Source:http://linkedlifedata.com/resource/umls/id/C0138965
NCI: CSK is a novel cytoplasmic tyrosine kinase that down regulates the tyrosine kinase activity of c-src oncoprotein through phosphorylation of the c-src carboxy terminus. Since cell transformation by SRC oncoproteins is caused by mechanisms that interfere with this phosphorylation, CSK might function as an antioncogene. The CSK gene is ubiquitously expressed. The SH3 domain of CSK associates with a proline-rich region of PEP, a protein-tyrosine phosphatase expressed in hemopoietic cells. This association is highly specific; PEP may be an effector and/or regulator of CSK in T-cells and other hemopoietic cells. (from OMIM 124095 and NCI)