Hormonal and nutritional regulation of muscle carnitine palmitoyltransferase I gene expression in vivo.
Transgenic mice carrying the human heart muscle carnitine palmitoyltransferase I (M-CPTI) gene fused to a CAT reporter gene were generated to study the regulation of M-CPTI gene expression. When the mice were fasted for 48 h, CAT activity and mRNA levels increased by more than 2-fold in heart and skeletal muscle, but not liver or kidney. In the diabetic transgenic mice, there was a 2- to 3-fold increase in CAT activity and CAT mRNA levels in heart and skeletal muscle which upon insulin administration reverted to that observed with the control insulin sufficient transgenic mice. Feeding a high fat diet increased CAT activity and mRNA levels by 2- to 4-fold in heart and skeletal muscle of the transgenic mice compared to the control transgenic mice on regular diet. Overall, the M-CPTI promoter was found to be necessary for the tissue-specific hormonal and dietary regulation of the gene expression.
Department of Environmental and Biomolecular Systems, OGI School of Science and Engineering, Oregon Health and Science University, Beaverton, OR 97006-8921, USA.
Hong Yan
HY
Liu
Guolu
G
Zheng
Hongfa
H
Zhu
Gebre
G
Woldegiorgis
D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D004041:Dietary Fats / Q000378:metabolism*; D005215:Fasting / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D006728:Hormones / Q000378:metabolism*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000378:metabolism*; D009928:Organ Specificity; D014018:Tissue Distribution
D004041:Dietary Fats; D006728:Hormones; D002334:Carnitine O-Palmitoyltransferase