No shot in the dark: Myxozoans chemically detect fresh fish
No shot in the dark: Myxozoans chemically detect fresh fish
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DOI：
10.1016/j.ijpara.2010.09.012
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发表时间：
2011-03-01
影响因子：
4
通讯作者：
El-Matbouli, Mansour
中科院分区：
文献类型：
--
作者：
Kallert, Dennis M.;Bauer, Walter;El-Matbouli, Mansour
这项工作报告了一种迄今为止未知的化学识别特性的发现，使水生栖息地的寄生生命周期成为可能。我们相信，这是首次发现一种天然的、宿主衍生的化学分子，被认为是黏液动物门的识别线索。这些寄生虫的放线菌孢子通过极性细丝附着在鱼类宿主上，这些极性细丝是在预先识别表面黏液中含有的化学触发器后，在机械刺激下挤出的。我们的目标是识别这个信号。采用高效液相色谱法分离了鳟鱼黏液中纯化的活性组分。随后，通过核磁共振分析和生物测定，我们诱导了3种黏液动物（黏液动物Myxobolus cerebralis、Myxobolus pseudodispar和Henneguya nuesslini）放线菌孢子中游离核苷肌苷、2′-脱氧肌苷和鸟苷对极丝放电和孢子质释放的刺激。这些核苷也激活了孢子质发射。核苷似乎是水传播寄生虫阶段快速识别宿主的适当线索，因为它们不断释放到表面粘液中。这种识别机制对敏感宿主物种并不是特异性的，至少在黏液动物中是这样。此外，还发现了核碱基衍生物作为半化学物质的新功能，并预测了这类分子在寄生虫识别系统和水生化学生态学中的更广泛影响。疾病预防和细胞培养的相关性仍有待探索。(C) 2010年澳大利亚寄生虫学学会Elsevier Ltd.出版。版权所有。
This work reports the discovery of an hitherto unknown chemical recognition trait enabling a parasitic life cycle in aquatic habitats. We believe this is the first record of a natural, host-derived chemical molecule identified as a recognition cue for the phylum Myxozoa. The actinospores of these parasites attach to fish hosts via polar filaments that are extruded upon mechanical stimulation after preceding recognition of a chemical trigger contained in surface mucus. Our goal was to identify this signal. We separated compounds from a purified active fraction derived from trout mucus by a novel HPLC method. By subsequent nuclear magnetic resonance analysis of distinct components and testing in bioassays we elicited stimulation of polar filament discharge and sporoplasm emission in actinospores of three myxozoan spp., Myxobolus cerebralis, Myxobolus pseudodispar and Henneguya nuesslini, by the free nucleosides inosine, 2'-deoxyinosine and guanosine. These nucleosides also activated sporoplasm emission. Nucleosides appear to be appropriate cues for rapid host recognition by the waterborne parasite stages since they are continuously released into surface mucus. The recognition mechanism is not specific for susceptible host species, at least in the myxozoan spp. examined. In addition, a novel function of nucleobase derivatives as semiochemicals was uncovered and a wider impact of this molecule class in parasite recognition systems and aquatic chemical ecology is predicted. The relevance for disease prevention and cell culturing remains to be explored. (C) 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.