10株巨型艾美球虫rDNA-ITS-1部分序列测定与分析

Partial sequence analysis of ITS-1 rDNA of ten Eimeria maxima strains

用一对种特异性引物,对国内10株巨型艾美球虫ITS-1区进行PCR扩增,对扩增产物纯化、测序与分析,并用DNAStar软件对所检测的10株巨型艾美球虫与GenBank中的所有巨型艾美球虫的ITS-1相应序列进行系统发生进化关系分析。结果显示,扬州株、龙岩株和福州株的ITS-1部分序列片段长度为152bp,其余各株均为151bp。10株巨型艾美球虫的同源性为90.7%～100%,在构建的系统发生进化树中分成2大系群,凤阳株形成一个单系群,其余9株为另一系群。虫株间的亲缘关系与地理位置不尽一致,与免疫交叉保护力无相关性。

The partial sequence of the ITS-1 regions from the ten E.maxima strains isolated in China were amplified by PCR with a pair of species-specific primers and sequenced. Phylogenetic relations were analyzed among ten E.maxima strains and the reference strains in GenBank by using DNAStar software. The results showed that the partial ITS-1 sequences of Yangzhou strain, Longyan strain and Fuzhou strain were 152 bp in length, while all other strains were 151 bp. The sequence similarities of the ten strains ranged between 90.7 %-100 %. Phylogenetic tree showed that ten E.maxima strains could be divided into two major groups, in which Fengyang strain formed one clade, and other strains and the reference strains clustered together to form another clade. The similarities among the ten strains were not related to geographical distribution, and the phylogenetic relationships showed no correlation with the known immunological cross-reactivates of these strains.