Studies on transcriptional regulation of Cyp3a16 gene in mouse livers by application of direct DNA injection method.
CYP3A16 is expressed in the mouse liver specifically during a fetal and puberty life. Functional regions responsible for the transcriptional regulation of the Cyp3a16 gene were identified by an in vivo direct DNA injection into mouse livers followed by a luciferase assay. The results of the deletion analysis of a 5'-flanking sequence suggested the existence of an adult-specific repressor(s) interacting with the Cyp3a16 gene. In addition, a positive regulatory element was assumed to be present in a region from -146 to -56 of the Cyp3a16 gene. A hepatocyte nuclear factor 4 (HNF-4)-binding consensus sequence was found in this region. In fact, HNF-4alpha bound to this sequence as evidenced by a gel mobility shift assay. The role of the HNF-4-binding sequence was further examined by an introduction of mutations in this sequence. The introduction of the mutations resulted in a reduced activity of a luciferase in the assay. These results obtained by an application of the direct DNA injection method suggest that the HNF-4alpha activates the transcription of the Cyp3a16 gene in vivo.
Nakayama
K
K
Laboratory of Drug Metabolism, Graduate School of Pharmaceutical Sciences, Hokkaido University, N12W6, Kita-ku, Sapporo, Hokkaido 060-0812, Japan.
Sudo
Y
Y
Sasaki
Y
Y
Iwata
H
H
Takahashi
M
M
Kamataki
T
T
D000375:Aging; D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D001665:Binding Sites; D051544:Cytochrome P-450 CYP3A; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D004247:DNA / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D017930:Genes, Reporter; D051557:Hepatocyte Nuclear Factor 4; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008845:Microinjections; D010089:Oxidoreductases, N-Demethylating / Q000235:genetics*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics*
D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins; D051557:Hepatocyte Nuclear Factor 4; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; C501970:Tcfl4 protein, mouse; D014157:Transcription Factors; D004247:DNA; D003577:Cytochrome P-450 Enzyme System; D008156:Luciferases; D001189:Aryl Hydrocarbon Hydroxylases; D051544:Cytochrome P-450 CYP3A; D010089:Oxidoreductases, N-Demethylating