Cloning Of The Important Immune Genes And Effects Of Dietary Vitamin D₃ On The Genes Expression In Yellow Catfish?Pelteobagrus Fulvidraco?

The current research studied the effects of dietary vitamin D₃ on the expression of three immune related genes in three tissues of Pelteobagrus fulvidraco after 8-week growth trial.The results showed that dietary vitamin D₃ has important effects on the expression of immune genes,i.e.AP1M1,MHC-II,IFP35.The experiment was carried out for 8 weeks with initial body weight around 2g in two different treatments.The control group was designed with 0 IU / kg of vitamin D₃ while the treatment group was supplemented with 5000 IU / kg of vitamin D₃.By the end of the growth trial,the small intestine,kidney,and liver of the control group and the treatment group were sampled for measuring the effects of dietary vitamin D₃.At the same time,the intestine,kidney,liver,fin,muscle,skin,gill,brain,head kidney of fish without vitamin D₃ treatment were sampled to analyzed the tissue expression of AP1M1,MHC-II,IFP35 genes by real-time PCR.The major results are as follows:?1?The full length of c DNA of AP1M1,MHC-II,IFP35 genes were obtained by RACE method.The length of AP1M1 gene was 1814 bp,and the length of ORF?open reading frame?was 822 bp,encoding 273 amino acids,5'UTR?5 'untranslated region?121 bp,3'UTR?3' untranslated region?871 bp.The MHC-II gene has a length of 1074 bp,with a 708 bp ORF,which encodes 236 amino acids,5'UTR?5'-untranslated region?78 bp,3'UTR?3 'untranslated region?259 bp.The length of IFP35 gene was 1810 bp,with a 1128 bp ORF,encoding 376 amino acids,5'UTR?5 'untranslated region?97 bp,3'UTR?3' untranslated region?585 bp.?2?We cloned the c DNA length of AP1M1,MHC-II,IFP35 c DNA by RACE?rapid-amplification of c DNA ends?.The bioinformatics analysis showed that amino acid sequence of the ORF of AP1M1 gene in Pelteobagrus fulvidraco had the similarity of 91.6% with channel catfish?Ictalurus punctatus?,the similarity of 84.7% with Poecilia formosa.The amino acid sequence of the ORF of MHC-II gene in Pelteobagrus fulvidraco had a similarity of 69.5% with Leiocassis longirostris and the similarity of 50.4% with Cyprinus carpio.The amino acid sequence of ORF of IFP35 gene in Pelteobagrus fulvidraco had a similarity of 79.0% with Ictalurus punctatus,and had a similarity of 50.4% with Salmon salmon.?3?The tissue expression of AP1M1 and IFP35 genes were detected in all the analyzed tissues,while MHC-II gene is only expressed in small intestine,fin,muscle,liver and gill.?4?AP1M1 was expressed in small intestine,kidney and liver of both the control group and the vitamin D₃ treatment group.However,dietary vitamin D₃ significantly up-regulated AP1M1 expression in liver?P<0.05?.MHC-II gene was not expressed in small intestine,kidney and liver in the control group but dietary vitamin D₃ significantly up-regulated MHC-II gene expression in small intestine and kideny?P <0.05?.The IFP35 gene was expressed in small intestine,kidney and liver in both the control group and the vitamin D₃ treatment group.However,dietary vitamin D₃ significantly up-regulated IFP35 gene expression in liver and kidney.?P <0.05?.This study indicated that dietary vitamin D₃ can affect the expression of immune related genes,i.e.AP1M1,MHC-II,IFP35,in liver,kidney and small intestine of yellow catfish.This result revealed that dietary vitamin D₃ can serve as immune stimulant in addition to its traditional function in maintaining calcium and phosphate homeostasis.The current study provided useful information to further research the immune function of dietary vitamin D₃ in fish and laid foundation for develop immune-enhanced fish feed.