PGC1α molecular characterization and its responsiveness to nutrient restriction, carbohydrate-enriched diets and glucose loadings in blunt snout bream (Megalobrama amblycephala)

To explore the mechanism of peroxisome proliferator activated receptor γ coactivator 1α (PGC1α) in the glucose metabolism of blunt snout bream Megalobrama amblycephala, the partial cDNA of PGC1α was cloned, and the transcriptional response of this gene to nutrient restriction, carbohydrate-enriched diets and glucose loadings were investigated. The partial cDNA was 2566 bp with an open reading frame of 1 404 bp encoding 467 amino acids, and compared to Ctenopharyngodon idellus, it showed 96.79% homology. The mRNA levels of PGC1α in the brain and liver were significantly increased during 10 days of fasting, and then decreased to normal level after refeeding 1 h. The high-carbohydrate diet significantly decreased the mRNA levels of PGC1α in the brain and liver. In addition, the mRNA levels of PGC1α in the brain and liver both decreased significantly during the first 2 h, then returned to the basal value at 12 h. The results indicated that PGC1α plays an important role in glucose metabolism in M. amblycephala. The results obtained here will provide the theoretical foundation for completing the research of PGC1α functions involving the regulation of glucose homeostasis in fish.