Base long-patch

Dianov, G. L., Prasad, R., Wilson, S. H., and Bohr, V. A. 1999. Role of DNA polymerase /3 in the excision step of long patch mammalian base excision repair. 7. Biol. Chem. 274 13741-13743. 

Fortini P, DogUotti E. Base damage and single-strand break repair mechanisms and functional significance of short- and long-patch repair subpathways. DNA Repair 2007 6 398-409. 

Dianov GL, Bischoff C, Piotrowski J, Bohr VA (1998) Repair pathways for processing of 8-oxoguanine in DNA by mammalian cell extract J Biol Chem 273 33811-6 Fortini P, Pascucci B, Parlanti E, Sobol RW, Wilson SH, Dogliotti E (1998) Different DNA polymerases are involved in the short- and long-patch base excision repair in mammalian. Biochemistry 37 3575-80... 

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. 

Dianova, 1. L, Bohr, V. A., and Dianov, G. L. (2001). Interaction of human AP endonuclease 1 with flap endonuclease 1 and proliferating cell nuclear antigen involved in long-patch base excision repair. Biochemistry 40, 12639-12644. 

Parker, A., Gu, Y., Mahoney, W., Lee, S. H., Singh, K, K, and Lu, A. L. (2001). Human homolog of the MutY repair protein (hMYH) physically interacts with proteins involved in long patch DNA base excision repair. J. BioL Chem. 276, 5547—5555. 

Prasad, R., Lavrik, O. I., Kim, S. J., Kedar, P., Yang, X. P., Vande Berg, B. J., and Wilson, S. H. (2001). DNA polymerase beta-mediated long patch base excision repair. Poly(ADP-ribose) polymerase-1 stimulates strand displacement DNA synthesis. 

Based on the close proximity of the two types of hot spot motifs, it is possible that AID-catalyzed deamination of G residues in WRG could therefore provide a mechanism for loading an EP pol to copy nearby WA motifs. Gonversion of G —> U by AID, followed by U removal by UNG + APE enzymes, results in a nick at the 5 -end of the abasic moiety. If an error-prone repair polymerase (e.g., pol rf) binds and carries out strand displacement synthesis (long-patch BER), then misincorporation of G opposite T (Fig. 3) will yield A —> G transitions in the nontranscribed strand at WA hotspots, in accordance with pol r/ s mutational specificity (Pavlov et al, 2002), as shown (in red) in Fig. 3. 

Dianova II, Bohr VA, Dianov GL. Interaction of human AP endonudease 1 with flap endonu-dease 1 and proliferating cell nudear antigen involved in long-patch base exdsion repair. Biochemistry 2001 40 12639-12644. 

Guan L, Bebenek K, Kunkel TA, Greenberg MM. Inhibition of short patch and long patch base excision repab by an oxidized abasic site. Biochemistry. 2010 49 9904-9910. 

Jacobs AC, Kreller CR, Greenberg MM. Long patch base excision repab compensates for DNA polymerase 3 inactivation by the C4 -oxidized abasic site. Biochemistry. 2011 50 136-143. 

Fig. 1. Schematic representation of base excision repair (BER) mechanism. BER consists of two main pathways, short patch repair(left) and long patch repair (right). The first step of BER involves recognition, base removal and incision. The choice between short-patch BER or long-patch BER depends on the state of the 5 deoxyribose phosphate (5 dRP) terminus.

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