Study On The Regulation Of FNDC5 On Porcine Fat Deposition And Its Mechanism

Fat deposition is closely related to lean meat percentage in pigs.Type Ⅲ domain containing protein 5(FNDC5)plays an important role in fat deposition,it can be cut to form Irisin to promote fat thermogenesis,burn fat.However,The mechanism of FNDC5 on fat deposition is still unclear.In this study is explored the regulatory effect of FNDC5 on adipogenic differentiation,which can provide basic data for functional studies of FNDC5.In this study,the CDS sequence of porcine FNDC5 gene was obtained by PCR plification,and the basic structure of FNDC5 was analyzed by biological informatics.The expression pattern of FNDC5 was detected by q RT-PCR and Western blotting in Mashen pigs and Large White pigs.FNDC5 overexpression and interference vectors were constructed and transfected into C3H10T1/2 cells and porcine primary preadipocytes by lentivirus respectively.Then the expression of key adipogenic genes was detected by q RT-PCR and the content of lipid droplets was detected by oil red O staining.At the same time,the expression levels of extracellular regulated kinase1 1/2(ERK1/2)and P-ERK1/2 were detected by Western blotting.The results showed that the CDS of porcine FNDC5 was successfully obtained,which was 843 bp in length and encoding 280 amino acids.The expression level of FNDC5 of Mashen pigs the expression level in abdominal fat was higher than that in back subcutaneous fat.The expression level of FNDC5 in subcutaneous adipose tissue of Mashen pigs was significantly higher than that of Large White pigs.After overexpressing FNDC5 in C3H10T1/2 cells,the expression of adipogenic key genes,including peroxisome proliferator-activated receptorγ(PPARγ)(P<0.01),fatty acid binding protein 4(FABP4)(P<0.01),CCAAT enhancer binding protein alpha(C/EBPα)(P<0.01)and CCAAT enhancer binding protein beta(C/EBPβ)(P<0.05),were significantly decreased.Meanwhile,the content of lipid droplets and P-ERK1/2 were significantly decreased(P<0.05).After interference with FNDC5 in C3H10T1/2 cells,the expression levels of the above-mentioned key adipogenic genes were significantly increased(P<0.01),and the content of lipid droplets and P-ERK1/2 was significantly increased(P<0.05).After the overexpression of FNDC5 in porcine primary preadipocytes,the expression levels of PPARγ(P<0.01),FABP4(P<0.01),C/EBPα(P<0.01)and C/EBPβ(P<0.05)were significantly increased.The content of lipid droplets was significantly increased,but the content of P-ERK1/2 was not significantly changed.After interference with FNDC5 in porcine primary preadipocytes,the expression levels of PPARγ,C/EBPβ,FABP4 and C/EBPα were significantly decreased(P<0.05).The content of lipid droplets was significantly decreased,and the content of P-ERK1/2 was not changed.In conclusion,the CDS sequence of porcine FNDC5 was successfully cloned,the expression level of FNDC5 in subcutaneous adipose tissue of Mashen pigs is significantly higher than that of Large White pigs.The regulation effect of FNDC5 on adipogenic differentiation of C3H10T1/2 cells and porcine primary preadipocytes was not consistent.FNDC5 inhibited the adipogenic differentiation of C3H10T1/2 cells,but promoted the adipogenic differentiation of porcine primary preadipocytes.The role and specific mechanism of FNDC5 in regulating fat deposition were explored.The results of this study provided a theoretical basis for the function of FNDC5 in regulating fat development.