Cloning and characterization of lipoprotein lipase (LPL) and the effects of dietary lipid levels on the expression of LPL in the redlip mullet (<italic>Liza haematocheila)</italic>.

Abstract: The genetic improvement of redlip mullet <italic>Liza haematocheila</italic> through breeding programmes is of interest for this important aquaculture species. Lipoprotein lipase (LPL) is a key enzyme in lipid deposition and metabolism. The purpose of this study was to investigate the nutritional regulation of LPL in redlip mullet. We cloned and identified the LPL gene, determined LPL gene expression in various tissues, and examined the effect of dietary lipid level on hepatic LPL gene expression. The LPL gene of redlip mullet <italic>Liza haematocheila</italic> (L.hLPL) was 2,395 bp in length and encoded 516 amino acids. Sequence analysis showed that L.hLPL shared 61%–90.3% identity with LPLs in other species. Expression patterns of hepatic L.hLPL were studied in redlip mullet fed diets containing 2.0, 4.8, 7.5, 9.8, 12.0 or 14.6 g/kg, crude fat for 60 days by real‐time quantitative PCR. The abundance of LPL mRNA in hepatic tissue increased with the increase in dietary fat. The expression L.hLPL mRNA was significantly higher in the groups fed diets with 14.6 and 12.0 g/kg fat than in the other groups (<italic>p </italic><<italic> </italic>.05). Gene expression was significantly higher in the abdominal fat of redlip mullet (<italic>p </italic><<italic> </italic>.05) compared with other tissues. In conclusion, a high fat diet (9.79–14.59 g/kg) induces L.hLPL expression in abdominal fat. [ABSTRACT FROM AUTHOR]