蛋白质CTCF对于脊椎动物绝缘体的增强剂阻断活性是必需的
A C Bell1, A G West, G Felsenfeld
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0540, USA.
Cell
|August 24, 1999
概括
研究人员确定了一种特定的DNA序列,该序列充当绝缘体,阻断基因激活. 这个序列是CTCF蛋白的结合部位,表明脊椎动物的基因调节机制得到保护.
科学领域:
- 分子生物学分子生物学
- 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.
背景情况:
- 绝缘体是DNA序列,阻止调节元件之间的相互作用,如增强剂和促进剂.
- 了解绝缘体的功能对于理解基因调节至关重要.
- 的β-环球蛋白绝缘体是绝缘体元素的一个研究良好的例子.
研究的目的:
- 为了确定负责增强剂阻断活性的最小DNA序列.
- 为了确定与这种绝缘体序列结合的蛋白质因子.
- 研究这一因素在脊椎动物基因调节中的作用.
主要方法:
- 在人类细胞中的42bp子β-环球蛋白绝缘体片段的功能特征.
- 增强器阻断测试以测量绝缘体活动.
- 对DNA与蛋白质的结合研究,以确定结合因子.
主要成果:
- 发现,对于增强剂阻断来说,贝塔-环球蛋白绝缘体的42bp片段是必要的和足够的.
- 这42bp片段是11个指蛋白CTCF的结合部位.
- 在所有检查的脊椎动物增强剂阻断元件中确定了CTCF结合位.
结论:
- 通过特定的DNA结合,CTCF调解了增强剂阻断活性.
- 通过CTCF阻断定向增强剂是脊椎动物基因调节中保存的机制.
- 这一发现提供了对绝缘体在维持基因组组织和控制基因表达模式中的作用的见解.
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