猪IGF-1 E肽在不同体型猪中的表达差异

Differential Expressions of Porcine IGF-1 E Peptides in Pigs of Different Body Sizes

IGF-1基因与小型猪的"比例性矮小"相关,且IGF-1基因结构复杂,其C端由于可变剪接可产生3种E肽,分别为Ea、Eb和Ec。为分析IGF-1的3种E肽(Ea、Eb、Ec)表达量对猪体型大小的影响,选取大白猪和巴马香猪作为大型、小型猪样本。通过PCR方法在大小型猪中鉴定3种E肽,然后采用实时荧光定量PCR方法检测3种E肽在大小型猪7种组织中的相对表达量。结果表明:在大小型猪中均存在3种类型的E肽,其中,Ea在小型猪中表达量显著高于大型猪(P<0.05),在肝脏、心脏、肺脏和脾脏组织中差异极显著(P<0.01),但在软骨组织呈相反结果;Eb在小型猪的肝脏和软骨组织中表达量显著(P<0.05)或极显著高于大型猪(P<0.01),但在心脏组织中表现相反,且在其他组织中表达量较低;Ec在大小型猪中的表达情况与Ea相似,但在软骨组织中差异不显著(P>0.05)。3种E肽分析显示,Ec表达量最高,Ea表达量次之,Eb表达量最低。这说明,小型猪中Ea与Ec高表达不促进机体器官重量,也不影响小型猪体长的增长。

IGF-1 gene is thought to be related to the "proportional dwarfism" of minipigs, the structure of which is complex and the C-terminal of which can produce three types of E-peptides(Ea, Eb and Ec) due to variable splicing. In this study, Large White and Bama pigs were chosen as representatives of large and small pigs. Identification and relative expression were detected in large and small pigs by PCR and real-time fluorescent quantitative PCR. The results showed that there were 3 types of E peptides in large and small pigs, among which Ea was highly expressed in minipigs(P<0.05), especially in liver, heart, lung and spleen tissues;Eb was in the liver of minipigs. The expression level in cartilage tissue was higher, but in heart tissue, the expression level was higher in large pigs, while the expression level in other tissues was lower;Ec was similar to Ea in large and small pigs. Compared with the three E peptides, the expression level of Ec was the highest, the expression level of Ea was the second, and the expression level of Eb was the lowest. The results showed that the high expression of Ea and Ec was not conducive to the growth of pig body length, which provides a more comprehensive theoretical basis for the analysis of the application of small pigs and small pigs.