Non-Receptor Tyrosine Kinase Biology

Non-receptor tyrosine kinases (non-specific, cytoplasmic, protein tyrosine kinases (PTKs)), found in all metazoans, are phosphotransferase enzymes that transfer a phosphate group from ATP to a tyrosine amino acid residue creating phosphotyrosine and ADP. Major classes of non-receptor tyrosine kinases include Src, Abl and Jak. Phosphorylation of proteins by nonreceptor tyrosine kinases is reversible, and often used to control intracellular signals to the nucleus by inducing conformational changes in the active binding site of the phosphorylated proteins, causing activation or inhibition of activity. PTKs can regulate cell differentiation, cell division, cell adhesion, stress responses, embryonic development, cell growth, ion transport, extracellular signaling and other cellular processes. Polyclonal affinity isolated antibodies or antiserum IgG fraction antibodies have been developed against adaptor proteins such as RACK Proteins, Signal-Regulatory Proteins SIRPA1 (SHPS-1), and Src Homology 2-Containing Inositol Phosphatase (SHIP). Protein tyrosine kinase inhibitors are drug targets for cancer, inflammatory, metabolic and neurodegenerative diseases.