Arunagiri C, Macreadie I, Hewish D, Azad A
Biomolecular Research Institute, Division of Biomolecular Engineering, 343 Royal Parade, Parkville, Victoria, Australia.
Apoptosis. 1997;2(1):69-76. doi: 10.1023/a:1026487609215.
We have previously shown that expression of HIV-1 vpr in yeast results in cell growth arrest and structural defects, and identified a C-terminal domain of Vpr as being responsible for these effects in yeast. In this report we show that recombinant Vpr and C-terminal peptides of Vpr containing the conserved sequence HFRIGCRHSRIG caused permeabilization of CD4+ T lymphocytes, a dramatic reduction of mitochondrial membrane potential and finally cell death. Vpr and Vpr peptides containing the conserved sequence rapidly penetrated cells, co-localized with the DNA, and caused increased granularity and formation of dense apoptotic bodies. The above results suggest that Vpr treated cells undergo apoptosis and this was confirmed by demonstration of DNA fragmentation by the highly sensitive TUNEL assay. Our results, together with the demonstration of extracellular Vpr in HIV infected individuals, suggest the possibility that extracellular Vpr could contribute to the apoptotic death and depletion of bystander cells in lymphoid tissues during HIV infection.
我们之前已经表明，HIV-1病毒蛋白R（Vpr）在酵母中的表达会导致细胞生长停滞和结构缺陷，并确定Vpr的C末端结构域是酵母中这些效应的原因。在本报告中，我们表明，重组Vpr和含有保守序列HFRIGCRHSRIG的Vpr C末端肽会导致CD4+ T淋巴细胞通透性增加、线粒体膜电位显著降低，最终导致细胞死亡。含有保守序列的Vpr和Vpr肽迅速穿透细胞，与DNA共定位，并导致细胞粒度增加和致密凋亡小体形成。上述结果表明，Vpr处理的细胞会发生凋亡，这通过高灵敏度的末端脱氧核苷酸转移酶介导的缺口末端标记法（TUNEL）检测到DNA片段化得到证实。我们的结果，连同在HIV感染个体中细胞外Vpr的证明，提示了细胞外Vpr可能在HIV感染期间导致淋巴组织中旁观者细胞凋亡死亡和耗竭的可能性。
