Human EGFR protein (extracellular domain), biotinylated, recombinant

Description :
EGFR is known as epidermal growth factor receptor, proto-oncogene c-ErbB-1 , receptor tyrosine-protein kinase erbB-1. It is a member of the epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases (RTK). Four members of the EGFR family have been identified: EGFR (ERBB1, HER1), HER2 (ERBB2), HER3 (ERBB3) and HER4 (ERBB4). They typically contain an extracellular ligand binding domain (ECD), a transmembrane domain (TM), and an intracellular kinase domain that can interact with a multitude of signaling molecules and exhibit both ligand-dependent and ligand-independent activity. The human EGFR has 1210 amino acid (aa), including a 24 aa signal peptide, a 621 aa ECD, and a 23 aa TM segment. It shares 88% aa sequence identity with murine EGFR and 43-44% identity with the ECD of other 3 human EGFR members. EGFR binds to a subset of the EGF family ligands, including EGF, amphiregulin, TGFα, β-cellulin, epiregulin, HB-EGF, and epigen. EGFR signaling is initiated by ligand binding, leading to EGFR receptor homo-/hetero-dimerization and autophosphorylation by the intracellular kinase domain and receptor activation. Subsequently, phosphorylation of cytoplasmic substrates occurs and a signaling cascade is initiated that drives many cellular responses, including changes in gene expression, cytoskeletal rearrangement, anti-apoptosis and increased cell proliferation. EGFR is known to form heterodimers with the ligand-activated HER3 or HER4. EGFR is overexpressed in a variety of tumors. Mutations in EGFR gene are associated with lung cancer. EGFR is the target of several anti-cancer therapeutics.