Transiently and Stably Introduced CCAAT/enhancer-binding-protein Genes Are Constitutively Expressed in Cultured Cells

Eur J Biochem. 1992 Sep 1;208(2):501-9. doi: 10.1111/j.1432-1033.1992.tb17214.x.

Abstract

CCAAT/enhancer-binding protein (C/EBP) is expressed in certain cell types including hepatocytes and adipocytes. In order to understand the mechanisms that control the expression of the mouse C/EBP gene in the liver as well as in adipocytes, we have studied both the endogenous gene and transfected C/EBP gene constructs. The initiation site of transcription was identified and a strong liver-specific DNase-I hypersensitive site located at -3 kb, which does not appear to contribute functionally to the regulation of the gene in a variety of either transiently or stably transfected cells with constructs which include sequences up to 6-kb upstream of the transcription start. C/EBP gene expression during the transition from preadipocytes to adipocytes was shown to be controlled at the level of transcription. However, adipocytes stably transfected with constructs that include -3.3 kb upstream of the C/EBP gene do not express the reporter genes in a differentiation-specific manner. We detected several DNA-binding proteins that interact with the upstream sites of the C/EBP gene. Those include two labile and two heat-stable site-specific DNA-binding proteins that are present in nuclear extracts from several tissues and cultured cell lines.

Publication types

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

MeSH terms

  • Adipose Tissue / cytology
  • Adipose Tissue / metabolism
  • Animals
  • Base Sequence
  • Binding Sites
  • CCAAT-Enhancer-Binding Proteins
  • Carcinoma, Hepatocellular
  • Cell Differentiation
  • DNA-Binding Proteins / analysis
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Deoxyribonuclease I / metabolism
  • Gene Expression*
  • HeLa Cells
  • Humans
  • Liver Neoplasms
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred DBA
  • Molecular Sequence Data
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism
  • Promoter Regions, Genetic
  • Transcription, Genetic
  • Transfection
  • Tumor Cells, Cultured

Substances

  • CCAAT-Enhancer-Binding Proteins
  • DNA-Binding Proteins
  • Nuclear Proteins
  • Deoxyribonuclease I

Associated data

  • GENBANK/M85175
  • GENBANK/M85176
  • GENBANK/M85177
  • GENBANK/S42403
  • GENBANK/S42404
  • GENBANK/S44547
  • GENBANK/X65179
  • GENBANK/X65180
  • GENBANK/X65181
  • GENBANK/Z11975