山羊IGFBP-1基因的克隆及其mRNA丰度在多种组织中的发育性变化

Molecular Cloning and mRNA Developmental Expression of IGFBP-1 Gene in Goat Different Tissues

本研究旨在探讨胰岛素样生长因子结合蛋白1(Insulin-like growth factor-binding protein 1,IGFBP-1)基因在山羊出生后不同组织的发育性表达模式。在出生后0、15、30、60、90和120d共屠宰36只南江黄羊羔羊(公、母羔羊各18只),取心脏、肝脏、脾脏、肺脏、背最长肌、半膜肌、臂三头肌和股二头肌样品以抽提RNA,进行克隆及荧光定量PCR分析。山羊IGFBP-1基因的ORF(Open reading frame)长792bp,共编码263个氨基酸,其核苷酸和氨基酸序列相似性在反刍动物(牛、绵羊)之间远大于其它物种。羔羊肝脏IGFBP-1mRNA表达量最高(P<0.01);肺脏、脾脏、心脏表达水平中等;肌肉中最低且在4种肌肉间表达差异不显著(P>0.05)。出生后尤其是60d内羔羊IGFBP-1mRNA丰度变化很大,且明显呈现持续下降(肝脏)、先升后降(心脏)以及下降-上升-下降(脾脏、肺脏和肌肉)3种模式的变化。结果提示,IGFBP-1基因CDS区在物种间保守性较强,肝脏是山羊合成IGFBP-1mRNA的主要部位,IGFBP-1基因在出生后羔羊的早期生长中发挥着重要的作用且其mRNA发育性表达模式具有组织器官特异性。

The objective of the present study was to investigate the developmental expression patterns of insulin-like growth factor-binding protein 1（IGFBP-1） gene in different tissues of postnatal goat.The samples of heart,liver,spleen,lung,longissimus dorsi,semimembranosus,m.triceps brachii and biceps muscle of thigh were collected from a total of 36（18 males and 18 females,respectively） Nanjiang Mongolian Grazelle at the ages of 0,15,30,60,90 and 120 days after birth.The CDS and ontogeny mRNA levels of IGFBP-1 were obtained and analyzed by real-time fluorescence quantitative RT-PCR.The size of IGFBP-1 ORF was 792 bp encoding 263 amino acid residues,and displayed higher nucleotide/amino acid sequence identities in ruminants compared to others.The IGFBP-1 mRNA levels in liver were most abundant（P〈0.01）,medium in lung,spleen and heart,and the lowest in the muscles and had no significant difference among themselves（P〉0.05）.In addition,three expression patterns of IGFBP-1 mRNA during postnatal growth from birth to day 60 were found： consistent down-expression（liver）,fluctuating expression as up-down（heart） or as down-up-down（spleen,lung and muscles）.These results indicate that IGFBP-1 gene is highly conservative among species,and liver is the main expression site of goat IGFBP-1 mRNA and IGFBP-1 play an important role in early growth of postnatal goat,and it is expressed in a developmental-tissue-dependent manner.