Ouakad Meriem, Chenik Mehdi, Ben Achour-Chenik Yosser, Louzir Hechmi, Dellagi Koussay
Laboratoire d'Immunopathologie, Vaccinologie et Génétique Moléculaire, Institut Pasteur de Tunis, 13, Place Pasteur 1002, Tunis-Belvédère, Tunisia.
Parasitol Res. 2007 Jan;100(2):255-64. doi: 10.1007/s00436-006-0277-x. Epub 2006 Oct 3.
Trying to identify virulence genes of wild Leishmania (L.) major parasites, the species responsible for zoonotic cutaneous leishmaniasis, we compared, using differential display technique, gene expression in two L. major isolates obtained from human lesions and characterized by their contrasting pathogenicity in the BALB/c mouse model. The analysis was performed on amastigotes derived from BALB/c mice lesions. A total of 13 different clones were identified, but the use of reverse transcription and real-time polymerase chain reaction technique did not allow us to confirm any of these clones as differentially expressed. However, the fact that we used the amastigote stage of the parasite led us the identification of amastigote-specific genes, essentially (8 among 13). They are overexpressed, two to seven times, in amastigotes relative to promastigotes. Sequence analysis revealed that two of them namely LPG3 and the ATP dependent RNA helicase correspond to previously described amastigote-specific genes. The others correspond to genes involved in important biological process. Their better characterization could help the development of new drugs targeting the processes in which these molecules are involved.
为了鉴定引起人兽共患皮肤利什曼病的野生硕大利什曼原虫（Leishmania (L.) major）寄生虫的毒力基因，我们使用差异显示技术比较了从人类病变中分离得到的、在BALB/c小鼠模型中具有不同致病性的两种硕大利什曼原虫分离株的基因表达情况。分析是在源自BALB/c小鼠病变的无鞭毛体上进行的。共鉴定出13个不同的克隆，但使用逆转录和实时聚合酶链反应技术无法确认这些克隆中有任何一个存在差异表达。然而，我们使用寄生虫无鞭毛体阶段这一事实使我们鉴定出了无鞭毛体特异性基因，基本上（13个中有8个）。相对于前鞭毛体，它们在无鞭毛体中的表达量高出两到七倍。序列分析表明，其中两个基因，即LPG3和ATP依赖性RNA解旋酶，与先前描述的无鞭毛体特异性基因相对应。其他基因对应于参与重要生物学过程的基因。对它们进行更深入的表征可能有助于开发针对这些分子所参与过程的新药。
