小尾寒羊不同生长阶段肌球蛋白与肌球蛋白重链相关基因的变化

Changes in the Expression of Myosin and Myosin Heavy Chain Isoform Genes during the Growth of Small Tailed Han Sheep

为研究不同生长阶段小尾寒羊股二头肌中肌球蛋白与肌球蛋白重链(myosin heavy chain,MyHC)异构体相关基因的内在变化规律,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳与聚合酶链式反应(polymerase chain reaction,PCR)技术对自然放牧条件下1~18月龄小尾寒羊股二头肌MyHC进行分离,测定其相关基因的相对表达量。结果表明:小尾寒羊股二头肌中肌球蛋白含量总体呈现上升趋势,9月龄达到最大值;MyHCⅠ基因相对表达量随着月龄的增加呈现下降趋势,MyHCⅡa基因相对表达量与月龄呈正相关,MyHCⅡb基因相对表达量总体呈现先减后增的趋势,MyHCⅡx基因相对表达量9月龄最低,12月龄最高;MyHCⅠ基因相对表达量在6~9月龄变化较大,说明6~9月龄生长变化较快,9~12月龄变化较小,说明9~12月龄生长缓慢。

We carried out this study in order to explore the pattern of change in the expression of the myosin and myosin heavy chain(MyHC)isoforms genes in Small Tailed Han sheep at different growth stages.MyHC isoforms from the Biceps femoris of naturally grazed Small Tailed Han sheep aged between 1 and 18 months were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE).The relative gene expression level of MyHC was investigated by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR).The content of myosin in the Biceps femoris showed an upward trend with age up to 9 months.The relative expression level of the MyHCI gene showed a downward trend with age.The relative expression level of the MyHCIIa gene was positively correlated with age.The expression level of the MyHCIIb gene first decreased and then increased.The expression of the MyHCIx gene was the lowest and highest at 9 and 12 months of age,respectively.The expression of the MyHCI changed greatly between 6 and 9 months of age,indicating a rapid growth rate,but changed little between 9 and 12 months,indicating a slow growth rate.