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DNA break mapping reveals topoisomerase II activity genome-wide.

ABSTRACT: Genomic DNA is under constant assault by endogenous and exogenous DNA damaging agents. DNA breakage can represent a major threat to genome integrity but can also be necessary for genome function. Here we present approaches to map DNA double-strand breaks (DSBs) and single-strand breaks (SSBs) at the genome-wide scale by two methods called DSB- and SSB-Seq, respectively. We tested these methods in human colon cancer cells and validated the results using the Topoisomerase II (Top2)-poisoning agent etoposide (ETO). Our results show that the combination of ETO treatment with break-mapping techniques is a powerful method to elaborate the pattern of Top2 enzymatic activity across the genome.

SUBMITTER: Baranello L

PROVIDER: S-EPMC4139894 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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DNA break mapping reveals topoisomerase II activity genome-wide.

Baranello Laura L Kouzine Fedor F Wojtowicz Damian D Cui Kairong K Przytycka Teresa M TM Zhao Keji K Levens David D

International journal of molecular sciences 20140723 7

Genomic DNA is under constant assault by endogenous and exogenous DNA damaging agents. DNA breakage can represent a major threat to genome integrity but can also be necessary for genome function. Here we present approaches to map DNA double-strand breaks (DSBs) and single-strand breaks (SSBs) at the genome-wide scale by two methods called DSB- and SSB-Seq, respectively. We tested these methods in human colon cancer cells and validated the results using the Topoisomerase II (Top2)-poisoning agent ...[more]

PMID: 25056547

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