Identification of a disulfide isomerase protein of Leishmania major as a putative virulence factor
Identification of a disulfide isomerase protein of Leishmania major as a putative virulence factor
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DOI：
10.1128/iai.70.7.3576-3585.2002
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发表时间：
2002-07-01
影响因子：
3.1
通讯作者：
Dellagi, K
中科院分区：
文献类型：
--
作者：
Ben Achour, Y;Chenik, M;Dellagi, K
先前已经使用了几种方法来阐明利什曼原虫毒力的遗传基础。一般来说，它们是基于实验室利什曼原虫克隆的遗传修饰或生长在选择剂的存在下。在先前的研究中，我们证明了从人类皮肤病变新鲜分离的主要利什曼原虫在BALB/c小鼠中诱导的实验疾病的严重程度上显示出显着差异。在这里，我们使用mRNA差异显示技术，分析基因表达的L。主要的前鞭毛体表现出不同程度的毒性。我们已经确定了一种新的利什曼原虫基因编码的477个氨基酸的蛋白质，表现出两个不同的区域，是相同的推定的活性位点序列（CGHC）的真核蛋白质二硫键异构酶（PDI）。重组蛋白显示出特异的PDI酶活性。这个L。主要二硫键异构酶蛋白（LmPDI）在高毒性菌株中主要在mRNA和蛋白质水平上表达。特异性PDI抑制剂消除了重组蛋白的酶活性，并深刻影响寄生虫的生长。这些发现表明LmPDI可能在利什曼原虫的自然致病性中起重要作用，并可能构成抗利什曼原虫化疗的新靶点。
Several approaches have been previously used to elucidate the genetic basis of Leishmania virulence. In general, they were based on laboratory Leishmania clones genetically modified or grown in the presence of selecting agents. In a previous study, we demonstrated that Leishinania major freshly isolated from human cutaneous lesions showed significant differences in the severity of the experimental disease induced in BALB/c mice. Here, using the mRNA differential display technique, we analyzed gene expression in L. major promastigotes showing different levels of virulence. We have identified a novel Leishmania gene encoding a 477-amino-acid protein exhibiting two distinct regions that are identical to the putative active-site sequence (CGHC) of the eukaryotic protein disulfide isomerase (PDI). The recombinant protein displayed a specific PDI enzymatic;activity. This L. major disulfide isomerase protein (LmPDI) is predominantly, expressed, at both the mRNA and protein levels, in highly virulent strains. Specific PDI inhibitors abolished the enzymatic activity of the recombinant protein and profoundly affected parasite growth. These findings suggest that LmPDI may play an important role in Leishmania natural pathogenicity and may constitute a new target for anti-Leishmania chemotherapy.