施瑞克 (SHREC) 是一种用于异色谱转录沉默的效应器复合体
Tomoyasu Sugiyama1, Hugh P Cam, Rie Sugiyama
1Laboratory of Molecular Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Cell
|February 10, 2007
概括
一种新型的蛋白质复合体,SHREC,在裂变酵母 heterochromatin 中调解转录基因沉默. 这个复合体调节核细胞的定位,以建立基因沉默所必需的更高阶染色体结构.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 分子生物学分子生物学
- 染色体生物学 染色体生物学
背景情况:
- 异色素素传统上与转录基因沉默 (TGS) 相关.
- 最近在裂变酵母中的发现表明RNAi介导的转录后基因沉默 (PTGS) 在异染色质中起着作用,挑战了TGS的首要地位.
- 基底的精确分子机制异色TGS仍然不完全理解.
研究的目的:
- 为了识别和描述负责分裂酵母中异色谱转录基因沉默的分子机械.
- 阐明在异色素中调解TGS的效应体复合物的组成和功能.
- 调查这个复合体在染色体组织中的招募机制和调控作用.
主要方法:
- 从裂变酵母中生物化学净化和蛋白质复合物的表征.
- 基因分析,以评估已识别的蛋白质在基因沉默中的功能.
- 染色体免疫沉和局部化研究以确定复杂分布.
- 核细胞定位测定和高阶染色体结构的分析.
主要成果:
- 识别SHREC (沉默枢纽和调节复合体) 作为一个调节异色TGS的多酶效应体复合体.
- SHREC包括一个核心四重奏 (Clr1,Clr2,Clr3,Mit1),分布在异性染色质域中.
- SHREC利用基因组脱乙酶 (Clr3) 和染色体重塑剂 (Mit1) 活动来建立TGS,并调节核素定位以进行更高阶染色体组合.
- 通过Ccq1/Taz1和RNAi机器,SHREC通过Swi6/HP1依赖的机制被招募到端粒,并通过Swi6/HP1依赖的机制被招募到 euchromatic网站.
结论:
- SHREC是一种关键的效应复合物,用于裂变酵母异种染色体中的转录基因沉默.
- 该综合体的活动,包括核细胞定位调节,对于建立功能性异质染色素至关重要.
- SHREC集成了不同的招聘途径,以确保其在不同基因组区域的本地化和功能.
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Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
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Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
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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...
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