Evidence that retroviral transduction is mediated by DNA not by RNA.
Evidence that retroviral transduction is mediated by DNA not by RNA.
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有证据表明逆转录病毒转导是由 DNA 而不是 RNA 介导的。
DOI：
10.1073/pnas.87.9.3604
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发表时间：
1990
影响因子：
11.1
通讯作者：
Duesberg,PH
中科院分区：
文献类型：
--
作者：
Goodrich,DW;Duesberg,PH
细胞核酸序列的逆转录病毒转导需要非法的RNA或DNA重组。为了测试假定病毒和细胞 RNA 逆转录过程中通过有效非法重组进行转导的模型，我们测量了具有人工 3' 末端的哈维肉瘤病毒 (HaSV) 通过非法同源重组从辅助莫洛尼病毒 (MoV) 恢复逆转录病毒 3' 末端的能力。为此，用 Harvey 原病毒转化小鼠 NIH 3T3 细胞，然后用 MoV 进行双重感染。原病毒缺乏3'长末端重复序列和5'长末端重复序列的非转录区域，以防止输入原病毒再生病毒。 MoV 重复感染由具有 MoV 无关末端的 Harvey 原病毒转化的 3 x 10(6) 细胞后，仅生成 0-11 个 HaSV 病灶形成单位。这种低频率与通过莫洛尼原病毒随机整合 10(6)-kilobase 小鼠基因组中转化病毒 ras 基因 3' 的非法 DNA 重组一致。当部分鼠病毒包膜（env）基因连接到ras的3'时，根据与MoV的env的同源程度，产生HaSV的10(2)-10(5)个病灶形成单位。这些重组体均含有共同 env 同源性的 HaSV 特异性序列 5' 和 MoV 特异性序列 3'。它们可能是通过逆转录过程中的重组产生的，而不是通过输入或次级原病毒之间的重组产生的，因为（i）当env序列侧翼有剪接信号时，重组体的产量减少了10倍；（ii）没有逆转录病毒3'末端的HaSV RNA将不足以作为原病毒合成的模板。我们的结论是，逆转录病毒中不存在有效的非法重组。鉴于非法 DNA 重组的已知先例、已知病毒 onc 基因的结构以及我们通过原病毒整合进行非法 DNA 重组的证据，我们更倾向于 DNA 转导模型而不是 RNA 模型。
Retroviral transduction of cellular nucleic acid sequences requires illegitimate RNA or DNA recombination. To test a model that postulates transduction via efficient illegitimate recombination during reverse transcription of viral and cellular RNAs, we have measured the ability of Harvey sarcoma viruses (HaSVs) with artificial 3' termini to recover a retroviral 3' terminus from helper Moloney virus (MoV) by illegitimate and homologous recombination. For this purpose, mouse NIH 3T3 cells were transformed with Harvey proviruses and then superinfected with MoV. The proviruses lacked the 3' long terminal repeat and an untranscribed region of the 5' long terminal repeat to prevent virus regeneration from input provirus. Only 0-11 focus-forming units of HaSV were generated upon MoV superinfection of 3 x 10(6) cells transformed by Harvey proviruses with MoV-unrelated termini. This low frequency is consistent with illegitimate DNA recombination via random Moloney provirus integration 3' of the transforming viral ras gene in the 10(6)-kilobase mouse genome. When portions of murine viral envelope (env) genes were attached 3' of ras, 10(2)-10(5) focus-forming units of HaSV were generated, depending on the extent of homology with env of MoV. These recombinants all contained HaSV-specific sequences 5' and MoV-specific sequences 3' of the common env homology. They were probably generated by recombination during reverse transcription rather than by recombination among either input or secondary proviruses, since (i) the yield of recombinants was reduced by a factor of 10 when the env sequence was flanked by splice signals and (ii) HaSV RNAs without retroviral 3' termini would be inadequate templates for provirus synthesis. We conclude that there is no efficient illegitimate recombination in retroviruses. In view of known precedents of illegitimate DNA recombination, the structure of known viral onc genes, and our evidence for illegitimate DNA recombination via provirus integration, we favor the DNA model of transduction over the RNA model.