Characterization of the promoter elements required for hepatic and intestinal transcription of the human apoB gene: definition of the DNA-binding site of a tissue-specific transcriptional factor.
The promoter elements important for intestinal and hepatic transcription of the human apoB gene have been localized downstream of nucleotide -150. Footprinting analysis using hepatic nuclear extracts identified four protected regions, -124 to -100, -97 to -93, -86 to -33, and +33 to +52. Gel electrophoretic mobility shift assays showed that multiple factors interact with the apoB sequence -86 to -33, while the region -88 to -61 binds a single nuclear factor. Methylation interference analysis and nucleotide substitution mutagenesis identified the binding site of the factor between residues -78 and -68. Binding competition experiments indicate that this factor recognizes the regulatory elements of other liver-specific genes.
Kardassis
D
D
Department of Medicine, Housman Medical Research Center, Boston University Medical Center, Massachusetts 02118.
Hadzopoulou-Cladaras
M
M
Ramji
D P
DP
Cortese
R
R
Zannis
V I
VI
Cladaras
C
C
D001055:Apolipoproteins B / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D004247:DNA / Q000235:genetics / Q000378:metabolism; D005796:Genes; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008745:Methylation; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
D001055:Apolipoproteins B; D009687:Nuclear Proteins; D014157:Transcription Factors; D004247:DNA; D015500:Chloramphenicol O-Acetyltransferase