核細胞核は,転写ポリメラーゼの経路から移される
1Laboratory of Molecular Biology, National Institutes of Health, Bethesda, Maryland 20892.
Cell
|October 2, 1992
まとめ
トランスクリプションの過程で,核細胞核が異動し,DNAの他の部分に再構成されます. このヒストンのオクトーマー移転は,活性遺伝子発現中にDNAをナビゲートするメカニズムを示唆する.
科学分野:
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
- 遺伝子規制 遺伝子規制
背景:
- 核細胞は,真核生物のDNA包装の基本的な単位である.
- 転写中の核細胞動態を理解することは,遺伝子調節に不可欠です.
- 以前のモデルでは,ニュクレオソームのポリメラーゼ通過のための様々なメカニズムが提案されました.
研究 の 目的:
- トランスクリプション中に核細胞核の運命を決定するために.
- DNAのニュクレオソームの移転と再構成を調査する.
- ヌクレオソームDNAによる転写のメカニズムを解明する.
主な方法:
- 短いDNA断片に核細胞核の組み立て.
- ヌクレオソームを含むDNAをSP6RNAポリメラーゼプロモーターとターミネーターを備えたプラズミドに結合する.
- in vitroトランスクリプション後の核細胞分布の分析.
主要な成果:
- 核細胞核は,転写の欠如で安定したままでした.
- SP6RNAポリメラーゼによるトランスクリプションはヒストンオクタマーを位移させた.
- 変位したヒストンオクタマーは,ニュークレオソームの核を新しい部位で,しばしば転写されていない領域でリフォームした.
結論:
- この研究は,転写中の核細胞の移転の直接的な証拠を提供します.
- 発見は,核個体を通しての転写のためのいくつかの提案されたモデルを排除する.
- 結果は,受容体DNA部位への移転によって,核粒子の移転が起こることを示唆しています.
関連する概念動画
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02:35Transcription 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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01:12The Nucleosome Core Particle
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...
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...