Topoisomerase II (TOP2) relieves torsional stress by forming transient cleavage complex intermediates (TOP2ccs) that contain TOP2-linked DNA breaks (DSBs). While TOP2ccs are normally reversible, they can be "trapped" by chemotherapeutic drugs such as etoposide and subsequently converted into irreversible TOP2-linked DSBs. Here, we have quantified etoposide-induced trapping of TOP2ccs, their conversion into irreversible TOP2-linked DSBs, and their processing during DNA repair genome-wide, as a function of time. We find that while TOP2 chromatin localization and trapping is independent of transcription, it requires pre-existing binding of cohesin to DNA. In contrast, the conversion of trapped TOP2ccs to irreversible DSBs during DNA repair is accelerated 2-fold at transcribed loci relative to non-transcribed loci. This conversion is dependent on proteasomal degradation and TDP2 phosphodiesterase activity. Quantitative modeling shows that only two features of pre-existing chromatin structure-namely, cohesin binding and transcriptional activity-can be used to predict the kinetics of TOP2-induced DSBs.
- Klíčová slova
- 3D chromatin organization, DNA double-strand breaks, TDP2, chromosomal translocations, cohesin, proteasome, quantitative modeling, topoisomerase, topoisomerase 2 cleavage complex, transcription,
- MeSH
- chromozomy genetika MeSH
- DNA vazebné proteiny chemie genetika MeSH
- DNA-topoisomerasy typu II chemie genetika MeSH
- DNA chemie genetika MeSH
- dvouřetězcové zlomy DNA * MeSH
- etoposid chemie MeSH
- genetická transkripce MeSH
- genová konverze genetika MeSH
- HCT116 buňky MeSH
- inhibitory topoisomerasy II chemie farmakologie MeSH
- kinetika MeSH
- lidé MeSH
- multiproteinové komplexy chemie genetika MeSH
- oprava DNA genetika MeSH
- proteiny vázající poly-ADP-ribosu chemie genetika MeSH
- torze mechanická MeSH
- translokace genetická genetika MeSH
- zlomy chromozomů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Intramural MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Názvy látek
- DNA vazebné proteiny MeSH
- DNA-topoisomerasy typu II MeSH
- DNA MeSH
- etoposid MeSH
- inhibitory topoisomerasy II MeSH
- multiproteinové komplexy MeSH
- proteiny vázající poly-ADP-ribosu MeSH
- TOP2A protein, human MeSH Prohlížeč
