Phospho-Jak2 (Tyr221) Antibody

• 产品编号：CST-3774S      品牌：CST       原厂货号：3774S
• 产品分类：抗体 > 一抗 > 磷酸化抗体
• 应用分类：

描述：

Phospho-Jak2 (Tyr221) Antibody 只能检测内源的在Tyr221位点磷酸化的Jak2蛋白。此多克隆抗体是通过合成人源对应的Jak2 Tyr221位点周围的磷肽段来免疫动物而获得。抗体是通过protein A和多肽亲和层析纯化。Janus家族中的酪氨酸激酶成员(Jak1, Jak2, Jak3和Tyk2)通过配体结合到一些相关的细胞因子受体上而被激活（1）。除了细胞因子受体的激活方式，Jak蛋白能自身磷酸化和磷酸化与其相关的受体从而为信号蛋白提供多个结合位点。这些信号蛋白如Stats (2), Shc (3), 胰岛素受体底物(4) and 成簇黏附激酶 (FAK) (5)都是典型的含有SH2 或者其它的磷酸化酪氨酸结合区域。JAK2在特定细胞因子信号中，在假定的活化环的Tyr1007/ 1008位点发生自身磷酸化（6）。 Tyr221和570也被证明是显着的磷酸化位点（7,8）。突变分析表明，磷酸化Tyr221可能增加激酶活性，而JH2抑制域内的Tyr570的磷酸化，可能有助于抑制Jak2的活动。此外，Tyr813被鉴定为自身磷酸化位点，对于JAK2由含SH2结构域的蛋白SH2-Bβ（9）的激活是至关重要的。

1. Leonard, W.J. and O'Shea, J.J. (1998) Annu Rev Immunol 16, 293-322.
2. Darnell, J.E. (1997) Science 277, 1630-5.
3. VanderKuur, J. et al. (1995) J Biol Chem 270, 7587-93.
4. Argetsinger, L.S. et al. (1995) J Biol Chem 270, 14685-92.
5. Zhu, T. et al. (1998) J Biol Chem 273, 10682-9.
6. Gauzzi, M.C. et al. (1996) J Biol Chem 271, 20494-500.
7. Argetsinger, L.S. et al. (2004) Mol Cell Biol 24, 4955-67.
8. Feener, E.P. et al. (2004) Mol Cell Biol 24, 4968-78.
9. Kurzer, J.H. et al. (2004) Mol Cell Biol 24, 4557-70.

原厂资料：

Specificity / Sensitivity

Phospho-Jak2 (Tyr221) Antibody detects endogenous levels of Jak2 only when phosphorylated at Tyr221.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr221 of human Jak2 protein. Antibodies are purified by protein A and peptide affinity chromatography.

Background

Members of the Janus family of tyrosine kinases (Jak1, Jak2, Jak3 and Tyk2) are activated by ligands binding to a number of associated cytokine receptors (1). Upon cytokine receptor activation, Jak proteins become autophosphorylated and phosphorylate their associated receptors to provide multiple binding sites for signaling proteins. These associated signaling proteins, such as Stats (2), Shc (3), insulin receptor substrates (4) and focal adhesion kinase (FAK) (5), typically contain SH2 or other phospho-tyrosine-binding domains.

Jak2 is autophosphorylated at Tyr1007/1008 in the putative activation loop during cytokine signaling (6). Tyr221 and 570 have also been shown to be prominent sites for autophosphorylation (7,8). Mutational analysis suggests that phosphorylation at Tyr221 may increase kinase activity, while phosphorylation at Tyr570, which lies within the JH2 inhibitory domain, may contribute to inhibiting Jak2 activity. In addition, Tyr813 was identified as a site for autophosphorylation critical for the activation of Jak2 by the SH2 domain-containing protein SH2-B β (9).

1. Leonard, W.J. and O'Shea, J.J. (1998) Annu Rev Immunol 16, 293-322.
2. Darnell, J.E. (1997) Science 277, 1630-5.
3. VanderKuur, J. et al. (1995) J Biol Chem 270, 7587-93.
4. Argetsinger, L.S. et al. (1995) J Biol Chem 270, 14685-92.
5. Zhu, T. et al. (1998) J Biol Chem 273, 10682-9.
6. Gauzzi, M.C. et al. (1996) J Biol Chem 271, 20494-500.
7. Argetsinger, L.S. et al. (2004) Mol Cell Biol 24, 4955-67.
8. Feener, E.P. et al. (2004) Mol Cell Biol 24, 4968-78.
9. Kurzer, J.H. et al. (2004) Mol Cell Biol 24, 4557-70.

注意事项：

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at –20°C. Do not aliquot the antibody.