BRCA2 function in DNA binding and recombination from a BRCA2-DSS1-ssDNA structure.
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.
Yang
Haijuan
H
Department of Pharmacology, Sloan-Kettering Division, Joan and Sanford I. Weill Graduate School of Medical Sciences, Cornell University, New York, NY 10021, USA.
Jeffrey
Philip D
PD
Miller
Julie
J
Kinnucan
Elspeth
E
Sun
Yutong
Y
Thoma
Nicolas H
NH
Zheng
Ning
N
Chen
Phang-Lang
PL
Lee
Wen-Hwa
WH
Pavletich
Nikola P
NP
D000595:Amino Acid Sequence; D000818:Animals; D024682:BRCA2 Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D018797:Cell Cycle Proteins; D018360:Crystallography, X-Ray; D004247:DNA / Q000378:metabolism; D004260:DNA Repair; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D024522:Genes, BRCA2; D019077:Helix-Turn-Helix Motifs; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D046988:Proteasome Endopeptidase Complex; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D051135:Rad51 Recombinase; D051381:Rats; D011995:Recombination, Genetic
D024682:BRCA2 Protein; D018797:Cell Cycle Proteins; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D011506:Proteins; C484606:SEM1 protein, human; C108199:Shfdg1 protein, mouse; D004247:DNA; C495153:RAD51 protein, human; D051135:Rad51 Recombinase; C495154:Rad51 protein, mouse; C495155:Rad51 protein, rat; D046988:Proteasome Endopeptidase Complex