The human immunodeficiency virus transactivator Tat interacts with the RNA polymerase II holoenzyme
The human immunodeficiency virus transactivator Tat interacts with the RNA polymerase II holoenzyme
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DOI：
10.1128/mcb.17.4.1817
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发表时间：
1997-04-01
影响因子：
5.3
通讯作者：
Peterlin, BM
中科院分区：
文献类型：
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作者：
Cujec, TP;Cho, H;Peterlin, BM
人类免疫缺陷病毒（HIV）编码一种转录反式激活因子（Tat），它与一种名为反式激活应答元件（TAR）的RNA发夹结构结合，该结构位于病毒转录起始位点的下游。Tat通过RNA聚合酶II（pol II）刺激全长病毒转录物的产生。在这项研究中，我们证明Tat在细胞中与pol II全酶共免疫沉淀，并且在体外它与纯化的全酶结合。此外，Tat亲和层析从HeLa核提取物中纯化出一种全酶，在添加TBP和TFIIB后，该全酶在体外支持Tat反式激活，这表明它包含Tat功能所需的所有细胞蛋白质。通过证明Tat在没有TAR的情况下与全酶相互作用，我们的数据表明Tat和转录复合物在HIV长末端重复序列上的一步组装。
The human immunodeficiency virus (HIV) encodes a transcriptional transactivator (Tat), which binds to an RNA hairpin called the transactivation response element (TAR) that is located downstream of the site of initiation of viral transcription. Tat stimulates the production of full-length viral transcripts by RNA polymerase II (pol II). In this study, we demonstrate that Tat coimmunoprecipitates with the pol II holoenzyme in cells and that it binds to the purified holoenzyme in vitro. Furthermore, Tat affinity chromatography purifies a holoenzyme from HeLa nuclear extracts which, upon addition of TBP and TFIIB, supports Tat transactivation in vitro, indicating that it contains all the cellular proteins required for the function of Tat. By demonstrating that Tat interacts with the holoenzyme in the absence of TAR, our data suggest a single-step assembly of Tat and the transcription complex on the long terminal repeat of HIV.