ppar regulates lipid catabolism by mediating acox and cpt-1 genes in Scophthalmus maximus under heat stress

Peroxisome proliferator-activated receptor beta (ppar beta) is a key gene-regulating lipid metabolism pathway, but its function in turbot remains unclear. In this study, the CDS of ppar beta was cloned from kidney for the first time. The CDS sequence length was 1533 bp encoding 510 amino acids. Structural analysis showed that the ppar beta protein contained a C4 zinc finger and HOLI domain, suggesting that the ppar beta gene of turbot has high homology with the PPAR gene of other species. The high expression patterns of ppar beta, acox, and cpt-1 at high temperatures, as shown through qPCR, indicated that high temperatures activated the transcriptional activity of ppar beta and increased the activity of the acox and cpt-1 genes. The expression of acox and cpt-1 was significantly inhibited when ppar beta was downregulated using RNAi technology and inhibitor treatments, suggesting that ppar beta positively regulated acox and cpt-1 expression at high temperatures and, thus, modulates lipid catabolism activity. These results demonstrate that ppar beta is involved in the regulation of lipid metabolism at high temperatures and expand a new perspective for studying the regulation of lipid metabolism in stress environments of teleost.