利什曼原虫中国分离株SSUrDNA多变区序列分析

目的分析我国荒漠、山丘疫区利什曼原虫分离株的SSUrDNA多变区序列差异。方法nDNA进行PCR扩增,将扩增出的SSUrDNA基因的特异片段克隆于pGEMR-TEasyVector上,采用通用引物M13进行PCR扩增,全自动测序仪测序。结果序列分析显示本文报道的荒漠、山丘疫区的2株利什曼原虫（L.d.XJ771、L.d.SC6）的SSUrDNA序列大小均为392bp;序列差异发生在两个独特序列区（UQ-Ⅰ和UQ-Ⅱ）,无移码突变;与GeneBank中的利什曼原虫比较分析,同源性在98%以上。结论我国荒漠、山丘疫区利什曼原虫分离株之间的SSUrDNA多变区的碱基序列有差异;荒漠疫区分离株L.d.XJ771与国际标准株L.d.DD8的SSUrDNA多变区的碱基序列完全相同。

SEQUENCE ANALYSIS OF SSUrDNA VARIABLE REGION OF DIFFERENT LEISHMANIA ISOLATES OF CHINA

Aim　 To analyze the sequence of the SSU rDNA variable region of Leishmania isolates from desert and hill foci of China. Methods　 Specific SSU rDNA fragments from nuclear DNA of two Leishmania isolates were amplified by PCR and then cloned into pGEMR-T Easy Vector.After that, the specific fragments were sequenced by the automated DNA sequencer. Results　Sequence analysis showed that the amplified DNA fragments of two Leishmania isolates(L.d.XJ771 and L.d.SC6) were all 392bp in length, point mutations were located in the two unique sequence (UQ-Ⅰ and UQ-Ⅱ),and no insertion/deletion found. The identities of comparison of Leishmania in GeneBank were more than 98%.Conclusion　Sequence difference of the SSU rDNA variable region existed among Leishmania isolates from desert and hill foci; The sequences of the SSU rDNA variable region of L.d.XJ771 isolate and L. d.DD8 were identical.