一个核细胞核被转移出转录聚合酶的路径
1Laboratory of Molecular Biology, National Institutes of Health, Bethesda, Maryland 20892.
Cell
|October 2, 1992
概括
在转录过程中,核细胞核被取代,并在DNA的其他地方进行改革. 这种基因组八位体转移表明了在活跃基因表达过程中导航DNA的机制.
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.
- 基因规则 基因规则
背景情况:
- 核细胞是真核生物中DNA包装的基本单元.
- 了解转录期间的核细胞体动力学对于基因调节至关重要.
- 之前的模型提出了聚合酶穿越核体的各种机制.
研究的目的:
- 为了确定转录过程中核细胞核的命运.
- 为了研究DNA上的核体的移位和重组.
- 阐明通过核细胞DNA转录的机制.
主要方法:
- 在一个短的DNA片段上组装核细胞核.
- 将含核子组的DNA结合成具有SP6RNA聚合酶促进子和终止子的等离子体.
- 在体外转录后核细胞分布的分析.
主要成果:
- 核细胞核在没有转录的情况下保持稳定.
- 由SP6RNA聚合酶转录取位移了基因素八度体.
- 移位的基因组八聚体在一个新的位置重塑了核细胞核,通常是在未经转录的区域.
结论:
- 这项研究提供了转录过程中核细胞位移的直接证据.
- 这些发现消除了通过核细胞体转录的几种拟议模型.
- 结果表明,核细胞位移通过转移到受体DNA位点而发生.
相关概念视频
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Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
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Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
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