Product Pathways - Tyrosine Kinase / Adaptors

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Phospho-HER3/ErbB3 (Tyr1289) (21D3) Rabbit mAb #4791

Applications	Reactivity	Sensitivity	MW (kDa)	Isotype
W IP IHC-P	H (M) (R) (Dg)	Endogenous	185	Rabbit IgG

Applications Key:  W=Western Blotting  IP=Immunoprecipitation  IHC-P=Immunohistochemistry (Paraffin)
Reactivity Key:  H=Human  M=Mouse  R=Rat  Dg=Dog
Species cross-reactivity is determined by western blot. Species enclosed in parentheses are predicted to react based on 100% sequence homology.

Protocols

4791:

IHC / Paraffin, Immunoprecipitation, Western Blotting

Specificity / Sensitivity

Phospho-HER3/ErbB3 (Tyr1289) (21D3) Rabbit mAb detects endogenous HER3/ErbB3 proteins only when phosphorylated at tyrosine 1289. This antibody may cross-react with overexpressed receptor tyrosine kinases.

Source / Purification

Monoclonal antibody is produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Tyr1289 of human HER3/ErbB3.

Background

HER3/ErbB3 is a member of the ErbB receptor protein tyrosine kinase family, but it 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 PI3K (4).Investigators have found that ErbB3 is highly expressed in many cancer cells (5) and activation of the ErbB3/PI3K pathway is correlated with malignant phenotypes of adenocarcinomas (6). Research studies have demonstrated that 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, investigators view inhibiting interaction between ErbB3 and ErbB tyrosine kinases as a novel strategy for anti-tumor therapy.

1. Yarden, Y. and Sliwkowski, M.X. (2001) Nature Rev. Mol. Cell. Biol. 2, 127-137.
2. Guy, P.M. et al. (1994) Proc. Natl. Acad. Sci. USA 91, 8132-8136.
3. Songyang, Z. et al. (1993) Cell 72, 767-778.
4. Kim, H.H. et al. (1994) J. Biol. Chem. 269, 24747-24755.
5. Sithanandam, G. et al. (2003) Carcinogenesis 24, 1581-1592.
6. Kobayashi, M. et al. (2003) Oncogene 22, 1294-1301.
7. Holbro, T. et al. (2003) Proc. Natl. Acad. Sci. USA 100, 8933-8938.

Application References

• Frogne, T. et al. (2009) Breast Cancer Res 11, R11. Applications: IHC-P (paraffin)
• Sergina, N.V. et al. (2007) Nature 445, 437-41. Applications: Western Blotting
• Weigelt, B. et al. (2010) Breast Cancer Res Treat 122, 35-43. Applications: Western Blotting

Have you published research involving the use of our products? If so we'd love to hear about it. Please let us know!

Companion Products

• 8112 SignalStain^® Antibody Diluent
• 8117 SignalSlide^® Phospho-ErbB Family IHC Controls
• 1180 Phospho-HER3/ErbB3 (Tyr1289) Blocking Peptide
• 4561 Phospho-HER3/ErbB3 (Tyr1197) (C56E4) Rabbit mAb
• 4754 HER3/ErbB3 (1B2E) Rabbit mAb
• 4784 Phospho-HER3/ErbB3 (Tyr1222) (50C2) Rabbit mAb
• 7071 Phototope^®-HRP Western Blot Detection System, Anti-rabbit IgG, HRP-linked Antibody
• 7074 Anti-rabbit IgG, HRP-linked Antibody
• 7720 Prestained Protein Marker, Broad Range (Premixed Format)
• 7727 Biotinylated Protein Ladder Detection Pack
• 7003 20X LumiGLO^® Reagent and 20X Peroxide

Rabbit Monoclonals Produced Using Epitomics® Technology, U.S. Patent No. 5,675,063.

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For Research Use Only. Not For Use In Diagnostic Procedures.