头足纲线粒体基因组结构分析  

Analysis of Mitochondrial Genome Characteristics in Cephalopoda

作　　者：赵娜娜[1,2] 孟学平[2] 申欣[2] 程汉良[2] 阎斌伦[2] 郑立波[2] 朱笑琳 刘兆普[1] 

机构地区：[1]南京农业大学资源与环境科学学院,江苏海洋生物重点实验室,江苏南京210095 [2]淮海工学院海洋学院,江苏海洋生物技术重点实验室,江苏连云港222005

出　　处：《水产科学》2013年第3期146-152,共7页Fisheries Science

基　　金：江苏省海洋生物技术重点实验室开放课题(2011HS009,2009HS13);江苏省自然科学基金资助项目(BK2007066,BK2008191);江苏省海洋资源开发研究院科技开放基金资助项目(JSIMR11B19);中央财政支持地方高校发展专项资金资助项目(CXTDD1,CXTD04)

摘　　要：用生物信息学方法,利用GenBank线粒体基因组全序列信息,对头足纲15个物种基因组结构进行了分析,结果显示头足纲线粒体基因组长度为15 617～20 306bp,基因组编码链的A+T含量为59.58%～78.12%,表现出不同程度的AT偏好性;15个物种的线粒体基因组PCGs相对保守,有2个共同的基因块,可作为头足类的线粒体基因组标志;萤乌贼、鸢乌贼、茎柔鱼、太平洋褶柔鱼、大王乌贼PCGs cox1、cox2、cox3、atp6、atp8为双拷贝,且重复基因的变异很小,这是头足纲物种不同于其他物种的显著特征;多数PCGs以ATG为起始密码,以TAA为终止密码,在cox2、cob、nad2-nad6中存在不完全终止密码;在13个PCGs中,nad2和nad4L的差异最大,atp8和cox1最保守;15个种类的遗传距离为0.033～0.561,大脐鹦鹉贝与其他种类的遗传距离最大(0.529～0.561);基于线粒体基因组编码蛋白质氨基酸序列的系统发育分析结果与形态学分类结果一致。The basic characteristics of 15 cephalopoda mitochondrial genomes were analysed. Results showed that the lengths of cephalopoda mitochondrial genomes were varied between 15 617 bp and 20 306 bp; the A＋T content（from 59.58% to 78.12 %）was higher than C＋G content; the protein coding genes cox1, cox2, cox3, atp6 and atp8 have double copy in Watasenia scintillans, Sthenoteuthis oualaniensis, Dosidicus gigas, Todarodes pacificus and Architeuthis dux, the duplicate gene＇s variation is small, the others are 37 genes; furthermore, most of protein coding genes started with ATG, terminated with TAA, some PCGs of cox2, cob, nad2-nad6 terminated with T- or TA-. The greater nucleotide change in had2 and nad4L is found in 13 PCGs and the sequence of atp8 and cox1 is more conservative than others. The results of sequence differentiation analysis indicated that the genetic distance is between 0. 033 and 0. 561 in the 15 species, and is between 0. 529 and 0.561 in Nautilus macromphalusa and others; while the Octopus has the largest genetic distance （0.561） ; the results of phylogeny analysis based on the PCGs are according with the results of morphology.

关 键 词：头足纲 线粒体基因组 基因特征 遗传差异 

分 类 号：Q786[生物学—分子生物学]