Recombinant human Janus kinase 3 (JAK3), protein kinase domain, 10 µg

Background: Janus Kinase 3 (JAK3) belongs to the Jak family of non-receptor tyrosine kinases comprises four structurally related kinases: Jak1, Jak2, Jak3, and Tyk2. JAK3 is primarily expressed in hematopoietic cells and involved in various processes such as cell growth, development, or differentiation. The JAK3 protein presents seven JAK homology (JH) domains common with the other JAK proteins. The JH1 domain is a kinase domain whose activity is regulated in part by phosphorylation of key tyrosine residues (Y980 and Y981) in its kinase activation loop. N-terminal to JH1 is the catalytically inactive pseudo-kinase domain (JH2), which represents a unique feature of JAK proteins. The JH2 is thought to interact with signal transducers and activators of transcription (STAT) and negatively regulate kinase activity of the JH1 domain. Upon interaction to the heteromeric cytokine receptors, including IL2- IL4-, IL7-, IL9-, IL-13, IL15-, and IL21-receptor subunit called common γc JAK3 proteins become autophosphorylated and docking sites for signaling molecules, including STAT factors, Phosphatidyl-Inositol 3-Kinase (PI3K) and Insulin Receptor Substrate (IRS) were provided. Phosphorylation of STAT factors allows their translocation to the nucleus to regulate gene transcription of a wide variety of target genes. Recent data revealed that abnormal activation of JAK3 due to activating mutations is found in human hematological malignancies, including acute megakaryoblastic leukemia (AMKL) and cutaneous T cell lymphoma (CTCL).

recombinant human JAK3 (amino acids I781-S1124 (as in GenBank entry NM_000215), N-terminally fused to GST-HIS6-Thrombin cleavage site

Theoretical MW : 68.4 kDa (fusion proteins)
Expression system: Sf9 cells
Purification: One-step affinity purification using glutathione agarose
Storage buffer: 50 mM Tris-HCl, pH 8.0; 100 mM NaCl, 5 mM DTT, 4 mM reduced glutathione, 20% glycerol
Protein concentration: 0.213 mg/ml (Bradford method using BSA as standard protein)
Method for determination of Km value & specific activity: Filter binding assay MAFC membrane
Specific activity : 8,000 pmol/mg min

Entrez Gene ID: 3718
UniprotKB: P552333

Ordering information: shipped on dry ice

Product specififc literature

Cornejo MG1, Boggon TJ, Mercher T. (2009) "JAK3: a two-faced player in hematological disorders."Int J Biochem Cell Biol. 2009 Dec;41(12):2376-9.

Wu W1, Sun XH. (2012) "Janus kinase 3: the controller and the controlled."Acta Biochim Biophys Sin (Shanghai). 2012 Mar;44(3):187-96.