Alcolea Pedro J, Alonso Ana, García-Tabares Francisco, Toraño Alfredo, Larraga Vicente
Department of Molecular Microbiology and Biology of Infections and Service of Proteomics and Genomics, Centro de Investigaciones Biológicas (Consejo Superior de Investigaciones Científicas), Madrid, Spain.
Servicio de Inmunología, Centro Nacional de Microbiología, Virología e Inmunología Sanitarias (Instituto de Salud Carlos III), Majadahonda, Madrid, Spain.
PLoS One. 2014 Dec 11;9(12):e113837. doi: 10.1371/journal.pone.0113837. eCollection 2014.
The life cycle of the trypanosomatid Crithidia fasciculata is monogenetic, as the unique hosts of these parasites are different species of culicids. The comparison of these non-pathogenic microorganisms evolutionary close to other species of trypanosomatids that develop digenetic life cycles and cause chronic severe sickness to millions of people worldwide is of outstanding interest. A ground-breaking analysis of differential protein abundance in Crithidia fasciculata is reported herein. The comparison of the outcome with previous gene expression profiling studies developed in the related human pathogens of the genus Leishmania has revealed substantial differences between the motile stages of these closely related organisms in abundance of proteins involved in catabolism, redox homeostasis, intracellular signalling, and gene expression regulation. As L. major and L. infantum agglutinate with peanut lectin and non-agglutinating parasites are more infective, the agglutination properties were evaluated in C. fasciculata. The result is that choanomastigotes are able to agglutinate with peanut lectin and a non-agglutinating subpopulation can be also isolated. As a difference with L. infantum, the non-agglutinating subpopulation over-expresses the whole machinery for maintenance of redox homeostasis and the translation factors eIF5a, EF1α and EF2, what suggests a relationship between the lack of agglutination and a differentiation process.
锥虫目寄生虫纤细短膜虫的生命周期是单源的，因为这些寄生虫的唯一宿主是不同种类的库蚊。将这些非致病性微生物与其他具有双源生命周期并给全球数百万人带来慢性严重疾病的锥虫目寄生虫物种进行进化比较，具有极大的研究价值。本文报道了对纤细短膜虫中差异蛋白质丰度的开创性分析。将结果与之前在利什曼原虫属相关人类病原体中开展的基因表达谱研究进行比较后发现，这些密切相关生物体的活动阶段在参与分解代谢、氧化还原稳态、细胞内信号传导和基因表达调控的蛋白质丰度方面存在显著差异。由于硕大利什曼原虫和婴儿利什曼原虫会与花生凝集素发生凝集反应，且不发生凝集反应的寄生虫更具感染性，因此对纤细短膜虫的凝集特性进行了评估。结果是，漏斗鞭毛体能够与花生凝集素发生凝集反应，并且还可以分离出一个不发生凝集反应的亚群。与婴儿利什曼原虫不同的是，不发生凝集反应的亚群过度表达了维持氧化还原稳态的整个机制以及翻译因子eIF5a、EF1α和EF2，这表明不发生凝集反应与分化过程之间存在关联。
