Biopolym. Cell. 1993; 9(6):52-59.
 Structure and Function of Biopolymers
Fractionation of eukaryotic DNA by pulsed field gel electrophoresis. The peculiarities of topoisomerase / DNA complex behaviour in 
isolated nuclei
- Institute of Molecular Biology and Genetics, NAS of Ukraine
 150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680
Abstract
The properties of topoisomerase II/DNA complex in nuclear preparations have been investigated. It has been shown that topoII/nuclear DNA complex functiones unitypically both in Mg2+- and in Ca2+-containing media. Unlike to the in vitro assay the treatment of topoII/nuclear DNA complex with EDTA resulted in increase of nuclear DNA cleavage rather than its rejoining. The nuclear topoII/DNA complex treated with SDS was found to acquire the capacity to subsequent SDS-independent nuclear DNA cleavage. The salient features of topoisomerase II/nuclear DNA complex are supposed to be due to the topoII enzyme involvement in higher level's chromatin compactization leading to the initial stabilization of topoII/nuclear DNA complex in vivo conditions. The availability in cells the different topoII/DNA complex variants of possible physiological value has been proposed.
Full text:  (PDF, in Russian)
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