摘要
目的分析河南省2015年输入性卵形疟原虫富色氨酸抗原(Plasmodium ovale tryptophan-rich antigen,Po TRA)基因序列。方法采集河南省2015年22例输入性卵形疟患者的血样,收集患者相关信息。提取血样DNA,用巢式PCR方法扩增Po TRA基因,连接至p MD18-T载体,提取质粒进行测序,在Gen Bank中进行同源性比对,判断卵形疟原虫的亚种,并对其基因长度及种类进行分析。对Po TRA基因的氨基酸序列进行比对,分析氨基酸的差异。用邻接法构建系统进化树,分析样本间的亲缘关系。结果 22例卵形疟中,8例为卵形疟原虫wallikeri亚种(P.ovale wallikeri),占36.4%,Po TRA基因长度有245和299 bp 2种类型,以245 bp为主;14例为卵形疟原虫curtisi亚种(P.ovale curtisi),占63.6%,Po TRA基因长度有299、317和335 bp等3种类型,以299 bp为主。氨基酸序列比对显示,wallikeri亚种的2种基因类型相差2个氨基酸单元(MANPINMANPIN和AITPIN),curtisi亚种的3种基因类型间相差2个氨基酸单元(TITPIS和TINPIN)。系统进化树显示,22例样本分为curtisi和wallikeri 2个亚群,其中curtisi亚群又分为2个亚支,299 bp的样本在同一亚支内,317和335 bp的样本在另一亚支内,亲缘关系更近。结论 2015年河南省输入性卵形疟有curtisi和wallikeri 2个亚种,其Po TRA基因存在多态性,curtisi亚种有3种基因类型,wallikeri亚种有2种基因类型。
Objective To analyze the genetic sequence of tryptophan-rich antigen (PoTRA) gene of Plasmodium ovale subspecies from imported malaria cases in Henan Province in 2015. Methods Blood samples were collected from 22 imported ovale malaria cases in Henan Province in 2015. After DNA extraction, PoTRA was amplified by nested PCR, and was inserted into the pMD18-T vector. The plasmid was extracted and sequenced, and the results were blasted in GenBank to determine the subspecies of P. ovale. The sizes and species of the PoTRA gene were analyzed. The amino-acid sequence of PoTRA was also aligned to analyze the difference in amino acid sequence. The phylogenetic tree was constructed to analyze the genetic relationship among the samples by neighbor-joining. Results Of the 22 imported cases, eight (36.4%) were infected with P. ovale wallikeri, which had two sizes, the predominant 245 and 299 bp. The other 14 cases (63.6%) were infected with P. ovale curtisi, which had three sizes, the predominant 299, 317 and 335 bp. Amino-acid sequence alignment revealed that the two types of P. ovale wallikeri differed in two amino-acid units, MANPINMANPIN and AITPIN, while the three types of P. ovale curtisi differed in amino-acid units TITPIS and TINPIN. The phylogenetic tree showed that the 22 samples belonged to two subpopulations of P. ovale curtisi and P. ovale wallikeri, wherein the P. ovale curtisi was further divided into two sub-branches, and samples with sizes of 317 and 335 bp were in the same sub-branch with a closer genetic relationship. Conclusion Two subspecies, P. ovale curtisi and P. ovale wallikeri, are identified from the imported ovale malaria cases in Henan Province in 2015. The P. ovale curtisi has three genetic types and P. ovale wallikeri has two genetic types of PoTRA gene, revealing genetic polymorphisms of PoTRA.
出处
《中国寄生虫学与寄生虫病杂志》
CAS
CSCD
北大核心
2017年第1期13-17,共5页
Chinese Journal of Parasitology and Parasitic Diseases
基金
河南省医学科技攻关计划项目(No.201304053
201602318)~~