Identification of full-length cDNA sequences for three development-relevant genes from yellow catfish Pelteobagrus fulvidraco and their transcriptional responses to high fat diet.

The goal of this study was to clone and characterize complete cDNA sequences of three important development-relevant genes of yellow catfish Pelteobagrus fulvidraco, including lrp6, sox9a1 and fgfr2c, and explore their transcriptional responses in several tissues of P. fulvidraco to high fat diet. The predicted amino acid sequences of P. fulvidraco Lrp6, Sox9a1 and Fgfr2c contained all of the conserved structural features that were characteristic of these genes in other species, including YWTD domains, EGF-like repeats, LDLR ligand binding repeats, PPSP repeats motifs, HMG box, TA-binding functional domain, Ig I-III and PTK I-II. The mRNAs of the three genes were expressed in various tissues, but their mRNA levels varied among tissues. Compared to the control, high fat diet tended to down-regulate the mRNA expression of sox9a1 and fgfr2c in mesenteric fat, liver and ovary, and up-regulate their mRNA levels in muscle and kidney; in contrast, high fat diet down-regulated lrp6 mRNA levels in the ovary and muscle, but had no significant effects on lrp6 mRNA expression in mesenteric fat, liver and kidney. Our findings provide the first data about their expression responses to dietary lipid in teleosts and reinforce the multiple functions at the molecular level.