitogen-activated protein kinase; PI3 kinase, phosphatidylinositol 3¢-kinase; Rac, Ras-related C3 substrate; PLC, phospholipase C-; SHP-2, SH2 domain-containing phosphatase-1; Smad, Sma and Mad-related. Src, Ras, Raf-1 and Akt were first discovered as oncogene products with the same names.