Stat6 and c-Jun mediate Th2 cell-specific IL-24 gene expression

J Immunol. 2011 Apr 1;186(7):4098-109. doi: 10.4049/jimmunol.1002620. Epub 2011 Feb 25.

Abstract

TCR signaling regulates multiple aspects of T cell function by controlling expression of various cytokine genes. IL-24 is a multifunctional cytokine belonging to the IL-10 family. It displays anticancer effects in diverse cancer cells and regulates immunopathology of psoriasis and rheumatoid arthritis. IL-24 also plays an important role in B cell differentiation. Mouse IL-24 gene is selectively expressed in activated Th2 cells upon TCR stimulation. However, the molecular mechanisms by which TCR stimulation induces IL-24 gene expression are still unclear. In this study, to elucidate the mechanism of Th2 cell-specific expression of IL-24, we identified a proximal promoter region (-157/+95 bp) that plays critical role in activating the IL-24 gene in Th2 cells. This region has a Th2 cell-specific open chromatin structure along with permissive histone modifications. In vivo binding of Stat6 and AP-1 (c-Jun) to the IL-24 promoter locus in Th2 cells synergistically transactivated the IL-24 promoter. Stat6 and c-Jun proteins were found to physically cooperate with each other and upregulated IL-24 gene transcription. Knockdown of either Stat6 or c-Jun suppressed endogenous IL-24 gene expression in Th2 cells. In summary, TCR stimulation induces IL-24 expression in Th2 cells by the coordinate action of Stat6 and c-Jun transcription factors at the transcriptional level.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Cell Line, Tumor
  • Epitopes, T-Lymphocyte / immunology*
  • Gene Expression Regulation / immunology*
  • HEK293 Cells
  • Humans
  • Interleukins / biosynthesis*
  • Interleukins / genetics
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Promoter Regions, Genetic / immunology
  • Protein Binding / genetics
  • Protein Binding / immunology
  • Proto-Oncogene Proteins c-jun / physiology*
  • Rats
  • Receptors, Antigen, T-Cell / physiology
  • STAT6 Transcription Factor / physiology*
  • Th2 Cells / cytology
  • Th2 Cells / immunology*
  • Th2 Cells / metabolism*
  • Transcription Factor AP-1 / physiology
  • Tumor Cells, Cultured

Substances

  • Epitopes, T-Lymphocyte
  • Interleukins
  • Proto-Oncogene Proteins c-jun
  • Receptors, Antigen, T-Cell
  • STAT6 Transcription Factor
  • Stat6 protein, mouse
  • Transcription Factor AP-1
  • interleukin-24