原子核核粒子の近くにある対極の大気と水分化のパターン
Christopher K Materese1, Alexey Savelyev, Garegin A Papoian
1Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
Journal of the American Chemical Society
|September 26, 2009
まとめ
移動性イオンと水分子は核細胞に深く浸透し,DNA中和とクロマチンの折り畳みを助けます. この研究は,イオンと水素の相互作用が,より高次のクロマチンの構造にどのように影響するかを明らかにしています.
科学分野:
- バイオフィジックス 生物物理学
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
背景:
- クロマチンの折り畳みは,DNAの圧縮と遺伝子調節に不可欠です.
- クロマチンの基本的な単位である核細胞は,DNAの中和とアクセシビリティを理解する上で課題を提示します.
- 移動性イオンと水の核細胞構造と機能における役割は,詳細な調査を必要とする.
研究 の 目的:
- 全原子分子ダイナミクスのシミュレーションを使用して,核細胞周りの移動イオンの凝縮を調査する.
- ヌクレオソーム内のDNA中和のメカニズムを解明する.
- 高位クロマチンの構造に対するイオンと水分化の相互作用の影響を調査する.
主な方法:
- 広範な全原子分子ダイナミクスシミュレーション.
- 原子核核粒子の周りのイオン濃縮と分布の分析.
- ヌクレオソームDNA中和とコンフォーマーションダイナミクスの研究.
主要な成果:
- 核細胞は,100ナノ秒のスケールで最小限の構成変動を示します.
- 核体DNAは,自由DNAよりもヒストン電荷と移動性イオンによってより効果的に中和されます.
- ナトリウムイオン凝縮はヒストン核の酸性パッチによって著しく影響を受けます.
- 千以上の水分子が核体に浸透し,深層のイオン浸透を促進します.
結論:
- 核細胞内のイオンと水分相互作用は,クロマチンの凝縮に重要な役割を果たします.
- この発見は,核内のDNA中和とアクセシビリティを制御する物理的メカニズムについての洞察を提供します.
- この研究は,より高いレベルの繊維形成におけるイオン,水,およびクロマチンの構造の複雑な相互作用を理解するのに寄与します.
関連する概念動画
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...
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...
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...
02:10The 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.
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...
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...
02:54Nucleosome Remodeling
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
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...