Environmental and Molecular Biosciences, University of Swansea, Singleton Park, Swansea SA2 8PP, UK.
Eur J Protistol. 2010 Jan;46(1):17-28. doi: 10.1016/j.ejop.2009.10.002. Epub 2009 Nov 17.
In the absence of distinct morphological characteristics, knowledge of genetic relationships within and between protist parasite species is important for determining reservoir hosts and understanding the biology of the causative agents of emerging diseases. The genus Hematodinium is a member of Syndinea, an ubiquitous alveolate group found in all oceanic environments. Hematodinium parasites cause epizootics in crustaceans, yet their life cycle, genotypic variety and their phylogeny is poorly understood. By combining phylogenetic methods with analyses of secondary structures of variable ribosomal RNA genes we show that Hematodinium from the east and west North-Atlantic is comprised of distinct ribotypes or clades. These did not correspond to a specific area, but varied in host specificity. For example, a Hematodinium 'Langoustine' clade was only found in Nephrops norvegicus langoustines, whereas other clades were specific to crabs or seem to be generalist parasites.
在缺乏明显形态特征的情况下，了解原生动物寄生虫种内和种间的遗传关系对于确定储存宿主和理解新出现疾病病原体的生物学特性非常重要。Hematodinium 属是 Syndinea 的成员， Syndinea 是一种普遍存在的有孔虫类，存在于所有海洋环境中。Hematodinium 寄生虫会导致甲壳类动物爆发疾病，但它们的生命周期、基因型多样性及其系统发育仍知之甚少。通过将系统发育方法与可变核糖体 RNA 基因二级结构分析相结合，我们发现北大西洋东部和西部的 Hematodinium 由不同的核糖体型或分支组成。这些分支与特定区域无关，而是宿主特异性不同。例如，只在挪威海螯虾中发现了 Hematodinium“Langoustine”分支，而其他分支则是特定于螃蟹或似乎是寄生虫的广义种。
