DNA helicase E and DNA polymerase epsilon functionally interact for displacement synthesis.
DNA helicase E and DNA polymerase epsilon functionally interact for displacement synthesis.
复制标题
DNA 解旋酶 E 和 DNA 聚合酶 epsilon 在功能上相互作用以进行置换合成。
DOI：
10.1021/bi00152a043
复制
发表时间：
1992
期刊：
影响因子：
2.9
通讯作者：
Bambara,RA
中科院分区：
文献类型：
--
作者：
Turchi,JJ;Siegal,G;Bambara,RA
Revised Manuscript Received June 5, 1992 abstract: A functional interaction between DNA helicase E and DNA polymerase e from calf thymus has been detected which results in the extension of an upstream V OH through a downstream primer to the end of a synthetic template. DNA synthesis resulting in full-length extension products was dependent on the addition of DNA helicase E and hydrolysis of ATP, suggesting that displacement of the downstream primer was required. Identical reactions using DNA polymerases a and 5 in place of DNA polymerase «showed no full-length products dependent on helicase E, indicating that polymerases a and S were incapable of functionally interacting with the helicase. The reaction leading to full-length extension products was time dependent and dependent on the concentration of added polymerase e and helicase E. Exonucleolytic degradation of the downstream primer, or ligation of the downstream primer to the upstream 3'OH, were not responsible for the full-length products observed. Displacement of the downstream primer by DNA helicase E was not affected by the addition of polymerase€ to the reactions. Templatedilution experiments demonstrated that DNA polymerase e and helicase E were acting in concert to perform displacement synthesis. Additional evidence for functional coordination was obtained by demonstration that DNA helicase E stimulated DNA polymerase e in a standard DNA synthetic assay using dA3ooo-dTi6 as the templateprimer. The resultspresented are consistent with the hypothesis that DNA helicase E and DNA polymerase e are capable of coordinated activities that result in displacement synthesis. A functionalinteraction of this sort may be involved at the eukaryotic replication fork or in DNA repair.DNA helicases are required in many facets of DNA and RNA metabolism including replication, repair, recombination, and termination of transcription (Thommes & Hubscher, 1990a; Matson, 1991; Matson & Kaiser-Rogers, 1990). Eukaryotic chromosomal DNA replication requires a helicase activity at each replication fork to separate the duplex DNA strands prior to their replication. Thisyet unidentified eukaryotic helicase presumably interacts with the DNA polymerases responsible for DNA replication. It has recently been demonstrated in yeast that DNA polymerase a (pol a) 1 (Johnson et al., 1985), pol 5 (Boulet et al., 1989), and pol e (Morrison et al., 1990) are each encoded by separate genes, all of which are required for viability. Deletionmutants constructed for each DNA polymerase arrest in early S phase,
