title: Mechanism of Archaeal MCM Helicase Recruitment to DNA Replication Origins.
abstract: Cellular DNA replication origins direct the recruitment of replicative helicases via the action of initiator proteins belonging to the AAA+ superfamily of ATPases. Archaea have a simplified subset of the eukaryotic DNA replication machinery proteins and possess initiators that appear ancestral to both eukaryotic Orc1 and Cdc6. We have reconstituted origin-dependent recruitment of the homohexameric archaeal MCM in vitro with purified recombinant proteins. Using this system, we reveal that archaeal Orc1-1 fulfills both Orc1 and Cdc6 functions by binding to a replication origin and directly recruiting MCM helicase. We identify the interaction interface between these proteins and reveal how ATP binding by Orc1-1 modulates recruitment of MCM. Additionally, we provide evidence that an open-ring form of the archaeal MCM homohexamer is loaded at origins.
authors.affiliation: Department of Molecular and Cellular Biochemistry, Indiana University, Simon Hall MSB, 212 S Hawthorne Drive, Bloomington, IN 47405, USA.
authors.forename: Rachel Y
authors.initials: RY
authors.lastname: Samson
authors.affiliation: Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA.
authors.forename: Priyanka D
authors.initials: PD
authors.lastname: Abeyrathne
authors.affiliation: Department of Molecular and Cellular Biochemistry, Indiana University, Simon Hall MSB, 212 S Hawthorne Drive, Bloomington, IN 47405, USA; Department of Biology, Indiana University, Simon Hall MSB, 212 S Hawthorne Drive, Bloomington, IN 47405, USA. Electronic address: stedbell@indiana.edu.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Bell
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism*; D004265:DNA Helicases / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D018741:Replication Origin; D016944:Sulfolobus / Q000201:enzymology*
chemical_list: D019843:Archaeal Proteins; D000255:Adenosine Triphosphate; D004265:DNA Helicases