Abstract
The accumulation of the amyloid-β (Aβ) peptide in the form of insoluble fibrillar deposits and soluble oligomeric aggregates is widely believed to play a causal role in Alzheimer’s disease (AD). Proteolytic cleavage of APP by the β-site APP cleaving enzyme (BACE1) near the C-terminus results in the formation of the APP C-terminal fragment (CTF) C99, a substrate for subsequent cleavage by γ-secretase to generate Aβ. Alternatively, APP cleavage by α-secretase to generate the APP CTF C83 occurs within the Aβ region, precluding its formation. Therefore, modulation of β- and/or γ-secretase activity represents important therapeutic targets. Transgenic mice overexpressing human APP generate detectable levels of APP CTFs and Aβ. We have shown that highly sensitive and specific methods for determining levels of APP CTFs and Aβ are useful for understanding how genetic manipulation of APP processing impacts Aβ generation and accumulation.
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Acknowledgments
The author would like to thank Dr. Ron DeMattos for the development of the acetic acid urea PAGE protocol and for his advice on the use of the technique, Dr. Eliezer Masliah for providing the opportunity to collaborate on the hAPP/BACE1 project, Dr. Lennart Mucke for his mentorship, advice, and encouragement, and Dr. Judy Cam for reviewing the manuscript.
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Esposito, L.A. (2010). Measuring APP Carboxy-Terminal Fragments. In: Roberson, E. (eds) Alzheimer's Disease and Frontotemporal Dementia. Methods in Molecular Biology, vol 670. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-60761-744-0_6
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DOI: https://doi.org/10.1007/978-1-60761-744-0_6
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