与普拉德-威利综合征相关的EHMT2-介导基因组印记的机制
Sung Eun Wang1, Yubao Cheng1, Jaechul Lim2,3
1Department of Genetics, Yale University School of Medicine, 333 Cedar St, New Haven, CT 06520, USA.
Research square
|July 16, 2024
概括
普拉德-威利综合征 (PWS) 基因沉默在母亲染色体上是由EHMT2.2维持的. 失去EHMT2将这些PWS基因解除沉默,为印记调节提供了新的见解.
科学领域:
- 遗传学 是一个遗传学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 发展生物学 发展生物学
背景情况:
- 普拉德-威利综合征 (PWS) 源于15q11.2-q13印记域内父性表达基因的丧失.
- 在这个领域的基因印记由双边印记中心 (PWS-IC) 控制,该中心沉默了母亲染色体上的基因.
- 之前的研究表明,EHMT2 (euchromatic histone lysine N-methyltransferase-2) 的抑制剂可以重新激活来自母亲等位基因的沉默PWS基因.
研究的目的:
- 调查EHMT2在PWS 15q11.2-q13域内保持母体印记中的作用.
- 阐明EHMT2调节母亲染色体上基因沉默的分子机制.
- 探索针对PWS的EHMT2的潜在治疗影响.
主要方法:
- 产生和分析缺乏Ehmt2基因的小鼠.
- 检查基因表达,特别是印记的Snrpn/Snhg14基因,在Ehmt2缺陷小鼠的母性染色体.
- 染色体分析,包括3D折叠确认,对患者衍生细胞中的母体PWS-IC进行分析.
- 识别和描述一种与EHMT2.2相互作用的新型非编码RNA.
主要成果:
- 缺少EHMT2导致小鼠大脑中的母性染色体上印记的Snrpn/Snhg14基因的非沉默.
- 发现母体PWS-IC中的染色体在PWS和安吉尔曼综合征患者细胞中是封闭的和紧的.
- 一种新的非编码RNA被确定,它与EHMT2相互作用,形成异染色素复合体,沉默SNRPN基因表达在母体染色体上.
结论:
- 对EHMT2的基因特异性招募对于在PWS域中保持母性印记至关重要.
- 一种新型的非编码RNA和EHMT2形成了一个使母体PWS基因沉默的复合体.
- 这些发现提出了在PWS印记域内印记维护的新模型,并突出了EHMT2的关键作用.
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