Abstract
Background
Epigenetic mechanisms, particularly histone modifications at gene promoters, are crucial for controlling gene transcription.
Objective
We aim to find out epigenomic aberrations during the progression of neurodegenerative disorders.
Methods
We employed a multifaceted approach to investigate how the two key histone methylation marks, H3K4me3 (linked to gene activation) and H3K27me3 (linked to gene suppression), are altered in postmortem prefrontal cortex of humans with mild cognitive impairment (MCI) or Alzheimer's disease (AD).
Results
Compared to controls, MCI and AD exhibited pronounced losses of permissive H3K4me3 peaks at promoters of genes enriched in synaptic plasticity and neurotransmission, and significant gains of H3K4me3 peaks at promoters of genes enriched in transcriptional regulation. AD displayed more substantial H3K4me3 losses on synaptic genes than MCI. Conversely, significant gains of repressive H3K27me3 peaks were observed at synaptic gene promoters in both disease groups, with MCI exhibiting more pronounced H3K27me3 gains on synaptic genes than AD. Weighted Gene Correlation Network Analysis (WGCNA) revealed multiple modules characterizing distinct patterns of gains and losses of H3K4me3 and H3K27me3 during the transition from MCI to AD. Integrative analysis of epigenomic and transcriptomic data indicated that these histone mark alterations were well correlated with the downregulation of synaptic genes and upregulation of transcriptional regulators in AD.
Conclusions
This comprehensive profiling uncovers a stage-dependent reorganization of histone modifications at critical gene loci, implicating these events in the molecular cascade of AD pathogenesis. Targeting dysregulated chromatin states may offer novel therapeutic avenues for early intervention of AD.
Keywords
Get full access to this article
View all access options for this article.
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
