Description
This gene encodes a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases. This protein has no ligand binding domain of its own and therefore cannot bind growth factors. However, it does bind tightly to other ligand-bound EGF receptor family members to form a heterodimer, stabilizing ligand binding and enhancing kinase-mediated activation of downstream signalling pathways, such as those involving mitogen-activated protein kinase and phosphatidylinositol-3 kinase. Allelic variations at amino acid positions 654 and 655 of isoform a (positions 624 and 625 of isoform b) have been reported, with the most common allele, Ile654/Ile655, shown here. Amplification and/or overexpression of this gene has been reported in numerous cancers, including breast and ovarian tumors. Alternative splicing results in several additional transcript variants, some encoding different isoforms and others that have not been fully characterized.
Molecular Mass
Predicted Molecular Mass: 96.8 kDa (monomer)
SDS-PAGE: 125-130 kDa, reducing conditions, 220-250 kDa, non-reducing conditions
Bio-activity
Measured by its ability to block anti-ErbB2 mediated inhibition of SK-BR-3 human breast cancer cell proliferation. Brodowicz, T. et al. (1997) Int. J. Cancer 73:875. The ED50 for this effect is 0.3-1.2 μg/mL in the presence of 0.6 μg/mL Anti-Human ErbB2/Her2 Monoclonal Antibody.
Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 centigrade as supplied.
1 month, 2 to 8 centigrade under sterile conditions after reconstitution.
3 months, -20 to -70 centigrade under sterile conditions after reconstitution.
