Wiedmer Stefanie, Erdbeer Alexander, Volke Beate, Randel Stephanie, Kapplusch Franz, Hanig Sacha, Kurth Michael
Institute for Zoology, Technische Universität Dresden, Helmholtzstraße 10, 01062 Dresden, Germany.
Parasite. 2017;24:50. doi: 10.1051/parasite/2017049. Epub 2017 Dec 6.
The genus Eimeria (Apicomplexa, Coccidia) provides a wide range of different species with different hosts to study common and variable features within the genus and its species. A common characteristic of all known Eimeria species is the oocyst, the infectious stage where its life cycle starts and ends. In our study, we utilized Eimeria nieschulzi as a model organism. This rat-specific parasite has complex oocyst morphology and can be transfected and even cultivated in vitro up to the oocyst stage. We wanted to elucidate how the known oocyst wall-forming proteins are preserved in this rodent Eimeria species compared to other Eimeria. In newly obtained genomics data, we were able to identify different gametocyte genes that are orthologous to already known gam genes involved in the oocyst wall formation of avian Eimeria species. These genes appeared putatively as single exon genes, but cDNA analysis showed alternative splicing events in the transcripts. The analysis of the translated sequence revealed different conserved motifs but also dissimilar regions in GAM proteins, as well as polymorphic regions. The occurrence of an underrepresented gam56 gene version suggests the existence of a second distinct E. nieschulzi genotype within the E. nieschulzi Landers isolate that we maintain.
艾美耳属（顶复门，球虫纲）包含多种不同的物种，寄生于不同宿主，可用于研究该属及其物种的共同特征和可变特征。所有已知艾美耳属物种的一个共同特征是卵囊，它是生命周期开始和结束的感染阶段。在我们的研究中，我们使用尼氏艾美耳球虫作为模式生物。这种特定于大鼠的寄生虫具有复杂的卵囊形态，并且可以进行转染，甚至在体外培养至卵囊阶段。我们想阐明与其他艾美耳属相比，这种啮齿动物艾美耳属物种中已知的卵囊壁形成蛋白是如何保留的。在新获得的基因组数据中，我们能够鉴定出与已知参与禽艾美耳属物种卵囊壁形成的gam基因直系同源的不同配子体基因。这些基因推测为单外显子基因，但cDNA分析显示转录本中存在可变剪接事件。对翻译序列的分析揭示了GAM蛋白中不同的保守基序以及不同区域，还有多态性区域。一个表达量较低的gam56基因版本的出现表明，在我们保存的尼氏艾美耳球虫兰德斯分离株中存在第二种不同的尼氏艾美耳球虫基因型。
