PathScan? Phospho-HER3/ErbB3 (panTyr) Sandwich ELISA Kit

• 产品编号：CST-7890C      品牌：CST       原厂货号：7890C
• 产品分类：ELISA及其它免疫分析 > ELISA > ELISA检测试剂盒
• 应用分类：

其它组分：

描述：

CST公司的PathScan® Phospho-HER3/ErbB3 (panTyr) Sandwich ELISA Kit #7890仅用于检测内源酪氨酸位点磷酸化的HER3/ErbB3蛋白的表达（如图１）。图2显示试剂盒的灵敏度。本试剂盒不与其它ErbB家族的蛋白发生交叉反应（数据未显示）。内部检测显示，本试剂盒能检测列举出的物种蛋白，但不排除用于其它物种同源蛋白检测的可能。CST公司的PathScan® Phospho-HER3/ErbB3 (panTyr) Sandwich ELISA Kit利用固相双抗夹心酶联免疫检测法对内源性酪氨酸磷酸化HER3/ErbB3的表达进行检测。微孔中已经包被了抗体HER3/ErbB3鼠抗体，与细胞裂解液共孵育后，磷酸化的和未磷酸化的HER3/ErbB3受体蛋白均能被包被抗体捕获。多次洗板之后，加入抗体酪氨酸磷酸化兔检测抗体对被捕获的酪氨酸磷酸化HER3/ErbB3蛋白进行检测，然后加入抗兔IgG, HRP偶联抗体对检测抗体进行识别，最后加入HRP的底物TMB进行显色反应。按照相对光单位，发射光强度与酪氨酸位点磷酸化的HER3/ErbB3蛋白的量成正比。HER3/ErbB3是ErbB酪氨酸激酶受体蛋白家族的成员之一，但却没有酪氨酸激酶活性。ErbB3的酪氨酸位点磷酸化依赖于其它ErbB酪氨酸激酶。与配体结合后，ErbB3与其它ErbB蛋白形成异二聚体,并且其酪氨酸位点能够被激活的ErbB激酶磷酸化（1，2）。在ErbB3的羧基端至少有9个潜在的酪氨酸磷酸化位点。这些位点都是信号转导蛋白一致的结合位点，这些蛋白包括Src家族的分子，Grb2, 和PI3K激酶的p85亚基，它们都能参与ErbB的下游信号调节(3)。ErbB3 的Tyr1222和Tyr1289残基都位于一个YXXM基序上并参与PI3K激酶的信号传递(4)。ErbB3高表达于很多癌细胞中（5），而ErbB3/PI3K通路的激活也和许多腺癌的恶性特征相关（6）。在肿瘤发展过程中，ErbB3可能和ErbB家族的其它成员（如，ErbB2需要和ErbB3一起促进乳腺癌细胞的增殖）作为一个原癌基因单位一起发挥功能（7）。因此，抑制ErbB3和ErbB酪氨酸激酶的相互作用已经成为抗癌治疗中的一个新策略

1. Yarden, Y. and Sliwkowski, M.X. (2001) Nat Rev Mol Cell Biol 2, 127-37.
2. Guy, P.M. et al. (1994) Proc Natl Acad Sci U S A 91, 8132-6.
3. Songyang, Z. et al. (1993) Cell 72, 767-78.
4. Kim, H.H. et al. (1994) J Biol Chem 269, 24747-55.
5. Sithanandam, G. et al. (2003) Carcinogenesis 24, 1581-92.
6. Kobayashi, M. et al. (2003) Oncogene 22, 1294-301.
7. Holbro, T. et al. (2003) Proc Natl Acad Sci U S A 100, 8933-8.

原厂资料：

Specificity / Sensitivity

PathScan® Phospho-HER3/ErbB3 (panTyr) Sandwich ELISA Kit #7890 detects endogenous levels of HER3/ErbB3 protein only when phosphorylated at Tyr residues (see Figure 1). The kit sensitivity is shown in Figure 2. This kit does not cross-react with other proteins of ErbB family (data not shown). This kit detects proteins from the indicated species, as determined through in-house testing, but may also detect homologous proteins from other species.

Description

The PathScan® Phospho-HER3/ErbB3 (panTyr) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of tyrosine-phosphorylated HER3/ErbB3 protein. A HER3/ErbB3 mouse antibody has been coated on the microwells. After incubation with cell lysates, HER3/ErbB3 protein (phospho and nonphospho) is captured by the coated antibody. Following extensive washing, a phospho-tyrosine rabbit detection antibody is added to detect captured tyrosine-phosphorylated HER3/ErbB3 protein. Anti-rabbit IgG, HRP-linked antibody is then used to recognize the bound detection antibody. HRP substrate TMB is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of HER3/ErbB3 protein phosphorylated on tyrosine.

Background

HER3/ErbB3 is a member of the ErbB receptor protein tyrosine kinase family, but lacks tyrosine kinase activity. Tyrosine phosphorylation of ErbB3 depends on its association with other ErbB tyrosine kinases. Upon ligand binding, heterodimers form between ErbB3 and other ErbB proteins and ErbB3 is phosphorylated on tyrosine residues by the activated ErbB kinase (1,2). There are at least 9 potential tyrosine phosphorylation sites in the carboxy-terminal tail of ErbB3. These sites serve as consensus binding sites for signal transducing proteins, including Src family members, Grb2, and the p85 subunit of PI3 kinase, which mediate ErbB downstream signaling (3). Both Tyr1222 and Tyr1289 of ErbB3 reside within a YXXM motif and participate in signaling to PI3 kinase (4). 
 ErbB3 is highly expressed in many cancer cells (5) and activation of the ErbB3/PI3K pathway is correlated with malignant phenotypes of adenocarcinomas (6). In tumor development, ErbB3 may function as an oncogenic unit together with other ErbB members (e.g. ErbB2 requires ErbB3 to drive breast tumor cell proliferation) (7). Thus, inhibiting interaction between ErbB3 and ErbB tyrosine kinases has become a novel strategy for anti-tumor therapy.

1. Yarden, Y. and Sliwkowski, M.X. (2001) Nat Rev Mol Cell Biol 2, 127-37.
2. Guy, P.M. et al. (1994) Proc Natl Acad Sci U S A 91, 8132-6.
3. Songyang, Z. et al. (1993) Cell 72, 767-78.
4. Kim, H.H. et al. (1994) J Biol Chem 269, 24747-55.
5. Sithanandam, G. et al. (2003) Carcinogenesis 24, 1581-92.
6. Kobayashi, M. et al. (2003) Oncogene 22, 1294-301.
7. Holbro, T. et al. (2003) Proc Natl Acad Sci U S A 100, 8933-8.

注意事项：

* 12 8-well modules -Each module is designed to break apart for 8 tests.
**Kit should be stored at 4°C with the exception of 10X Cell Lysis Buffer, which is stored at –20°C (packaged separately).