Heregulin induces tyrosine phosphorylation of HER4/p180erbB4.

来自 EBSCO

阅读量：

作者：

Plowman，Gregory，d.，Green，Janell，M.，Culouscou，Jean-Michel，Carlton，Gary

展开

摘要：

THE HER4/ERBB4 gene encodes a 180K transmembrane protein(HER4/pl80 erbB4 that is structurally related to the 185Kproduct (HERl/pl85 erbB2 of the HER2/ERBB2 proto-oncogene 1 . A 45K heparin-binding glycoprotein (p45) hasbeen characterized that specifically activates the intrinsic tyrosine kinaseactivity of HER4 (ref. 2). This HER4 ligand shares several features with theheregulin family of proteins, including molecular mass, ability to inducedifferentiation of breast cancer cells, activation of tyrosine phosphorylationin MDA-MB453 cells and amino-terminal protein sequence. Heregulin exists asmultiple isoforms and all are presumed to interact directly with HER2 (refs3–6). We have used binding and phosphorylation studies with recombinant ligandon cell lines expressing recombinant receptors and report here that heregulin,like p45, is a specific ligand for HER4. Furthermore, heregulin fails to inducephosphorylation of HER2 in the absence of HER4. These findings suggest thatactivation of the HER4 receptor is involved in signal transduction byheregulin.

展开

关键词：

Animals Humans Cell Line CHO Cells Tyrosine Receptor, Epidermal Growth Factor Receptor, erbB-2 Glycoproteins Neuregulins Recombinant Proteins