title: Shedding of the amyloid precursor protein-like protein APLP2 by disintegrin-metalloproteinases.
abstract: Cleavage of the amyloid precursor protein (APP) within the amyloid-beta (Abeta) sequence by the alpha-secretase prevents the formation of toxic Abeta peptides. It has been shown that the disintegrin-metalloproteinases ADAM10 and TACE (ADAM17) act as alpha-secretases and stimulate the generation of a soluble neuroprotective fragment of APP, APPsalpha. Here we demonstrate that the related APP-like protein 2 (APLP2), which has been shown to be essential for development and survival of mice, is also a substrate for both proteinases. Overexpression of either ADAM10 or TACE in HEK293 cells increased the release of neurotrophic soluble APLP2 severalfold. The strongest inhibition of APLP2 shedding in neuroblastoma cells was observed with an ADAM10-preferring inhibitor. Transgenic mice with neuron-specific overexpression of ADAM10 showed significantly increased levels of soluble APLP2 and its C-terminal fragments. To elucidate a possible regulatory mechanism of APLP2 shedding in the neuronal context, we examined retinoic acid-induced differentiation of neuroblastoma cells. Retinoic acid treatment of two neuroblastoma cell lines upregulated the expression of both APLP2 and ADAM10, thus leading to an increased release of soluble APLP2.
authors.affiliation: Institute of Biochemistry, Johannes Gutenberg-University Mainz, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Endres
authors.forename: Rolf
authors.initials: R
authors.lastname: Postina
authors.forename: Anja
authors.initials: A
authors.lastname: Schroeder
authors.forename: Ulrike
authors.initials: U
authors.lastname: Mueller
authors.forename: Falk
authors.initials: F
authors.lastname: Fahrenholz
mesh_terms: D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism; D000072198:ADAM17 Protein; D053829:Amyloid Precursor Protein Secretases; D016564:Amyloid beta-Protein Precursor / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D016282:Aspartic Acid Endopeptidases; D001254:Astrocytoma / Q000188:drug therapy / Q000378:metabolism; D015153:Blotting, Western; D002417:Cattle; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects; D002457:Cell Extracts; D002460:Cell Line; D045744:Cell Line, Tumor; D004151:Dipeptides / Q000494:pharmacology; D019483:Disintegrins / Q000378:metabolism*; D010450:Endopeptidases / Q000235:genetics* / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D045726:Metalloproteases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D016296:Mutagenesis; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009447:Neuroblastoma / Q000188:drug therapy / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology; D012995:Solubility; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014212:Tretinoin / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: C084104:APLP2 protein, human; D016564:Amyloid beta-Protein Precursor; D002457:Cell Extracts; D004151:Dipeptides; D019483:Disintegrins; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; D009419:Nerve Tissue Proteins; D011480:Protease Inhibitors; D014212:Tretinoin; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D045726:Metalloproteases; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human; C509282:Bace1 protein, mouse; D051722:ADAM Proteins; D000072198:ADAM17 Protein; C000606462:ADAM17 protein, human; C000606463:Adam17 protein, mouse; D013755:Tetradecanoylphorbol Acetate