对于p53对压力的"数字"反应的分子机制
Jessy Safieh1, Ariel Chazan1, Hanna Saleem1
1Department of Biology, Technion, Technion City, Haifa 2300003, Israel.
概括
在p53响应元素 (RE) 中的DNA灵活性决定了基因激活时间. 更灵活的RE允许快速,早期的基因表达,在压力后影响细胞命运决策.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物物理学的生物物理.
背景情况:
- 瘤抑制蛋白p53调节基因表达,以应对细胞压力.
- 控制p53介导基因激活时间的精确分子机制尚不清楚.
- 之前的研究表明,p53响应元素 (RE) 的DNA扭曲灵活性会影响交换激活.
研究的目的:
- 研究p53响应元素 (RE) 中的DNA灵活性在确定基因激活的时间和水平方面的作用.
- 为了将p53 RE的灵活性与p53-目标基因表达的功能结果相关联.
主要方法:
- 计算大约200个p53RE的DNA灵活性.
- 在RE灵活性和已知的p53-目标基因的功能途径之间的相关性分析.
- 实验验证选择的p53 RES的结构性质.
- 报告者基因测试用于评估由灵活与刚性RE驱动的基因表达.
- 对已公布的内源mRNA水平与RE灵活性相关的分析.
主要成果:
- 在压力下快速激活的基因与晚些时候激活的基因相比,具有显著更灵活的RE.
- 来自灵活RE的报告者基因表达发生在较低的p53水平和更快的速度.
- 实验验证证了来自不同途径的p53 RE的独特结构性质.
- 对内源基因表达的分析表明,RE灵活性是早期和晚期p53响应基因之间的关键差异化因素.
结论:
- p53 RE的DNA灵活性是p53系统中功能选择性的关键决定因素.
- 灵活的RE促进了p53依赖基因表达的初始快速步骤.
- 这种机制有助于细胞在压力后的生存和死亡途径之间的决策过程.
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