染色体紧缩和基因组修饰状态之间的双向反解释了Saccharomyces cerevisiae的异染色体 bistability
Ander Movilla Miangolarra1, Daniel S Saxton2, Zhi Yan2
1Department of Computational and Systems Biology, John Innes Centre, Norwich NR4 7UH, United Kingdom.
概括
染色体紧缩和基因素修改创建一个反循环,控制基因沉默. 这种动态相互作用解释了基因如何在活跃状态和静默状态之间切换.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 系统生物学 系统生物学
背景情况:
- 染色体紧缩与通过阻断促销器访问来抑制基因沉默有关.
- 一个假设表明,染色体紧缩和基质子修饰状态双向相互作用,以控制可分两位的转录状态.
研究的目的:
- 严格测试染色体紧缩和基因组修饰状态之间的双向反假设.
- 开发一个数学模型,用于Saccharomyces cerevisiae中HMR位点的动态.
主要方法:
- 开发了一种数学模型,其中包含了基质子的修改,沉默蛋白和动态位置大小.
- 建模的乙化依赖的三维位点尺寸变化.
- 使用该模型预测不同基因长度的切换率的变化.
主要成果:
- 该模型准确地复制了关于切换速率和蛋白质/激素修饰水平的实验数据.
- 随着局部长度的增加,切换率的预测变化被实验验证.
- 证明了一个反循环,其中压缩增强了沉声器的结合,去除了激活修改并导致进一步的压缩.
结论:
- 染色体紧缩和基因组修饰状态之间的双向反是关键的调节机制.
- 这种机制可能是异色彩区域中可见的转录状态的基础.
- 这些发现强调了物理色素结构在基因调节中的重要性.
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