松江鲈β-肌动蛋白基因全长cDNA的克隆和序列分析

目的]获得松江鲈β-肌动蛋白基因cDNA全长序列,并检测松江鲈β-肌动蛋白在组织中的表达。方法]以松江鲈肌肉总RNA为模板,采用RT-PCR、5′-RACE和3′-RACE的方法扩增β-肌动蛋白基因cDNA片段,用RT-PCR方法检测组织表达。结果]获得了松江鲈β-肌动蛋白基因cDNA的3个片段,测序后拼接得到1905bp全长cDNA序列,其包含了1128个核苷酸的开放性阅读框,翻译编码375个氨基酸。核苷酸和氨基酸同源性分析发现,松江鲈β-肌动蛋白基因序列与点带石斑鱼、军曹鱼、红鲷鱼等同源性相对较高,与哺乳动物和鸟类同源性相对较低;系统发育分析表明,松江鲈β-肌动蛋白与点带石斑鱼关系最近。RT-PCR分析表明,该基因在检测的肌肉、肝脏、肠和脑4种组织均有表达。结论]首次得到了β-肌动蛋白基因cDNA全长序列,并证明了松江鲈的β-肌动蛋白基因非常保守。

Cloning and Sequence Analysis of Beta-actin Gene Full Length cDNA from Trachidermus fasciatus

Objective] The purpose of this experiment was to reveal the sequence and characteristics of Trachidermus fasciatus beta-actin gene.Method] Using total RNA of muscle in T.fasciatus as template,three cDNA fragments of beta-actin gene in T.fasciatus were amplified by RT-PCR,5＇-RACE and 3＇-RACE.Result] A full-length of 1905 bp beta-actin cDNA sequence in T.fasciatus,which includes a 1128 bp length open reading frame encoding a 375-amino acid peptide,was obtained.Sequence alignment of nucleotide and amino acid sequence revealed that T.fasciatus beta-actin shared high homology with that of Epinephelus coioides,Rachycentron canadum,Chrysophrys auratus and of relatively low homology with mammalian and bird.The phylogenetic analysis showed that T.fasciatus beta-actin had closest relationship with Epinephelus coioides.And RT-PCR analysis suggested that the beta-actin gene expressed in four tissues,i.e.,muscle,liver,intestine and brain.Conclusion] The full length sequence of beta-actin gene with high conservation in T.fasciatus was obtained for the first time.