Dynamic binding of Ku80, Ku70 and NF90 to the IL-2 promoter in vivo in activated T-cells.
IL-2 gene expression in activated T-cells is initiated by chromatin remodeling at the IL-2 proximal promoter and conversion of a transcriptional repressor into a potent transcriptional activator. A purine-box regulator complex was purified from activated Jurkat T-cell nuclei based on sequence-specific DNA binding to the antigen receptor response element (ARRE)/nuclear factor of activated T-cells (NF-AT) target DNA sequence in the proximal IL-2 promoter. ARRE DNA-binding subunits were identified as NF90, NF45 and systemic lupus erythematosis autoantigens, Ku80 and Ku70. Monoclonal antibodies to Ku80, Ku70 and NF90 specifically inhibit constitutive and inducible ARRE DNA-binding activity in Jurkat T-cells. Ku80, Ku70 and NF90 bind specifically to the IL-2 gene promoter in vivo, as demonstrated by chromatin immunoprecipitation. Activation of Jurkat T-cells and mouse primary spleen cells induces binding of Ku80 and NF90 to the IL-2 promoter in vivo, and decreases binding of Ku70 to the IL-2 promoter in vivo, and these dynamic changes are inhibited by immunosuppressants cyclosporin A and triptolide. Dynamic changes in binding of Ku80, Ku70 and NF90 to the IL-2 proximal promoter in vivo correlate with chromatin remodeling and transcriptional initiation in activated T-cells.
Shi
Lingfang
L
Pulmonary and Critical Care Medicine, Stanford University Medical Center, Stanford, CA 94305-5236, USA.
Qiu
Daoming
D
Zhao
Guohua
G
Corthesy
Blaise
B
Lees-Miller
Susan
S
Reeves
Westley H
WH
Kao
Peter N
PN
D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism*; D001665:Binding Sites; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D016572:Cyclosporine / Q000494:pharmacology; D051747:DNA-Activated Protein Kinase / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004224:Diterpenes / Q000494:pharmacology; D004852:Epoxy Compounds / Q000494:pharmacology; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007376:Interleukin-2 / Q000235:genetics*; D019169:Jurkat Cells; D000072200:Ku Autoantigen; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D051903:Nuclear Factor 45 Protein / Q000378:metabolism; D050779:Nuclear Factor 90 Proteins / Q000378:metabolism*; D010616:Phenanthrenes / Q000494:pharmacology; D011401:Promoter Regions, Genetic; D021122:Protein Subunits / Q000378:metabolism; D020218:Response Elements; D013601:T-Lymphocytes / Q000276:immunology*
D034961:Antigens, Nuclear; D004268:DNA-Binding Proteins; D004224:Diterpenes; D004852:Epoxy Compounds; D007166:Immunosuppressive Agents; D007376:Interleukin-2; D051903:Nuclear Factor 45 Protein; D050779:Nuclear Factor 90 Proteins; D010616:Phenanthrenes; D021122:Protein Subunits; C001899:triptolide; D016572:Cyclosporine; D051747:DNA-Activated Protein Kinase; C000606509:Xrcc6 protein, human; C000606510:Xrcc6 protein, mouse; D000072200:Ku Autoantigen