大菱鲆免疫球蛋白轻链IgL全长cDNA的分离、鉴定及表达分析

实验采用末端快速扩增(RACE)技术从大菱鲆脾脏cDNA文库中筛选得到了免疫球蛋白轻链IgL的全长cD-NA片段。该序列包含47 bp的5′末端非编码区(5′UTR),738 bp的开放阅读框(ORF)和202 bp 3′UTR,整个开放阅读框编码246个氨基酸。系统发生分析表明大菱鲆IgL基因与五条鰤的IgL基因起源关系最近。RT-PCR分析表明,大菱鲆IgL基因只在正常脾脏、肾脏和头肾组织中表达;IgL在大菱鲆胚胎发育细胞期就已开始表达,在大菱鲆胚胎尾芽期和体节期表达持续增强;在鳗弧菌感染大菱鲆脾脏和头肾早期均检测到IgL基因强烈表达,后期表达逐渐减弱;大菱鲆胚胎细胞(TEC)在用鳗弧菌感染48h后,IgL开始表达。这些结果均表明IgL基因在大菱鲆免疫应答中起着重要作用。

Cloning, Characterization and Expression Analysis of an Immunoglobulin Light Chain Gene from Turbot(Scophthalmus maximus)

A novel turbot (Scophthalmus maximus) immunoglobulin light chain (IgL) was screened from a turbot spleen cDNA library. The complete cDNA of the turbot IgL contains a 47 bp 5' UTR, a 738 bp open reading frame (ORF) encoding 246 amino acids and a 202 bp 3'UTR. Phylogenetic analysis showed that the turbot IgL clustered with S.quinqueradiata IgL. RT-PCR demonstrated that turbot IgL was expressed in spleen, kidney and head kidney from uninfected adults. IgL expressed during the early stages of embryo development and gradually increased until larva stage. The expression of IgL was also dramatically increased after challenge in turbot spleen and head kidney after 5 h. Furthermore, the turbot LCK was induced after 48 h in turbot embryonic cells (TECs) after challenge with Vibrio anguillarum. These results indicated that the turbot LCK played an important role in turbot immune response.