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Topological linkage of circular DNA molecules promoted by Ustilago rec 1 protein and topoisomerase.

TitleTopological linkage of circular DNA molecules promoted by Ustilago rec 1 protein and topoisomerase.
Publication TypeJournal Article
Year of Publication1983
AuthorsKmiec EB, Kroeger PE, Brougham MJ, Holloman WK
Date Published1983 Oct
KeywordsAdenosine Triphosphate, Adenylyl Imidodiphosphate, Basidiomycota, DNA Topoisomerases, Type I, DNA, Circular, Exodeoxyribonuclease V, Fungal Proteins, Genetic Linkage, Nucleic Acid Conformation, Ustilago

We studied the formation of linked circular DNA molecules promoted by the combined action of rec 1 protein and type I topoisomerase of Ustilago maydis. When ATP was added as cofactor to reactions containing rec 1 protein, pairs of homologous circular DNA molecules became linked after addition of topoisomerase. Closed circular duplex molecules could be joined at homologous sites with circular single-stranded molecules or with other circular duplex molecules, provided that homologous single-stranded DNA fragments or RNA polymerase and nucleoside triphosphates were also added. Complexes formed were topologically linked through regions of heteroduplex DNA. When the analog adenylyl-imidodiphosphate was substituted for ATP, nonhomologous pairs of circular DNA molecules became linked.

Alternate JournalCell
PubMed ID6313215
Grant ListGM 27103 / GM / NIGMS NIH HHS / United States

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