ヒストンH3.1およびH3.3複合体は,DNA合成に依存するまたは独立する核細胞組成経路を媒介する
Hideaki Tagami1, Dominique Ray-Gallet, Geneviève Almouzni
1Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115, USA.
Cell
|January 14, 2004
まとめ
H3.1 と H3.3 のヒストンの堆積経路は,それぞれ異なるチャペロン,CAF-1 と HIRA を利用しています. この研究は,H3-H4二元体が核細胞形成と表遺伝子維持における重要な中間物質であることを明らかにしています.
科学分野:
- クロマチンの生物学
- エピジェネティクス エピジェネティクス
- 分子細胞生物学 分子細胞生物学
背景:
- ヒストンH3の堆積はDNA合成と関連している (H3.1) または独立して発生している (H3.3).
- ヒストン変異体の異なる堆積経路を理解することは,染色体組立と表遺伝子遺伝にとって極めて重要です.
研究 の 目的:
- ヒストン変種H3.1とH3.3が別々の経路でクロマチンに沈着するメカニズムを解明する.
- H3.1 と H3.3 の堆積に責任を負うタンパク質複合体を特定し,特徴づけること.
主な方法:
- H3.1 と H3.3.3 のヒストンの堆積装置の浄化
- 浄化された複合体の生化学分析により,関連するチャペロンとヒストンステキオメトリーを特定する.
主要な成果:
- H3.1 (CAF-1) とH3.3 (HIRA) に対して,異なるチャペロン複合体を特定した.
- CAF-1がDNA合成に依存する核細胞組成を媒介し,HIRAがDNA合成に依存しない組成を媒介することを示した.
- 2つの複合体とも単一のH3.1/H3.3-H4ジマーを含んでいることが発見され,それは核細胞形成における保存された二次的な中間物質を示唆している.
結論:
- ヒストンのチャペロンであるCAF-1とHIRAは,H3の堆積経路を明確に指示する.
- H3-H4ジメルは,核細胞形成における重要な中間物質であり,染色体複製中に表遺伝情報維持に影響を与えます.
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
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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...
02:54Nucleosome Remodeling
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Nucleosome remodeling complex
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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...