概括
博醇瘤促进剂通过被转录因子AP-1识别的保存DNA动机激活基因表达. 这种结合活性在TPA治疗后迅速增加,表明AP-1
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 细胞信号传递 细胞信号传递
背景情况:
- 勃 Ester 和 TPA 一样是已知的瘤促进剂,影响基因表达.
- 几种TPA诱导基因在它们的促进子区域中共享一个共同的DNA序列动图.
研究的目的:
- 为了确定负责TPA诱导性的DNA元素.
- 确定与这些元素结合的转录因子.
- 为了阐明TPA诱导的基因激活的机制.
主要方法:
- 对TPA诱导基因促进体中保存的DNA基因的分析.
- 合成促进者-报告者基因结构的构建.
- DNase足迹测试用于识别蛋白质-DNA相互作用.
- 位点定向突变发生,以评估DNA基因的作用.
主要成果:
- 在TPA诱导基因促进体中发现了一种保存的9bp动机 (TPA-响应元素,TRE).
- 合成的TRE赋予了TPA诱导性给异质的促进体.
- 转录因子AP-1与TRE结合.
- 在TRE中的突变取消了基底和TPA诱导的活动和AP-1结合.
- 通过转化后机制,TPA治疗迅速增加了TRE结合活性.
结论:
- AP-1 是一个关键的转录因子,调解TPA对基因表达的影响.
- TRE是功能性DNA元素,它结合AP-1并赋予TPA可诱导性.
- TPA信号通路汇聚在AP-1上,导致增强的基因转录.
相关概念视频
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