牙鲆、石鲽和川鲽的线粒体16S rRNA基因片段的序列比较研究

Comparative Study of Mitochondrial 16S rRNA Gene Fragments Among Para lichthys olivaceus Kareius bicoloratus and Platichthys flesus

以相应引物对牙鲆 (Paralichthys olivaceus )和石鲽 (K .areius bicoloratus)的线粒体 16 Sr RNA基因片段进行了 PCR扩增 ,PCR产物经 T载体连接之后进行了克隆、测序 ,均得到了5 90 bp的碱基序列 ,并将其与 Gen Bank中牙鲆线粒体全序列相应片段和川鲽 (Platichthys flesus)相应片段进行比较 ,结果表明 ,川鲽和石鲽序列差异很小 (核苷酸差异数为 7,同源性为 98.8% ) ;而牙鲆与川鲽和石鲽的序列差异明显 (核苷酸差异数为 90～ 93,同源性约为 84 % ) ,且大多数核苷酸变异位点集中在序列中部大约 2 0 0

Mitochondrial 16S rRNA gene fragments of flatfish Paralichthys olivaceus and Kareius bicoloratus were amplified via PCR, a nd the PCR products were ligated into T-vector, cloned and sequenced. 590bp nucl eotide sequences were retrieved for both species. The two sequences were aligned and compared with corresponding fragment of Platichthys.flesus and that of P.olivaceus mitochondrial complete genome. It's indicated that there is rela tively little sequence differences between P. flesuus and K. bicoloratus (homology 98.8%), but significant sequence differences exist between P.olivac eus and P. flesus, K. bicoloratus (homology around 84%), with most variabl e 200bp region in the middle. The sequences could be used for phylogenetic resea rch in flatfish species.