Formation of a nuclear complex containing the p53 tumor suppressor, YB-1, and the Werner syndrome gene product in cells treated with UV light.
YB-1 is a multifunctional protein involved in the regulation of transcription, translation, and mRNA splicing. In recent years, several laboratories have demonstrated that YB-1 is also directly involved in the cellular response to genotoxic stress. Accordingly, one report has indicated that the Werner syndrome gene product (WRN) is eluted from an YB-1 affinity chromatography column. Werner syndrome is a rare disorder characterized by the premature onset of a number of age-related diseases, including cancer. The gene responsible for Werner syndrome encodes a DNA helicase/exonuclease protein believed to be involved in some aspect of DNA repair with p53. In this study, we demonstrate that the tumor suppressor, p53, bridges the WRN and YB-1 proteins in vitro. Microscopic analyses of fluorescent-tagged proteins and co-immunoprecipitation experiments confirmed the formation of an YB-1/p53/WRN complex in human cells, but only after treatment with UV light. We also confirmed that p53 is a major player in the translocation of GFP-YB-1 fusion proteins from the cytoplasm to several nuclear foci containing WRN proteins upon UV irradiation. Such translocation did not occur in cells treated with the topoisomerase inhibitor, etoposide, or the radiomimetic drug, bleomycin. Such results suggest that an YB-1/p53/WRN complex is formed in response to the emergence of specific DNA lesions in cells.
Centre de Recherche en Cancérologie de l'Université Laval, Hôpital Hôtel-Dieu de Québec, Centre Hospitalier Universitaire de Québec, 9 McMahon St, Que., Canada G1R 2J6.
David
D
Guay
Isabelle
I
Gaudreault
Laurent
L
Massip
Michel
M
Lebel
D021581:Active Transport, Cell Nucleus / Q000528:radiation effects; D002460:Cell Line; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism / Q000528:radiation effects; D002846:Chromatography, Affinity; D004249:DNA Damage; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005090:Exodeoxyribonucleases; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D009687:Nuclear Proteins; D010957:Plasmids / Q000235:genetics; D053484:RecQ Helicases; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D014466:Ultraviolet Rays; D000071657:Werner Syndrome Helicase; D051840:Y-Box-Binding Protein 1
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D016159:Tumor Suppressor Protein p53; D051840:Y-Box-Binding Protein 1; C070856:YBX1 protein, human; D005090:Exodeoxyribonucleases; D004265:DNA Helicases; D053484:RecQ Helicases; C098785:WRN protein, human; D000071657:Werner Syndrome Helicase