详细描述：
The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF-R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF-R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGFa , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGFR homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell
signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF-R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF-R signaling has also been shown to play a role in carcinogenesis.Recombinant human EGF-R produced in CHO cells is a single, glycosylated polypeptide chain of 860 amino acids (25-645 a.a.), having a molecular mass of 95.5 kDa (migrates at 100-150 on SDS-PAGE under reducing conditions). EGF-R is expressed with a 239 amino acid hIgG-His tag at the C-terminus and has been purified by proprietary chromatographic techniques.
