结构基础的识别H3K56-乙化组合素H3-H4由陪伴者Rtt106的识别
1Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Nature
|February 7, 2012
概括
基因组伴侣Rtt106通过其N终端和PH域结合H3-H4,识别乙化H3K56ac用于DNA复制和修复. 这种相互作用对于基因沉默和DNA损伤反应至关重要.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 染色体动力学 染色体动力学
背景情况:
- 染色体结构的动态,由基质子的翻译后修饰调节,影响与DNA相关的过程.
- 基因组H3 lysine 56乙化 (H3K56ac) 对于核细胞组装和拆卸至关重要.
- 歇斯顿伴侣素Rtt106促进H3K56ac的沉积,但其结合机制尚不清楚.
研究的目的:
- 阐明Rtt106识别和结合H3-H4复合物的分子机制,特别是H3K56ac.
- 研究Rtt106在DNA复制,修复和转录过程中的染色质调节中的作用.
主要方法:
- 生物化学试验用于研究蛋白质与蛋白质相互作用.
- Rtt106领域的结构分析.
- 在Saccharomyces cerevisiae中进行功能性测试.
主要成果:
- Rtt106利用其N端域进行同位体化和H3-H4相互作用,独立于乙化.
- Rtt106的双倍斑素同质 (PH) 域与H3的K56-含有区域结合,对H3K56ac.有增强的亲和力.
- 一个模型,其中Rtt106二聚体插入H3-H4四聚体,与PH域参与H3K56ac网站.
结论:
- Rtt106采用H3-H4的组合识别策略,涉及乙化依赖和独立的相互作用.
- Rtt106-H3-H4相互作用对于维持基因沉默和促进DNA损伤反应至关重要.
相关概念视频
02:32Histone 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,...
02:32Histone 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,...
02:25Spreading of Chromatin Modifications
The histone proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are methylation, acetylation, phosphorylation, and ubiquitination of lysine amino acids in the histone H3 tail region. These histone modifications have specific meaning for the cell. Hence, they are called "histone code". The protein complex involved in histone modification is termed as "reader-writer" complex.
Writers
The writer is an enzyme that can...
Writers
The writer is an enzyme that can...
02:38Heterochromatin
The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions that take up more dye are called heterochromatin. Heterochromatin is further classified into two forms – constitutive heterochromatin and facultative heterochromatin.
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
Constitutive heterochromatin: It is a highly compact region of chromatin that is mostly concentrated in the centromere and telomere. Unlike euchromatin, the amino acid at 9th...
02:41Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
02:30Histone 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...