Liver-specific and proliferation-induced deoxyribonuclease I hypersensitive sites in the mouse insulin-like growth factor binding protein-1 gene

Hepatology. 1999 Nov;30(5):1187-97. doi: 10.1002/hep.510300520.

Abstract

The insulin-like growth factor binding protein-1 (IGFBP-1) gene is highly expressed in fetal, perinatal, and regenerating liver. Up-regulation is transcriptionally mediated in regenerating liver and occurs in the first few minutes to hours after partial hepatectomy. In transgenic mice a 970-bp region from -776 to +151 of the IGFBP-1 promoter was sufficient for tissue-specific and induced expression of the gene in fetal and hepatectomized livers. However weak and/or poorly regulated expression in some transgenic lines suggested the existence of other regulatory regions. Here, genomic clones containing large regions 5' of the mouse IGFBP-1 gene sequence were isolated, subcloned, and sequenced. Deoxyribonuclease I (DNaseI) hypersensitivity analyses identified clusters of tissue-specific nuclease-sensitive sites in the promoter region, -100 to -300, -2,300, -3,100, and -5,000 along with other weak sites. After partial hepatectomy, enhanced sensitivity and/or novel sites were detected in the -100/-300, -5,000, and -3,100 regions, the promoter region remaining the most hypersensitive. A subset of these sites was present in fetal and perinatal livers. Novel tissue-specific sites that interacted with C/EBP and hepatic nuclear factor 3 (HNF3) transcription factors were identified in the -3,100 region. A hepatectomy-induced DNA binding complex containing the transcription factor USF1 was identified within the -100 to -300 region of the promoter. These results suggested that a complex array of tissue-specific and hepatic proliferation-induced transcription factors combine to regulate both the proximal promoter and more distal regulatory elements of the IGFBP-1 gene.

Publication types

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

MeSH terms

  • Animals
  • Base Sequence
  • Carcinoma, Hepatocellular
  • Cloning, Molecular
  • Deoxyribonuclease I
  • Fetus
  • Gene Expression Regulation, Developmental*
  • Hepatectomy
  • Humans
  • Insulin-Like Growth Factor Binding Protein 1 / genetics*
  • Kidney / metabolism
  • Liver / cytology*
  • Liver / metabolism*
  • Liver Neoplasms
  • Liver Regeneration*
  • Mice
  • Mice, Transgenic
  • Molecular Sequence Data
  • Promoter Regions, Genetic*
  • Recombinant Proteins / biosynthesis
  • Regulatory Sequences, Nucleic Acid
  • Restriction Mapping
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid
  • Spleen / metabolism
  • Substrate Specificity
  • Transfection
  • Tumor Cells, Cultured

Substances

  • Insulin-Like Growth Factor Binding Protein 1
  • Recombinant Proteins
  • Deoxyribonuclease I