ErbB3 Human, sf9
Greater than 90.0% as determined by SDS-PAGE.
Description
ErbB3 is expressed with a 239 amino acid hIgG-His tag at C-Terminus and purified by proprietary chromatographic techniques.
Product Specs
Product Science Overview
Tyrosine Kinase ErbB-3, also known as HER3 (human epidermal growth factor receptor 3), is a member of the ErbB family of receptor tyrosine kinases. This family includes other well-known receptors such as EGFR (ErbB1), HER2 (ErbB2), and ErbB4. ErbB-3 is unique among its family members due to its defective kinase domain, which means it lacks intrinsic kinase activity and relies on dimerization with other ErbB receptors to activate downstream signaling pathways .
ErbB-3 is a type I membrane glycoprotein that consists of an extracellular ligand-binding domain, a single transmembrane helix, and an intracellular domain. The extracellular domain contains four subdomains (I-IV), with subdomains I and III primarily involved in ligand binding, while subdomains II and IV contribute to protein conformation and stability .
Despite its defective kinase domain, ErbB-3 plays a crucial role in cellular signaling. It can form heterodimers with other ErbB family members, particularly ErbB-2 (HER2), to initiate signal transduction. Ligand binding, such as with heregulins (HRG), induces a conformational change in ErbB-3 that allows for dimerization, phosphorylation, and activation of downstream signaling pathways .
ErbB-3 is expressed in various tissues, including keratinocytes, melanocytes, skeletal muscle cells, embryonic myoblasts, and Schwann cells . Its expression is also observed in several types of cancer, where it can contribute to tumor growth and progression. Overexpression of ErbB-3 has been linked to breast cancer, and it is considered a therapeutic target for cancer treatment .
The human recombinant ErbB-3 protein produced in Sf9 Baculovirus cells is a single, glycosylated polypeptide chain containing 863 amino acids. It has a molecular mass of approximately 95.6 kDa and is expressed with a 239 amino acid hIgG-His tag at the C-terminus. This recombinant protein is purified using proprietary chromatographic techniques and is available in various quantities for research purposes .
The recombinant ErbB-3 protein is used in various research applications, including studying its role in cancer, developing therapeutic antibodies, and understanding its signaling mechanisms. It is formulated in a phosphate-buffered saline solution with 10% glycerol and should be stored at 4°C for short-term use or frozen at -20°C for long-term storage .
