| ErbB2 proto-oncogene encodes a transmembrane receptor-like glycoprotein of 185kD with intrinsic tyrosine kinase activity. ErbB2 does not have any known ligand with high affinity binding. However, the kinase activity of ErbB2 can be activated without any ligand when overexpressed or by heteroassociation with other members of the ErbB family (1). Amplification of the ErbB2 gene and overexpression of its product was detected in almost 40% of human breast cancers (2). ErbB2 is one of the major drug targets for breast cancer and other cancer treatments. The distinct tyrosine phosphorylation sites play an important role in modulation of ErbB2 mediated function. Tyrosine 877 of ErbB2 is homologous to pp60c-Src Tyr416 located in the kinase domain. Phosphorylation of this site may be involved in regulation of ErbB2 biological activity. Tyrosine 1112 of ErbB2 is a binding site for c-Cbl ubiquitin ligase. Binding of c-Cbl to ErbB2 results in poly-ubiquitination of ErbB2 and enhances its degradation (3,4). Tyrosine1248 of ErbB2 is one of the major autophosphorylation sites in this molecule. The phosphorylation of this site couples ErbB2 to the Ras-Raf-MAP kinase signaling transduction pathway (5). The Phospho-HER2/ErbB2 Antibody Sampler Kit provides an economical means to evaluate the activation status of HER2/ErbB2, including the phosphorylation of Tyr877 and Tyr1248. The control HER2/ErbB2 antibody is also included. The kit contains enough primary and secondary antibodies to perform four mini-blot experiments. Kit Components: E3451-28A HER2/ErbB2, phosphorylated (Tyr877) Pab 1x20ul Purified by protein A and peptide affinity chromatography. Supplied as liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, BSA, 50% glycerol. Suitable for use in Western Blot. E3451-28B HER2/ErbB2, phosphorylated (Tyr1221/1222) Pab 1x20ul Purified by protein A and peptide affinity chromatography. Supplied as liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, BSA, 50% glycerol. Suitable for use in Western Blot and Immunohistochemistry (frozen and paraffin). E3451-28C HER2/ErbB2 Pab 1x20ul Purified by protein A and peptide affinity chromatography. Supplied as liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, BSA, 50% glycerol. Suitable for use in Western Blot, Immunoprecipitation, Immunohistochemistry (frozen and paraffin), Immunocytochemistry/Immunofuorescence, and Flow Cytometry. E3451-28D IgG (HRP) 1x100ul. Supplied as liquid in 10mM sodium HEPES, pH 7.5, 150mM sodium chloride, BSA, 50% glycerol. Specificity/Sensitivity: All antibodies in this kit detect endogenous levels of their targeted tyrosine-phosphorylated ErbB2 proteins. E3451-28A and E3451-28B recognize only the phosphorylated form of HER2/ErbB2 at the indicated sites. The control E3451-28C HER2/ErbB2 receptor antibody recognizes both phosphorylated and nonphosphorylated forms of HER2/ErbB2. Species Cross-reactivity: E3451-28A HER2/ErbB2, phosphorylated (Tyr877) and E3451-28C HER2/ErbB2 antibodies react with human and are predicted to cross-react with mouse and rat species based on 100% immunogen sequence homology. E3451-28B HER2/ErbB2, phosphorylated (Tyr1221/1222) rabbit monoclonal antibody is human specific. Storage and Stability: For long-term storage, aliquot and store at -20C. Aliquots are stable for at least 6 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer. |
