| Autor: |
Aune, Thomas M., Penix, Laurie A., Rincón, Mercedes R., Flavell, Richard A. |
| Zdroj: |
Molecular and Cellular Biology; January 1997, Vol. 17 Issue: 1 p199-208, 10p |
| Abstrakt: |
Acquisition of the ability to produce gamma interferon (IFN-ϒ) is a fundamental property of memory T cells and enables one subset (T helper 1 [TH1]) to deliver its effector functions. To examine regulation of IFN-ϒgene expression in a model system which recapitulates TH1 differentiation, we prepared reporter transgenic mice which express the luciferase gene under the control of proximal and distal regulatory elements (prox.IFNϒand dist.IFNϒ) from the IFN-ϒpromoter. Memory T cells, but not naive T cells, secreted IFN-ϒand expressed both prox.IFNϒand dist.IFNϒtranscriptional activities. Naive T cells required priming to become producers of IFN-ϒand to direct transcription by these elements. While both CD4+and CD8+T cells produced IFN-ϒ, only CD4+T cells expressed prox.IFNϒtranscriptional activity. Induction of transcriptional activity was inhibited by known antagonists of effector T-cell populations. Cyclosporin A inhibited transcriptional activity directed by both elements in effector T cells. Elevated cyclic AMP inhibited transcriptional activity directed by prox.IFNϒin primed CD4+T cells but enhanced transcriptional activity directed by dist.IFNϒin primed CD8+T cells. Taken together, these data show that prox.IFN ϒ and dist.IFN ϒ transcriptional activities mirror IFN-ϒgene expression in naive and memory CD4+ T cells but suggest that differences exist in regulation of IFN-ϒgene expression in CD4+and CD8+T-cell subsets. |
| Databáze: |
Supplemental Index |
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