Cloning And Analysis Of Partial Lipid-related Genes From Large Yellow Croaker

Culture environment's deterioration and other factors result in worse meat quality which affected economic benefit of Large yellow croaker aquaculture. Lipid-related genes including peroxisome proliferator-activated receptors(PPARs) play important role in meat quality and flavor. PPARs is activated by fatty acid and their eicosanoid metabolites and upon heterodimerization with the retinoid X receptor (Retinoid X receptor,RXR), they bind to specific peroxisome proliferator response elements (Peroxisome proliferator response element,PPRE) of numerous target genes including lipoprotein lipase(LPL),Uncoupling protein 2(UCP2),Liver-Fatty acid binding protein(L-FABP) and regulate them.Base on RT-PCR and real time PCR were used to clone and analyse the six genes of PPARα,PPARβ,PPARγ,LPL and UCP2 from large yellow croaker.The main results are reported as follow: (1) The full length cDNA of PPARαcontained 1601bp, the entire ORF 1437bp codes 478 amino acid with an estimated molecular mass of 53.3962kDa;the full length cDNA of PPARβcontained 1759bp,the entire ORF 1377bp codes 458amino acid with an estimated molecular mass of 50.9559kDa;the full length cDNA of PPARγcontained 1815bp,the entire ORF 1569bp codes 522 amino acid with an estimated molecular mass of 59.1071kDa;the full length cDNA of LPL contained 1957bp, the entire ORF 1545bp codes 514 amino acid with an estimated molecular mass of 58.1425kDa;the full length cDNA of UCP2 contained 1478bp, the entire ORF 939bp codes 312 amino acid with an estimated molecular mass of 33.526kDa;(2)We obtained PPAR three isotypes 1307bp(PPARα) including 4 exons and 3 introns;2986bp(PPARβ)including 6 exons and 5 introns,1133bp(PPARγ)including partial 2 exons and 1 intron; 2380bp and 1402bp (LPL) both including 4 exons and 3 introns , and 1473bp(UCP2) including 6 exons and 5 introns;(3) All PPAR three isotypes express highest in liver, PPARαexpresses higher in brain and heart. PPARβexpresses higher in liver,brain,gonad and gill, PPARγexpresses higher in heart, stomach, intestine. LPL also express in all tissues, but highest in liver and muscle, UCP2 expresses highest in heart, other tissues express unconspicuously. (4) After feeding fish oil with different concentration, the analysis of LPL mRNA tissue expression in some tissues shows that: 1) The more fish oil concentration, the lowest tissue expression in brain. 2) The feed (4% fish oil) can decrease LPL mRNA tissue expression in intestine, but The feed (8% fish oil) has the contrary. 3) The feed include fish oil can significantly increase LPL mRNA tissue expression in liver, then decrease gradually. 3) The feed including 4% and 8% fish oil can increase LPL mRNA tissue expression in muscle.