Translator Disclaimer
1 November 2004 Radiation Affects Binding of Fpg Repair Protein to an Abasic Site Containing DNA
Nathalie Gillard, Marie Begusova, Bertrand Castaing, Melanie Spotheim-Maurizot
Author Affiliations +
Abstract

Gillard, N., Begusova, M., Castaing, B. and Spotheim-Maurizot, M. Radiation Affects Binding of Fpg Repair Protein to an Abasic Site Containing DNA. Radiat. Res. 162, 566– 571 (2004).

During the base excision repair of certain DNA lesions, the formamidopyrimidine-DNA glycosylase (Fpg) binds specifically to the DNA region containing an abasic (AP) site. Is this step affected by exposure to ionizing radiation? To answer this question, we studied a complex between a DNA duplex containing an analogue of an abasic site (the 1,3-propanediol site, Pr) and a mutated Lactococcus lactis Fpg (P1G-LlFpg) lacking strand cleavage activity. Upon irradiation of the complex, the ratio of bound/free partners decreased. When the partners were irradiated separately, the irradiated DNA still bound the unirradiated protein, whereas irradiated Fpg no longer bound unirradiated DNA. Thus irradiation hinders Fpg-DNA binding because of the damage to the protein. Using our radiolytic attack simulation procedure RADACK (Begusova et al., J. Biomol. Struct. Dyn. 19, 141–157, 2001), we reveal the potential hot spots for damage in the irradiated protein. Most of them are essential for the interaction of Fpg with DNA, which explains the radiation-induced loss of binding ability of Fpg. The doses necessary to destroy the complex are higher than those inactivating Fpg irradiated separately. As confirmed by our calculations, this can be explained by the partial protection of the protein by the bound DNA.

Nathalie Gillard, Marie Begusova, Bertrand Castaing, and Melanie Spotheim-Maurizot "Radiation Affects Binding of Fpg Repair Protein to an Abasic Site Containing DNA," Radiation Research 162(5), 566-571, (1 November 2004). https://doi.org/10.1667/RR3247
Received: 26 March 2004; Accepted: 1 May 2004; Published: 1 November 2004
JOURNAL ARTICLE
6 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top