Studies will test the hypothesis that beta-amyloid precursor protein (APP) normally functions as a signal-transducing cell surface receptor and pathological functions of APP in Alzheimer's disease reflect perturbations of that receptor function. It is proposed that APP resembles the receptor Notch in possessing two alternative signaling pathways - one propagated from the membrane-resident receptor and another propagated by nuclear translocation of the cytoplasmic domain of the receptor following gamma-secretase cleavage within the membrane-spanning sequence of the protein. Studies will employ various cell lines including COS7 cells, a neon-neuronal cell line, and NGF-differentiated PC12 cells, a neuronal cell line. Transient and stable transfection will be employed to manipulate expression of APP and proteins with which it interacts. Green fluorescent protein (GFP) and myc epitope tags will be employed to follow intracellular trafficking of beta-amyloid precursor protein following transfection. APP-GaI4/VP1 6 and APP-GaI4 fusion proteins will be expressed in reporter cell lines that express luciferase under control of a Gal4 promoter, providing a quantitative means of assessing the nuclear translocation of the APP cytoplasmic domain, and providing an assay for APP mutations and pharmacological manipulations that promote or inhibit nuclear access of the cytoplasmic domain. Mutations will be targeted to a CDK5 phosphorylation site, to a putative nuclear localization signal, to a putative PEST motif, to a Dab1/Fe65 binding site, and to putative ubiquitinization sites, and the effects on subcellular localization and nuclear translocation will be assessed. Effects of agonistic APP monoclonal antibody, beta-amyloid peptide, LRP, and alpha-2 macroglobulin on APP signaling will be assessed.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
5R01AG021127-05
Application #
7118087
Study Section
Special Emphasis Panel (ZRG1-MDCN-2 (01))
Program Officer
Snyder, Stephen D
Project Start
2002-09-15
Project End
2008-08-31
Budget Start
2006-09-01
Budget End
2008-08-31
Support Year
5
Fiscal Year
2006
Total Cost
$351,589
Indirect Cost
Name
University of Washington
Department
Physiology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
de Laat, Rian; Meabon, James S; Wiley, Jesse C et al. (2015) LINGO-1 promotes lysosomal degradation of amyloid-? protein precursor. Pathobiol Aging Age Relat Dis 5:25796
Wiley, Jesse C; Smith, Elise A; Hudson, Mark P et al. (2007) Fe65 stimulates proteolytic liberation of the beta-amyloid precursor protein intracellular domain. J Biol Chem 282:33313-25
Wiley, Jesse C; Hudson, Mark; Kanning, Kevin C et al. (2005) Familial Alzheimer's disease mutations inhibit gamma-secretase-mediated liberation of beta-amyloid precursor protein carboxy-terminal fragment. J Neurochem 94:1189-201