<n0:ComplexDefinition xmlns:n0="http://ncicb.nci.nih.gov/xml/owl/EVS/ComplexProperties.xsd#"><n0:def-definition>Human Protein-Kinase Oncogenes are mutated variants of Kinase Family Genes, which encode diverse Protein Kinases. Protein kinase enzymes catalyze the conversion of a protein to a phosphoprotein by covalently transferring the terminal, gamma phosphate group from ATP to a variety of substrates that typically play key regulatory roles in diverse cellular functions. Protein-Kinase oncogenes disrupt normal cell function.</n0:def-definition><n0:def-source>NCI</n0:def-source></n0:ComplexDefinition>