FIDELITY OF TRANSCRIPTION BY ESCHERICHIA-COLI RIBONUCLEIC-ACID POLYMERASE
FIDELITY OF TRANSCRIPTION BY ESCHERICHIA-COLI RIBONUCLEIC-ACID POLYMERASE
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DOI：
10.1016/s0022-2836(75)80060-x
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发表时间：
1975-01-01
影响因子：
5.6
通讯作者：
LOEB, LA
中科院分区：
文献类型：
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作者：
SPRINGGATE, CF;LOEB, LA
用大肠杆菌RNA聚合酶和合成的多聚脱氧核苷酸模板研究了转录的准确性。用全酶，观察到掺入RNA产物中的非互补碱基与互补碱基的最高比率为：CTP（1：2400）、ATP（1：9000）、UTP（1：20，000）、GTP（1：42，000）。非互补碱基掺入RNA产物的频率不受模板性质的显著影响，但发现主要由非互补核糖核苷酸的类型决定。在平行实验中观察到，核心酶的保真度与全酶的保真度相似。虽然从全酶中去除σ因子对RNA聚合酶的非互补碱基插入没有明显的影响，但观察到向核心酶中添加σ因子在相同程度上刺激了互补和非互补碱基。以poly[d（A-T）]·poly[d（A-T）]为模板，最近邻分析显示CTP总是与模板上的dAMP并置地掺入RNA产物中。因此，由RNA聚合酶催化的最常见的错误可以归类为dA-rU到dA-rC的转变。
The accuracy of transcription has been studied using RNA polymerase fromEscherichia coliand synthetic polydeoxynucleotide templates. With the holoenzyme, the highest ratios of non-complementary to complementary bases incorporated into RNA product were observed to be: CTP (1 to 2400), ATP (1 to 9000), UTP (1 to 20,000), GTP (1 to 42,000). The frequency of non-complementary base incorporation into RNA products was not significantly affected by the nature of the template but was found to be primarily determined by the type of non-complementary ribonucleotide.In parallel experiments it was observed that the fidelity of core enzyme was similar to that of holoenzyme. Although removal of sigma factor from holoenzyme had no appreciable effect on non-complementary base-insertion by RNA polymerase, it was observed that the addition of sigma factor to core enzyme stimulated both complementary and non-complementary bases to an equal extent. With poly[d(A-T)]·poly[d(A-T)] as template, nearest-neighbor analysis revealed that CTP was invariably incorporated into the RNA product in juxtaposition with dAMP on the template. Thus, the most frequent error catalyzed by RNA polymerase may be classified as a transition, dA-rU to dA-rC.