The distribution of DNA topoisomerase II isoforms in differentiated adult mouse tissues

J M Juenke1, J A Holden

  • 1Department of Pathology, University of Utah, Salt Lake City 84132.

Antibodies raised against the alpha and beta isoforms of human DNA topoisomerase II were found to react with the corresponding mouse enzymes. By using these antibodies in Western blotting experiments, it was observed that these isoforms are differentially expressed in adult mouse tissues. The alpha isoform is abundant in testis and spleen. The beta isoform is also abundant in spleen and in addition is present in kidney and liver. Type II topoisomerase is low in brain and heart. These results suggest different functions for these two isoforms of DNA topoisomerase II.

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