鸡生长发育早期骨骼肌IGF1R mRNA表达规律研究

以生长速度不同的花山麻鸡和清远麻鸡为试验素材,采用实时荧光定量PCR方法检测鸡9、12、16、21胚龄(E9 d、E12 d、E16 d、E21 d)和出雏后7日龄(7 d)时胸肌和腿肌中IGF1R mRNA表达变化情况,并与肌肉质量进行相关性研究。结果发现,21胚龄时,花山麻鸡和清远麻鸡胸肌质量都出现了显著降低,腿肌质量持续增长。花山麻鸡胸肌IGF1R mRNA表达呈前高后低趋势,9胚龄时表达量最高,之后显著降低并维持在较低的水平,出雏后7日龄时表达量再次下降;清远麻鸡在胸肌中的表达则呈“波浪形”,9胚龄和16胚龄表达量升高,其他日龄表达量显著降低。腿肌中,花山麻鸡IGF1R mRNA表达量在16胚龄之后显著降低;清远麻鸡腿肌IGF1R mRNA表达呈依次递减模式,各时间点之间差异显著(P<0.05)。品种间各个时间点胸肌和腿肌IGF1R mRNA表达量均呈显著差异(P<0.05)。两个品种骨骼肌IGF1R mRNA表达与胸肌、腿肌质量均呈极显著相关(P<0.01)。以上结果初步揭示了生长发育早期不同品种鸡胸肌和腿肌IGF1R基因表达发育变化趋势和品种差异,为深入研究IGF1R基因在鸡肌肉发育中的调控机理提供基础资料。

Study on mRNA expression pattern of IGF-1R gene in chicken skeletal muscles during early development

In the present study, the Huashan and Qingyuan partridge chickens differing in growth rates were used as experimental materials,fluorescent real-time quantitative PCR (RT-PCR) was used to detect the mRNA expression pattern of IGF1R gene in pectoral and leg muscle of chickens on the embryonic days of 9, 12, 16, 21 and 7 days post-hatching. The results showed that pectoral muscle weight significantly decreased in the two breeds at the embryonic days 21, but leg muscle weigh significantly increased as time going. IGF1R mRNA expression tendency of pectoral muscle in Huashan partridge chickens were from the high to the low: the embryonic days 9 was an expression peak, and then the expression level significantly decreased and kept a low level and down-regulated in 7 days post-hatching again. IGF1R mRNA expression of pectoral muscle in Qingyuan partridge chickens were a wavy trend: the expression levels of IGF1R gene on pectorals at 9 and 16 embryo age were higher, others were significant down-regulated. In leg muscle, the expression levels of IGF1R gene were significant down-regulated after 16 embryo age in Huashan partridge chicken; the expression levels of IGF1R gene in Qingyuan partridge chickens were decreased gradually and there were significant differences among groups(P<0.05). The expression level of IGF1R gene in pectoral and leg muscles were significantly different between varieties at different time(P<0.05). The expression level of IGF1R gene were significantly correlated with the weight of pectoral and leg muscles, respectively (P<0.01). The above results were preliminarily revealed the development changes and difference of IGF1R gene expression in pectoral and leg muscles during early development of different breeds, provide basic data for further study on regulation mechanism of chicken muscle development.