Somatic cell mutants resistant to retrovirus replication: Intracellular blocks during the early stages of infection
Somatic cell mutants resistant to retrovirus replication: Intracellular blocks during the early stages of infection
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DOI：
10.1091/mbc.10.6.1705
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发表时间：
1999-06-01
影响因子：
3.3
通讯作者：
Goff, SP
中科院分区：
文献类型：
--
作者：
Gao, GX;Goff, SP
为了鉴定参与逆转录病毒生命周期早期阶段的细胞功能，在选择抗感染后分离体细胞突变体。用化学诱变剂处理大鼠2成纤维细胞，并在选择抗感染性后回收单个病毒抗性克隆。对两个克隆进行了详细表征。这两种突变株系对嗜亲性和嗜亲性鼠病毒以及人免疫缺陷病毒1型假型的感染具有抗性。一个克隆显示出对逆转录病毒RNA的逆转录的强烈阻断，包括最早的DNA产物的形成。第二个克隆显示出正常水平的病毒DNA合成，但不允许形成通常在细胞核中发现的环状DNA。细胞分级分离表明，病毒预整合复合物以在易于从野生型细胞中提取复合物的条件下无法提取的形式存在。结果表明，DNA被困在一个非生产性的状态，并从感染细胞的细胞核排除。这两个突变系的特性表明宿主基因产物在逆转录前后都发挥着重要作用。
To identify cellular functions involved in the early phase of the retroviral life cycle, somatic cell mutants were isolated after selection for resistance to infection. Rat2 fibroblasts were treated with chemical mutagens, and individual virus-resistant clones were recovered after selection for resistance to infection. Two clones were characterized in detail. Both mutant lines were resistant to infection by both ecotropic and amphotropic murine viruses, as well as by human immunodeficiency virus type 1 pseudotypes. One clone showed a strong block to reverse transcription of the retroviral RNA, including formation of the earliest DNA products. The second clone showed normal levels of viral DNA synthesis but did not allow formation of the circular DNAs normally found in the nucleus. Cell fractionation showed that the viral preintegration complex was present in a form that could not be extracted under conditions that readily extracted the complex from wild-type cells. The results suggest that the DNA was trapped in a nonproductive state and excluded from the nucleus of the infected cell. The properties of these two mutant lines suggest that host gene products play important roles both before and after reverse transcription.