中华假磷虾线粒体DNA COI基因片段序列分析

Analysis of Mitochondrial DNA CO I Gene Fragment of Pseudeuphausia sinica

采用苯酚-氯仿提取、异丙醇沉淀提取中华假磷虾基因组DNA;以相应引物经PCR扩增得到线粒体DNACOI片段;PCR产物采用化学法与载体(pGEM-TEasyVector)重组基因、热休克法转化重组质粒至感受态大肠杆菌(JM109)、氨苄LB培养基扩大培养;测序.结果表明,中华假磷虾线粒体COI碱基709bp,其碱基组成A、T、G、C含量分别为28 59%、35 35%、17 61%和18 45%(国际基因库索引号AY754819);与同科内其它3属10种磷虾的mtCOI基因片段核苷酸组成相似.

Pseudeuphausia sinica (Euphausiacea, Crustacea) is abundant in the coastal and neritic waters of the East China Sea and the Southern Yellow Sea all the year round, and is the important food for many fishes, especially for fish larvae. The genomic DNA of Pseudeupharsia sinica, collected from Xiamen waters in May of 2002, was obtained by phenol: Chloroform:isoamyl alcohol (25:24:1) extraction and isopropyl alcohol precipitation. Mitochondrial DNA COI gene was successfully amplified and sequenced. 709 base pairs of mtCOI were obtained under our PCR conditions. The composition of A, T, G and C is 28.59%, 35.35% 17.61% and 18.45%, respectively, which are similar to the nucleotide composition of other ten species that belong to three genera in the same family Euphausiidae. Three seecimen met in the study have four mutable sites including transversion mutation and transition mutation. Not only organism themselves but also environmental factors which might lead to the mutation are discussed in the paper.