THE ACCURACY OF REVERSE-TRANSCRIPTASE FROM HIV-1
THE ACCURACY OF REVERSE-TRANSCRIPTASE FROM HIV-1
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DOI：
10.1126/science.2460925
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发表时间：
1988-11-25
期刊：
影响因子：
56.9
通讯作者：
KUNKEL, TA
中科院分区：
文献类型：
--
作者：
ROBERTS, JD;BEBENEK, K;KUNKEL, TA
进行了一项研究，以确定体外由来自人免疫缺陷病毒I型（HIV-1）的逆转录酶催化的DNA合成的保真度。与其他逆转录病毒逆转录酶一样，HIV-1酶不通过核酸外切酶校正错误。用基于M13 mp2的保真度测定法进行的测量表明，从病毒颗粒或从用表达克隆基因的质粒感染的大肠杆菌细胞中分离的HIV-1酶是异常不准确的，每个掺入的可检测核苷酸的平均错误率为1/1700。事实上，它是迄今为止所描述的最不精确的逆转录酶，其精确度是从禽类成髓细胞瘤病毒或鼠白血病病毒中分离的聚合酶的十分之一，后者的平均错误率为. apprx。1/17，000和. apprx。1/30，000，分别。HIV-1聚合酶产生的突变的DNA序列分析表明，碱基替换，添加和删除的错误都产生了。某些模板位置是突变热点，其中错误率可高达每70个聚合核苷酸1个。这些数据与HIV-1基因组的异常多样性是由易错逆转录造成的这一观点是一致的。
A study was conducted to determine the fidelity of DNA synthesis catalyzed in vitro by the reverse transcriptase from a human immunodeficiency virus type I (HIV-1). Like other retroviral reverse transcriptases, the HIV-1 enzyme does not correct errors by exonucleolytic proofreading. Measurements with M13mp2-based fidelity assays indicated that the HIV-1 enzyme, isolated either from virus particles or from Escherichia coli cells infected with a plasmid expressing the cloned gene, was exceptionally inaccurate, having an average error rate per detectable mucleotide incorporated of 1/1700. It was, in fact, the least accurate reverse transcriptase described to date, one-tenth as accurate as the polymerases isolated from avian myeloblastosis or murine leukemia viruses, which have average error rates of .apprx. 1/17,000 and .apprx. 1/30,000, respectively. DNA sequence analyses of mutations generated by HIV-1 polymerase showed that base substitution, addition, and deletion errors were all produced. Certain template positions were mutational hotspots where the error rate could be as high as 1 per 70 polymerized nucleotides. The data are consistent with the notion that the exceptional diversity of the HIV-1 genome results from error-prone reverse transcription.