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.
Liu
Hong Yan
HY
Department of Environmental and Biomolecular Systems, OGI School of Science and Engineering, Oregon Health and Science University, Beaverton, OR 97006-8921, USA.
Zheng
Guolu
G
Zhu
Hongfa
H
Woldegiorgis
Gebre
G
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