title: Structure of the Rad50 DNA double-strand break repair protein in complex with DNA.
abstract: The Mre11-Rad50 nuclease-ATPase is an evolutionarily conserved multifunctional DNA double-strand break (DSB) repair factor. Mre11-Rad50's mechanism in the processing, tethering, and signaling of DSBs is unclear, in part because we lack a structural framework for its interaction with DNA in different functional states. We determined the crystal structure of Thermotoga maritima Rad50(NBD) (nucleotide-binding domain) in complex with Mre11(HLH) (helix-loop-helix domain), AMPPNP, and double-stranded DNA. DNA binds between both coiled-coil domains of the Rad50 dimer with main interactions to a strand-loop-helix motif on the NBD. Our analysis suggests that this motif on Rad50 does not directly recognize DNA ends and binds internal sites on DNA. Functional studies reveal that DNA binding to Rad50 is not critical for DNA double-strand break repair but is important for telomere maintenance. In summary, we provide a structural framework for DNA binding to Rad50 in the ATP-bound state.
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Rojowska
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Lammens
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Florian U
authors.initials: FU
authors.lastname: Seifert
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Direnberger
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Heidi
authors.initials: H
authors.lastname: Feldmann
authors.affiliation: Department of Biochemistry and Gene Center, Ludwig-Maximilians-University, Munich, Germany Center for Integrated Protein Sciences, Munich, Germany hopfner@genzentrum.lmu.de.
authors.forename: Karl-Peter
authors.initials: KP
authors.lastname: Hopfner
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D003461:Crystallography; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D045643:DNA Repair Enzymes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000737:chemistry*; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D059505:Telomere Homeostasis / Q000235:genetics; D020124:Thermotoga maritima / Q000201:enzymology*
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D004247:DNA; D045643:DNA Repair Enzymes
keywords: DNA double‐strand break repair; Mre11–Rad50; crystal structure; homologous recombination; protein:DNA complex