Orphan receptor tyrosine kinase (RTK) that may activate several downstream signaling pathways related to cell differentiation, proliferation, growth and survival including the PI3 kinase-mTOR signaling pathway. Mediates the phosphorylation of PTPN11, an activator of this pathway. May also phosphorylate and activate the transcription factor STAT3 to control anchorage-independent cell growth. Mediates the phosphorylation and the activation of VAV3, a guanine nucleotide exchange factor regulating cell morphology. May activate other downstream signaling proteins including AKT1, MAPK1, MAPK3, IRS1, and PLCG2. ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] Interacts with VAV3; constitutive interaction mediating VAV3 phosphorylation. Highest expression in kidney. Also expressed in gonad, thymus, bursa, brain and kidney. Belongs to the protein kinase superfamily. Tyr protein kinase family. Insulin receptor subfamily.