对厦门和湛江海域的条纹斑竹鲨Chiloscyllium plagiosum(Bennett,1830)]的线粒体DNA控制区和细胞色素6(Cytb)基因进行PCR扩增和测序,获得线粒体DNA控制区、Cytb基因和tRNA^Pro。基因全序列(GenBank序列号:EU363740~EU363752)。结果表明,tRNA^Pro。基因长度为69bp,控制区长度为1094~1096bp,Cytb基因全序列长度为1146bp。tRNA^Pro。基因非常保守,未发现碱基变异。所测30个个体中,控制区只有4个多态位点,5种不同的单倍型;Cytb基因全序列共有10个多态性位点,7种单倍型。Cytb基因的1146个碱基编码381个氨基酸,氨基酸链共有3个变异位点,4种单倍型,厦门群体具有4种单倍型,湛江群体只有1种单倍型。综合Cytb基因和控制区序列,2个条纹斑竹鲨群体共有10种单倍型,其中厦门群体有9种单倍型,湛江群体仅4种单倍型。研究结果表明条纹斑竹鲨在控制区和Cytb基因序列上的遗传多样性均较低,厦门群体的遗传多样性水平高于湛江群体。
Genetic diversities of Chiloscylliurn plagiosum (Bennett, 1830) from Xiamen and Zhanjiang were investigated with mitochondrial control region and cytochrome b (Cyt b )gene sequence analysis. Control region and Cyt b gene fragments from 30 individuals were cloned with PCR method and sequenced. The sequences of the mitochondrial control region, Cyt b gene and tRNA^Pro gene were obtained. The complete sequences of the mitochondrial control region, Cyt b gene and tRNA^Pro gene were 69 bp,1 094-1 096 bp and 1 146 bp respectively, tRNA^Pro gene seemed conservative, without any polymorphism. Among 30 samples, there were 4 polymorphyism sites with 5 haplotypes for control region sequence and 10 polymorphyism sites with 7 haplotypes for Cyt b gene sequence. 1 146 bp nucleotide of Cyt b gene encoded 381 amino acids, and the amino acid chain had 3 polymorphyism sites with 4 haplotypes. Samples of Xiamen stock had 4 haplotypes while Zhanjiang stock only 1 haplotype. It was seemed that the genetic diversities in Cyt b and control region from C. plagiosurn in Xiamen were comparatively higher than those in Zhanjiang,though both appeared relatively low.