Tissue-specific transcription of the mouse alpha-fetoprotein gene promoter is dependent on HNF-1.
Previous work identified four upstream cis-acting elements required for tissue-specific expression of the alpha-fetoprotein (AFP) gene: three distal enhancers and a promoter. To further define the role of the promoter in regulating AFP gene expression, segments of the region were tested for the ability to direct transcription of a reporter gene in transient expression assay. Experiments showed that the region within 250 base pairs of the start of transcription was sufficient to confer liver-specific transcription. DNase I footprinting and band shift assays indicated that the region between -130 and -100 was recognized by two factors, one of which was highly sequence specific and found only in hepatoma cells. Competition assays suggested that the liver-specific binding activity was HNF-1, previously identified by its binding to other liver-specific promoters. Mutation of the HNF-1 recognition site at -120 resulted in a significant reduction in transcription in transfection assays, suggesting a biological role for HNF-1 in the regulation of AFP expression.
Feuerman
M H
MH
Howard Hughes Medical Institute, Princeton University, New Jersey 08544.
Godbout
R
R
Ingram
R S
RS
Tilghman
S M
SM
D000818:Animals; D001483:Base Sequence; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000502:physiology; D003850:Deoxyribonuclease I; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000502:physiology; D051379:Mice; D009687:Nuclear Proteins / Q000378:metabolism; D009928:Organ Specificity; D011061:Poly A / Q000096:biosynthesis; D011401:Promoter Regions, Genetic / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012689:Sequence Homology, Nucleic Acid; D013937:Thymidine Kinase / Q000235:genetics; D014157:Transcription Factors / Q000502:physiology*; D000509:alpha-Fetoproteins / Q000235:genetics*
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D000509:alpha-Fetoproteins; D011061:Poly A; D013937:Thymidine Kinase; D003850:Deoxyribonuclease I