由HIV-1 Tat通过异质RNA结合蛋白进行转激活
1Howard Hughes Medical Institute, University of California, San Francisco 94143-0724.
Cell
|August 24, 1990
概括
人类免疫缺陷病毒1型 (HIV-1) Tat蛋白激活病毒基因表达. 这项研究将Tat与外衣蛋白融合在一起,以显示它直接结合TARRNA,独立于其他因素.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 生物化学 生物化学
背景情况:
- 人类免疫缺陷病毒1型 (HIV-1) 转激活剂Tat蛋白对于病毒基因表达和复制至关重要.
- 塔特与一种特定的RNA结构相互作用,即TAR (转激活反应) 干循环,位于病毒转录的5'端.
研究的目的:
- 为了研究HIV-1 Tat蛋白的作用机制.
- 为了映射Tat. 的功能域.
- 要确定Tat的转激活功能是否依赖于TARRNA或其他结合蛋白.
主要方法:
- 通过将HIV-1 Tat蛋白与菌体MS2外套蛋白,一种RNA结合蛋白合并,构建了一个混合蛋白.
- 在HIV-1长终端重复 (LTR) 中的转激活响应 (TAR) 元素被MS2运算机序列取代,这是外套蛋白的RNA标.
- 对运算子序列的突变分析和Tat蛋白内的缺失进行了评估,以评估它们对转激活的影响.
主要成果:
- 混合Tat-coat蛋白成功地转激活了含有原生TAR序列或操作者序列的HIV-1LTRs.
- 削弱外套蛋白与操作者的结合的突变在体外导致体内转激活的减少.
- 混合蛋白的Tat部分内的删除允许识别Tat的激活和RNA结合域.
结论:
- 艾滋病毒-1 Tat介导的转激活可以独立于TAR RNA和DNA结合蛋白发生.
- 塔特通过与TAR RNA干循环结构的直接相互作用,对HIV-1转录产生影响.
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