Epidermal Growth Factor Receptor (erbB, EGFR)

The epidermal growth factor (EGF) receptor is a 170 kD 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 PLCg binds at phospho-Tyr992, resulting In activation of PLCg-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 autokinase activity (10). Applications: Suitable for use in Western Blot and Immunoprecipitation. Other applications not tested. Recommended Dilution: Western Blot: 1:1000 Immunoprecipitation: 1:50 Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4 degrees C for short-term only. For long-term storage, aliquot and store at -20 degrees C. Aliquots are stable for at least 12 months at -20 degrees C. 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.