EGFR Human Sf9
Description
Product Specs
The epidermal growth factor receptor (EGFR) subfamily of receptor tyrosine kinases consists of four members: EGFR (also called HER1, ErbB1, or ErbB), ErbB2 (Neu, HER2), ErbB3 (HER3), and ErbB4 (HER4). These type I transmembrane glycoproteins share a structure that includes an extracellular domain with two cysteine-rich domains (responsible for ligand binding) separated by a spacer region, and a cytoplasmic domain containing a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGFR gene encodes a precursor protein of 1210 amino acids (aa), comprising a 24 aa signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGFR binds to several ligands of the EGF family, including EGF, amphiregulin, TGF-alpha, betacellulin, epiregulin, HB-EGF, and neuregulin-2, without requiring a co-receptor. Ligand binding triggers EGFR homodimerization and heterodimerization with ErbB2, leading to kinase activation, tyrosine phosphorylation, and downstream cell signaling. EGFR can also heterodimerize with ligand-activated ErbB3 or ErbB4. EGFR signaling is involved in regulating various biological processes, such as cell proliferation, differentiation, motility, and apoptosis, and plays a role in carcinogenesis.
Product Science Overview
The Epidermal Growth Factor Receptor (EGFR) is a transmembrane protein that plays a crucial role in the regulation of cell growth, survival, proliferation, and differentiation. It is a member of the ErbB family of receptors, which includes four closely related receptors: EGFR (ErbB1), HER2 (ErbB2), HER3 (ErbB3), and HER4 (ErbB4). These receptors are involved in various cellular processes and are significant targets in cancer therapy due to their role in the development and progression of tumors.
EGFR consists of an extracellular ligand-binding domain, a single transmembrane helix, and an intracellular tyrosine kinase domain. Upon binding with its specific ligands, such as epidermal growth factor (EGF) or transforming growth factor-alpha (TGF-α), EGFR undergoes dimerization and autophosphorylation on specific tyrosine residues within the intracellular domain. This activation triggers a cascade of downstream signaling pathways, including the RAS-RAF-MEK-ERK, PI3K-AKT, PLCγ-PKC, and STAT pathways, which regulate various cellular functions .
The recombinant expression of human EGFR in Sf9 cells, a cell line derived from the fall armyworm Spodoptera frugiperda, is a common method used to produce large quantities of the protein for research and therapeutic purposes. Sf9 cells are widely used in the baculovirus expression system due to their high capacity for protein production and proper post-translational modifications.
The purification of recombinant EGFR typically involves several chromatographic techniques to ensure high purity and activity of the protein. Common methods include affinity chromatography, ion-exchange chromatography, and size-exclusion chromatography. The characterization of the purified protein involves assessing its purity, molecular weight, and biological activity through various biochemical and biophysical assays .
Recombinant EGFR is extensively used in research to study its structure, function, and role in disease. It is also a critical component in the development of targeted cancer therapies. Inhibitors of EGFR, such as erlotinib and gefitinib, are used to treat various cancers, including non-small cell lung cancer and colorectal cancer. These inhibitors work by blocking the tyrosine kinase activity of EGFR, thereby preventing the activation of downstream signaling pathways that promote tumor growth and survival .
