Sp1-associated activation of macrophage inflammatory protein-2 promoter by CpG-oligodeoxynucleotide and lipopolysaccharide

Cell Mol Life Sci. 2005 Jan;62(2):188-98. doi: 10.1007/s00018-004-4399-y.

Abstract

Macrophage inflammatory protein-2 (MIP-2) is a C-X-C chemokine that is important in recruiting neutrophils to inflammatory sites. Our previous reports demonstrated that lipopolysaccharide (LPS) or CpG-oligode-oxynucleotide (CpG-ODN) rapidly induce MIP-2 gene expression in the macrophage cell line, RAW 264.7. Here, we show that the DNA sequence of the MIP-2 promoter between -114 and +14 is sufficient for strong promoter activity in LPS- or CpG-ODN-stimulated RAW 264.7 cells. Importantly, comprehensive mutant analysis reveals that an Sp1 element in the promoter region between -114 and -94 is essential for synergistic MIP-2 promoter activation by NF-kappaB and c-Jun regardless of the presence of an AP-1 site. By combining deletion or site-specific mutant analysis with immunocomplex assays, we also confirmed that Sp1 mediates the recruitment of transcription factors NF- kappaB and c-Jun in LPS- or CpG-ODN-treated RAW 264.7 cells. Several lines of experimental evidence imply that the Sp1-binding element is an important determinant of MIP-2 promoter activity, and that NF-kappaB, c-Jun and Sp1 can functionally cooperate to elicit maximal activation of the promoter.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Chemokine CXCL2
  • Chemokines / genetics*
  • Chemokines / metabolism
  • Lipopolysaccharides / pharmacology*
  • Mice
  • Molecular Sequence Data
  • NF-kappa B / metabolism
  • Oligodeoxyribonucleotides / pharmacology*
  • Promoter Regions, Genetic*
  • Proto-Oncogene Proteins c-jun / metabolism
  • Sequence Deletion
  • Sp1 Transcription Factor / metabolism*
  • Transcriptional Activation*

Substances

  • CPG-oligonucleotide
  • Chemokine CXCL2
  • Chemokines
  • Cxcl2 protein, mouse
  • Lipopolysaccharides
  • NF-kappa B
  • Oligodeoxyribonucleotides
  • Proto-Oncogene Proteins c-jun
  • Sp1 Transcription Factor