一种新型的CDK9相关的C型环林直接与HIV-1 Tat相互作用,并介导其高亲和度,循环特定的结合到TAR RNA
1Regulatory Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037-1099, USA.
Cell
|March 10, 1998
概括
艾滋病毒-1 Tat蛋白使用环林T来增强其与TAR RNA的结合,从而促进转录. 这种相互作用对病毒基因表达至关重要,并且可以通过动物细胞中的人类环林T来挽救.
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:
- 艾滋病毒-1 Tat蛋白对于病毒转录延长至关重要.
- 塔特与TAR RNA干循环结构结合,以调节基因表达.
- 没有完全理解Tat介导转录增强的精确机制.
研究的目的:
- 为了识别与HIV-1 Tat.交互的新型细胞因子.
- 阐明环林T在Tat介导的转录调节中的作用.
- 调查 Tat 增强其与 TAR RNA 相互作用的机制.
主要方法:
- 蛋白相互作用研究,以隔离和表征环林T.
- 对Tat:TARRNA结合亲和力和特异性的分析.
- 功能性试验涉及细胞系中环林T的过度表达.
主要成果:
- 发现了一种新型的87kDa环C相关蛋白,环T.
- 循环T专门与Tat交易激活域进行交互,并与CDK9.9合作.
- 塔特-环林T相互作用显著增强了Tat:TARRNA结合亲和力和特异性.
- 人类环素T的过度表达拯救了非允许的动物细胞中的Tat活性.
结论:
- 艾滋病毒-1 Tat通过对TAR RNA的合作结合将环素T-CDK9招募到RNAPII中.
- 环素T是Tat介导的转录延长的一个关键辅因子.
- 这种相互作用代表了抗病毒疗法的潜在目标.
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