Regulation of hepatic stearoyl-CoA desaturase gene 1 by vitamin A.
The effect of vitamin A supplementation on stearoyl-CoA desaturase gene 1 expression in mouse liver was characterized. Normal BALB/c mice were fed 0.01% and 0.1% retinol palmitate as components of nonpurified diets. This treatment resulted in a 3-fold and a 7-fold induction of SCD1 mRNA levels, respectively, as determined by RNase protection analysis. Vitamin A-deficient animals were also fed diets containing 0.01% and 0.1% retinol palmitate, resulting in a similar pattern of SCD1 mRNA induction. Fatty acid synthase and beta-actin mRNA levels did not respond consistently or significantly to retinoic acid treatment. Dietary and hormonal studies were carried out to investigate the role of the retinoid X receptor in the regulation of SCD1 by type II steroid hormones. A receptor-saturating dose of thyroid hormone, triiodothyronine, repressed vitamin A-elevated SCD1 mRNA levels in vivo. Peroxisome proliferator-elevated SCD1 mRNA levels were unaffected by administration of thyroid hormone. This suggests that the retinoic acid receptor transcriptionally regulates SCD1 through a traditional mechanism of heterodimerization with the retinoid X receptor.
Miller
C W
CW
Department of Biochemistry, University of Wisconsin-Madison 53706, USA.
Waters
K M
KM
Ntambi
J M
JM
D000199:Actins / Q000235:genetics; D000818:Animals; D002994:Clofibrate / Q000494:pharmacology; D004224:Diterpenes; D004305:Dose-Response Relationship, Drug; D064429:Fatty Acid Synthases / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008830:Microbodies / Q000187:drug effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D047488:Retinoid X Receptors; D000084562:Retinyl Esters; D013230:Stearoyl-CoA Desaturase / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism; D014284:Triiodothyronine / Q000494:pharmacology; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000494:pharmacology; D014802:Vitamin A Deficiency / Q000201:enzymology
D000199:Actins; D004224:Diterpenes; D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; D047488:Retinoid X Receptors; D000084562:Retinyl Esters; D014157:Transcription Factors; D014284:Triiodothyronine; D014801:Vitamin A; C014794:retinol palmitate; D013230:Stearoyl-CoA Desaturase; D064429:Fatty Acid Synthases; D002994:Clofibrate