title: Modulation of the Pyrococcus abyssi NucS endonuclease activity by replication clamp at functional and structural levels.
abstract: Pyrococcus abyssi NucS is the founding member of a new family of structure-specific DNA endonucleases that interact with the replication clamp proliferating cell nuclear antigen (PCNA). Using a combination of small angle x-ray scattering and surface plasmon resonance analyses, we demonstrate the formation of a stable complex in solution, in which one molecule of the PabNucS homodimer binds to the outside surface of the PabPCNA homotrimer. Using fluorescent labels, PCNA is shown to increase the binding affinity of NucS toward single-strand/double-strand junctions on 5' and 3' flaps, as well as to modulate the cleavage specificity on the branched DNA structures. Our results indicate that the presence of a single major contact between the PabNucS and PabPCNA proteins, together with the complex-induced DNA bending, facilitate conformational flexibility required for specific cleavage at the single-strand/double-strand DNA junction.
authors.affiliation: Ifremer, UMR6197, Laboratoire de Microbiologie des Environnements Extrêmes, 29280 Plouzané, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Creze
authors.forename: Alessio
authors.initials: A
authors.lastname: Ligabue
authors.forename: Sébastien
authors.initials: S
authors.lastname: Laurent
authors.forename: Roxane
authors.initials: R
authors.lastname: Lestini
authors.forename: Sergey P
authors.initials: SP
authors.lastname: Laptenok
authors.forename: Joelle
authors.initials: J
authors.lastname: Khun
authors.forename: Marten H
authors.initials: MH
authors.lastname: Vos
authors.forename: Mirjam
authors.initials: M
authors.lastname: Czjzek
authors.forename: Hannu
authors.initials: H
authors.lastname: Myllykallio
authors.forename: Didier
authors.initials: D
authors.lastname: Flament
mesh_terms: D000465:Algorithms; D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001667:Binding, Competitive; D004261:DNA Replication / Q000235:genetics; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000378:metabolism; D004720:Endonucleases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D018809:Proliferating Cell Nuclear Antigen / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D043903:Pyrococcus abyssi / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D053838:Scattering, Small Angle; D020349:Surface Plasmon Resonance; D014961:X-Ray Diffraction
chemical_list: D019843:Archaeal Proteins; D019641:DNA, Archaeal; D004277:DNA, Single-Stranded; D018809:Proliferating Cell Nuclear Antigen; D004720:Endonucleases