FasL promoter activation by IL-2 through SP1 and NFAT but not Egr-2 and Egr-3.
Recently activated peripheral T cells treated with IL-2 for 4 days expressed Fas ligand (FasL)-mediated cytotoxicity. These IL-2-treated T cells had high nuclear expression of SP1 and NFAT, but lacked the Egr-2 and Egr-3 that could be induced by anti-CD3 stimulation and had been implicated in FasL gene activation. A minimal promoter region that responded to IL-2 was identified by transient transfection assays using deletion mutants. The data suggests that the GGGCGGAAA site present in the 5' end of the minimal FasL promoter is critical to IL-2-induced FasL gene activation. The GGGCGGAAA sequence contains an overlapping site used by two transcription factor families, one (GGGCGG) for the SP1 family and the other (GGAAA) for the NFAT family. FasL promoter activity was partially but statistically significantly reduced with constructs mutated at either site. More activity was lost with a construct mutated at both sites. In contrast, mutation at the Egr site had no effect on IL-2-induced FasL promoter activity. Our study identified a new FasL promoter site responding to IL-2-induced SP1 and NFAT factors. Furthermore, the nuclei of IL-2-treated cells express SP1 and NFAT, but not Egr-2 and Egr-3, for FasL gene activation.
Xiao
S
S
Department of Pathology, Boston University School of Medicine, Boston, USA.
Matsui
K
K
Fine
A
A
Zhu
B
B
Marshak-Rothstein
A
A
Widom
R L
RL
Ju
S T
ST
D000818:Animals; D001665:Binding Sites; D002457:Cell Extracts; D002467:Cell Nucleus; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051767:Early Growth Response Protein 2; D051776:Early Growth Response Protein 3; D053222:Fas Ligand Protein; D007376:Interleukin-2 / Q000378:metabolism* / Q000494:pharmacology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D016297:Mutagenesis, Site-Directed; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D011401:Promoter Regions, Genetic; D017384:Sequence Deletion; D016329:Sp1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation; D014162:Transfection
D002457:Cell Extracts; D004268:DNA-Binding Proteins; D051767:Early Growth Response Protein 2; C497327:Egr2 protein, mouse; C497369:Egr3 protein, mouse; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D051776:Early Growth Response Protein 3