染色体改造複合体NURFによって媒介されるATP依存ヒストンオクターマーのスライディング
A Hamiche1, R Sandaltzopoulos, D A Gdula
1Laboratory of Molecular Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4255, USA.
Cell
|July 10, 1999
まとめ
ドロソフィラのNURF複合体 (核細胞再構成因子) は,DNAに核細胞を再配置する. このクロマチンの改造器は,構造的整合性を保ちながらヒストンオクタマーの滑り方を容易にします.
科学分野:
- 分子生物学は分子生物学である.
- クロマチンの生物学
- バイオケミストリー バイオケミストリー
背景:
- ATPに依存するクロマチンの改造複合体は,DNAテンプレートプロセスにおいて重要な役割を果たします.
- ドロソフィラのISWIを含む核細胞改造因子 (NURF) は,染色体動態の重要な役割を果たしています.
研究 の 目的:
- ドロソフィラNURFが核細胞を再構成するメカニズムを調査する.
- NURF媒介による改造過程における核細胞体の動きと整合性を特徴づける.
主な方法:
- hsp70プロモーターDNAのモノヌクレオソームの再構成.
- NURFおよび Exo III 消化を用いた核細胞の再分配の分析.
- 改造中のコアヒストンの保持の評価.
主要な成果:
- NURFは,DNA上のモノヌクレオソームの双方向的な再分配を触媒化する.
- 核細胞は急速に支配的な位置をとり, cis.で動きが起こります.
- ヒストンのオクターマーの整合性は,改造プロセスを通して維持され,短距離のスライドを示唆しています.
結論:
- ドロソフィラNURFは,ヒストンオクタメールの短距離スライドを促進することによって,核細胞を再構成します.
- 複合体は,核細胞の再定位のための活性化エネルギーを低下させるように見える.
- NURF媒介による改造は,核子の全体的な構造を保ちます.
関連する概念動画
02:33The Nucleosome
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DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
02:10The Nucleosome Core Particle
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The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
02:54Nucleosome Remodeling
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Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
02:33The Nucleosome
DNA in a human cell is almost 2m long and it is packed inside a tiny nucleus that is only a few microns in diameter. The level of compaction of DNA inside the nucleus is astonishing. It is organized into several sequentially higher levels of compaction to fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
01:19The Nucleosome
Human DNA is almost two meters long. However, it is compressed inside a tiny nucleus measuring only a few microns in diameter. To make this degree of compaction possible, DNA is organized into several sequential levels so that it can fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
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...