Regulation of liver carnitine palmitoyltransferase I gene expression by hormones and fatty acids.

Centre de Recherche sur l'Endocrinologie Moléculaire et le Développement, UPR 1524 CNRS, 9 rue Jules Hetzel, 92190 Meudon, France.
Biochemical Society Transactions (Impact Factor: 3.24). 06/2001; 29(Pt 2):310-6. DOI: 10.1042/0300-5127:0290310
Source: PubMed

ABSTRACT This brief review focuses on the transcriptional regulation of liver carnitine palmitoyltransferase I (L-CPT I) by pancreatic and thyroid hormones and by long-chain fatty acids (LCFA). Both glucagon and 3,3',5-tri-iodothyronine (T(3)) enhanced the transcription of the gene encoding L-CPT I, whereas insulin had the opposite effect. Interestingly, the transcriptional effect of T(3) required, in addition to the thyroid-responsive element, the co-operation of a sequence located in the first intron of L-CPT I gene. Non-esterified fatty acids rather than acyl-CoA ester or intra-mitochondrial metabolite were responsible for the transcriptional effect on the gene encoding L-CPT I. It was shown that LCFA and peroxisome proliferators stimulated L-CPT I gene transcription by distinct mechanisms. Peroxisome proliferator stimulated L-CPT I gene transcription through a peroxisome-proliferator-responsive element (PPRE) located at -2846 bp, whereas LCFA induced L-CPT I gene transcription through a peroxisome-proliferator-activated receptor alpha (PPARalpha)-independent mechanism owing to a sequence located in the first intron of the gene.

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