Functional characterization of IL-13 receptor alpha2 gene promoter: a critical role of the transcription factor STAT6 for regulated expression

Oncogene. 2003 May 29;22(22):3386-94. doi: 10.1038/sj.onc.1206352.


Interleukin (IL)-4 and IL-13 are two structurally and functionally related cytokines that have overlapping but also distinct biological activities. One of the components of the IL-13 receptor, the alpha2 chain (IL-13Ralpha2), has been reported to downregulate the cell responsiveness to IL-13, without affecting IL-4 signaling. Here, we report that TNFalpha synergizes with either IL-4 or IL-13 in inducing the IL-13Ralpha2 chain at both the mRNA and protein levels in the HaCaT human keratinocyte cell line. Further studies by 5'RACE identified as yet undescribed exonic sequences of the IL-13Ralpha2 5'UTR, provided evidence for the expression of alternatively spliced IL-13Ralpha2 transcripts and defined the transcription start of the IL-13Ralpha2 gene. A 1.5 kb region upstream of the first exon of the IL-13Ralpha2 gene displayed basal promoter activity when inserted in a reporter plasmid and transiently transfected in HaCaT cells. This promoter activity was further increased in response to IL-4 and IL-13. Furthermore, by electrophoretic mobility shift assay and site-directed mutagenesis, we showed that the IL-4/IL-13-induced promoter activity depended upon a positively acting STAT6 response element. Finally, TNFalpha was shown to potentiate IL-4/IL-13-induced IL-13Ralpha2 promoter activity when the same reporter construct was studied in stably but not in transiently transfected cells. These results suggest that the synergistic effect of TNFalpha on IL-4/IL-13-induced IL-13Ralpha2 expression is dependent upon chromatin re-modeling events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5' Flanking Region
  • Base Sequence
  • Cell Line
  • Gene Expression Regulation*
  • Humans
  • In Vitro Techniques
  • Interleukin-13 / metabolism
  • Interleukin-13 Receptor alpha1 Subunit
  • Interleukin-4 / metabolism
  • Keratinocytes
  • Molecular Sequence Data
  • Promoter Regions, Genetic*
  • Receptors, Interleukin / genetics*
  • Receptors, Interleukin / metabolism
  • Receptors, Interleukin-13
  • STAT6 Transcription Factor
  • Sequence Analysis, DNA
  • Trans-Activators / genetics*
  • Trans-Activators / metabolism


  • IL13RA1 protein, human
  • Interleukin-13
  • Interleukin-13 Receptor alpha1 Subunit
  • Receptors, Interleukin
  • Receptors, Interleukin-13
  • STAT6 Transcription Factor
  • STAT6 protein, human
  • Trans-Activators
  • Interleukin-4