在多拷贝基因位点建立和维持替代色素状态
Manuel Wittner1, Stephan Hamperl, Ulrike Stöckl
1Lehrstuhl Biochemie III, Universität Regensburg, Institut für Biochemie, Genetik und Mikrobiologie, 93053 Regensburg, Germany.
Cell
|May 14, 2011
概括
酵母细胞通过转录依赖的核细胞去除和复制依赖的组合来动态平衡开放和关闭的核细胞RNA (rRNA) 基因染色体状态,确保核细胞生产和基因组完整性.
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.
- 染色体生物学 染色体生物学
背景情况:
- 细胞基因组包含100多个核糖体RNA (rRNA) 基因拷贝,存在于转录活性开放色素或非活性闭合色素状态.
- 开放的rRNA基因对核糖体生物生成至关重要,而闭合状态则保持基因组完整性.
- 这些染色体状态的动态调节对于细胞功能和增殖至关重要.
研究的目的:
- 为了研究在繁殖酵母中的rRNA基因中平衡开放和闭合染色质状态的分子机制.
- 阐明转录和复制在建立和维持rRNA基因染色质中的作用.
- 了解HMG盒子蛋白Hmo1在rRNA基因调节中的功能.
主要方法:
- 在酵母细胞中分析染色质状态,使用评估核细胞定位和占用率的技术.
- 研究RNA聚合酶I (Pol I) 转录和DNA复制之间的相互作用.
- 研究Hmo1与rRNA基因的结合及其对染色质结构的影响.
主要成果:
- 转录依赖的核细胞体去除和复制依赖的核细胞体组合之间的动态平衡控制着rRNA基因染色体状态.
- RNA聚合酶I (Pol I) 转录对于招募HMG盒蛋白Hmo1来打开rRNA基因至关重要.
- Hmo1对抗复制独立的核细胞沉积,在S阶段之外保持开放的染色质状态.
结论:
- 通过复制和转录的相反力量建立了rRNA基因染色体状态的平衡.
- 对于rRNA基因的染色体状态在每个细胞周期中都会动态重置.
- 这种动态调节确保了足够的核糖体生产和基因组稳定性的维持.
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