Laboratory of Molecular Virology, International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano, 99, 34012 Trieste, Italy.
Retrovirology. 2011 Jul 20;8:60. doi: 10.1186/1742-4690-8-60.
Central to the fully competent replication cycle of the human immunodeficiency virus type 1 (HIV-1) is the nuclear export of unspliced and partially spliced RNAs mediated by the Rev posttranscriptional activator and the Rev response element (RRE).
Here, we introduce a novel method to explore the proteome associated with the nuclear HIV-1 RNAs. At the core of the method is the generation of cell lines harboring an integrated provirus carrying RNA binding sites for the MS2 bacteriophage protein. Flag-tagged MS2 is then used for affinity purification of the viral RNA. By this approach we found that the viral RNA is associated with the host nuclear matrix component MATR3 (Matrin 3) and that its modulation affected Rev activity. Knockdown of MATR3 suppressed Rev/RRE function in the export of unspliced HIV-1 RNAs. However, MATR3 was able to associate with Rev only through the presence of RRE-containing viral RNA.
In this work, we exploited a novel proteomic method to identify MATR3 as a cellular cofactor of Rev activity. MATR3 binds viral RNA and is required for the Rev/RRE mediated nuclear export of unspliced HIV-1 RNAs.
人类免疫缺陷病毒 1 型（HIV-1）完全有能力复制周期的核心是反式激活因子 Rev 和 Rev 反应元件（RRE）介导的未剪接和部分剪接 RNA 的核输出。
在这里，我们引入了一种新的方法来探索与核 HIV-1 RNA 相关的蛋白质组。该方法的核心是构建携带 MS2 噬菌体蛋白 RNA 结合位点的整合前病毒的细胞系。然后，使用 Flag 标记的 MS2 进行病毒 RNA 的亲和纯化。通过这种方法，我们发现病毒 RNA 与宿主核基质成分 MATR3（Matrin 3）相关，其调节会影响 Rev 活性。MATR3 的敲低抑制了未剪接 HIV-1 RNA 的 Rev/RRE 功能。然而，MATR3 只有在存在含有 RRE 的病毒 RNA 时才能与 Rev 结合。
在这项工作中，我们利用一种新的蛋白质组学方法鉴定了 MATR3 作为 Rev 活性的细胞辅助因子。MATR3 结合病毒 RNA，是 Rev/RRE 介导的未剪接 HIV-1 RNA 核输出所必需的。
