Jackson D A
Sir William Dunn School of Pathology, University of Oxford, UK.
Nucleic Acids Res. 1990 Feb 25;18(4):753-8. doi: 10.1093/nar/18.4.753.
In eukaryotic cells, two enzymes, DNA polymerases alpha and delta, are thought to play major roles in DNA synthesis. I have used butylphenyl dGTP (BuPdGTP), a potent inhibitor of purified DNA polymerase alpha, to assess the relative activities of these enzymes in two permeabilized cell systems. In both instances BuPdGTP eliminated all of the activity which was sensitive to aphidicolin. However, no conditions were found where BuPdGTP preferentially inhibited the synthesis of Okazaki fragments--the presumed products of DNA polymerase alpha activity. This implies that DNA polymerase activities on the two sides of the replication fork are unable to operate independently, being just two elements of the integrated replication machinery that undertakes DNA synthesis in permeabilized cells.
在真核细胞中,两种酶,即DNA聚合酶α和δ,被认为在DNA合成中起主要作用。我使用了丁基苯基dGTP(BuPdGTP),一种纯化的DNA聚合酶α的有效抑制剂,来评估这两种酶在两种通透细胞系统中的相对活性。在这两种情况下,BuPdGTP消除了所有对阿非迪霉素敏感的活性。然而,没有发现BuPdGTP优先抑制冈崎片段合成的条件——冈崎片段被认为是DNA聚合酶α活性的产物。这意味着复制叉两侧的DNA聚合酶活性不能独立运作,它们只是通透细胞中进行DNA合成的整合复制机制的两个组成部分。