Structure and function of a novel endonuclease acting on branched DNA substrates.
Branched DNA structures that occur during DNA repair and recombination must be efficiently processed by structure-specific endonucleases in order to avoid cell death. In the present paper, we summarize our screen for new interaction partners for the archaeal replication clamp that led to the functional characterization of a novel endonuclease family, dubbed NucS. Structural analyses of Pyrococcus abyssi NucS revealed an unexpected binding site for ssDNA (single-stranded DNA) that directs, together with the replication clamp, the nuclease activity of this protein towards ssDNA-dsDNA (double-stranded DNA) junctions. Our studies suggest that understanding the detailed architecture and dynamic behaviour of the NucS (nuclease specific for ssDNA)-PCNA (proliferating-cell nuclear antigen) complex with DNA will be crucial for identification of its physiologically relevant activities.
IFREMER, UMR 6197, Laboratoire de Microbiologie des Environnements Extrêmes, Technopole Brest-Iroise, BP70 29280 Plouzané, France.
Christophe
C
Creze
Roxane
R
Lestini
Joelle
J
Kühn
Alessio
A
Ligabue
Hubert F
HF
Becker
Mirjam
M
Czjzek
Didier
D
Flament
Hannu
H
Myllykallio
D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000378:metabolism*; D004706:Endodeoxyribonucleases / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011487:Protein Conformation; D043903:Pyrococcus abyssi / Q000235:genetics / Q000378:metabolism; D012260:Ribonucleases / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment
D019843:Archaeal Proteins; D001426:Bacterial Proteins; D004277:DNA, Single-Stranded; D018809:Proliferating Cell Nuclear Antigen; D004706:Endodeoxyribonucleases; D012260:Ribonucleases; C117079:ribonuclease HIII