Asf1,一个爱情座椅对于一个基斯顿夫妇
1Department of Carcinogenesis, Science Park Research Division, M.D. Anderson Cancer Center, Smithville, TX 78957, USA.
Cell
|November 4, 2006
概括
结合素H3/H4的第一个晶体结构,揭示了素Aspf1与素H3/H4结合的第一个晶体结构,揭示了素如何帮助核细胞分解. Asf1阻断了四聚体的形成,并改变了基因素H4的构造.
科学领域:
- 分子生物学分子生物学
- 结构生物学是结构生物学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 基因组伴侣对于DNA复制和修复至关重要.
- 核细胞分解是染色体调节的一个关键步骤.
- 了解伴随体 - 基因素相互作用对于染色质动态至关重要.
研究的目的:
- 确定与H3 / H4异构体结合的基因素辅助子 (Asf1) 的第一个晶体结构.
- 阐明基因组辅助子促进核细胞组分的机制.
- 为了深入了解基因组体 - 沙佩龙相互作用的结构基础.
主要方法:
- 在X射线晶体学.
- 蛋白质结构的确定蛋白质结构的确定
- 生物化学测定 生物化学测定
主要成果:
- 确定了Asf1与H3/H4异构体复合的晶体结构.
- Asf1被证明可以物理地阻止 (H3/H4) 2四聚合物的形成.
- 组织素H4的C端在与Asf1.1结合时经历了显著的构造变化.
结论:
- 该结构为Asf1在核细胞分解中的作用提供了分子基础.
- Asf1充当了守门员,控制了组织蛋白四聚体的形成.
- 随伴蛋白结合后,组织蛋白的形状变化对于染色质重塑至关重要.
相关概念视频
Nucleosome 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...
Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Histone Variants at the Centromere
Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as “mutant” forms that replace their canonical histone counterparts in the nucleosomes. Specific post-translational modifications on the histone variants enable further chromatin complexity and regulate tissue-specific gene expression. The most common histone variants are from histone H2A, H2B, and linker histone H1 families. However, several variants of histone H3 variants are also...
The 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...
Histone Modification
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone deacetylase,...
The 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...


