非海斯Scm3和海斯CenH3-H4组装了中心分子特异性核细胞的核心
Gaku Mizuguchi1, Hua Xiao, Jan Wisniewski
1Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Building 37, Room 6068, Bethesda, MD 20892-4255, USA.
Cell
|June 19, 2007
概括
一种新型蛋白质,Scm3,对于芽酵母中素H3变体Cse4的中心联结至关重要. Scm3促进了Cse4-H4在中间体的组合,可能取代了正规的H2A-H2B组合素.
科学领域:
- 分子生物学分子生物学
- 染色体生物学 染色体生物学
- 酵母遗传学 酵母遗传学
背景情况:
- 中心色素对于细胞分裂期间精确的染色体分离至关重要.
- 基因素H3变体Cse4是中心核细胞核体的关键组成部分,指导动态细胞组合.
- 对于Cse4在中间体中被纳入和维持的精确机制,人们对其理解尚不完全.
研究的目的:
- 识别与Cse4相互作用的蛋白质,并参与其中心体局部化.
- 阐明Scm3在中间体染色质的组合和稳定中的作用.
- 为了研究Scm3,Cse4和正规组织组织蛋白之间的结构和功能关系.
主要方法:
- 共同免疫沉和西部斑点检测蛋白质相互作用.
- 复合蛋白的细菌表达和净化用于体外结合试验.
- 组建基因组-DNA复合体.
- 在活体中分析中位素占用率的分析.
主要成果:
- Scm3被确定为一种新型非希斯蛋白,它与Cse4同位,并对其中心体关联有必要.
- Scm3直接与Cse4和基因素H4结合,形成一个稳定的复合体,但不与传统的H3-H4结合.
- 在Scm3中保存的酸性域调解了与Cse4的特定相互作用.
- 结合scm3可以从含有Cse4的素八度体中取代素H2A-H2B.
- 在体内,Scm3与中心分子中H2A,H2B和H2AZ的占用率降低相关.
结论:
- 非希斯蛋白Scm3对于在中心区域的Cse4-H4复合体的组装和维护至关重要.
- Scm3可能在中心核核细胞核细胞核中替代素H2A-H2B二元体.
- 这些发现揭示了中心核细胞组合和功能的独特机制,与散装染色体不同.
相关概念视频
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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
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...
02:30Histone Variants at the Centromere
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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...