稀有鮈鲫铜蓝蛋白基因 cDNA 克隆及组织表达分析

铜蓝蛋白(Ceruloplasmin,Cp)是一种重要的铜转运蛋白,合成于肝脏并参与生物体铁的代谢,在医学上是各种炎症、感染、中毒及癌症疾病的标志性蛋白.铜蓝蛋白的研究已在多种真骨鱼类中被报道,文中第一次在稀有鮈鲫(Gobiocypris rarus)中报道此基因.采用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)克隆了稀有鮈鲫铜蓝蛋白基因,使用荧光定量PCR的方法构建了该基因组织表达谱.序列分析表明稀有鮈鲫铜蓝蛋白基因包含3 264bp全长编码序列,该序列编码1 087个氨基酸,其核苷酸和氨基酸序列与斑马鱼同源性最高(分别为88.1%和90.3%).理论相对分子质量和等电点分别为124 429.1D和6.41.荧光定量PCR检测表明该基因在肝脏和脾脏中相对表达量最高,在肌肉和鳃中相对表达量最低.使用氨基酸序列进行蛋白结构保守域分析,结果表明铜蓝蛋白基因在脊椎动物中是相对保守的,推测其功能也与其他物种相似.这为进一步研究稀有鮈鲫该基因的功能及其应用奠定了基础.

On Cloning,Sequence Analysis and Tissue Expression of Ceruloplasmin Gene in Rare Gudgeon

Ceruloplasmin (Cp) ,which is the major copper-carrying protein synthesized in the liver ,plays a role in iron metabolism .It is a marker protein for inflammation ,infection ,poisoning and cancer .The Cp gene has been reported in several teleosts and here the gene in rare gudgeon (Gobiocy p ris rarus) has been first characterized . In this study , the Cp gene has been cloned by rapid amplification of cDNA ends (RACE) .Real-time PCR has been performed to demonstrate the expression pattern in different tissues . The CDS of Cp gene is 3 264 bp long ,which encodes 1 087 amino acids .BLAST result indicates that the most similar homologue of rare gudgeon Cp is from zebrafish ,with a homology of 88 .1% (DNA ) and 90 .3% (amino acid) .The predicted relative molecular mass of the protein is 124 429.1 D with an estimated PI of 6 .41 .Real-time PCR show s that liver and spleen tissues have the highest level of expression of Cp gene ,whereas its lowest expression level has been detected in muscle and gill .Conserved domain analysis indicates that its sequence and function are conserved among vertebrates .This provides a powerful tool for future study on gene function and its possible application .