Cell Signaling Technology

Product Pathways - Tyrosine Kinase/ Adaptors

Phospho-EGF Receptor (Tyr845) Blocking Peptide #1100

Description

This peptide is used to block Phospho-EGF Receptor (Tyr845) Antibody #2231 reactivity.

Quality Control

The quality of the peptide was evaluated by reversed-phase HPLC and by mass spectrometry. The peptide blocks Phospho-EGF Receptor (Tyr845) Antibody #2231 signal completely in Western blotting.

Western Blotting

Western Blotting

Western blot analysis of extracts from A431 cells, untreated or EGF-stimulated, using Phospho-EGF Receptor (Tyr845) Antibody (left) or the same antibody preincubated with Phospho-EGF Receptor (Tyr845) Antibody Blocking Peptide (right).

Applications

Use as a blocking reagent to evaluate the specificity of antibody reactivity in Western Blot protocols.

Directions for Use

For Western immunoblotting, add 10 µl of antibody and 10 µl of blocking peptide to 10 ml of antibody dilution buffer, and incubate at room

temperature for 30 minutes before allowing to react with the blot.

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