在PCAF基因素乙酶复合体内,基因素样TAFs具有基因素样性
V V Ogryzko1, T Kotani, X Zhang
1Laboratory of Molecular Growth Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
Cell
|July 23, 1998
概括
参与转录和细胞循环调节的PCAF复合体含有20多种蛋白质,包括在TFIID中发现的TBP相关因子 (TAF). 这表明这些转录调节复合体之间有共同的功能作用.
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.
- 基因规则 基因规则
背景情况:
- PCAF基因组乙酶对于调节转录,细胞周期进展和分化至关重要.
- 了解PCAF的分子机制对于破译其调节作用至关重要.
研究的目的:
- 为了研究PCAF复合体的蛋白质组成.
- 识别新的子单元及其与已知的转录因子 (如TFIID) 的关系.
主要方法:
- 对PCAF复合物的生物化学分析.
- 使用诸如质谱 (隐含) 等技术识别蛋白质子单元.
- 小单元相互作用的表征.
主要成果:
- PCAF复合体包括20多种不同的多.
- 几个子单位与TBP相关因子 (TAFs) 完全相同,它们是TFIID复合体的组成部分.
- 该PCAF复合体包含质组含有因子,包括与TFIID共享的质组H3和H2B类子单元 (hTAF(II) 31和hTAF(II) 20/15).
- 确定了新的子单元:一种与hTAF相互作用的素H4类子单元和一个与hTAF相似的WD40重复含有子单元.
结论:
- PCAF复合体与TFIID具有重要的结构和潜在的功能相似之处.
- 存在TAFs和基因组含因子表明PCAF在基底转录启动中的作用.
- 新的子单位表明PCAF复合体的独特调节功能超出其已知的乙酶活性.
相关概念视频
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Acetylation
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02:25Spreading of Chromatin Modifications
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02:30Histone Variants at the Centromere
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02:38Heterochromatin
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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...
02:32Histone 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,...
01:12The Nucleosome Core Particle
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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...