Wang Zi-Xin, Chen Faying, He Bao-Dan, Wang Fan-Chen, Cha Jiaxue, Song Yu, Meng Wei-Ying, Zou Wan-Yue, Fu Yu-Tao, Sun Shu-Xia, Sun Zhi-Yan, Jiang Hao-Ming, Zhao Ke-Yao, Hou Yujun, Shi Jiejun, Xue Jian-Huang
Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education, Tongji Hospital affiliated to Tongji University, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China.
Institute for Regenerative Medicine, State Key Laboratory of Cardiology and Medical Innovation Center, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China.
Adv Sci (Weinh). 2025 Jul 16:e07843. doi: 10.1002/advs.202507843.
Alzheimer's disease (AD) is associated with genetic risk factors and widespread epigenetic alterations. 5-Hydroxymethylcytosine (5hmC), an oxidized derivative of 5-methylcytosine (5mC), constitutes up to 20% of 5mC in neuronal DNA and is implicated in aging and neurodegeneration. However, the precise roles of DNA modifications in AD remain unclear, partly due to the lack of accurate detection methods. Here, two orthogonal sequencing methods are introduced: CMD1-Deaminase sequencing (CD-seq) and CMD1-TET bisulfite sequencing (CT-seq), which enable direct, independent detection of 5mC. When combined with APOBEC-coupled epigenetic sequencing (ACE-seq) or TET-assisted bisulfite sequencing (TAB-seq) for 5hmC mapping, these techniques provide base-resolution, subtraction-free profiling of DNA modifications. Applying them to hippocampal tissue from AD model mice, a significant reduction in 5hmC levels is identified without corresponding changes in 5mC, suggesting that 5hmC functions as an independent epigenetic mark in AD pathogenesis. These findings underscore the importance of precise 5mC/5hmC discrimination and suggest that 5hmC and its regulatory pathways may serve as potential therapeutic targets for AD.
阿尔茨海默病（AD）与遗传风险因素及广泛的表观遗传改变有关。5-羟甲基胞嘧啶（5hmC）是5-甲基胞嘧啶（5mC）的氧化衍生物，在神经元DNA中占5mC的比例高达20%，并与衰老和神经退行性变有关。然而，DNA修饰在AD中的具体作用仍不清楚，部分原因是缺乏准确的检测方法。在此，介绍了两种正交测序方法：CMD1-脱氨酶测序（CD-seq）和CMD1-TET亚硫酸氢盐测序（CT-seq），它们能够直接、独立地检测5mC。当与用于5hmC定位的APOBEC偶联表观遗传测序（ACE-seq）或TET辅助亚硫酸氢盐测序（TAB-seq）相结合时，这些技术可提供碱基分辨率、无减法的DNA修饰图谱。将它们应用于AD模型小鼠的海马组织，发现5hmC水平显著降低，而5mC没有相应变化，这表明5hmC在AD发病机制中作为一个独立的表观遗传标记发挥作用。这些发现强调了精确区分5mC/5hmC的重要性，并表明5hmC及其调控途径可能成为AD的潜在治疗靶点。
