ERBB3 [SEP] found in taxon
ERBB3
Receptor tyrosine-protein kinase erbB-3, also known as HER3 (human epidermal growth factor receptor 3), is a membrane bound protein that in humans is encoded by the ERBB3 gene.
ErbB3 is a member of the epidermal growth factor receptor (EGFR/ERBB) family of receptor tyrosine kinases. The kinase-impaired ErbB3 is known to form active heterodimers with other members of the ErbB family, most notably the ligand binding-impaired ErbB2.
Gene and expression.
The human "ERBB3" gene is
-functional because the kinase-impaired protein requires transphosphorylation by its binding partner to be active.
Unlike the other ErbB receptor tyrosine kinase family members which are activated through autophosphorylation upon ligand binding, ErbB3 was found to be kinase impaired, having only 1/1000 the autophosphorylation activity of EGFR and no ability to phosphorylate other proteins. Therefore, ErbB3 must act as an allosteric activator.
Function Interaction with ErbB2.
The ErbB2-ErbB3 dimer is considered the most active of the possible ErbB dimers, in part because ErbB2 is the preferred dimerization partner