Phylogeny, Evidence for a Cryptic Plastid, and Distribution of Chytriodinium Parasites (Dinophyceae) Infecting Copepods.
Phylogeny, Evidence for a Cryptic Plastid, and Distribution of Chytriodinium Parasites (Dinophyceae) Infecting Copepods.
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感染桡足类的壶菌寄生虫（甲藻纲）的系统发育、隐性质体的证据和分布。
DOI：
10.1111/jeu.12701
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发表时间：
2019
期刊：
影响因子：
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通讯作者：
Strassert JFH
中科院分区：
文献类型：
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作者：
Strassert JFH
已知的是，甲藻的孢子侵染了桡足类的卵，导致了它们的致死。尽管有可能控制这种具有重要生态意义的寄主的种群数量，但有关寄生线虫的知识有限：我们对系统发育、寄生、丰度或地理分布知之甚少。我们对来自同一孢子囊的4个人工分离的孢子细胞进行了基因组序列测定，以分析基于SSU和连接的SSU/LSU rRNA基因序列的尺足类无节幼虫的系统发育地位，并分析了与质质血红素途径相关的两个基因hemLandhemY。这些结果表明，寄生的寄生植物存在一种隐匿的质体和一种光合作用的祖先状态。最后，通过将TaraOcean V9 SSU扩增数据与从孢子细胞中恢复的SSU rRNA基因序列进行映射，我们表明，在全球范围内，鞭毛虫寄生虫在表层海洋的微微/纳米和中游浮游生物中最为丰富，而在微型浮游生物中几乎不存在，这一分布表明它们通常以自由生活的孢子或寄主相关的孢子囊存在。
Spores of the dinoflagellateChytriodiniumare known to infest copepod eggs causing their lethality. Despite the potential to control the population of such an ecologically important host, knowledge aboutChytriodiniumparasites is limited: we know little about phylogeny, parasitism, abundance, or geographical distribution. We carried out genome sequence surveys on four manually isolated sporocytes from the same sporangium, which seemed to be attached to a copepod nauplius, to analyze the phylogenetic position ofChytriodiniumbased on SSU and concatenated SSU/LSU rRNA gene sequences, and also characterize two genes related to the plastidial heme pathway,hemLandhemY. The results suggest the presence of a cryptic plastid inChytriodiniumand a photosynthetic ancestral state of the parasiticChytriodinium/Dissodiniumclade. Finally, by mappingTaraOceans V9 SSU amplicon data to the recovered SSU rRNA gene sequences from the sporocytes, we show that globally,Chytriodiniumparasites are most abundant within the pico/nano‐ and mesoplankton of the surface ocean and almost absent within microplankton, a distribution indicating that they generally exist either as free‐living spores or host‐associated sporangia.