转录因子IIIC被腺病毒E1A蛋白激活
W K Hoeffler1, R Kovelman, R G Roeder
1Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
Cell
|June 17, 1988
概括
腺病毒E1A通过改变转录因子IIIC (TFIIIC) 来激活RNA聚合酶III转录. 酸化TFIIIC会产生一种更活跃的形式,在病毒感染期间增强基因表达.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 基因规则 基因规则
背景情况:
- 已知腺病毒E1A蛋白刺激RNA聚合酶III基因的转录.
- 之前的研究将负责因子定位为转录因子IIIC (TFIIIC).
研究的目的:
- 研究涉及腺病毒E1A介导转录的TFIIIC的特定形式.
- 阐明TFIIIC活动受到监管的机制.
主要方法:
- 将TFIIIC分成不同的形式的染色学分离.
- 凝转移测试用于分析VA基因-蛋白质复合体.
- 试管体内转录测试用于测量转录活性.
- 酸酶处理以评估TFIIIC表格的相互转换.
主要成果:
- 确定了两种可分离的TFIIIC形式,它们在形成VA基因-蛋白质复合体的能力上有所不同.
- 一种更活跃的TFIIIC形式与更快的促进体结合和增加的盐耐药性有关.
- E1A表达或血清度增加导致活性TFIIIC形式的水平更高.
- 在病毒感染期间,TFIIIC总体度保持不变.
结论:
- 腺病毒E1A对RNA聚合酶III基因的转录激活是由不同形式的TFIIIC介导的.
- TFIIIC 的酸化是控制其活动的关键监管机制.
- 这种酸化事件增强了TFIIIC在病毒基因表达中的作用.
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