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. 1983 Feb 25;11(4):1059-75.
doi: 10.1093/nar/11.4.1059.

DNA topoisomerases from rat liver: physiological variations

M Duguet, C Lavenot, F Harper, G Mirambeau, A M De Recondo
Free PMC article

DNA topoisomerases from rat liver: physiological variations

M Duguet et al. Nucleic Acids Res. .
Free PMC article

Abstract

Besides the nicking-closing (topoisomerase I) activity, an ATP-dependent DNA topoisomerase is present in rat liver nuclei. The enzyme, partially purified, is able to catenate in vitro closed DNA circles in a magnesium-dependent, ATP-dependent, histone H1-dependent reaction, and to decatenate in vitro kinetoplast DNA networks to yield free minicircles in a magnesium-dependent and ATP-dependent reaction. It is largely similar to other eukaryotic type II topoisomerases in its requirements, and presumably belongs to this class of enzymes. Type I and type II activities were measured in rat liver nuclei as a function of regenerating time after partial hepatectomy: type I activity was not significantly changed during this process. In contrast, type II activity was considerably increased, suggesting a possible involvement of the enzyme in DNA replication.

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References

    1. J Biol Chem. 1981 May 25;256(10):4805-9 - PubMed
    1. J Biol Chem. 1981 Jun 10;256(11):5860-5 - PubMed
    1. Proc Natl Acad Sci U S A. 1981 May;78(5):2747-51 - PubMed
    1. Proc Natl Acad Sci U S A. 1981 May;78(5):2883-7 - PubMed
    1. J Biol Chem. 1981 Sep 10;256(17):9334-9 - PubMed

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