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bioRxiv · 10.1101/273789

Epigenome-wide study uncovers tau pathology-driven changes of chromatin organization in the aging human brain

Abstract

Accumulation of tau and amyloid-{beta} are two pathologic hallmarks of Alzheimers disease (AD). Here, we conducted an epigenome-wide association study using the H3K9 acetylation (H3K9Ac) mark in 669 aged human prefrontal cortices: in contrast to amyloid-{beta}, tau protein burden had a broad effect on the epigenome, affecting 5,590 out of 26,384 H3K9Ac domains. Tau-related alterations aggregated in large genomic segments reflecting spatial chromatin organization, and the magnitude of these effects correlated with the segments nuclear lamina association. We confirmed the functional relevance of these chromatin changes by demonstrating (1) consistent transcriptional changes in three independent datasets and (2) similar findings in two AD mouse models. Finally, we found that tau overexpression in iPSC-derived neurons disrupted chromatin organization and that these effects could be blocked by a small molecule predicted to reverse the tau effect. Thus, we report large-scale tau-driven chromatin rearrangements in the aging human brain that may be reversible with HSP90 inhibitors.

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Klein, H.-U., McCabe, C., Gjoneska, E., Sullivan, S. E., Kaskow, B. J., Tang, A., Smith, R. V., Xu, J., Pfenning, A. R., Bernstein, B. E., Meissner, A., Schneider, J. A., Mostafavi, S., Tsai, L.-H., Young-Pearse, T. L., Bennett, D. A., De Jager, P. L.. 2018-02-28. Epigenome-wide study uncovers tau pathology-driven changes of chromatin organization in the aging human brain. https://doi.org/10.1101/273789

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