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USP7 regulates the stability and function of HLTF through deubiquitination
1Department of Respiratory Diseases, Minhang District Central Hospital, Shanghai, P.R. China.
Journal of Cellular Biochemistry
|August 17, 2011
Summary
Ubiquitin-specific protease 7 (USP7) stabilizes human helicase-like transcription factor (HLTF), enhancing DNA repair. This USP7-HLTF pathway is crucial for genomic stability and cellular resistance to DNA damage.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Human helicase-like transcription factor (HLTF) is vital for error-free DNA replication and genomic stability.
- HLTF facilitates the polyubiquitination of proliferating cell nuclear antigen (PCNA), a key process in DNA damage tolerance.
Purpose of the Study:
- To identify novel regulators of HLTF stability.
- To elucidate the role of ubiquitin-specific protease 7 (USP7) in the DNA damage response pathway involving HLTF and PCNA.
Main Methods:
- Co-immunoprecipitation assays to detect protein interactions.
- Western blotting to assess protein levels and ubiquitination status.
- Cell viability assays to determine sensitivity to genotoxic stress.
Main Results:
- USP7 directly interacts with and stabilizes HLTF following genotoxic stress.
- USP7-mediated deubiquitination of HLTF significantly increases its half-life.
- USP7 inhibition enhances cellular sensitivity to DNA damage, while HLTF overexpression can rescue this effect.
Conclusions:
- USP7 is a novel deubiquitylating enzyme that positively regulates HLTF stability and function.
- A previously unrecognized USP7-HLTF-PCNA molecular network is identified, playing a critical role in the DNA damage response.
- Targeting USP7 could represent a therapeutic strategy for enhancing cancer treatment efficacy by impairing DNA repair mechanisms.
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