title: A critical role of the 3' terminus of nascent DNA chains in recognition of stalled replication forks.
abstract: Arrest of replication forks by various internal and external threats evokes a myriad of cellular reactions, collectively known as DNA replication checkpoint responses. In bacteria, PriA is essential for restoration of stalled replication forks and recombinational repair of double-stranded DNA breaks and is a candidate sensor protein that may recognize arrested forks. Here, we report that PriA protein specifically recognizes 3' termini of arrested nascent DNA chains at model stalled replication forks in vitro. Mutations in the putative "3' terminus binding pocket" present in the N-terminal segment of PriA result in reduced binding to stalled replication fork structures and loss of its biological functions. The results suggest a mechanism by which stalled replication forks are recognized by a sensor protein for checkpoint responses.
authors.affiliation: Department of Structural Biology, Biomolecular Engineering Research Institute, Suita, Osaka 565-0874, Japan.
authors.forename: Toshimi
authors.initials: T
authors.lastname: Mizukoshi
authors.forename: Taku
authors.initials: T
authors.lastname: Tanaka
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Arai
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kohda
authors.forename: Hisao
authors.initials: H
authors.lastname: Masai
mesh_terms: D024509:3' Flanking Region / Q000502:physiology*; D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D001665:Binding Sites / Q000235:genetics; D004249:DNA Damage; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009690:Nucleic Acid Conformation; D016415:Sequence Alignment
chemical_list: D029968:Escherichia coli Proteins; D000251:Adenosine Triphosphatases; C506743:priA protein, E coli; D004265:DNA Helicases