Yazaki Euki, Harada Ryo, Isogai Ryu, Bamba Kohei, Ishida Ken-Ichiro, Inagaki Yuji, Shiratori Takashi
National Agriculture and Food Research Organization Advanced Analysis Center, Tsukuba, Ibaraki Prefecture, Japan.
iTEMS, RIKEN, Wako, Saitama Prefecture, Japan.
Open Biol. 2025 Jun;15(6):250057. doi: 10.1098/rsob.250057. Epub 2025 Jun 4.
Culturing protists offers a powerful approach to exploring eukaryotic diversity, especially for deep-branching lineages. In this study, we cultured and described a novel protist species, named n sp. within the poorly studied and unclassified genus . While an SSU rDNA gene phylogeny failed to resolve its phylogenetic placement in the eukaryotic tree, a phylogenomic analysis of 340 proteins indicated as a member of the CRuMs clade. Prior to this study, this clade consisted of diverse heterotrophic amoeba and flagellates, and lacked clear synapomorphies. Ultrastructural observations revealed that shares the characteristics with some CRuMs members, including the pellicle underlying the plasma membrane and an internal sleeve surrounding the central pair of the axoneme at the flagellar transitional region. Our findings suggest potential shared characteristics and synapomorphies for CRuMs and contribute to a deeper understanding of the character evolution within this clade.
培养原生生物为探索真核生物多样性提供了一种强有力的方法，特别是对于分支较深的谱系。在本研究中，我们培养并描述了一种新型原生生物物种，命名为n sp.，它属于研究较少且未分类的属。虽然基于小亚基核糖体DNA（SSU rDNA）基因的系统发育未能确定其在真核生物树中的系统发育位置，但对340种蛋白质的系统基因组分析表明它是CRuMs进化枝的一员。在本研究之前，这个进化枝由各种异养变形虫和鞭毛虫组成，并且缺乏明确的共衍征。超微结构观察表明，n sp.与一些CRuMs成员具有共同特征，包括质膜下方的表膜以及鞭毛过渡区围绕轴丝中央对的内部套筒。我们的研究结果表明CRuMs可能具有共同特征和共衍征，并有助于更深入地了解该进化枝内的性状进化。
