Participation of Poly(ADP-ribose)-Polymerase of Nuclear Matrix in DNA Repair

T. M. Zaalishvili^*, I. Yu. Gabriadze, D. O. Margiani, V. R. Philauri, and N. M. Surguladze

Institute of Molecular Biology and Biological Physics, Georgian Academy of Sciences, ul. L. Gotua 14, Tbilisi, 380060 Georgia; fax: (8832) 939-157

^* To whom correspondence should be addressed.

Received May 20, 1999; Revision received January 10, 2000

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The poly(ADP-ribose)-polymerase activity of brain and liver cell nuclei is changed during X-irradiation of rats. In the nuclear matrix, poly(ADP-ribose)-polymerase activity increases at a low dose of irradiation (1.7 Gy) and decreases at a high dose (6.7 Gy). A significant part of the activity of nuclear NMN-adenylyltransferase, a key enzyme for biosynthesis of NAD (the substrate of poly(ADP-ribose)-polymerase), has been found in the nuclear matrix. An interrelation between ADP-ribosylation taking place on the matrix level and eukaryotic cell DNA repair is suggested.

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KEY WORDS: DNA, NAD, nuclei, nuclear matrix, poly(ADP-ribose)-polymerase, NMN-adenylyltransferase

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