Zhang S, Pointer D, Singer G, Feng Y, Park K, Zhao L J
Institute for Molecular Virology, St. Louis University School of Medicine, 3681 Park Avenue, St. Louis, MO 63110, USA.
Gene. 1998 Jun 8;212(2):157-66. doi: 10.1016/s0378-1119(98)00178-4.
Human immunodeficiency virus type 1 (HIV-1) viral protein R (Vpr) is a 15kDa regulatory protein packaged in the HIV-1 virion. Although the molecular mechanism of Vpr function during viral replication remains elusive, Vpr has been found to possess interesting biological activities, including cell-cycle arrest at the G2/M check point, promotion of the HIV-1 pre-integration complex for nuclear transport, and a low but significant level of transcriptional activation of a variety of viral and cellular promoters. We now present data suggesting that HIV-1 Vpr is a nucleic-acid-binding protein. This activity of Vpr was demonstrated by DNA-cellulose chromatography, antibody co-immunoprecipitation, and gel electrophoretic mobility shift assays. By mutational analysis, the C-terminal region of Vpr, which is rich in basic amino-acid residues, was shown to be critical for Vpr binding to nucleic acids. The nucleic-acid-binding activity of Vpr is consistent with several biological activities of Vpr and may provide an important clue for understanding the molecular interactions between HIV-1 and the host cells.
1型人类免疫缺陷病毒（HIV-1）的病毒蛋白R（Vpr）是一种包装在HIV-1病毒颗粒中的15kDa调节蛋白。尽管Vpr在病毒复制过程中的分子机制仍不清楚，但已发现Vpr具有有趣的生物学活性，包括在G2/M检查点使细胞周期停滞、促进HIV-1预整合复合物的核运输以及对多种病毒和细胞启动子具有低但显著水平的转录激活作用。我们现在提供的数据表明，HIV-1 Vpr是一种核酸结合蛋白。Vpr的这种活性通过DNA纤维素色谱法、抗体共免疫沉淀法和凝胶电泳迁移率变动分析得以证实。通过突变分析表明，Vpr富含碱性氨基酸残基的C末端区域对于Vpr与核酸的结合至关重要。Vpr的核酸结合活性与Vpr的几种生物学活性一致，可能为理解HIV-1与宿主细胞之间的分子相互作用提供重要线索。
