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BRCA2 function in DNA binding and recombination from a BRCA2-DSS1-ssDNA structure.

Haijuan Yang·Philip D Jeffrey·Julie Miller·Elspeth Kinnucan·Yutong Sun·Nicolas H Thoma·Ning Zheng·Phang-Lang Chen·Wen-Hwa Lee·Nikola P Pavletich
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Abstract

Mutations in the BRCA2 (breast cancer susceptibility gene 2) tumor suppressor lead to chromosomal instability due to defects in the repair of double-strand DNA breaks (DSBs) by homologous recombination, but BRCA2's role in this process has been unclear. Here, we present the 3.1 angstrom crystal structure of a approximately 90-kilodalton BRCA2 domain bound to DSS1, which reveals three oligonucleotide-binding (OB) folds and a helix-turn-helix (HTH) motif. We also (i) demonstrate that this BRCA2 domain binds single-stranded DNA, (ii) present its 3.5 angstrom structure bound to oligo(dT)9, (iii) provide data that implicate the HTH motif in dsDNA binding, and (iv) show that BRCA2 stimulates RAD51-mediated recombination in vitro. These findings establish that BRCA2 functions directly in homologous recombination and provide a structural and biochemical basis for understanding the loss of recombination-mediated DSB repair in BRCA2-associated cancers.

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Amino Acid SequenceAnimalsBRCA2 ProteinBinding SitesCell Cycle ProteinsCrystallography, X-RayDNADNA RepairDNA, Single-StrandedDNA-Binding ProteinsGenes, BRCA2Helix-Turn-Helix MotifsHumansHydrogen BondingHydrophobic and Hydrophilic InteractionsMiceMolecular Sequence DataMutationProteasome Endopeptidase ComplexProtein ConformationProtein FoldingProtein Structure, SecondaryProtein Structure, TertiaryProteinsRad51 RecombinaseRatsRecombination, GeneticJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Haijuan Yang, Philip D Jeffrey, Julie Miller, Elspeth Kinnucan, Yutong Sun, Nicolas H Thoma, Ning Zheng, Phang-Lang Chen, Wen-Hwa Lee, Nikola P Pavletich. 2002-09-13. BRCA2 function in DNA binding and recombination from a BRCA2-DSS1-ssDNA structure.. https://doi.org/10.1126/science.297.5588.1837

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