Description_x000D_ General description_x000D_ JAK3 is a member of the JAK family of tyrosine kinases involved in cytokine receptor-mediated intracellular signal transduction. Low levels of JAK3 expression is detected in immature hematopoietic cells, which dramatically increases during terminal differentiation of these cells suggesting a role of JAK3 in the differentiation of hematopoietic cells. Mutations in JAK3 are associated with autosomal SCID (severe combined immunodeficiency disease). Mice lacking JAK3 show a severe block in B-cell development at the pre-B stage in bone marrow suggesting that JAK3 is critical for the progression of B-cell development in the bone marrow._x000D_ Physical form_x000D_ Supplied in 50mM Tris-HCl, pH 7.5, 150mM NaCl, 10mM glutathione, 0.1mM EDTA, 0.25mM DTT, 0.1mM PMSF, 25% glycerol._x000D_ Preparation Note_x000D_ after opening, aliquot into smaller quantities and store at -70 °C. Avoid repeating handling and multiple freeze/thaw cycles_x000D_ Legal Information_x000D_ PRECISIO is a registered trademark of Sigma-Aldrich Co. LLC