Multiple blocks to human immunodeficiency virus type 1 replication in rodent cells
Multiple blocks to human immunodeficiency virus type 1 replication in rodent cells
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DOI：
10.1128/jvi.74.21.9868-9877.2000
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发表时间：
2000-11-01
影响因子：
5.4
通讯作者：
Cullen, BR
中科院分区：
文献类型：
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作者：
Bieniasz, PD;Cullen, BR
最近鉴定出人类免疫缺陷病毒1型（HIV-1）生命周期早期阶段所需的人类基因产物，这提高了啮齿动物可能被改造以支持HIV-1感染的可能性。因此，我们研究了修饰的小鼠、大鼠和仓鼠细胞系支持HIV-1复制的能力。啮齿类动物细胞，工程支持达特功能的稳定表达的一个允许的细胞周期蛋白T1蛋白，证明能够支持逆转录，整合，和早期基因表达的水平在人类细胞系中观察到的。然而，令人惊讶的是，在小鼠和大鼠成纤维细胞系中，CD 4和辅助受体依赖性病毒进入的水平降低到一个可变但显著的程度。观察到其他转录后缺陷，包括未剪接的HIV-1基因组RNA水平降低和结构基因表达降低。此外，HIV-1 Gag前体通常被低效地加工，并且以基本上非感染性的形式从小鼠和大鼠细胞中分泌不良。与人类细胞相比，这些转录后缺陷共同导致HIV-1复制单个周期内感染性病毒的产量急剧下降（高达10，000倍）。有趣的是，这些缺陷在一种仓鼠细胞系CHO中不太明显，CHO不仅能够以接近人类细胞中观察到的水平产生感染性HIV-1颗粒，而且还可以支持短暂的低水平HIV-1复制。重要的是，在小鼠和大鼠细胞中对感染性病毒产生的阻断是隐性的，因为它们可以通过与未感染的人细胞融合而基本上被抑制。这些研究表明存在一种或多种人基因产物，其在大多数啮齿动物细胞中缺乏或无功能，这对感染性HIV-1病毒体形态发生至关重要。
The recent identification of human gene products that are required for early steps in the human immunodeficiency virus type 1 (HIV-1) life cycle has raised the possibility that rodents might be engineered to support HIV-1 infection. Therefore, we have examined the ability of modified mouse, rat, and hamster cell lines to support productive HIV-1 replication. Rodent cells, engineered to support Tat function by stable expression of a permissive cyclin T1 protein, proved to be able to support reverse transcription, integration, and early gene expression at levels comparable to those observed in human cell lines. Surprisingly, however, levels of CD4- and coreceptor-dependent virus entry were reduced to a variable but significant extent in both mouse and rat fibroblast cell lines. Additional posttranscriptional defects were observed, including a reduced level of unspliced HIV-1 genomic RNA and reduced structural gene expression. Furthermore, the HIV-1 Gag precursor is generally inefficiently processed and is poorly secreted from mouse and rat cells in a largely noninfectious form. These posttranscriptional defects, together, resulted in a dramatically reduced yield of infectious virus (up to 10,000-fold) over a single cycle of HIV-1 replication, as compared to human cells. Interestingly, these defects were less pronounced in one hamster cell line, CHO, which not only was able to produce infectious HIV-1 particles at a level close to that observed in human cells, but also could support transient, low-level HIV-1 replication. Importantly, the blocks to infectious virus production in mouse and rat cells are recessive, since they can be substantially suppressed by fusion with uninfected human cells, These studies imply the existence of one or more human gene products, either lacking or nonfunctional in most rodent cells that are critical for infectious HIV-1 virion morphogenesis.