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PubMed · 9354424

A precise interchromosomal reciprocal exchange between hot spots for cleavable complex formation by topoisomerase II in amsacrine-treated Chinese hamster ovary cells.

R H Zhou·P Wang·Y Zou·C K Jackson-Cook·L F Povirk
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Abstract

Among the aprt mutations induced in confluence-arrested Chinese hamster ovary D422 cells by the topoisomerase II poison amsacrine, there was a reciprocal exchange between the aprt gene and an unrelated sequence, accompanied by a chromosomal translocation at the aprt locus. The breakpoints in both parental sequences were hot spots for amsacrine-stimulated DNA cleavage in vitro, and the novel junctions formed were precisely as expected for a mechanism involving reciprocal exchange of topoisomerase II subunits followed by resealing of the breaks and correction of mismatches in the cohesive ends. The results are consistent with a role for direct subunit exchange in the production of chromosomal translocations by topoisomerase poisons, although more complex models involving double-strand breakage and repair could produce reciprocal exchanges of similar specificity.

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Adenine PhosphoribosyltransferaseAmsacrineAnimalsAntineoplastic AgentsBase SequenceCHO CellsChromosome MappingCricetinaeDNA Topoisomerases, Type IIGene RearrangementMolecular Sequence DataSequence DeletionTranslocation, GeneticJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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R H Zhou, P Wang, Y Zou, C K Jackson-Cook, L F Povirk. 1997-11-01. A precise interchromosomal reciprocal exchange between hot spots for cleavable complex formation by topoisomerase II in amsacrine-treated Chinese hamster ovary cells.. https://pubmed.ncbi.nlm.nih.gov/9354424/

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