Engelsk definition
A receptor tyrosine kinase that is essential for development and differentiation of the nervous system in response to secreted growth factors. It phosphorylates the first tyrosine of the Y-x-x-x-Y-Y motif of targets that include PROTO-ONCOGENE PROTEINS C-CBL; INSULIN RECEPTOR SUBSTRATE-1; and MITOGEN-ACTIVATED PROTEIN KINASES, leading to activation of the MAPK signaling pathway and cell proliferation. A chromosomal aberration involving the ALK gene results in its constitutive expression in some cases of NON-HODGKIN LYMPHOMA.