Fidelity of two retroviral reverse transcriptases during DNA-dependent DNA synthesis in vitro
Fidelity of two retroviral reverse transcriptases during DNA-dependent DNA synthesis in vitro
复制标题
体外 DNA 依赖性 DNA 合成过程中两种逆转录病毒逆转录酶的保真度
DOI：
--
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发表时间：
1989
影响因子：
5.3
通讯作者：
'. Kunkel
中科院分区：
文献类型：
--
作者：
D. John;Roberts;Bradley D. Preston;Laura A. Johnston;Aruna;Soni;Lawrence A. Loeb;A. Thomas;'. Kunkel
我们以M13mp2 LacZα基因为突变靶点，测定了禽成髓细胞增多症病毒和Moloney鼠白血病病毒逆转录酶(RTS)在体外DNA合成过程中的保真度。这两个RT大约每聚合30,000个核苷酸就会出错一次。对正向突变试验中产生的突变体进行的DNA序列分析表明，禽成髓细胞增多症病毒RT产生了各种不同的突变。大多数(58%)是单碱基替换；所有这些都是由于DAMP或dGMP的错误结合造成的。-1移码也很常见，约占突变的30%。除了单碱基事件，8个突变体还包含2到59个碱基的序列变化。这些突变体的频率表明，至少在DNA体外合成过程中，RTS也会因为经典的碱基错误编码和错位以外的机制而出错。我们检测了RTS从错配的引物末端合成DNA的能力，该序列中错配的碱基与模板中的下一个碱基互补。与细胞DNA聚合酶从不匹配的模板-引物聚合不同，RTS更喜欢从重新排列的模板-引物聚合，模板链中包含匹配的末端碱基对和未配对的碱基。对这种底物的不同寻常的偏好表明，RTS和模板-引物之间的相互作用不同于细胞DNA聚合酶。体外RT的总体错误率足以解释这些病毒的估计突变率。
We determined the fidelity of avian myeloblastosis virus and Moloney murine leukemia virus reverse transcriptases (RTs) during DNA synthesis in vitro using the M13mp2 lacZ alpha gene as a mutational target. Both RTs commit an error approximately once for every 30,000 nucleotides polymerized. DNA sequence analysis of mutants generated in a forward mutation assay capable of detecting many types of errors demonstrated that avian myeloblastosis virus RT produced a variety of different mutations. The majority (58%) were single-base substitutions; all of which resulted from the misincorporation of either dAMP or dGMP. Minus-one frameshifts were also common, composing about 30% of the mutations. In addition to single-base events, eight mutants contained sequence changes involving from 2 to 59 bases. The frequency of these mutants suggests that, at least during DNA synthesis in vitro, RTs also commit errors by mechanisms other than classical base miscoding and misalignment. We examined the ability of RTs to synthesize DNA from a mismatched primer terminus at a sequence where the mismatched base was complementary to the next base in the template. Unlike cellular DNA polymerases which polymerize from the mismatched template-primer, RTs preferred to polymerize from a rearranged template-primer containing a matched terminal base pair and an unpaired base in the template strand. The unusual preference for this substrate suggests that the interactions between RTs and the template-primer are different from those of cellular DNA polymerases. The overall error rate of RT in vitro is sufficient to account for the estimated mutation rate of these viruses.
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莫洛尼鼠白血病病毒逆转录酶的结构域：突变分析以及 DNA 聚合酶和 RNase H 活性的单独表达。
DOI：
10.1073/pnas.85.6.1777
发表时间：
1988
影响因子：
11.1
作者：
Tanese,N;Goff,SP
通讯作者：
Goff,SP
来自果蝇胚胎的 DNA 聚合酶引物酶。
DOI：
--
发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kaguni,LS;DiFrancesco,RA;Lehman,IR
通讯作者：
Lehman,IR
DOI：
10.1016/s0021-9258(19)69623-7
发表时间：
1981-04
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
C. Kane;S. Linn
通讯作者：
C. Kane;S. Linn
影响因子：
2.9
作者：
KUNKEL, TA;SCHAAPER, RM;LOEB, LA
通讯作者：
LOEB, LA
影响因子：
56.9
作者：
HAHN, BH;SHAW, GM;PARKS, WP
通讯作者：
PARKS, WP