Phospho-Btk (Tyr223) Antibody

• 产品编号：CST-5082P      品牌：Cell Signaling Technology       原厂货号：5082P
• 产品分类：抗体 > 一抗 > 磷酸化抗体
• 应用分类：

描述：

Phospho-Btk (Tyr223) 抗体只能检测内源的在Tyr223位点磷酸化的Btk蛋白。此多克隆抗体是通过合成人源对应的Btk Tyr223位点周围的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。Bruton's 酪氨酸激酶 (Btk)是细胞质激酶Btk/Tec家族的一员。与Btk家族的其它成员一样，它包含了血小板-白细胞C激酶底物同系(PH) 区域和，Src同系的SH3 和 SH2 区域。Btk在 B 细胞的发育过程中起了重要的作用 (1,2)。 B 细胞通过各种配体的激活总是伴随着PH 区域结合到磷脂酰肌醇-3,4,5-三磷酸化介导的Btk蛋白向膜定位 (3-5)。Btk定位于细胞膜后具有活性，并瞬间磷酸化两个酪氨酸残基Tyr551 和 Tyr223。位于活性环上的Tyr551位点被Src家族酪氨酸激酶转磷酸化，导致了SH3区域 Tyr223 位点的自磷酸化, 这对B 细胞的完全激活非常重要(6,7)。PKCβ通过磷酸化Btk的Ser180位点而负调控Btk的激活，并导致了细胞膜招募能力的降低，磷酸根的转移和接下来的激活(8)。The PKC 的抑制信号看起来是B细胞受体信号保持Btk最合适活性的中的重要决定因素(8)。

1. Khan, W.N. (2001) Immunol Res 23, 147-56.
2. Lewis, C.M. et al. (2001) Curr Opin Immunol 13, 317-25.
3. Salim, K. et al. (1996) EMBO J 15, 6241-50.
4. Rameh, L.E. et al. (1997) J Biol Chem 272, 22059-66.
5. Várnai, P. et al. (1999) J Biol Chem 274, 10983-9.
6. Rawlings, D.J. et al. (1996) Science 271, 822-5.
7. Park, H. et al. (1996) Immunity 4, 515-25.
8. Kang, S.W. et al. (2001) EMBO J 20, 5692-702.

原厂资料：

Homology

Species predicted to react based on 100% sequence homology: Mouse, Rat

Specificity / Sensitivity

Phospho-Btk (Tyr223) Antibody detects endogenous levels of Btk only when phosphorylated at Tyr223.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr223 of human Btk protein. Antibodies are purified by protein A and peptide affinity chromatography.

Background

Bruton's tyrosine kinase (Btk) is a member of the Btk/Tec family of cytoplasmic tyrosine kinases. Like other Btk family members, it contains a pleckstrin homology (PH) domain, and Src homology SH3 and SH2 domains. Btk plays an important role in B cell development (1,2). Activation of B cells by various ligands is accompanied by Btk membrane translocation mediated by its PH domain binding to phosphatidylinositol-3,4,5-trisphosphate (3-5). The membrane-located Btk is active and associated with transient phosphorylation of two tyrosine residues, Tyr551 and Tyr223. Tyr551 in the activation loop is transphosphorylated by the Src family tyrosine kinase, leading to autophosphorylation at Tyr223 within the SH3 domain, which is necessary for full activation (6,7). The activation of Btk is negatively regulated by PKCβ through phosphorylation of Btk at Ser180, which results in reduced membrane recruitment, transphosphorylation and subsequent activation (8). The PKC inhibitory signal is likely to be a key determinant of the B-cell receptor signaling threshold to maintain optimal Btk activity (8).

1. Khan, W.N. (2001) Immunol Res 23, 147-56.
2. Lewis, C.M. et al. (2001) Curr Opin Immunol 13, 317-25.
3. Salim, K. et al. (1996) EMBO J 15, 6241-50.
4. Rameh, L.E. et al. (1997) J Biol Chem 272, 22059-66.
5. Várnai, P. et al. (1999) J Biol Chem 274, 10983-9.
6. Rawlings, D.J. et al. (1996) Science 271, 822-5.
7. Park, H. et al. (1996) Immunity 4, 515-25.
8. Kang, S.W. et al. (2001) EMBO J 20, 5692-702.

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.