Mansky L M
McArdle Laboratory for Cancer Research, University of Wisconsin Medical School, Madison 53706, USA.
AIDS Res Hum Retroviruses. 1996 Mar 1;12(4):307-14. doi: 10.1089/aid.1996.12.307.
An in vivo assay was previously developed for detecting forward mutations in human immunodeficiency virus type 1 (HIV-1) in a single cycle of replication. This system uses the lacZalpha peptide gene as a reporter for mutations, and allows for the rates and types of mutations that occur to be determined. The forward mutation rate for HIV-1 in HeLa cells was found to be 3 x 10(-5) mutations per target base pair per cycle. To test whether the mutation rate was influenced by cell type, the mutation rate of HIV-1 in CEM-A cells, a T lymphoid cell line, was determined. The mutation rate of HIV-1 reverse transcription in CEM-A cells was found to be 4 x 10(-5) mutations per target base pair per cycle. The number and types of mutations observed were similar to that in HeLa cells. Specifically, base substitution mutations predominated, and G-to-A transition mutations were the most common base substitution. G-to-A hypermutants were also characterized. The difference in HIV-1 mutation rate between HeLa and CEM-A cells was not significant, indicating that the accuracy of HIV-1 reverse transcription is comparable in both the HeLa and CEM-A cell lines.
先前已开发出一种体内测定法，用于在单个复制周期中检测1型人类免疫缺陷病毒（HIV-1）的正向突变。该系统使用lacZα肽基因作为突变的报告基因，并能够确定发生的突变率和突变类型。发现HIV-1在HeLa细胞中的正向突变率为每个靶碱基对每周期3×10⁻⁵个突变。为了测试突变率是否受细胞类型影响，测定了HIV-1在T淋巴细胞系CEM-A细胞中的突变率。发现HIV-1在CEM-A细胞中的逆转录突变率为每个靶碱基对每周期4×10⁻⁵个突变。观察到的突变数量和类型与HeLa细胞中的相似。具体而言，碱基替换突变占主导，G到A的转换突变是最常见的碱基替换。还对G到A的超突变体进行了表征。HeLa细胞和CEM-A细胞之间HIV-1突变率的差异不显著，表明HIV-1逆转录的准确性在HeLa细胞系和CEM-A细胞系中相当。
