The Structure Variation Of MSTN Affects The Growth Of Bovine Muscle

MSTN is a member of the transforming growth factor-beta(TGF-?)superfamily,which inhibits the growth of muscle fibers.Previous researches reported that mutations of MSTN indue double-muscling phenotype.In the present study,the genome of double-muscling bovine was sequenced and MSTN gene was muted.Bioinformatics methods were taken to evaluate the change of structure on mRNA and protein.In vitro transfection of MSTN indicated that the muscle cells that wild type MSTN has significant effects on growth suppression than the mutated MSTN.Quantitive real-time PCR and Wesstern Blotting were performed to detect the expression level of MSTN mRNA and protein.The results were showed that:(1)The mutated site of MSTN was at 952bp-962 bp,with a deletion of 11 bp of TGAACACTCCA and alteration of amino acid sequence.(2)The mutation of MSTN gene caused the stuctural change of its mRNA and protein,which affected the function of normal MSTN protein.(3)Quantitive real-time PCR and Wesstern Blotting proved that there was significant difference more MSTN expression of wild-type bovine over the mutated one.(4)The iCELLigence method indicated that the mutation of the MSTN gene had negative impact on the growth muscle cells,therefore promoting the process of differentiation and myotube formation.In conclusion,the reason for the appearance of double-muscling phenotype includes the structural alteration and the expression level alteration of mRNA and protein.