Cell Signaling Technology

Product Pathways - Tyrosine Kinase/ Adaptors

Phospho-EGF Receptor (Tyr1148) Antibody #4404

Applications Reactivity Sensitivity MW (kDa) Source
W IHC-P H Mk Endogenous 175 Rabbit

Applications Key:  W=Western Blotting  IHC-P=Immunohistochemistry (Paraffin)
Reactivity Key:  H=Human  Mk=Monkey
Species enclosed in parentheses are predicted to react based on 100% sequence homology. Species cross-reactivity is determined by Western blot.

Specificity / Sensitivity

Phospho-EGF Receptor (Tyr1148) Antibody detects endogenous levels of EGF receptor only when phosphorylated at tyrosine 1148. This antibody does not cross-react with other tyrosine-phosphorylated ErbB family members.

Source / Purification

Polyclonal antibodies are produced by immunizing rabbits with a synthetic phospho-peptide (KLH-coupled) corresponding to residues surrounding Tyr1148 of human EGF receptor. Antibodies are purified by protein A and peptide affinity chromatography.

Western Blotting

Western Blotting

Western blot analysis of extracts from A431 cells, untreated or EGF-stimulated, using Phospho-EGF Receptor (Tyr1148) Antibody (upper) or EGF Receptor Antibody #2232 (lower).

Western Blotting

Western Blotting

Western blot analysis of various cell lysates containing activated EGFR, ErbB2, ErbB3 and ErbB4 proteins, using Phospho-EGF Receptor (Tyr1148) Antibody (upper) or Phospho-Tyrosine mAb (P-Tyr-100) #9411 (lower).

IHC-P (paraffin)

IHC-P (paraffin)

Immunohistochemical staining of phosphorylated EGF Receptor in paraffin-embedded human breast carcinoma, showing membrane localization using Phospho-EGF Receptor (Tyr1148) Antibody.


IHC-P (paraffin)

IHC-P (paraffin)

Immunohistochemical analysis of paraffin-embedded MDA-MB-468 cells, untreated (left), EGF-treated (middle) or EGF and Tarceva ®- treated (right), using Phospho-EGF Receptor (Tyr1148) Antibody.

Background

The epidermal growth factor (EGF) receptor is a 170 kDa transmembrane tyrosine kinase that belongs to the HER/ErbB protein family. Ligand binding results in receptor dimerization, autophosphorylation, activation of downstream signaling and lysosomal degradation (1,2). Phosphorylation of EGF receptor (EGFR) at Tyr845 in the kinase domain is implicated in stabilizing the activation loop, maintaining the active state enzyme and providing a binding surface for substrate proteins (3,4). c-Src is involved in phosphorylation of EGFR at Tyr845 (5). The SH2 domain of PLCγ binds at phospho-Tyr992, resulting in activation of PLCγ-mediated downstream signaling (6). Phosphorylation of EGFR at Tyr1045 creates a major docking site for c-Cbl, an adaptor protein that leads to receptor ubiquitination and degradation following EGFR activation (7,8). The GRB2 adaptor protein binds activated EGFR at phospho-Tyr1068 (9). A pair of phosphorylated residues (Tyr1148 and Tyr1173) provides a docking site for the SHC scaffold protein, with both sites involved in MAP kinase signaling activation (2). Phosphorylation of EGFR at specific serine and threonine residues attenuates EGFR kinase activity. EGFR carboxy-terminal residues Ser1046 and Ser1047 are phosphorylated by CaM kinase II; mutations to either of these serines results in upregulated EGFR tyrosine autophosphorylation (10).

  1. Hackel, P.O. et al. (1999) Curr. Opin. Cell Biol. 11, 184-189.
  2. Zwick, E. et al. (1999) Trends Pharmacol. Sci. 20, 408-412.
  3. Cooper, J.A. and Howell, B. (1993) Cell 73, 1051-1054.
  4. Hubbard, S.R. et al. (1994) Nature 372, 746-754.
  5. Biscardi, J.S. et al. (1999) J. Biol. Chem. 274, 8335-8343.
  6. Emlet, D.R. et al. (1997) J. Biol. Chem. 272, 4079-4086.
  7. Levkowitz, G. et al. (1999) Mol. Cell 4, 1029-1040.
  8. Ettenberg, S.A. et al. (1999) Oncogene 18, 1855-1866.
  9. Rojas, M. et al. (1996) J. Biol. Chem. 271, 27456-27461.
  10. Feinmesser, R.L. et al. (1999) J. Biol. Chem. 274, 16168-16173.

Application References

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

This product is for in vitro research use only and is not intended for use in humans or animals. This product is not intended for use as therapeutic or in diagnostic procedures.

Product Pathways

Drug Discovery Tools

Featured Technologies

Protein Classes