免疫球蛋白mu基因活跃转录状态的稳定传播需要持续增强功能增强剂
1Department of Microbiology and Immunology, University of California, San Francisco 94143.
Cell
|November 18, 1988
概括
免疫球蛋白重链基因表达需要增强剂来进行初始激活和持续转录. 删除增强剂会关闭基因表达,表明它缺乏记忆功能.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 基因规则 基因规则
背景情况:
- 增强剂序列是控制基因表达的关键调节元素.
- 免疫球蛋白Mu重链基因的表达是由增强剂调节的.
- 了解如何在细胞分裂中维持转录状态至关重要.
研究的目的:
- 研究是否增强剂元素赋予免疫球蛋白重链基因转录活性的"记忆".
- 为了确定mu基因的活跃转录状态是否可以在增强体被删除后在子细胞中保持.
- 评估增强剂在基因表达的建立和维持中的作用.
主要方法:
- 一个含有增强剂的修饰mu基因稳定引入到前B细胞中.
- 诱导D-to-J重组以删除增强剂序列.
- 在增强剂删除之前和之后监测mu基因转录.
- 分析mu基因的DNA甲基化状态.
主要成果:
- 在稳定引入到前B细胞时,Mu基因转录被启动.
- 通过D-to-J连接的增强剂的后续删除可重复性地沉默了mu基因表达.
- 尽管基因在增强剂删除之前被低甲基化,但发生了转录失活.
- 增强剂是维持mu基因表达所必需的.
结论:
- 增强剂元素不会赋予免疫球蛋白重链基因转录活性的"记忆".
- 增强剂对于基因表达的初始建立和持续维护都至关重要.
- 转录沉默发生在增强器删除时,无论DNA甲基化状态如何.
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