DNA polymerase epsilon

Nucleotide-excision repair involves PCNA, DNA polymerase epsilon, and several accessory proteins, such as RF-C (replication factor C), RP-A (replication protein A), and Lig I (DNA ligase I). It could be that these proteins form an aggregate DNA repair machine. PCNA is a hollow circular protein that encircles DNA. PCNA binds and activates many proteins involved in DNA repair. Mismatch repair is less well characterized, but involves DNA polymerase delta. 

Dua, R., Levy, D. L., and Campbell, J. L. (1998). Role of the putative zinc finger domain of Saccharomyces cerevisiae DNA polymerase epsilon in DNA replication and the S/M checkpoint pathway. J. Biol. Chem. 273, 30046-30055. 

Fuss, J., and Linn, S. (2002). Human DNA polymerase epsilon colocalizes with proliferating cell nuclear antigen and DNA replication late, but not early, in S phase. J. Biol. Chem. 277, 8658-8666. 

Kesti, T., Flick, K., Keranen, S., Syvaoja, J. E., and Wittenberg, C. (1999). DNA polymerase epsilon catalytic domains are dispensable for DNA replication, DNA repair, and cell viabUily. Mol. Cell 3, 679-685. 

Navas, T. A., Sanchez, Y., and Elledge, S. J. (1996). RAD9 and DNA polymerase epsilon form parallel sensory branches for transducing the DNA damage checkpoint signal in Saccharomyces cerevisiae. Genes Dev. 10, 2632-2643. 

Shcherbakova, P. V., and Pavlov, Y. I. (1996). 3 —>5 exonucleases of DNA polymerases epsilon and delta correct base analog induced DNA replication errors on opposite DNA strands in Saccharomyces cerevisiae. Genetics 142, 717-726. 

Wang, Z., Wu, X., and Friedberg, E. C. (1993). DNA repair synthesis during base excision repair in vitro is catalyzed by DNA polymerase epsilon and is influenced... 

Edwards S, Li CM, Levy DL, Brown J, Snow PM, Campbell JL (2003)Saccharvmyces cere-visiae DNA polymerase epsilon and polymerase sigma interact physically and functionally, suggesting a role for polymerase epsilon in sister ehromatid cohesion. Mol Cell Biol 23(8) 2733-2748... 

DNA polymerase III is much more complex than DNA polymerase I, having ten types of subunits (Table 25-2). Its polymerization and proofreading activities reside in its a and e (epsilon) subunits, respectively. The 6 subunit associates with a and e to form a core polymerase, which can polymerize DNA but with limited processivity. Two core polymerases can be linked by... 

TWn relatively recent developments have added to our knowledge significantly concerning how DNA replication occurs with fidelity or in what molecular biologists and biochemists call a processive polymerase activity. DNA polymerase is the enzyme which actually polymerizes (adds DNA precursors or building blocks) DNA. There are many such DNA polymerases in pro- and eukaryotic cells that have different functions but the main enzyme in prokaryotes is DNA polymerase 111 and in Eukaryotes. DNA polymerases alpha, delta, and epsilon. All four of these DNA polymerases are made of subunits. 

Available evidence indicates that PCNA is also involved in DNA nucleotide excision-repair. This role is exemplified by the demonstration that PCNA can be found associated with chromatin at all phases of the cell cycle after ultraviolet irradiation in vitro (Toschi and Bravo, 1988). Recently it was shown that not only DNA polymerase delta but DNA polymerases beta and epsilon are also involved in the base excision repair subpathways (Dianov et al., 1999). In addition, PCNA may be expressed by noncycling cells in vivo which are undergoing DNA repair (Hall et al., 1993). 

Pascucci, B., Stucki, M., Jonsson, Z.O., Dogliotti, E., and Htibscher, U. (1999) Long patch base excision repair with purified human proteins. DNA ligase I as patch size mediator for DNA polymerases delta and epsilon. 

Keniry MA, Park AY et al (2006) Stmcture of the theta subunit of Escherichia coli DNA polymerase III in complex with the epsilon subunit. J Bacteriol 188(12) 4464-4473... 

Wang, S. W., Toda, T., MacCallum, R., Harris, A. L., and Norbury, C. (2000a). Cidl, a fission yeast protein required for S-M checkpoint control when DNA polymerase delta or epsilon is inactivated. Mol Cell Biol. 20, 3234—3244. 

Birkus G, Rejman D, Otmar M, Votruba I, Rosenberg I, Holy A (2004) The substrate activity of (S)-9-[3-hydroxy-(2-phosphonomethoxy)propyl]adenine diphosphate toward DNA polymerases alpha, delta and epsilon. Antivir Chem Chemother 15 23-33 Magee WC, Valiaeva N, Beadle JR, Richman DD, Hostetler KY, Evans DH (2011) Antimicrob Agents Chemother 55(ll) 5063-5072... 

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