Oct-1 and CCAAT/enhancer-binding protein (C/EBP) bind to overlapping elements within the interleukin-8 promoter. The role of Oct-1 as a transcriptional repressor

J Biol Chem. 1997 Jan 24;272(4):2396-403.


Interleukin-8 (IL-8), a potent neutrophil chemoattractant, can be expressed at high levels by many different cell types after immune stimulation. In contrast, expression of IL-8 in these same cells is virtually absent in the unstimulated state, demonstrating the tight regulation of the IL-8 gene. Although much is known about how this gene is transcriptionally activated after immune stimulation, little is known about the regulation of the IL-8 promoter in the absence of immune activation. In this study we examine how the IL-8 promoter is transcriptionally regulated in the uninduced state and how these mechanisms are altered in response to immune stimulation by IL-1beta. Electrophoretic mobility shift assay and transfection studies show that the IL-8 promoter is transcriptionally regulated by both positive and negative elements. Although the nuclear factor-kappaB (NFkappaB) element regulates only inducible activity of the IL-8 promoter in response to stimulation with IL-1beta, the AP-1 and CCAAT/Enhancer-binding Protein (C/EBP) elements influence both basal and inducible activities. In contrast to these three positive regulatory elements, the binding of the ubiquitously expressed POU-homeodomain transcription factor, Oct-1, strongly represses transcriptional activity of the IL-8 promoter by binding independently to an element overlapping that of C/EBP.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • CCAAT-Enhancer-Binding Proteins
  • Caco-2 Cells
  • DNA-Binding Proteins / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Host Cell Factor C1
  • Humans
  • Interleukin-8 / genetics*
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • NF-kappa B / metabolism
  • Nuclear Proteins / metabolism*
  • Octamer Transcription Factor-1
  • Promoter Regions, Genetic*
  • Transcription Factors / metabolism*


  • CCAAT-Enhancer-Binding Proteins
  • DNA-Binding Proteins
  • HCFC1 protein, human
  • Host Cell Factor C1
  • Interleukin-8
  • NF-kappa B
  • Nuclear Proteins
  • Octamer Transcription Factor-1
  • POU2F1 protein, human
  • Transcription Factors