中文摘要：

选择绵羊胎儿期骨骼肌中表达稳定性高的内参基因,探讨AKT基因在绵羊妊娠中后期背最长肌中的发育性表达模式。以Texel和乌珠穆沁绵羊为研究对象,采用荧光定量PCR技术检测SDHC、YWHAB、RPLPO、RPS18、B2M 5个内参基因的mR-NA表达水平,同时检测AKT基因mRNA丰度在其胎儿期70、85、100、120和135 d间的表达变化,并分析其在品种间和不同生长阶段间的表达差异及其对肌肉生长发育的影响。5个内参基因的定量结果经GeNorm程序统计学分析处理,表达稳定性由高到低排序为RPS18〉RPLPO〉SDHC〉B2M〉YWHAB,确定用RPLPO、RPS18和SDHC 3个基因校正绵羊胎儿期不同生长阶段的目的基因表达量。在5个发育阶段中,两个品种绵羊胎儿AKT基因表达模式有一定差异,AKT表达量在Texel绵羊85和120 d时均有明显的增加,而在乌珠穆沁绵羊的100 d时出现1个表达峰,这与试验对两品种绵羊组织学分析的结果是一致的,进一步印证了Texel绵羊在85和120 d以及乌珠穆沁绵羊在100 d时存在肌发生波的推测。以上结果初步揭示绵羊妊娠中后期生长发育过程中AKT基因表达的发育性变化模式和品种差异,为深入研究AKT基因的作用机制提供了理论基础。

英文摘要：

To select the best stable reference genes and investigate the developmental expression patterns of AKT gene in sheep fetal muscle.Quantitative RT-PCR was conducted for B2M,GAPDH,RPLPO,RPS18 and SDHC and also applied to investigate AKT mRNA expression at the gestation of 70 d,85 d,100 d,120 d and 135 d in longissimus dorsi muscle of Texel and Ujumuqin sheep.The five reference genes of expression stability were analyzed by the GeNorm software,and the result showed that RPS18RPLPOSDHCB2MYWHAB.Furthermore,SDHC,RPLPO and RPS18 were identified as the most stable reference genes in the present study.In all the five stages,the expression patterns of AKT were dissimilar in the two sheep breeds.Strikingly,at the gestation of 85 d and 120 d,the expression of AKT reached their peak values in Texel,in contrast,in Ujumuqin it was at 100 d.These findings were consistent with our previous study which reflected the histological characteristics during the second half of gestation in the two sheep breeds,and this further verify that the surges in myofiber hyperplasia occurred at 85 d and 120 d in Texel sheep,whereas a unique proliferative surge appeared at 100 d in Ujumqin sheep.The results indicated that the transcript levels of AKT gene exhibited specific developmental expression changes between Texel and Ujumuqin sheep,and provided some data for further study on the effect of AKT gene.