EGFR Human Sf9, Active

The Epidermal Growth Factor Receptor (EGFR) is a critical component in the regulation of cell growth, survival, proliferation, and differentiation. It is a member of the ErbB family of receptor tyrosine kinases, which includes four closely related receptors: EGFR (ErbB1), ErbB2 (HER2/neu), ErbB3 (HER3), and ErbB4 (HER4) . These receptors are involved in various cellular processes and have significant implications in cancer biology when their expression or activity is dysregulated .

EGFR is a transmembrane glycoprotein with an extracellular ligand-binding domain, a single hydrophobic transmembrane segment, and an intracellular tyrosine kinase domain . The receptor is activated upon binding to specific ligands such as epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), and others . Ligand binding induces receptor dimerization, either as homodimers or heterodimers with other ErbB family members, leading to autophosphorylation of tyrosine residues in the cytoplasmic domain . This autophosphorylation triggers a cascade of downstream signaling pathways, including the MAPK, PI3K/AKT, and JAK/STAT pathways, which regulate various cellular responses .

The recombinant expression of human EGFR in Sf9 cells (a cell line derived from the fall armyworm Spodoptera frugiperda) is a common method for producing active EGFR protein for research purposes . The baculovirus expression system used in Sf9 cells allows for high-level expression of recombinant proteins with proper post-translational modifications, which are essential for the biological activity of EGFR . The recombinant EGFR expressed in Sf9 cells is often fused with tags such as GST (Glutathione S-transferase) to facilitate purification and detection .

Recombinant EGFR is widely used in biochemical and structural studies to understand its function and regulation. It is also employed in drug discovery and development, particularly in screening for inhibitors that can block EGFR signaling in cancer cells . The availability of active recombinant EGFR enables researchers to study the receptor’s interactions with ligands, other proteins, and small-molecule inhibitors in a controlled environment .