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bioRxiv · 10.1101/2024.10.25.620263

Human-mouse proteomics reveals the shared pathways in Alzheimer's disease and delayed protein turnover in the amyloidome

Abstract

Murine models of Alzheimers disease (AD) are crucial for elucidating disease mechanisms but have limitations in fully representing AD molecular complexities. We comprehensively profiled age-dependent brain proteome and phosphoproteome (n > 10,000 for both) across multiple mouse models of amyloidosis. We identified shared pathways by integrating with human metadata, and prioritized novel components by multi-omics analysis. Collectively, two commonly used models (5xFAD and APP-KI) replicate 30% of the human protein alterations; additional genetic incorporation of tau and splicing pathologies increases this similarity to 42%. We dissected the proteome-transcriptome inconsistency in AD and 5xFAD mouse brains, revealing that inconsistent proteins are enriched within amyloid plaque microenvironment (amyloidome). Determining the 5xFAD proteome turnover demonstrates that amyloid formation delays the degradation of amyloidome components, including A{beta}-binding proteins and autophagy/lysosomal proteins. Our proteomic strategy defines shared AD pathways, identify potential new targets, and underscores that protein turnover contributes to proteome-transcriptome discrepancies during AD progression.

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BibTeXRIS

Yarbro, J. M., Han, X., Dasgupta, A., Yang, K., Liu, D., Shrestha, H., Zaman, M., Wang, Z., Yu, K., Lee, D. G., Vanderwall, D., Niu, M., Sun, H., Xie, B., Chen, P.-C., Jiao, Y., Zhang, X., Wu, Z., Fu, Y., Li, Y., Yuan, Z.-F., Wang, X., Poudel, S., Vagnerova, B., He, Q., Tang, A., Ronaldson, P., Chang, R., YU, G., Liu, Y., Peng, J.. 2024-10-25. Human-mouse proteomics reveals the shared pathways in Alzheimer's disease and delayed protein turnover in the amyloidome. https://doi.org/10.1101/2024.10.25.620263

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