中文摘要：

与单基因相比,线粒体基因组是一个完整的体系,具有信息量丰富等优点,在过去的十几年间被广泛地应用于后生动物关键类群的分子系统发育和群体遗传学的研究.本论文综合分析了海星纲7个物种（多棘海盘车、赭色豆海星、多棘槭海星、砂海星、长棘海星、棘冠海星和海燕）线粒体基因组全序列,全面揭示了海星纲线粒体基因组的基本特征.海星线粒体基因组均编码后生动物线粒体基因组标准的37个基因.7个海星线粒体基因组的基因排列完全一致;与海胆纲及海参纲楯手目线粒体基因组的基因排列相比,海星线粒体基因组的基因排列存在4.6 kb长片段的倒位.长棘海星属13个线粒体蛋白质编码基因的非同义替换率（Ka）与同义替换率（Ks）比值都低于1.000 0（为0.006 0～0.221 9）,显示出较强的负（纯化）选择.对海星纲线粒体基因组的基因变异位点分析结果表明,nad5、nad4基因可作为备选的分子标记,应用于海星纲群体遗传学的研究中.同时,在长棘海星属线粒体基因组变异位点分析中,nad5、nad4基因仍然可作为备选的分子标记,用于分析长棘海星不同群体及物种之间的生物多样性,为合理利用其生物资源及其生物多样性的保护提供基础资料.

英文摘要：

Over the past decades,inference of phylogenetic relationship and population diversity of metazoan species based on mitochondrial genome sequences has become popular.This resulted from many advantages offered by mitochondrial genomes over single gene.The basic characteristics of starfish mitochondrial genomes are fully revealed by comprehensive analysis of 7 starfish（Asterias amurensis,Pisaster ochraceus,Astropecten polyacanthus,Luidia quinaria,Acanthaster planci,Acanthaster brevispinus and Asterina pectinifera） mitochondrial genome sequences.Starfish mitochondrial genomes contain 37 standard metazoan genes.The gene order of 7 starfish mitochondrial genomes is identical,and also exists the inversion of 4.6 kb fragment compared with sea urchins and sea cucumbers（Holothuroidea： Aspidochirotida） mitochondrial genomes.The Ka/Ks ratio in all 13 mitochondrial protein genes of Acanthaster is lower than 1（0.006 0～0.221 9）,indicating a strong negative（purification） selection.From the genetic variation loci analysis of major coding genes in starfish mitochondrial genomes,nad5 and nad4 genes can be used as alternative molecular markers,to analyze biodiversity among different species and populations of starfish.Meanwhile,from the genetic variation loci analysis of Acanthaster,nad5 and nad4 genes also can be used as alternative molecular markers,to analyze the diversity among different populations and species of Acanthaster.Those molecular markers can provide a basic information for the use of the biological resources rationally and conservation of starfish diversity.