title: Tyrosine Binding Protein Sites Regulate the Intracellular Trafficking and Processing of Amyloid Precursor Protein through a Novel Lysosome-Directed Pathway.
abstract: The amyloid hypothesis posits that the production of β-amyloid (Aβ) aggregates leads to neurodegeneration and cognitive decline associated with AD. Aβ is produced by sequential cleavage of the amyloid precursor protein (APP) by β- and γ-secretase. While nascent APP is well known to transit to the endosomal/ lysosomal system via the cell surface, we have recently shown that APP can also traffic to lysosomes intracellularly via its interaction with AP-3. Because AP-3 interacts with cargo protein via interaction with tyrosine motifs, we mutated the three tyrosines motif in the cytoplasmic tail of APP. Here, we show that the YTSI motif interacts with AP-3, and phosphorylation of the serine in this motif disrupts the interaction and decreases APP trafficking to lysosomes. Furthermore, we show that phosphorylation at this motif can decrease the production of neurotoxic Aβ 42. This demonstrates that reducing APP trafficking to lysosomes may be a strategy to reduce Aβ 42 in Alzheimer's disease.
authors: J. Allyn Taylor Centre for Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, Western University, London Ontario, Canada, N6A 5B7.|Department of Physiology and Pharmacology, Western University, London, Ontario, Canada, N6A 5B7.
authors: Joshua H K
authors: JH
authors: Tam
authors: Program in Neuroscience, Western University, London, Ontario, Canada, N6A 5B7.
authors: M Rebecca
authors: MR
authors: Cobb
authors: J. Allyn Taylor Centre for Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, Western University, London Ontario, Canada, N6A 5B7.
authors: Claudia
authors: C
authors: Seah
authors: J. Allyn Taylor Centre for Cell Biology, Molecular Medicine Research Group, Robarts Research Institute, Western University, London Ontario, Canada, N6A 5B7.|Department of Physiology and Pharmacology, Western University, London, Ontario, Canada, N6A 5B7.|Program in Neuroscience, Western University, London, Ontario, Canada, N6A 5B7.|Department of Clinical Neurological Sciences, The Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada, N6A 5B7.
authors: Stephen H
authors: SH
authors: Pasternak
mesh_terms: D016564:Amyloid beta-Protein Precursor / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D004705:Endocytosis; D004789:Enzyme Activation; D006801:Humans; D008247:Lysosomes / Q000378:metabolism*; D010766:Phosphorylation; D051744:Protein Kinase C-epsilon / Q000378:metabolism; D021381:Protein Transport; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D016564:Amyloid beta-Protein Precursor; D002352:Carrier Proteins; D014443:Tyrosine; D051744:Protein Kinase C-epsilon