序列特异性转录因子NF-Y表现出类似希斯顿的DNA结合和类似H2B的无处不在
Marco Nardini1, Nerina Gnesutta, Giacomo Donati
1Dipartimento di BioScienze, Università degli Studi di Milano, Via Celoria 26, 20133 Milano, Italy.
Cell
|January 22, 2013
概括
转录因子NF-Y由NF-YA和NF-YB/NF-YC子单元组成,具有基因组折叠域,像核细胞一样结合DNA. 这种结合促进了CCAAT促进体中的染色质修饰,这表明其他基因组域蛋白具有类似的功能.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 结构生物学 结构生物学
背景情况:
- CCAAT盒是一个常见的真核生物促进元件.
- NF-Y是一种特定序列的转录因子,对基因调节至关重要.
- NF-Y包括NF-YA和NF-YB/NF-YC子单元,后者含有基因组折叠域 (HFD).
研究的目的:
- 阐明NF-Y与CCAAT框结合的结构基础.
- 为了了解NF-Y的核细胞样性质的功能意义.
- 探索NF-YB无处不在和转录激活之间的关系.
主要方法:
- 进行X射线晶体学以确定与CCAAT寡核酸结合的NF-Y的结构.
- 突变分析以调查特定氨基酸残留物的作用.
- 生物化学测试以评估无处不在和转录活性.
主要成果:
- NF-Y的HFD二聚体结合了DNA的糖酸盐骨干,模仿了核细胞组合.
- NF-YA将一个α螺旋线插入DNA小槽,用于特定序列的CCAAT盒子识别.
- 在Lys138处的NF-YB无化在结构和功能上相当于H2B Lys120单化,这是转录激活的关键步骤.
结论:
- NF-Y作为特定序列的转录因子,具有与核细胞相似的DNA结合特性.
- 结合NF-Y有助于在CCAAT促进剂中建立允许的染色质修饰.
- 其他含有HFD的蛋白质也可能使用类似的机制来结合DNA和调节基因.
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Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
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