Nucleic Acids Research, 2012, Vol. 40, No. 16 7931 activity residing within the mitochondrial matrix. Nucleic Acids Res., 31, 1364–1373. 121. Ikeda,S. and Ozaki,K. (1997) Action of mitochondrial endonuclease G on DNA damaged by L-ascorbic acid, peplomycin, and cis-diamminedichloroplatinum (II). Biochem. Biophys. Res. Commun., 235, 291–294. 122. Shokolenko,I., Venediktova,N., Bochkareva,A., Wilson,G.L. and Alexeyev,M.F. (2009) Oxidative stress induces degradation of mitochondrial DNA. Nucleic Acids Res., 37, 2539–2548. 123. Tann,A.W., Boldogh,I., Meiss,G., Qian,W., Van Houten,B., Mitra,S. and Szczesny,B. (2011) Apoptosis induced by persistent single-strand breaks in mitochondrial genome: critical role of EXOG (5’-EXO/endonuclease) in their repair. J. Biol. Chem., 286, 31975–31983. 124. Brooks,P.J. (2007) The case for 8,5’-cyclopurine-2’- deoxynucleosides as endogenous DNA lesions that cause neurodegeneration in xeroderma pigmentosum. Neuroscience, 145, 1407–1417. 125. Jeong,Y.C., Nakamura,J., Upton,P.B. and Swenberg,J.A. (2005) Pyrimido[1,2-a]-purin-10(3H)-one, M1G, is less prone to artifact than base oxidation. Nucleic Acids Res., 33, 6426–6434.