鲈鱼ZnT基因的cDNA克隆及生物信息学分析

Cloning and bioimformatics analysis of cDNA ZnT in Lateolabrax japonicus

锌转运蛋白(zinc transporters,Zn T)在细胞锌的储藏,释放和分布中起了重要的作用。运用RT-PCR和SMART RACE方法从鲈鱼肝脏克隆得到了鲈鱼Zn T基因全长c DNA序列。结果显示,鲈鱼Zn T全长为1747 bp,包括5'非翻译区84 bp,3'非翻译区490 bp,开放阅读框1173 bp,可编码390个氨基酸。生物信息学分析表明该蛋白有6次跨膜结构,N端和C端均位于细胞膜内侧,第IV和第V跨膜区之间的环富含组氨酸。鲈鱼Zn T的氨基酸序列与其他生物的Zn T7序列有高度的相似性:斑马鱼,85.6%;大西洋鲑,85.4%;红鳍东方鲀,84.3%;人,75.1%;小鼠,73.8%。聚类分析显示鲈鱼Zn T首先与其它鱼类和人Zn T7成一簇,再与鱼的其他类别Zn T聚合,说明分离到的鲈鱼Zn T为Zn T7。

Zinc transporters family plays important roles in cellular zinc storage,release and distribution. This study described the cloning and sequence analysis of the zinc transporters（ Zn T） in the seabass（ Lateolabrax japonicus） using RT-PCR and SMART RACE.The acquired Zn T was 1747 bp in length,including a 84 bp 5＇-UTR,a 490 bp 3＇-UTR and a 1173 bp coding sequence which could code 390 amino acid. The obtained sequence was postulated to have six transmenbrane domains,an intracellular N-terminus and C-terminus and a His-rich loop between transmembrane domains IV and V. The sequence alignment analysis indicated that the obtained amino acid sequence of Zn T shared high identity with Zn T7 s of other species： Danio rerio,85. 6%; Salmo salar,85. 4%; Takifugu rubripes,84. 3%; Homo sapiens,75. 1%; Mus musculus 73. 8%. Phylogenetic analysis indicated that the acquired Zn T was first clustered with Zn T7 of teleost and human,then clusterd with other type Zn T of teleost,which showed that the obtained Zn T was type Zn T7.