衰老促进巴尔体在距离染色体区域的重新激活
Sarah Hoelzl1,2, Tim P Hasenbein1,2, Stefan Engelhardt1,2
1Institute of Pharmacology and Toxicology, Technical University Munich, Munich, Germany.
Nature aging
|May 1, 2025
概括
雌性小鼠显示,随着衰老,从不活跃的X染色体 (巴尔体) 中脱离基因的增加. 这种与年龄相关的基因在整个组织中的重新激活可能会导致老年女性的性别偏差疾病进展.
科学领域:
- 遗传学 遗传学 是一个
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 衰老研究研究 衰老研究
背景情况:
- 不活跃的X染色体 (巴尔体) 对于性别之间的基因剂量补偿至关重要.
- 巴尔体的稳定沉默是至关重要的,但在老化过程中其维护并未得到充分理解.
- 以前对小鼠的研究表明,不活跃的X染色体上单个基因的与年龄相关的重新激活.
研究的目的:
- 在老鼠发育和衰老过程中,全面对逃脱X染色体不活化的基因进行分类.
- 为了调查是否在不活跃的X染色体上基因沉默在整个衰老过程中保持.
- 探索衰老对X染色体失活逃脱率的影响及其与年龄相关疾病的潜在联系.
主要方法:
- 采用了基因特异性多组学方法来进行全面的基因目录.
- 在发育和衰老期间,分析了各种器官和细胞类型的X染色体失活逃脱率.
- 评估了老年小鼠在遥远染色体区域的染色质可访问性变化.
主要成果:
- 在多个器官中观察到在衰老期间从不活跃的X染色体中大幅增加基因逃逸率.
- 确定与年龄相关的X染色体失活逃脱发生在各种细胞类型中.
- 在染色体末端的超大基中发现染色体可访问性增加,影响逃生基因的调节元件.
- 在距离染色体区域集中了较高的逃逸率.
结论:
- 衰老导致雌性小鼠中不活跃的X染色体上基因的广泛重新激活.
- 在染色体末端增加的染色质可访问性与特定年龄的基因逃逸有关.
- 特定于年龄的脱离基因的高表达,其中一些与人类疾病有关,可能会导致老年女性的性别偏差疾病进展.
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