title: Role of the ErbB-4 carboxyl terminus in gamma-secretase cleavage.
abstract: The ErbB-4 receptor tyrosine kinase has a PDZ domain recognition motif at its carboxyl terminus. The first step in ErbB-4 proteolytic processing is a metalloprotease-dependent cleavage of the receptor ectodomain, which is not influenced by deletion of this motif. Metalloprotease cleavage of ErbB-4 produces a membrane-associated 80-kDa fragment that is a substrate for subsequent gamma-secretase cleavage, which releases the cytoplasmic domain from the membrane and allows nuclear translocation of this fragment. Deletion of the PDZ domain recognition motif does abrogate the gamma-secretase cleavage of ErbB-4. The wild-type 80-kDa ErbB-4 fragment forms an association complex with presenilin, thought to be the catalytic moiety of gamma-secretase activity. However, this association is significantly impaired by loss of the PDZ domain recognition motif from ErbB-4. Deletion of this ErbB-4 motif prevents the nuclear localization of the ErbB-4 cytoplasmic domain. Data also show that the basal cleavage of wild-type ErbB-4 by this proteolytic system can produce a sufficient level of ErbB-4 processing to negatively influence cell growth and that loss of the PDZ domain recognition motif abrogates this response.
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA.
authors.forename: Chang-Yuan
authors.initials: CY
authors.lastname: Ni
authors.forename: Hongping
authors.initials: H
authors.lastname: Yuan
authors.forename: Graham
authors.initials: G
authors.lastname: Carpenter
mesh_terms: D016475:3T3 Cells; D053829:Amyloid Precursor Protein Secretases; D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000378:metabolism; D019556:COS Cells; D020134:Catalytic Domain; D002455:Cell Division; D010450:Endopeptidases / Q000378:metabolism*; D066246:ErbB Receptors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D066247:Receptor, ErbB-4; D017384:Sequence Deletion
chemical_list: C587689:ERBB4 protein, human; D066246:ErbB Receptors; C587690:Erbb4 protein, mouse; D066247:Receptor, ErbB-4; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human; C509282:Bace1 protein, mouse