两种鼠蛲虫线粒体cytb基因的种间及种内序列变异研究

摘要

首次研究了小鼠四翼无刺线虫和隐管状线虫在线粒体细胞色素b(cytb)基因部分序列的种间及种内变异. 从甘肃兰州地区LY和LS两个实验动物中心的小鼠肠道内收集了41个蛲虫样品(LY1-20、LS1-21), PCR扩增其cytb基因部分序列, 经测序和序列分析结果发现：四翼无刺线虫cytb有效序列为531bp, 而隐管状线虫有效序列为567bp. 用软件ClustalX1. 83截取两种鼠蛲虫cytb基因长度共同的序列, 比对后发现无种内差异, 但种间差异高达31. 51%. 研究结果初步表明, cytb基因序列在鼠蛲虫种内较保守, 但种间存在较高的变异率, 可作为两种常见鼠蛲虫种间分子鉴定的遗传标记.%The obj ective of this study was to elucidate sequence variation in mitochondrial cytochrome b (cytb)gene between and within Aspiculuris tetraptera and Syphacia obvelate collected from mice in Lanzhou,China.41 pinworm samples were collected from mice in two laboratory animal centers in Lanzhou,Gansu province,and their partial cytb sequences were amplified by PCR.Sequence analysis re-vealed that the cytb sequences of A.tetraptera and S.obvelate were 5 6 7 bp and 5 3 1 bp,respectively.While no sequence variation in the cytb sequences was detected within each of the two pinworms,the inter-specific sequence difference was 3 1 .5 1% between the common A.tetraptera and S.obvelate.These findings demon-strated that cytb sequences were quite conserved within mouse pinworms,but significantly differed between different pinworm species,indicating that cytb sequences can be used as genetic marker for the differentia-tion of different pinworms.These results have implications for further population genetics study of pin-worms.