Wang J J, Lu Y, Ratner L
Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, Republic of China.
J Gen Virol. 1994 Oct;75 ( Pt 10):2607-14. doi: 10.1099/0022-1317-75-10-2607.
The 96 amino acid viral protein R (Vpr) of human immunodeficiency virus type 1 (HIV-1) was detected during virus assembly in intracellular vacuoles and at the plasma membrane on peripheral blood mononuclear cells. In both immature and mature virus particles, Vpr was located immediately beneath the viral envelope, colocalizing with the core structural protein, Gag p24. Vpr was present in intracellular HIV-1 wild-type virions at 50% of the level found in extracellular HIV-1 particles. Cells infected with HIV-1 strains with C-terminal truncations of Vpr manifested a different pattern of Vpr expression. A mutant with an alteration of amino acids 79 to 85 exhibited a 23% reduction in total levels of Vpr expression, but a marked accumulation of Vpr in intracellular rather than extracellular virions. A mutant with the last 17 amino acids of Vpr deleted expressed only 10% of wild-type levels of Vpr. These observations indicate that Vpr is incorporated into virions from the cytoplasmic aspect of either the vacuolar or plasma membrane. Furthermore, the proportion of Vpr on intracellular compared to extracellular virions is affected by a specific locus within the protein.
在1型人类免疫缺陷病毒（HIV-1）装配过程中，可在外周血单核细胞的细胞内液泡和质膜中检测到由96个氨基酸组成的病毒蛋白R（Vpr）。在未成熟和成熟病毒颗粒中，Vpr均位于病毒包膜下方，与核心结构蛋白Gag p24共定位。Vpr在细胞内HIV-1野生型病毒体中的含量为细胞外HIV-1颗粒中含量的50%。感染了Vpr C末端截短的HIV-1毒株的细胞表现出不同的Vpr表达模式。一个氨基酸79至85发生改变的突变体，其Vpr表达总量降低了23%，但Vpr在细胞内而非细胞外病毒体中显著积累。一个缺失Vpr最后17个氨基酸的突变体，其Vpr表达水平仅为野生型水平的10%。这些观察结果表明，Vpr是从液泡膜或质膜的细胞质面掺入病毒体的。此外，细胞内与细胞外病毒体上Vpr的比例受该蛋白内一个特定位点的影响。
