Nucleotide excision repair dual incisions

The mechanism of eukaryotic excinucleases is quite similar to that of the bacterial enzyme, although 16 polypeptides with no similarity to the E. coli excinuclease subunits are required for the dual incision. As described in Chapter 26, some of the nucleotide-excision repair and base-excision repair in eukaryotes is closely tied to transcription. Genetic deficiencies in nucleotide-excision repair in humans give rise to a variety of serious diseases (Box 25-1). 

Figure 6 Nucleotide excision repair in (A) E. coli and (B) humans. There are five basic steps of nucieotide excision repair (1) damage recognition, (2) dual incisions, (3) release of the excised oligomer, (4) repair synthesis to fill in the gap, and (5) ligation.

Evans E,Moggs JG, Hwang JR,EglyJM,Wood RD (1997) Mechanism of open complex and dual incision formation by human nucleotide excision repair factors. EMBO J 16 6559-73... 

Wakasugi, M., Reardon, J.T., and Sancar, A. (1997) The non-catalytic function of XPG protein during dual incision in human nucleotide excision repair./. Biol. Chem., 272,16030-16034. 

J. H., Gourdin, A.M., Wijgers, N., Dunand-Sauthier, I., Giglia-Mari, G., Clarkson, S.G., Vermeulen, W., and Scharer, O.D. (2009) Coordination of dual incision and repair synthesis in human nucleotide excision repair. EMBOJ., 28, 1111-1120. 

Y., Rodriguez, F., Kolbanovskii, A., Liu, Y., Zhang, L., Amin, S., Patel, D., Broyde, S., et al. (2009) The sequence dependence of human nucleotide excision repair efficiencies of benzoja] pyrene-derived DNA lesions insights into the structural factors that favor dual incisions. J. Mol. Biol., 386, 1193-1203. 

Fig. 1. Schematic illustration of nucleotide excision repair in prokaryotes and eukaryotes. The basic steps are conserved damage recognition and dual incisions to excise DNA damage, helicase activity to displace excised oligomer and repair factors, and resynthesis/ligation to restore the integrity of the DNA molecule. (See Color Insert.)...

Bessho, T., Mu, D., and Sancar, A. (1997). Initiation of DNA interstrand cross-link repair in humans The nucleotide excision repair system makes dual incisions 5 to the cross-linked base and removes a 22- to 28-nucleotide long damage free strand. 

Egly,J.-M. (2001). TFIIH From transcription to clinic. FEES Lett. 24884, 124-128. Evans, E., Moggs,J. G., Hwang, J. R., Egly,J.-M., and Wood, R. D. (1997). Mechanism of open complex and dual incision formation by human nucleotide excision repair factors. EMBOJ. 16, 6559-6573. 

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