ATP + L-tyrosyl-[protein] = ADP + H(+) + O-phospho-L-tyrosyl-[protein] This protein is synthesized as an Env-Ryk polyprotein. An Env-Ryk precursor fusion protein is first synthesized and then cellular protease cleaves this precursor into gp85 and the putative oncogene termed gp69 (gp37-Ryk). Belongs to the protein kinase superfamily. Tyr protein kinase family. AXL/UFO subfamily.