不同地域小稻蝗mtDNA部分序列及其相互关系

Mitochondrial DNA sequences and relationships of Oxya intricata individuals from different parts of China

测定了 9个不同地理区域的小稻蝗Oxyaintricata (St l)共 33个个体的线粒体DNA (mtDNA)细胞色素b基因部分序列 ,比较其同源性 ,计算核苷酸组成 ,并用瘤锥蝗科的曲尾似橄蝗Pseudomorphacrishollisi和斑腿蝗科的芋蝗Gesonulapuncti frons作外群构建NJ分子系统树。在获得的小稻蝗 432bp的序列中 ,A +T约占 70 3 % ,其中 30个核苷酸位点存在变异 (约占所测核苷酸的 6 9% ) ,有 5个位点引起了氨基酸的变异。就每个氨基酸密码子来看 ,第 3位点的A +T含量较高 ,达90 4%。由NJ树显示 ,小稻蝗mtDNA细胞色素b序列不同单倍型之间有一定的分歧 ,形成不同的簇类关系 ,其分枝与地理分布没有直接的对应关系 ,但总体上看 ,这种簇类关系基本上呈平行分布 ,没有明显的地域性差别。

Mitochondrial cytochrome b sequences (432 bp) were sequenced in 33 individuals of Oxya intricata from 9 different parts of China, homologous sequences compared, nucleotide composition calculated and the molecular phylogenetic tree was constructed with the Neighbor-Joining method using Gesonula punctifrons and Pseudomorphacris hollisi as outgroup species. In the sequences obtained, A%+T% was about 70 .3% and 30 nucleotide sites were substituted (about 6 .9%), among which only 5 substitutions resulted in the variation of amino acids. In the case of every amino acid code, A%+T% in the third site was much higher than the other two sites, reaching about 90 .4%. The NJ tree suggests that different individuals from the 9 areas in China were distributed in different clusters, but no clear relationships between haplotypes and geographic regions could be inferred. Since the branches of clusters are parallel, there is no evident difference between different areas.