Objective:To analyse the rar gene repertoire and characterise the rhondroitin sulphate A (CSA)-binding activity of the Duffy-binding like(I)BI.) domains encoded by the var2csa gene of a Plasmodium falciparum(P.falciparum) isolate in Hainan Province,China.Methods:The sequences of var DBL1 regions were PCR-amplified,sequenced and the sequence characteristics was bioinformalically analysed.Recombinant proteins encoded by the var2csa genes were expressed and purified.The binding activities of the recombinant proteins to CSA receptor was detected by ELISA assays.Results:Fifty six unique DBI.a sequences were obtained,and the sequences represented similar diversity to the var genes of the genome parasite 3D7.There are two var2csa genes in the P.falciparum isolated from Hainan Province.Unlike in other falciparum parasites such as HB3,the two var2csa genes are more diverged.The receptor-binding capacity of DBL-5εand DBI.-6 e domains of HN var2CSA was studied.Conclusions:This work represented the diversity of rar genes of a P.falciparum isolate in China.
Ning JiangLi MengHui-Jun LuWei KangShuai PengWei-Qing PanJi-Gang YinQi-Jun Chen
目的日本血吸虫虫卵中可能参与免疫调节的分子的克隆及其多态性分析。方法在NCBI数据库及国家人类基因组南方研究中心(Chinese National Human Genome Center,CHGC)日本血吸虫基因数据库中筛选出两个类IPSE(IL-4-inducing principle of S.mansoni eggs)基因(AY812212和AY223149)、一个类蛇毒过敏样蛋白基因(AY812797)和一个类亲环素蛋白基因(AY814078)。用RT-PCR检测表达谱,并从日本血吸虫虫卵cDNA文库中克隆这四个基因。定向克隆入质粒pET28-a,经双酶切鉴定筛选得重组的阳性克隆后测序。所得序列应用生物信息学分析软件Vector NTI Suite 7.0、Mega 4.0和在线软件Rankpep进行初步分析。结果成功构建了4个重组质粒pET28a-223149,pET28a-812212,pET28a-812797和pET28a-814078,并测定和分析了这4个基因。结论日本血吸虫虫卵基因存在基因多态性,可能与免疫逃避有关。
