Resolution of Converging Replication Forks by RecQ and Topoisomerase III
نویسندگان
چکیده
منابع مشابه
RecQ helicase stimulates both DNA catenation and changes in DNA topology by topoisomerase III.
Together, RecQ helicase and topoisomerase III (Topo III) of Escherichia coli comprise a potent DNA strand passage activity that can catenate covalently closed DNA (Harmon, F. G., DiGate, R. J., and Kowalczykowski, S. C. (1999) Mol. Cell 3, 611-620). Here we directly assessed the structure of the catenated DNA species formed by RecQ helicase and Topo III using atomic force microscopy. The images...
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Camptothecin, which induces an unusual type of DNA damage by trapping cellular topoisomerase I on chromosomal DNA in the form of drug-enzyme-DNA cleavable complexes, inhibits DNA synthesis and specifically kills S-phase cells. Cotreatment of L1210 cells with aphidicolin, which is an inhibitor of replicative DNA polymerases, completely abolished camptothecin cytotoxicity, suggesting the involvem...
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ژورنال
عنوان ژورنال: Molecular Cell
سال: 2008
ISSN: 1097-2765
DOI: 10.1016/j.molcel.2008.04.020