WRN interacts physically and functionally with the recombination mediator protein RAD52.
Werner syndrome (WS) is a premature aging disorder that predisposes affected individuals to cancer development. The affected gene, WRN, encodes an RecQ homologue whose precise biological function remains elusive. Altered DNA recombination is a hallmark of WS cells suggesting that WRN plays an important role in these pathways. Here we report a novel physical and functional interaction between WRN and the homologous recombination mediator protein RAD52. Fluorescence resonance energy transfer (FRET) analyses show that WRN and RAD52 form a complex in vivo that co-localizes in foci associated with arrested replication forks. Biochemical studies demonstrate that RAD52 both inhibits and enhances WRN helicase activity in a DNA structure-dependent manner, whereas WRN increases the efficiency of RAD52-mediated strand annealing between non-duplex DNA and homologous sequences contained within a double-stranded plasmid. These results suggest that coordinated WRN and RAD52 activities are involved in replication fork rescue after DNA damage.
Baynton
Kathy
K
Centre for Molecular Biology and Neuroscience, and Institute of Medical Microbiology, University of Oslo, Rikshospitalet, 0027 Oslo, Norway.
Otterlei
Marit
M
Bjørås
Magnar
M
von Kobbe
Cayetano
C
Bohr
Vilhelm A
VA
Seeberg
Erling
E
D015153:Blotting, Western; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004265:DNA Helicases / Q000737:chemistry* / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005090:Exodeoxyribonucleases; D031541:Fluorescence Resonance Energy Transfer; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009841:Oligonucleotides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011233:Precipitin Tests; D011485:Protein Binding; D051721:Rad52 DNA Repair and Recombination Protein; D053484:RecQ Helicases; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D011995:Recombination, Genetic; D013379:Substrate Specificity; D014162:Transfection; D020798:Two-Hybrid System Techniques; D000071657:Werner Syndrome Helicase
D004268:DNA-Binding Proteins; D009841:Oligonucleotides; C497194:RAD52 protein, human; D051721:Rad52 DNA Repair and Recombination Protein; D011993:Recombinant Fusion Proteins; D004247:DNA; D005090:Exodeoxyribonucleases; D004265:DNA Helicases; D053484:RecQ Helicases; C098785:WRN protein, human; D000071657:Werner Syndrome Helicase