1. Characterization of a novel PMA-inducible pathway of interleukin-13 gene expression in T cells
- Author
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Giovanni Florio, Marsha Wills-Karp, Jessica Roman, Rongbing Chen, Antonella Cianferoni, Vincenzo Casolaro, Judith C. Keen, Steve N. Georas, and Jia Guo
- Subjects
Transcription, Genetic ,T-Lymphocytes ,Immunology ,Molecular Sequence Data ,Biology ,Cell Line ,Mice ,Species Specificity ,Interleukin 26 ,Gene expression ,Immunology and Allergy ,Cytotoxic T cell ,Animals ,Humans ,IL-2 receptor ,Promoter Regions, Genetic ,Cells, Cultured ,Protein Kinase C ,Interleukin 3 ,Interleukin-13 ,Base Sequence ,Reverse Transcriptase Polymerase Chain Reaction ,Promoter ,Original Articles ,Molecular biology ,Gene Expression Regulation ,Interleukin 13 ,Interleukin 12 ,Tetradecanoylphorbol Acetate ,Signal Transduction - Abstract
Although interleukin 13 (IL-13) is an important mediator of asthma and allergic diseases, the molecular mechanisms regulating IL-13 gene expression are not well understood. This study was designed to define the molecular mechanisms governing IL-13 gene expression in T cells. IL-13 expression was examined in human peripheral blood T cells and in the EL-4 T-cell line by enzyme-linked immunosorbent assay and reverse-transcription polymerase chain reaction. An IL-13 promoter deletion analysis was performed using luciferase-based reporter plasmids transiently transfected into EL-4 cells by electroporation. DNA binding factors were investigated using electrophoretic mobility shift assays. In contrast to IL-4 expression, which required concomitant activation of calcium- and protein kinase C- (PKC-) dependent signalling pathways, PKC activation alone was sufficient for IL-13 protein secretion in mitogen-primed (but not resting) peripheral blood T cells, and for IL-13 mRNA expression and promoter activity in EL-4 T cells. Promoter deletion analysis localized a phorbol 12-myristate 13-acetate (PMA) -sensitive element to a proximal promoter region between −109 and −79 base pairs upstream from the IL-13 transcription start site. This promoter region supported the binding of both constitutive and PMA-inducible nuclear factors in gel shift assays.
- Published
- 2006