鳡线粒体ND5基因测序与序列特征分析

Molecular Cloning and Sequence Analyses of Elopichthys bambusa Mitochondrial NADH Dehydrogenase Subunit 5(ND5) Gene

通过PCR扩增并克隆测序,获得了鳡(Elopichthys bambusa)线粒体ND5基因序列,该基因全长为1836bp,编码611个氨基酸残基的蛋白质,其起始密码子为ATG,终止密码子为TAA.分析该基因碱基组成及密码子使用情况,发现A+T含量高于G+C,并且在密码子第三位点存在明显的反G偏倚.将鳡ND5基因序列与GenBank中其他10个物种的ND5基因序列进行比对,结果表明鳡与鲢鱼的亲缘关系最近,青鱼次之.用NJ法构建11个物种的系统进化树,结果表明雅罗鱼亚科、鲌亚科和鲢亚科之间的亲缘关系很近,而鲤亚科与它们之间的亲缘关系相对较远.

The mitochondrial NADH dehydrogenase subunit 5（ND5） gene sequence of Elopichthys bambusa was determined by using PCR and sequencing.Analyses of the E.bambusa mitochondrial ND5 gene showed that the length of the ND5 gene was 1836bp,which encoded 611 amino acid long protein,while the start codon and stop codon of the gene were ATG and TAA,respectively.The base compositions of the ND5 gene showed that A ＋ T content was higher than G＋C content and there was an apparent bias against G at the third codon positions.Sequence alignment of ND5 genes among E.bambusa and other 10 species in GenBank showed that E.bambusa had the closest genetic relationship with Hypophthalmichthys molitrix,and took the second place with Mylopharyngodon piceus.A phylogenetic tree of these 11 species constructed by using the neighbor-joining method indicated that the relationship between Leuciscinae,Culterinae and Hypophthalmichthyinae was close,while the relationship between Cyprininae with these three subfamilies was relatively far.