中文摘要：

为克隆鱤（Elopichthys barnbusa）的胰岛素样生长因子1（IGF1）全长cDNA和启动子序列及明确其组织表达特征，采用反转录PCR（RT—PCR）、cDNA末端快速扩增（RACE）和染色体步移等技术，从鱤肌肉中获得了IGF1基因的全长cDNA（844bp）和上游启动子部分序列（627bp）。结果表明：IGF1基因包含218bp的5’端非翻译区、140bp的3’端非翻译区和486bp的开放性阅读框（ORF），编码161个氨基酸，包含前44个氨基酸残基为信号肽、70个氨基酸残基的4个功能结构域和C端47个氨基酸残基的延伸肽结构域。启动子无TATA框，但含有一成肌分化抗原（MyoD）结合位点。氨基酸同源性和系统发育分析发现，鱤IGF1与鲤形目其他鱼类的同源性较高（94．41％～99．38％），亲缘关系最近。半定量RT—PCR结果显示，IGF1在鱤的肝脏中表达最高，而心脏中未见其明显表达。该研究为明确IGF1参与鱤生长发育的机制研究及其在鳃的繁殖育种中的应用奠定了基础。

英文摘要：

The objective of the present research was to clone full length IGF1 cDNA sequence and to determine its expression in various tissues from Elopichthys bambusa. Reverse transcription PCR （RT-PCR）, rapid-amplification of cDNA ends （RACE） were used to amplify full-length of IGF1 cDNA. Semi-quantatative RT-PCR was used to compare IGF1 gene expression levels from various tissues. A full-length of IGF1 cDNA sequence in E. bambusa was obtained, which included a complete open reading frame （ORF） of 486 bp, a 5＇-untranslated region of 218 bp, and a 3＇-untranslated region of 140 bp. The putative peptide contained a signal sequence of 44 amino acid, a mature peptide of 70 amino acid in the functional domain, and an extended carboxyl-terminal peptide of 47 amino acid in domain E. IGF1 from E. bambusa showed an amino acid identity of 94.41%- 99.38% with that from Cypriniformes. The phylogenetic analyses showed that IGF1 from E. bambusa had closest relationship with other fishes in Cypriniformes. Furthermore, IGF1 mRNA levels were highest in liver but relatively low or absent in heart. A part of IGF1 promoter sequence was cloned by using Genome Walking, which included a Myogenic Differentiation Antigen （Myo D）. But there was not a consensus TATA box a bout 5＇ to the start site of transcription in IGF1. These results indicated the IGF1 promoter differed to the classic promoter. These findings provide clue for IGF1 involvement in the growth and development of E. bambusa and are potential basis for its effective breeding and propagation.