Schmidt Hanno, Mauer Katharina, Hankeln Thomas, Herlyn Holger
Anthropology, Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg University Mainz, Mainz, Germany.
Molecular Genetics and Genomic Analysis, Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg University Mainz, Mainz, Germany.
Cell Biosci. 2022 May 31;12(1):75. doi: 10.1186/s13578-022-00818-2.
A central question in parasitology is why parasites mature and reproduce in some host species but not in others. Yet, a better understanding of the inability of parasites to complete their life cycles in less suitable hosts may hold clues for their control. To shed light on the molecular basis of parasite (non-)maturation, we analyzed transcriptomes of thorny-headed worms (Acanthocephala: Pomphorhynchus laevis), and compared developmentally arrested worms excised from European eel (Anguilla anguilla) to developmentally unrestricted worms from barbel (Barbus barbus).
Based on 20 RNA-Seq datasets, we demonstrate that transcriptomic profiles are more similar between P. laevis males and females from eel than between their counterparts from barbel. Impairment of sexual phenotype development was reflected in gene ontology enrichment analyses of genes having differential transcript abundances. Genes having reproduction- and energy-related annotations were found to be affected by parasitizing either eel or barbel. According to this, the molecular machinery of male and female acanthocephalans from the eel is less tailored to reproduction and more to coping with the less suitable environment provided by this host. The pattern was reversed in their counterparts from the definitive host, barbel.
Comparative analysis of transcriptomes of developmentally arrested and reproducing parasites elucidates the challenges parasites encounter in hosts which are unsuitable for maturation and reproduction. By studying a gonochoric species, we were also able to highlight sex-specific traits. In fact, transcriptomic evidence for energy shortage in female acanthocephalans associates with their larger body size. Thus, energy metabolism and glycolysis should be promising targets for the treatment of acanthocephaliasis. Although inherently enabling a higher resolution in heterosexuals, the comparison of parasites from definitive hosts and less suitable hosts, in which the parasites merely survive, should be applicable to hermaphroditic helminths. This may open new perspectives in the control of other helminth pathogens of humans and livestock.
寄生虫学中的一个核心问题是，为什么寄生虫能在某些宿主物种中成熟并繁殖，而在其他宿主物种中却不能。然而，更好地理解寄生虫在不太适宜的宿主中无法完成其生命周期的原因，可能为寄生虫的控制提供线索。为了阐明寄生虫（非）成熟的分子基础，我们分析了棘头虫（棘头虫纲：平滑多形棘头虫）的转录组，并将从欧洲鳗鲡（欧洲鳗）中取出的发育停滞的虫体与从鲤科鱼（鲤）中取出的发育不受限的虫体进行了比较。
基于20个RNA测序数据集，我们证明，来自鳗鲡的平滑多形棘头虫雌雄个体之间的转录组图谱比来自鲤科鱼的对应个体之间更为相似。在对具有差异转录丰度的基因进行的基因本体富集分析中，反映了性表型发育的受损情况。发现具有繁殖和能量相关注释的基因会受到寄生在鳗鲡或鲤科鱼中的影响。据此，来自鳗鲡的棘头虫雌雄个体的分子机制对繁殖的适应性较低，而更多地是为了应对该宿主提供的不太适宜的环境。在其终末宿主鲤科鱼的对应个体中，情况则相反。
对发育停滞和繁殖的寄生虫的转录组进行比较分析，阐明了寄生虫在不适宜成熟和繁殖的宿主中所面临的挑战。通过研究一种雌雄异体物种，我们还能够突出性别特异性特征。事实上，雌性棘头虫能量短缺的转录组证据与其更大的体型相关。因此，能量代谢和糖酵解应该是治疗棘头虫病的有前景的靶点。尽管在异性个体中固有地能够实现更高的分辨率，但对来自终末宿主和不太适宜宿主（寄生虫仅在其中存活）的寄生虫进行比较，应该适用于雌雄同体的蠕虫。这可能为控制人类和家畜的其他蠕虫病原体开辟新的视角。
