Homologous recombination occurs in a distinct retroviral subpopulation and exhibits high negative interference
Homologous recombination occurs in a distinct retroviral subpopulation and exhibits high negative interference
复制标题
DOI：
10.1128/jvi.71.8.6028-6036.1997
复制
发表时间：
1997-08-01
影响因子：
5.4
通讯作者：
Pathak, VK
中科院分区：
文献类型：
--
作者：
Hu, WS;Bowman, EH;Pathak, VK
当逆转录酶转换模板时，同源重组和缺失在逆转录病毒复制期间发生。虽然重组仅通过分子间模板转换（在共包装的RNA之间）发生，但缺失可以通过分子间或分子内模板转换（在同一RNA内）发生。为了直接比较分子内和分子间模板转换的速率，构建了两个基于脾坏死病毒的载体，每个载体含有先前显示以高速率缺失的110-bp的正向重复序列，110-bp的正向重复序列两侧是两组不同的限制性位点标记。这些载体用于形成含有每个亲本载体的RNA的杂合病毒体，通过分析重组和非重组前病毒中同向重复序列侧翼的标记，确定分子内和分子间模板转换的速率，这些分析的结果表明，分子内模板转换比分子间模板转换更有效，并且直接重复缺失主要通过分子内模板转换发生这些研究还表明，逆转录病毒重组发生在不同的病毒亚群内，并表现出高负干扰，由此选择一个重组事件增加了观察到第二个重组事件的概率。
Homologous recombination and deletions occur during retroviral replication when reverse transcriptase switches templates, While recombination occurs solely by intermolecular template switching (between copackaged RNAs), deletions can occur bg an intermolecular or an intramolecular template switch (within the same RNA). To directly compare the rates of intramolecular and intermolecular template switching, two spleen necrosis virus-based vectors were constructed, Each vector contained a 110-bp direct repeat that was previously shown to delete at a high rate, The 110-bp direct repeat was flanked by two different sets of restriction site markers, These vectors were used to form heterozygotic virions containing RNAs of each parental vector, from which recombinant viruses were generated, By analyses of the markers flanking the direct repeats in recombinant and nonrecombinant proviruses, the rates of intramolecular and intermolecular template switching were determined, The results of these analyses indicate that intramolecular template switching is much more efficient than intermolecular template switching and that direct repeat deletions occur primarily through intramolecular template switching events, These studies also indicate that retroviral recombination occurs within a distinct viral subpopulation and exhibits high negative interference, whereby the selection of one recombination event increases the probability that a second recombination event will be observed.