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.
Centre for Molecular Biology and Neuroscience, and Institute of Medical Microbiology, University of Oslo, Rikshospitalet, 0027 Oslo, Norway.
Kathy
K
Baynton
Marit
M
Otterlei
Magnar
M
Bjørås
Cayetano
C
von Kobbe
Vilhelm A
VA
Bohr
Erling
E
Seeberg
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