title: Ectodomain cleavage of ErbB-4: characterization of the cleavage site and m80 fragment.
abstract: Ectodomain cleavage of the ErbB-4 receptor tyrosine kinase generates a membrane-associated fragment of 80 kDa (m80) that has been subjected to N-terminal sequencing. The sequence obtained shows that the N terminus of this fragment begins with Ser-652 of ErbB-4. When a 12-residue peptide corresponding to ErbB-4 residues 646-657 was incubated with recombinant tumor necrosis factor-alpha-converting enzyme, fragments representing residues 646-651 and 652-657 were obtained. These data indicate that ectodomain cleavage of ErbB-4 occurs between His-651 and Ser-652, placing the cleavage site within the ectodomain stalk region approximately 8 residues prior to the transmembrane domain. Several experiments have characterized other aspects of the m80 ErbB-4 fragment. Inhibition of ErbB-4 tyrosine kinase activity with pan-ErbB tyrosine kinase inhibitors indicates that kinase activity is stringently required for heregulin-dependent, but not 12-O-tetradecanoylphorbol-13-acetate-induced, ErbB-4 ectodomain cleavage and formation of the m80 fragment. When the m80 ErbB-4 fragment is generated by cell treatment with heregulin or 12-O-tetradecanoylphorbol-13-acetate, the fragment associates with intact ErbB-2. However, this fragment does not associate with the intact ErbB-4 molecule.
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA.
authors.forename: Qiu-Chen
authors.initials: QC
authors.lastname: Cheng
authors.forename: Oleg
authors.initials: O
authors.lastname: Tikhomirov
authors.forename: Wenli
authors.initials: W
authors.lastname: Zhou
authors.forename: Graham
authors.initials: G
authors.lastname: Carpenter
mesh_terms: D051722:ADAM Proteins; D000072198:ADAM17 Protein; D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D003902:Detergents / Q000494:pharmacology; D066246:ErbB Receptors / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D008666:Metalloendopeptidases / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D066247:Receptor, ErbB-4; D011994:Recombinant Proteins / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D003902:Detergents; D010455:Peptides; D011994:Recombinant Proteins; D012694:Serine; C587689:ERBB4 protein, human; D066246:ErbB Receptors; C587690:Erbb4 protein, mouse; D066247:Receptor, ErbB-4; D051722:ADAM Proteins; D008666:Metalloendopeptidases; D000072198:ADAM17 Protein; D013755:Tetradecanoylphorbol Acetate