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Amyloid beta/A4 precursor protein (APP) processing in lysosomes.

K Tagawa·K Maruyama·S Ishiura
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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.

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Alzheimer DiseaseAmyloid Precursor Protein SecretasesAmyloid beta-Protein PrecursorAnimalsAspartic Acid EndopeptidasesCathepsin BEndopeptidasesHumansLysosomesProtein Processing, Post-TranslationalJournal ArticleResearch Support, Non-U.S. Gov'tReview

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BibTeXRIS

K Tagawa, K Maruyama, S Ishiura. 1992-12-31. Amyloid beta/A4 precursor protein (APP) processing in lysosomes.. https://doi.org/10.1111/j.1749-6632.1992.tb27482.x

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