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Tetrameric INTS6-SOSS1 complex facilitates DNA:RNA hybrid autoregulation at double-strand breaks
Qilin Long1, Kamal Ajit1, Katerina Sedova2
1Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
Nucleic Acids Research
|October 24, 2024
Summary
The Integrator complex subunit 6 (INTS6) and SOSS1 complex regulate DNA repair by managing RNA polymerase II activity and resolving DNA:RNA hybrids at double-strand break sites.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- DNA double-strand breaks (DSBs) are critical DNA lesions.
- RNA polymerase II (RNAPII) activity at DSBs is essential for repair.
- Mechanisms regulating transcription at DSBs remain unclear.
Purpose of the Study:
- Investigate the role of Integrator complex subunit 6 (INTS6) in DNA double-strand break repair.
- Elucidate the function of the SOSS1 complex in regulating transcription at DSBs.
- Understand the resolution of DNA:RNA hybrids during DNA repair.
Main Methods:
- Co-immunoprecipitation assays to identify protein interactions.
- Chromatin immunoprecipitation to assess protein binding at DSB sites.
- Biochemical assays to study DNA:RNA hybrid dynamics.
Main Results:
- INTS6 forms a tetrameric complex with SOSS1 (INTS3, INIP, hSSB1).
- INTS6 recruits Protein Phosphatase 2A (PP2A) to DSBs, promoting RNAPII dephosphorylation.
- INTS6 resolves DNA:RNA hybrids/R-loops by recruiting senataxin (SETX) and preventing DARTs accumulation.
Conclusions:
- The tetrameric SOSS1 complex, involving INTS6, plays a crucial role in DNA double-strand break repair.
- INTS6 autoregulates DNA:RNA hybrids, facilitating efficient DSB repair.
- Understanding these mechanisms offers insights into preventing oncogenesis.
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