title: Amyloid beta/A4 precursor protein (APP) processing in lysosomes.
abstract: Alzheimer's disease (AD) is characterized by the formation of senile plaques, the main component of which is amyloid beta protein. The processing of the amyloid beta/A4 protein has been implicated in the pathogenesis of AD. We have reported cathepsin B as a candidate APP secretase. By using APP-transfected COS-1 cells, we determined that the putative APP secretase, lysosomal cathepsin B, is involved in the constitutive processing of the precursor molecule. Digestion experiments demonstrated that cathepsin B cleaves the APP molecule into two fragments with molecular masses 115 kDa and 9 kDa, representing presumptive proteolytic fragments of constitutive processing.
authors.affiliation: National Institute of Neuroscience, NCNP, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tagawa
authors.forename: K
authors.initials: K
authors.lastname: Maruyama
authors.forename: S
authors.initials: S
authors.lastname: Ishiura
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism*; D053829:Amyloid Precursor Protein Secretases; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism*; D000818:Animals; D016282:Aspartic Acid Endopeptidases; D002401:Cathepsin B / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism; D006801:Humans; D008247:Lysosomes / Q000378:metabolism*; D011499:Protein Processing, Post-Translational
chemical_list: D016564:Amyloid beta-Protein Precursor; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D002401:Cathepsin B; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human