The -180 site of the IL-2 promoter is the target of CREB/CREM binding in T cell anergy.
Anergic T cells display a marked decrease in their ability to produce IL-2 even in the presence of optimal TCR and costimulatory signals. Using IL-2 enhancer/promoter-driven reporter constructs, we have previously identified a region that appears to be a target for cis transcriptional repression in anergy. This region of the promoter, which shares partial homology with a consensus AP-1-binding sequence, is located about -180 bp from the transcriptional start site. In the present study, we demonstrate that cAMP response element-binding protein/cAMP response element modulator (CREB/CREM), activating transcription factor-2/c-Jun, and Jun-Jun/Oct complexes bind to this site. However, the induction of anergy by prolonged stimulation through the TCR led to an increase in binding of only the CREB/CREM complex. Furthermore, the level of binding of this complex appeared to be up-regulated in both resting and restimulated anergic T cells. Finally, an IL-2 promoter-driven reporter construct that contained a mutation that specifically reduced the binding of the CREB/CREM complex displayed a decreased ability to be affected by anergy, while a construct that contained a mutation that decreased the binding of the Jun-Jun/Oct complex was still susceptible to anergy. These findings suggest that the -180 region of the IL-2 promoter is the target of a CREB/CREM transcriptional inhibitor that contributes to the repression of IL-2 production in T cell anergy.
Powell
J D
JD
Laboratory of Cellular and Molecular Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA. jpowell@niaid.nih.gov
Lerner
C G
CG
Ewoldt
G R
GR
Schwartz
R H
RH
D020121:5' Untranslated Regions / Q000276:immunology / Q000378:metabolism; D000818:Animals; D001667:Binding, Competitive / Q000235:genetics / Q000276:immunology; D017635:Clonal Anergy / Q000235:genetics* / Q000276:immunology; D002999:Clone Cells; D051786:Cyclic AMP Response Element Modulator; D017362:Cyclic AMP Response Element-Binding Protein / Q000302:isolation & purification / Q000378:metabolism* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism* / Q000502:physiology; D007376:Interleukin-2 / Q000235:genetics*; D016399:Lymphoma, T-Cell; D046911:Macromolecular Substances; D051379:Mice; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000276:immunology*; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D012097:Repressor Proteins; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D014407:Tumor Cells, Cultured
D020121:5' Untranslated Regions; D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D007376:Interleukin-2; D046911:Macromolecular Substances; D009687:Nuclear Proteins; D016755:Proto-Oncogene Proteins c-jun; D012097:Repressor Proteins; D051786:Cyclic AMP Response Element Modulator