FRA2 is a STAT5 target gene regulated by IL-2 in human CD4 T cells

PLoS One. 2014 Feb 28;9(2):e90370. doi: 10.1371/journal.pone.0090370. eCollection 2014.

Abstract

Signal transducers and activators of transcription 5(STAT5) are cytokine induced signaling proteins, which regulate key immunological processes, such as tolerance induction, maintenance of homeostasis, and CD4 T-effector cell differentiation. In this study, transcriptional targets of STAT5 in CD4 T cells were studied by Chromatin Immunoprecipitation (ChIP). Genomic mapping of the sites cloned and identified in this study revealed the striking observation that the majority of STAT5-binding sites mapped to intergenic (>50 kb upstream) or intronic, rather than promoter proximal regions. Of the 105 STAT5 responsive binding sites identified, 94% contained the canonical (IFN-γ activation site) GAS motifs. A number of putative target genes identified here are associated with tumor biology. Here, we identified Fos-related antigen 2 (FRA2) as a transcriptional target of IL-2 regulated STAT5. FRA2 is a basic -leucine zipper (bZIP) motif 'Fos' family transcription factor that is part of the AP-1 transcription factor complex and is also known to play a critical role in the progression of human tumours and more recently as a determinant of T cell plasticity. The binding site mapped to an internal intron within the FRA2 gene. The epigenetic architecture of FRA2, characterizes a transcriptionally active promoter as indicated by enrichment for histone methylation marks H3K4me1, H3K4me2, H3K4me3, and transcription/elongation associated marks H2BK5me1 and H4K20me1. FRA2 is regulated by IL-2 in activated CD4 T cells. Consistently, STAT5 bound to GAS sequence in the internal intron of FRA2 and reporter gene assays confirmed IL-2 induced STAT5 binding and transcriptional activation. Furthermore, addition of JAK3 inhibitor (R333) or Daclizumab inhibited the induction in TCR stimulated cells. Taken together, our data suggest that FRA2 is a novel STAT5 target gene, regulated by IL-2 in activated CD4 T cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Monoclonal, Humanized / pharmacology
  • Base Sequence
  • Binding Sites
  • CD4-Positive T-Lymphocytes / cytology
  • CD4-Positive T-Lymphocytes / drug effects
  • CD4-Positive T-Lymphocytes / metabolism*
  • DNA, Intergenic / chemistry
  • DNA, Intergenic / metabolism
  • Daclizumab
  • Epigenesis, Genetic
  • Fos-Related Antigen-2 / genetics*
  • Fos-Related Antigen-2 / metabolism
  • Gene Expression Regulation
  • Genes, Reporter
  • HEK293 Cells
  • Histones / genetics
  • Histones / metabolism
  • Humans
  • Immunoglobulin G / pharmacology
  • Interleukin-2 / pharmacology*
  • Introns
  • Janus Kinase 3 / antagonists & inhibitors
  • Janus Kinase 3 / genetics
  • Janus Kinase 3 / metabolism
  • Luciferases / genetics
  • Luciferases / metabolism
  • Lymphocyte Activation
  • Methylation
  • Molecular Sequence Data
  • Primary Cell Culture
  • Protein Binding
  • STAT5 Transcription Factor / genetics*
  • STAT5 Transcription Factor / metabolism
  • Signal Transduction
  • Transcription, Genetic

Substances

  • Antibodies, Monoclonal, Humanized
  • DNA, Intergenic
  • FOSL2 protein, human
  • Fos-Related Antigen-2
  • Histones
  • Immunoglobulin G
  • Interleukin-2
  • STAT5 Transcription Factor
  • Daclizumab
  • Luciferases
  • JAK3 protein, human
  • Janus Kinase 3