EXO5-DNA structure and BLM interactions direct DNA resection critical for ATR-dependent replication restart
| Autor: | Raj K. Pandita, Rajesh Kumar, Tej K. Pandita, Walter J. Chazin, Katharina Schlacher, Albino Bacolla, Shashank Hambarde, Vijay Charaka, Paul Russell, Anirban Maitra, Susan E. Tsutakawa, Chi Lin Tsai, Remy Le Meur, Oliver Limbo, Clayton R. Hunt, John A. Tainer |
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| Rok vydání: | 2021 |
| Předmět: |
Exonucleases
DNA Repair DNA Mutational Analysis Mutant Ataxia Telangiectasia Mutated Proteins medicine.disease_cause Medical and Health Sciences chemistry.chemical_compound 0302 clinical medicine Phosphorylation tumor proliferation 0303 health sciences Mutation Tumor RecQ Helicases Kinase interstrand crosslink repair genetic instability Biological Sciences Up-Regulation Cell biology DNA-Binding Proteins sister chromatid exchange Bloom DNA Replication Exonuclease exonuclease replication stress Biology Article Genomic Instability Cell Line 03 medical and health sciences Cell Line Tumor Genetics medicine Humans fork restart Molecular Biology 030304 developmental biology Nuclease Human Genome DNA Helicases SCE Helicase DNA Oncogenes Cell Biology DNA Replication Fork HEK293 Cells chemistry Hela Cells Fanconi anemia biology.protein Generic health relevance ATR phosphorylation 030217 neurology & neurosurgery HeLa Cells DNA Damage Developmental Biology |
| Zdroj: | Molecular cell, vol 81, iss 14 Mol Cell |
| ISSN: | 1097-2765 |
| Popis: | Stalled DNA replication fork restart after stress as orchestrated by ATR kinase, BLM helicase, and structure-specific nucleases enables replication, cell survival, and genome stability. Here we unveil human exonuclease V (EXO5) as an ATR-regulated DNA structure-specific nuclease and BLM partner for replication fork restart. We find that elevated EXO5 in tumors correlates with increased mutation loads and poor patient survival, suggesting that EXO5 upregulation has oncogenic potential. Structural, mechanistic, and mutational analyses of EXO5 and EXO5-DNA complexes reveal a single-stranded DNA binding channel with an adjacent ATR phosphorylation motif (T88Q89) that regulates EXO5 nuclease activity and BLM binding identified by mass spectrometric analysis. EXO5 phospho-mimetic mutant rescues the restart defect from EXO5 depletion that decreases fork progression, DNA damage repair, and cell survival. EXO5 depletion furthermore rescues survival of FANCA-deficient cells and indicates EXO5 functions epistatically with SMARCAL1 and BLM. Thus, an EXO5 axis connects ATR and BLM in directing replication fork restart. |
| Databáze: | OpenAIRE |
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