This product is an active protein and may elicit a biological response in vivo, handle with caution.
Breast tumor kinase
Breast tumour kinase
Protein tyrosine kinase 6
Protein-tyrosine kinase 6
Tyrosine protein kinase BRK
Tyrosine-protein kinase BRK
FunctionPhosphorylates KHDRBS1, KHDRBS2, KHDRBS3 and STAP2/BKS. May function as an intracellular signal transducer in epithelial tissues. Overexpression in mammary cells leads to mitogenically sensitization to EGF, and results in a partially transformed phenotype. Its presence in the nucleus appears to be linked to suppression of tumor progression.
Tissue specificityEpithelia-specific. Very high level in colon and high levels in small intestine and prostate, and low levels in some fetal tissues. Expressed at low level in some breast tumors, but not in normal breast. Also found in melanocytes. Not expressed in heart, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas.
Sequence similaritiesBelongs to the protein kinase superfamily. Tyr protein kinase family. BRK/PTK6/SIK subfamily. Contains 1 protein kinase domain. Contains 1 SH2 domain. Contains 1 SH3 domain.
Post-translational modificationsAutophosphorylated. The phosphorylation of Tyr-447 may lead to the autoinhibition of the enzyme.
Cellular localizationCytoplasm. Nucleus. Colocalizes with KHDRBS1, KHDRBS2 or KHDRBS3, within the nucleus. In secretory epithelial cells from prostate adenocarcinoma, nuclear localization is higher in low-grade and lower in high-grade regions of the tumors.