Regulation of LPS-mediated induction of C/EBPδ gene expression in livers of young and aged mice

Jeffrey P. Rabek, Sheen Scott, Ching Chyuan Hsieh, Peter D. Reisner, John Papaconstantinou

Research output: Contribution to journalArticle

18 Scopus citations

Abstract

The C/EBP family of transcription factors plays a major role in the regulation of families of stress response genes, in particular, the acute phase response genes. We have examined expression of the C/EBPδ gene during the bacterial lipopolysaccharide mediated induction of the acute phase response in livers of young (4 months) and aged (24-28 months) male C57B1/6 mice by Northern, Western, and Southwestern analyses. C/EBPδ mRNA is present at a low constitutive level, is induced by lipopolysaccharide, and reaches the same induced level in young and aged mice. Aged mice, however, show a higher constitutive, uninduced mRNA pool level and a delay in recovery to uninduced levels after lipopolysaccharide treatment. C/EBPδ mRNA is observable 30 min after lipopolysaccharide in total RNA, cytoplasmic and polysomal fractions. Specific full length 28-kDa nascent peptides are detectable in polysomes 90 min after lipopolysaccharide. mRNA and nascent peptides cosediment with large polysomes and C/EBPδ mRNA is shifted to larger polysomes in lipopolysaccharide treated aged mice, consistent with an increased rate of initiation. Specific DNA-binding activity of C/EBPδ protein in nuclear extracts was examined by electromobility shift and antibody supershift assay. The levels of C/EBPδ binding-activity, are consistent with the changes in mRNA levels in young lipopolysaccharide treated livers. These studies support our hypothesis that aged mice exhibit a state of chronic inflammation or stress in the absence of a stressor.

Original languageEnglish (US)
Pages (from-to)137-147
Number of pages11
JournalBiochimica et Biophysica Acta - Gene Structure and Expression
Volume1398
Issue number2
DOIs
StatePublished - Jun 16 1998

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Keywords

  • Acute-phase response
  • Aging
  • Lipopolysaccharide
  • Transcription
  • Translation

ASJC Scopus subject areas

  • Biochemistry
  • Genetics
  • Structural Biology
  • Biophysics

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