miR208和miR499在巴马香猪骨骼肌肌纤维类型转化中的作用研究.docx

表达量(尸0．05)；分化早中期标志基因MyoG在C2C12及肌肉卫星细胞分 表达量(尸0．05)；分化早中期标志基因MyoG在C2C12及肌肉卫星细胞分 化过程中的表达量实验组和对照组无差异胗0．05)；C2C12及肌肉卫星细胞 分化过程中，AMPK的表达量实验组和对照组均无显著差异p0．05)；肌肉 卫星细胞中PGC．1 0【的表达水平显著上调伙O．05)。 6．C2C12和小鼠肌肉卫星细胞过表达miR．499后，肌纤维形态更细长； 在分化中后期显著上调MyHC I的表达(尸O．05)，显著下调MyHC IIB的 表达(尸o．05)；MyoG基因的表达量实验组和对照组无差异(尸O．05)； AMPK、PGC．1a的表达水平均显著上调(PO．05)。 综上所述，miR一208b和miR一499对氧化型肌纤维的形成有促进作用， 对酵解型肌纤维有抑制作用，可能通过调控AMPK、PGC．10t起作用。 关键词：巴马香猪肌纤维类型MyHC miR-208b miR-499 AMPK PGC．1仅 万方数据 EFFECT EFFECT OF miR．208b AND miR-499 ON SKELETAL MUSCLE FIBRE TYPES TRANSFORMATl0IN IN BAMA XIANG PIG ABSTRACT MicroRNAs，a class of evolutionarily conservative，non—coding small RNAs，play a key regulatory role in skeletal muscle development．The current study is to reveal the mechanism of good meat quality in Bama Xiang pig by ananlyzing the function of miR·-208b and miR··499 in the transformation of myofiber type． 1．Compared with other tissue，miR一208b and miR-499 were higher expression in longissimus dorsi，biceps femoris，and myocardium of Bama Xiang pig．Meanwhile，the result of longissimus dorsi at different development stages showed the expression of miR一208b and miR-499 continued to increase at embryonic stage，and decreased after birth． 2．During the development of longissimus dorsi in Bama Xiang pig，the expression of MyHC 1 was significantly decreased(PO．05)，the expression of MyHC IIA was no significant difference(胗O．05)，the expression of MyHC IIX was significantly increased(氏O．05)，and the expression of MyHC IIB was initially increased at E90．Meanwhile，the mRNA expression abundance of marker gene of oxidative fiber was higher than that of glycolytic fiber at embryonic stages，and reached the peak at E40；the mRNA expression abundance of marker gene of oxidative fiber was lower than that of glycolytic fiber at adulthood． 3．The expression of AMPK had positive correlation with the expression of MyHC I(r=O．956 1，尸O．05)at embryonic stage of Bama Xiang pig，and the expression of PGC—l a had negative correlation with the