Higher fidelity of RNA-dependent DNA mispair extension by M184V drug-resistant than wild-type reverse transcriptase of human immunodeficiency virus type 1.
Higher fidelity of RNA-dependent DNA mispair extension by M184V drug-resistant than wild-type reverse transcriptase of human immunodeficiency virus type 1.
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与人类免疫缺陷病毒 1 型野生型逆转录酶相比，M184V 耐药性的 RNA 依赖性 DNA 错配延伸保真度更高。
DOI：
10.1093/nar/25.22.4532
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发表时间：
1997
影响因子：
14.9
通讯作者：
M. Wainberg
中科院分区：
文献类型：
--
作者：
M. Hsu;M. Hsu;P. Inouye;P. Inouye;Lisa F. Rezende;N. Richard;N. Richard;Zhuo Li;V. Prasad;M. Wainberg;M. Wainberg
人类免疫缺陷病毒1型(HIV-1)的逆转录酶(RT)与其他逆转录病毒的RT和细胞DNA聚合酶相比具有较低的保真度。我们和其他人之前已经发现，M184V突变的HIV-1 RT的DNA依赖DNA聚合(DDDP)的保真度显著高于野生型RT。含有M184V替换的病毒在体外和接受3TC单一治疗的患者中对(-)-2‘-二脱氧-3’-硫代胞苷(3TC)具有高度抗药性。确定M184V RT的RNA依赖DNA聚合(RDDP)与野生型相比的保真度是有意义的，因为这一步骤首先发生在逆转录中；在这一步骤中所犯的错误可能会被复制到后续的聚合步骤中。使用体外错配引物延伸试验，M184V突变RT的错配延伸频率比野生型RT降低了3-49倍。M184V与野生型RT的保真度差异在A：G(49倍)和A：C(16倍)错对的延伸上最为显著，仅在A：A错对的延伸上略有下降(3倍)。含有蛋氨酸到异亮氨酸(M184I)突变的RT显示，与野生型相比，RDDP的保真度只有轻微的增加，从1.5到6倍不等。在所测试的三个RT中，野生型RT最容易出错，错配延伸频率从6.674×10(-1)到7.454×10(-2)不等。
Reverse transcriptase (RT) of human immunodeficiency virus type 1 (HIV-1) has low fidelity compared with RTs of other retroviruses and cellular DNA polymerases. We and others have previously found that the fidelity of DNA-dependent DNA polymerization (DDDP) of M184V-mutated HIV-1 RT is significantly higher than that of wild-type RT. Viruses containing the M184V substitution are highly resistant to (-)-2'-dideoxy-3'-thiacytidine (3TC) in vitro and in patients treated with 3TC monotherapy. It was of interest to determine the fidelity of RNA-dependent DNA polymerization (RDDP) of M184V RT compared with wild-type because this step occurs first in reverse transcription; errors made during this step may be copied in subsequent polymerization steps. Using an in vitro mispaired primer extension assay, M184V-mutated RT exhibited 3-49-fold decreased frequency of mispair extension compared with wild-type RT. Fidelity differences between M184V and wild-type RT were most marked in extension of A:G (49-fold) and A:C (16-fold) mispairs, with only a marginal (3-fold) decrease in the extension of A:A mispairs. RT containing a methionine to isoleucine (M184I) mutation showed only slight increases in RDDP fidelity compared with wild-type, ranging from 1.5- to 6-fold increases. Of the three RTs tested, wild-type RT was the most error-prone, with mispair extension frequencies ranging from 6.674 x 10(-1) to 7.454 x10(-2).