| Purification and Quality Control | The His-tag recombinant protein is purified by affinity chromatography in combination with FPLC columns. The purified CSK is greater than 95% homogeneous based on SDS-PAGE analysis. |
| Unit Definition (Activity) | 1 unit equals 1 nanogram of purified protein. |
| Applications | 100ng of CSK is sufficient to phosphorylated 1ug of heat-inactivated nuclear or cytoplasmic extract at 30 C for 30 minutes. For Research Use Only. |
| Formulation and Storage | The protein is in 20mM Tris-HCl pH7.9,100mM NaCl, 0.2mM EDTA, 1mM DTT and 20% glycerol. Stored at -70°C before use. Avoid repeated freeze thaw cycles. |
| Synonym | Homo sapiens c-src tyrosine kinase (CSK), transcript variant 1; MGC117393; c-src tyrosine kinase; protein-tyrosine kinase CYL. |
| Protein Sequence | MSAIQAAWPS GTECIAKYNF HGTAEQDLPF CKGDVLTIVA VTKDPNWYKA KNKVGREGII
PANYVQKREG VKAGTKLSLM PWFHGKITRE QAERLLYPPE TGLFLVREST NYPGDYTLCV
SCDGKVEHYR IMYHASKLSI DEEVYFENLM QLVEHYTSDA DGLCTRLIKP KVMEGTVAAQ
DEFYRSGWAL NMKELKLLQT IGKGEFGDVM LGDYRGNKVA VKCIKNDATA QAFLAEASVM
TQLRHSNLVQ LLGVIVEEKG GLYIVTEYMA KGSLVDYLRS RGRSVLGGDC LLKFSLDVCE
AMEYLEGNNF VHRDLAARNV LVSEDNVAKV SDFGLTKEAS STQDTGKLPV KWTAPEALRE
KKFSTKSDVW SFGILLWEIY SFGRVPYPRI PLKDVVPRVE KGYKMDAPDG CPPAVYEVMK
NCWHLDAAMR PSFLQLREQL EHIKTHELHL |
| Background | The C-terminal Src kinase (Csk) phosphorylates and down-regulates Src family tyrosine kinases Cell transformation by src oncoproteins is caused by several oncogenic mechanisms, which interfere with this phosphorylation. The CSK gene could therefore potentially function as an antioncogene.(1) The Csk-binding protein (Cbp) localizes Csk close to its substrates at the plasma membrane, and increases the specific activity of the kinase. (2) It has been reported prior to occurrence of neoplastic lesions in the colon carcinogenesis; the tumor suppressor gene C-terminal Src kinase (Csk) was down-regulated with a concomitant increase in Src activity. Furthermore, pharmacological or genetic (RNA interference) inhibition of Csk resulted in increased proliferation in colon cancer cell lines through the mitogen-activated protein kinase dependent pathway. (3) Csk, which phosphorylates tyrosine residues in the negative regulatory sites of Src family kinases, down-regulated Fyn- and Lck-mediated stimulation of the serum response element and Fyn-mediated enhancement of IL-2 promoter activity. (4) |
| Image of SDS-PAGE |  |
