Previous Article | Next Article ![]()
Mol. Cell. Biol., Jan 1995, 112-119, Vol 15, No. 1
SA Godambe, DD Chaplin, T Takova, LM Read and CJ Bellone
Regulatory elements important for transcription of the murine interleukin-1
beta (IL-1 beta) gene lie within a DNase I-hypersensitive region located
> 2,000 bp upstream from the transcription start site. We have
identified within this region a novel positive regulatory element that is
required for activation of an IL-1 beta promoter- chloramphenicol
acetyltransferase (CAT) fusion gene in the murine macrophage line RAW264.7.
Electrophoretic mobility shift analysis of the 3' portion (-2315 to -2106)
of the hypersensitive region revealed at least two nuclear factor binding
sites, one of which is located between positions -2285 and -2256.
Competitive inhibition studies localized the binding site to a 15-bp
sequence between -2285 and -2271. Nuclear factor binding was lost by
mutation of the 6-bp sequence from - 2280 to -2275. The specific retarded
complex formed with RAW264.7 nuclear extract was not detected under similar
conditions with nuclear extracts from RLM-11, a murine T-cell line which
does not express IL-1 beta RNA. Mutation of the 6-bp sequence (-2280 to
-2275) in the chimeric IL-1 beta promoter -4093 +I CAT plasmid virtually
eliminated the activation of this reporter gene by lipopolysaccharide (LPS)
in transfected RAW264.7 cells. Multimerization of the 15-bp sequence
containing the core wild-type 6-bp sequence 5' of minimal homologous or
heterologous promoters in CAT reporter plasmids resulted in significant
enhancement of CAT expression compared with parallel constructs containing
the mutant 6-bp core sequence. This element was LPS independent and
position and orientation dependent. The multimerized 15- bp sequence did
not enhance expression in RLM-11 cells.(ABSTRACT TRUNCATED AT 250 WORDS)
Copyright © 1995, American Society for Microbiology
A novel cis-acting element required for lipopolysaccharide-induced transcription of the murine interleukin-1 beta gene
Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|