Abstract：The aim of this study was to obtain the complete coding region sequence (CDS) and explore its expression in different tissues of the myocyte-specific enhancer binding factor 2A gene (MEF2A) in duck(Anas platyrhynchos). In this study, Xingyi ducks (A. platyrhynchos) were chosen to the samples for the coding region cloning of MEF2A gene by the Real-time fluorescent quantitative PCR (qRT-PCR) and A/T cloning technology, and we obtained the pGEM-T-MEF2A recombinant plasmid successfully, and the mRNA expression of MEF2A gene in different tissues by qRT-PCR was also researched. The results showed that the coding sequence of the MEF2A gene in Xingyi duck was successfully cloned, the length of the open reading frame sequence was 1 479 bp, and 5 SNPs were found. The qRT-PCR results showed that the MEF2A gene had the similar expression mode in pectoral, thigh muscle and heart. They all had the same trend that from rise to decline, but there was different expression in gender. The expression amount of the female duck in myocardium showed that, it decreased from 0 to 30 d age, then it rised from 30 to 90 d, it decreased again after 90 d, whereas the expression of the myocardium in drake was keeping descending. The expression of pectoral in different sex duck had the same pattern, it decreased from 0 to 30 d age, and it began rised from age of 30 d, it reached maximum value at 120 d, after that, it decreased again.The expression amount of thigh muscle and myocardium were similar, they were both keeping the downward trend between 0 and 150 d age. The expression amount of thigh muscle in female duck was from the decline to a little rise, and then keeping the downward state. Although the MEF2A gene existed expression difference in different sex, on the whole, the expression of the myocardium and skeletal muscle was higher than that in smooth muscle. The results of these experiment showed that the MEF2A mRNA could be expressed in different tissue of Xingyi duck, and it existed some difference. And this study also found that the expression trend between female and male ducks in different tissues of the same growth stage was not consistent, moreover, it also existed significant expression difference in different growth stage of the same tissues. Therefore, this study provides the basis for the construction of prokaryotic expression vector and tissue expression profile of MEF2A gene in the follow-up research.
