2017  0,977
2016  0,799
2015  0,662
2014  0,740
2013  0,739
2012  0,637
2011  0,658
2010  0,654
2009  0,570
2008  0,849
2007  0,805
2006  0,330
2005  0,435
2004  0,623
2003  0,567
2002  0,641
2001  0,490
2000  0,477
1999  0,762
1998  0,785
1997  0,507
1996  0,518
1995  0,502
Vol 52(2018) N 2 p. 237-246; DOI 10.1134/S0026893318020061 Full Text

N.V. Lukyanchikova1, I.O. Petruseva1*, A.N. Evdokimov1, L.S. Koroleva1, O.I. Lavrik1,2,3**

DNA Bearing Bulky Fluorescent and Photoreactive Damage in Both Strands as Substrates of the Nucleotide Excision Repair System

1Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090 Russia
2Novosibirsk State University, Novosibirsk, 630090 Russia
3Altai State University, Barnaul, 656049 Russia

Received - 2016-11-22; Accepted - 2017-01-28

Model DNA molecules that contain bulky lesions in both strands have been created, and their properties as substrates of the nucleotide excision repair (NER) system have been analyzed. The modified nucleoside, 5-[3-(4-azido-2,3,5,6-tetrafluorobenzamido)-1-propoxypropyl]-2'-deoxycytidine (dCFAB), or the nonnucleoside fragment, N-[6-(9-anthracenylcarbamoyl)hexanoyl]-3-amino-1,2-propanediol (nAnt), have been inserted as damage in certain positions of the first DNA strand ("0"). The position of N-[6-5(6)-fluoresceinylcarbamoyl]hexanoyl] -3-amino-1,2-propanediol (nFlu) has been varied within the second DNA strand. This residue has been located opposite the removable damaging fragment of the first strand at positions -20, -10, -4, 0, +3, and +8 relative to the first lesion. It has been demonstrated that the presence of nFlu at the -4, 0, or +3 position of the second strand significantly reduces the thermostability of DNA duplexes, especially in the case of nAnt-DNA and completely excludes the possibility of NER-catalyzed excision from dCFAB- and nAnt-containing 137-meric DNA with the second lesion at these positions. The introduction of nFlu at positions -20, -10, or +8 differently affects the excision efficiency of dCFAB- and nAnt-containing fragments from the first strand. The excision efficiency of dCFAB-containing fragments from extended double-damaged DNA is as high as from DNA that contains a single dCFAB damage, while the excision of nAnt-containing fragments occurs with 80-90% lower efficiency from double-damaged DNA occurs from DNA that contains the single nAnt insert. The nFlu insert differently affects the interaction of the sensory XPC-HR23B dimer with dCFAB- and nAnt-containing DNAs, although in all cases, this interaction occurs with increased efficiency compared to that with single-damaged DNAs. No direct correlation between the thermostability of the DNA duplex and XPC-DNA affinity on the one hand, and the excision efficiency of lesions on the other hand has been shown. The absence of the correlation may be caused by both functional features of variable multiprotein complexes involved in the recognition and verification of damage during NER and the sensitivity of the complexes to the structure of the damage and damage-surrounding DNA. The results are important for understanding the NER mechanism of elimination of bulky damage located in both DNA strands.

nucleotide excision repair, higher eukaryotes, DNA substrates, multiple DNA lesions