Human HER4 protein (extracellular domain), recombinant

Description :
HER4 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. EGFR signaling is initiated by ligand binding to the extracellular ligand binding domain. This initiates receptor homo-/hetero-dimerization and autophosphorylation by the intracellular kinase domain, resulting in receptor activation. Following activation, 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. HER4 ligands include the neuregulins (NRGs), β-cellulin and heparin-binding EGF-like growth factor (HB-EGF). The ligand binding induces a variety of cellular responses including mitogenesis and differentiation. Multiple proteolytic events allow for the release of a cytoplasmic fragment and an extracellular fragment. Mutations in this gene have been associated with cancer. HER4 and its ligand NRG1 are also implicated in the pathophysiology of schizophrenia.