Park J-K, Kim K-H, Kang S, Jeon H K, Kim J-H, Littlewood D T J, Eom K S
Department of Parasitology, College of Medicine, Chungbuk National University Cheongju, Chungbuk 361-763, Republic of Korea.
Parasitology. 2007 May;134(Pt 5):749-59. doi: 10.1017/S003118200600206X. Epub 2007 Jan 11.
The complete nucleotide sequence of the mitochondrial genome was determined for the fish tapeworm Diphyllobothrium latum. This genome is 13,608 bp in length and encodes 12 protein-coding genes (but lacks the atp8), 22 transfer RNA (tRNA) and 2 ribosomal RNA (rRNA) genes, corresponding to the gene complement found thus far in other flatworm mitochondrial (mt) DNAs. The gene arrangement of this pseudophyllidean cestode is the same as the 6 cyclophyllidean cestodes characterized to date, with only minor variation in structure among these other genomes; the relative position of trnS2 and trnL1 is switched in Hymenolepis diminuta. Phylogenetic analyses of the concatenated amino acid sequences for 12 protein-coding genes of all complete cestode mtDNAs confirmed taxonomic and previous phylogenetic assessments, with D. latum being a sister taxon to the cyclophyllideans. High nodal support and phylogenetic congruence between different methods suggest that mt genomes may be of utility in resolving ordinal relationships within the cestodes. All species of Diphyllobothrium infect fish-eating vertebrates, and D. latum commonly infects humans through the ingestion of raw, poorly cooked or pickled fish. The complete mitochondrial genome provides a wealth of genetic markers which could be useful for identifying different life-cycle stages and for investigating their population genetics, ecology and epidemiology.
已确定了阔节裂头绦虫线粒体基因组的完整核苷酸序列。该基因组长度为13,608碱基对，编码12个蛋白质编码基因（但缺少atp8）、22个转运RNA（tRNA）和2个核糖体RNA（rRNA）基因，这与迄今为止在其他扁虫线粒体（mt）DNA中发现的基因组成相对应。这种假叶目绦虫的基因排列与迄今已鉴定的6种圆叶目绦虫相同，只是在这些其他基因组之间结构上只有微小差异；微小膜壳绦虫中trnS2和trnL1的相对位置发生了互换。对所有完整绦虫mtDNA的12个蛋白质编码基因的串联氨基酸序列进行的系统发育分析证实了分类学和先前的系统发育评估，阔节裂头绦虫是圆叶目绦虫的姐妹分类单元。不同方法之间的高节点支持和系统发育一致性表明，线粒体基因组可能有助于解决绦虫目内的亲缘关系。所有裂头绦虫物种都感染食鱼脊椎动物，阔节裂头绦虫通常通过摄入生的、未煮熟或腌制的鱼感染人类。完整的线粒体基因组提供了大量的遗传标记，可用于识别不同的生命周期阶段以及研究它们的群体遗传学、生态学和流行病学。
