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bioRxiv · 10.1101/150623

Amyloid accumulation drives proteome-wide alterations in mouse models of Alzheimers disease like pathology

Abstract

Amyloid beta (A{beta}) peptides impair multiple cellular pathways in the brain and play a causative role in Alzheimers disease (AD) pathology, but how the brain proteome is remodeled during this process is unknown. To identify new protein networks associated with AD-like pathology, we performed global quantitative proteomic analysis in three mouse models at pre- and post-symptomatic ages. Our analysis revealed a robust and consistent increase in Apolipoprotein E (ApoE) levels in nearly all transgenic brain regions with increased A{beta} levels. Taken together with prior findings on ApoE driving A{beta} accumulation, this analysis points to a pathological dysregulation of the ApoE-A{beta} axis. We also found dysregulation of protein networks involved in excitatory synaptic transmission consistent with AD pathophysiology. Targeted analysis of the AMPA receptor complex revealed a specific loss of TARP{gamma}-2, a key AMPA receptor trafficking protein. Expression of TARP{gamma}-2 in vivo in hAPP transgenic mice led to a restoration of AMPA currents. This database of proteome alterations represents a unique resource for the identification of protein alterations responsible for AD.\n\nHighlightsO_LIProteomic analysis of mouse brains with AD-like pathology reveals stark remodeling\nC_LIO_LIProteomic evidence points to a dysregulation of ApoE levels associated with A{beta} clearance rather than production\nC_LIO_LICo-expression analysis found distinctly impaired synapse and mitochondria modules\nC_LIO_LIIn-depth analyses of AMPAR complex points to loss of TARP{gamma}-2, which may compromise synapses in AD\nC_LI\n\neTOC BlurbProteome-wide profiling of brain tissue from three mouse models of AD-like pathology reveals A{beta}, brain region, and age dependent alterations of protein levels. This resource provides a new global protein expression atlas for the Alzheimers disease research community.

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BibTeXRIS

Savas, J. N., Wang, Y.-Z., DeNardo, L. A., Martinez-Bartolome, S., McClatchy, D. B., Hark, T. J., Shanks, N. F., Cozzolino, K. A., Lavallee-Adam, M., Smukowski, S. N., Park, S. K., Kelly, J. W., Koo, E. H., Nakagawa, T., Masliah, E., Ghosh, A., Yates, J. R.. 2017-06-15. Amyloid accumulation drives proteome-wide alterations in mouse models of Alzheimers disease like pathology. https://doi.org/10.1101/150623

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