Protist最新文献 - Book学术

Piercing the veil: A novel amoebozoan (Janelia veilia n. gen. n. sp.) reveals deep clades within Discosea through phylogenomics 揭开面纱：一种新的变形虫（Janelia veilia n. gen. n. sp.）通过系统基因组学揭示了Discosea内部的深层分支

IF 1.9 3区生物学

Protist Pub Date : 2025-05-03 DOI: 10.1016/j.protis.2025.126103

Robert E. Jones , Quentin Blandenier , Felicity Kleitz-Singleton , Tristan C. Henderson , Nicholas W. Fry , Idan Banson , Jonah Nguyen , Alexander K. Tice , Matthew W. Brown

{"title":"Piercing the veil: A novel amoebozoan (Janelia veilia n. gen. n. sp.) reveals deep clades within Discosea through phylogenomics","authors":"Robert E. Jones , Quentin Blandenier , Felicity Kleitz-Singleton , Tristan C. Henderson , Nicholas W. Fry , Idan Banson , Jonah Nguyen , Alexander K. Tice , Matthew W. Brown","doi":"10.1016/j.protis.2025.126103","DOIUrl":"10.1016/j.protis.2025.126103","url":null,"abstract":"<div><div>Three major groups of primarily amoeboid taxa are present across Amoebozoa: Discosea, Evosea, and Tubulinea. While each of these groups were thought to have morphologically unique traits and members, the morphologic boundaries between each group have recently blurred. For example, it is demonstrated that several taxa in each group display monopodial limax amoebae, a characteristic most often associated with Tubulinea. Here we describe a novel discosean amoeba isolated from a freshwater pond, <em>Janelia veilia</em> n. gen. n. sp. Its cells have variable morphologies, but often display monopodial limax amoebae, with a unique trailing structure that appears to be derived from cellular material. In some cases, cells have conical pseudopodia or pointed pseudopodia. Using phylogenomics, we find that this taxon branches as sister to the recently described discosean <em>Mycamoeba gemmipara</em> and the sporocarpic protosteloid amoeba <em>Microglomus paxillus</em>, forming an order-level group we term Mycamoebida. Mycamoebida is fully supported as sister to Dermamoebida, together forming a subclass we term Dermelia. SSU rRNA phylogenies show that <em>Janelia veilia</em> n. gen. n. sp. is molecularly unique from any known organism, but branches with high support in a clade containing <em>Mycamoeba gemmipara</em> and several environmental sequences suggesting a larger diverse clade within Discosea.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126103"},"PeriodicalIF":1.9,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transcriptomic analyses reveal sexual cues in reproductive life stages of uncultivated Acantharia (Radiolaria) 转录组学分析揭示了未栽培棘虫（Radiolaria）生殖阶段的性暗示

IF 1.9 3区生物学

Protist Pub Date : 2025-04-28 DOI: 10.1016/j.protis.2025.126102

Iris Rizos , Sarah Romac , Caroline Juery , Charlotte Berthelier , Johan Decelle , Juliana Bernardes , Erwan Corre , Lucie Bittner , Fabrice Not

{"title":"Transcriptomic analyses reveal sexual cues in reproductive life stages of uncultivated Acantharia (Radiolaria)","authors":"Iris Rizos , Sarah Romac , Caroline Juery , Charlotte Berthelier , Johan Decelle , Juliana Bernardes , Erwan Corre , Lucie Bittner , Fabrice Not","doi":"10.1016/j.protis.2025.126102","DOIUrl":"10.1016/j.protis.2025.126102","url":null,"abstract":"<div><div>The ability to reproduce is a key process for the perpetuation of organisms. Along the evolution of protist reproductive strategies, the molecular machinery of sexual recombination is estimated to have been inherited from the last eukaryotic common ancestor (LECA). Unraveling the sexual cycles of free-living protists remains challenging, given the enigmatic roles of many uncultivated life stages. For the planktonic group of Acantharia (Radiolaria), a hypothetical sexual cycle has been proposed since the late 19th century, including a gamete-like stage, referred to as swarmers. In order to investigate the sexual nature of acantharian reproductive stages, we compared transcriptomes of various acantharian life stages. Our results show distinct functional profiles for reproductive and vegetative stages, while revealing the expression of the gamete fusion genes, HAP2/GCS1 and KAR5-GEX1-BMB in swarmers. Annotation of differentially expressed life stage-specific genes, also highlighted putative meiosis-related functions among pre-swarmer and swarmer stages, while suggesting the existence of a putative zygotic stage. This original life stage-specific genetic data is coherent with morphological evidence supporting the acantharian sexual cycle, with swarmers acting as gametes. Moreover, it paves the way for a deeper understanding of radiolarian cell biology and ecology at a single-cell scale.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126102"},"PeriodicalIF":1.9,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143928096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unveiling the remarkable diversity of the genus Hypotrichomonas (Parabasalia: Hypotrichomonadidae) in cockroaches (Blattodea, excluding Isoptera) 揭示蟑螂（小蠊总目，不包括等翅目）中滴虫属（副滴虫目：滴虫科）的显著多样性

IF 1.9 3区生物学

Protist Pub Date : 2025-04-15 DOI: 10.1016/j.protis.2025.126100

Michael Kotyk , Zuzana Kotyková Varadínová , Pavla Hrubá , Ivan Čepička

{"title":"Unveiling the remarkable diversity of the genus Hypotrichomonas (Parabasalia: Hypotrichomonadidae) in cockroaches (Blattodea, excluding Isoptera)","authors":"Michael Kotyk , Zuzana Kotyková Varadínová , Pavla Hrubá , Ivan Čepička","doi":"10.1016/j.protis.2025.126100","DOIUrl":"10.1016/j.protis.2025.126100","url":null,"abstract":"<div><div>Parabasalid hindgut symbionts of the xylophagous Isoptera/<em>Cryptocercus</em> lineage (Blattodea: Blattoidea) have been attracting the interest of biologists for decades. However, the parabasalids from other cockroaches (Blattodea excluding Isoptera) remain largely unstudied. The genus <em>Hypotrichomonas</em>, along with genus <em>Trichomitus</em>, belongs to the small parabasalid order Hypotrichomonadida. So far, ten valid <em>Hypotrichomonas</em> species have been described from animals, both vertebrates and invertebrates. Here we have uncovered an extensive diversity of this genus in cockroaches. We have obtained 72 isolates from 41 cockroach species and one from a water-filled tree hole. Using a combination of light-microscopic morphology of protargol-stained cells, scanning electron microscopy, and a phylogenetic analysis of SSU rRNA gene, we show that our strains represent multiple novel <em>Hypotrichomonas</em> species, and we formally describe seven of them. Our data show that the evolutionary center of the genus likely lies in cockroaches. Moreover, the new evolutionary lineages of <em>Hypotrichomonas</em> from cockroaches show a high degree of host specificity.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126100"},"PeriodicalIF":1.9,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel free-living endomyxan flagellate Viscidocauda repens gen. Nov., sp. nov 一种新的自由生活的内生鞭毛软尾纲动物，repens gen. Nov., sp. Nov.

IF 1.9 3区生物学

Protist Pub Date : 2025-04-14 DOI: 10.1016/j.protis.2025.126101

Takashi Shiratori, Ken-ichiro Ishida

引用次数: 0

Morphology and phylogeny of Prorocentrum venetum Tolomio & Cavolo (Dinophyceae) 龙足科原中央兽类的形态与系统发育

IF 1.9 3区生物学

Protist Pub Date : 2025-04-03 DOI: 10.1016/j.protis.2025.126099

Daniel Grzebyk , Mona Hoppenrath , Urban Tillmann

{"title":"Morphology and phylogeny of Prorocentrum venetum Tolomio & Cavolo (Dinophyceae)","authors":"Daniel Grzebyk , Mona Hoppenrath , Urban Tillmann","doi":"10.1016/j.protis.2025.126099","DOIUrl":"10.1016/j.protis.2025.126099","url":null,"abstract":"<div><div><em>Prorocentrum venetum</em> was one of the first species of the genus <em>Prorocentrum</em> described by scanning electron microscopy by Tolomio and Cavolo in 1985. Since the first observation of the species in the Venice Lagoon (Italy) in summer 1981, it has not been reported again in published phytoplankton records of Mediterranean waters or elsewhere. Two strains were isolated from a French Mediterranean lagoon, which were morphologically identified as <em>P. venetum</em> by microscopy. Based on rDNA sequences (spanning the 18S to the D3 region of 28S rDNA), the phylogenetic analysis demonstrated that <em>P. venetum</em> belongs to the same clade as <em>Prorocentrum triestinum</em> and <em>Prorocentrum redfieldii</em>. The analysis of scanning electron micrographs provided an in-depth morphological description of the theca, particularly on the pore pattern of thecal plates and new structural details of the platelets in the periflagellar area. These morphological characteristics were compared with the closely related species within the <em>P. triestinum</em> clade, which showed synapomorphic characters in the periflagellar area (small accessory pore, platelet pattern, shape of the apical wing). Further comparison of characteristics varying between species in this clade and in the sister clade encompassing species related to <em>Prorocentrum micans</em> suggests some features of morphological evolution within this part of the genus.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126099"},"PeriodicalIF":1.9,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Morphology and taxonomy of a new species of a rare genus Paracolpidium (Ciliophora, Oligohymenophorea), P. harbinense sp. nov. from Northeast China 东北疏膜蜂属一新种的形态与分类

IF 1.9 3区生物学

Protist Pub Date : 2025-03-25 DOI: 10.1016/j.protis.2025.126097

Xiang Wang , Bailin Li , Jiarui Wang, Xiaosong Wang, Jialu Wang, Xuming Pan

引用次数: 0

Alexandrium minutum strains from a recombinant cross show correlated allelopathic activity against the diatom Chaetoceros muelleri and the parasite Amoebophrya sp., independent of PST toxicity. 重组杂交的微小亚历山大菌菌株对硅藻毛囊毛藻和寄生虫变形虫具有相关的化感作用，与PST毒性无关。

IF 1.9 3区生物学

Protist Pub Date : 2025-03-19 DOI: 10.1016/j.protis.2025.126098

Lou Mary , Marie Latimier , Joelle Serghine , Julien Quere , Véronique Savar , Sébastien Artigaud , Damien Réveillon , Mickael Le Gac , Cécile Jauzein , Hélène Hégaret

{"title":"Alexandrium minutum strains from a recombinant cross show correlated allelopathic activity against the diatom Chaetoceros muelleri and the parasite Amoebophrya sp., independent of PST toxicity.","authors":"Lou Mary , Marie Latimier , Joelle Serghine , Julien Quere , Véronique Savar , Sébastien Artigaud , Damien Réveillon , Mickael Le Gac , Cécile Jauzein , Hélène Hégaret","doi":"10.1016/j.protis.2025.126098","DOIUrl":"10.1016/j.protis.2025.126098","url":null,"abstract":"<div><div>Dinoflagellates of the genus <em>Alexandrium</em> can produce bioactive extracellular compounds (BECs) responsible for a wide range of effects on many organisms. These compounds are poorly characterized within the genus <em>Alexandrium</em>. The transmission of the allelopathic phenotype within the recombinant progeny in dinoflagellates has not been documented either. This study investigated the effects of these allelochemicals produced by two parental strains of the dinoflagellate <em>Alexandrium minutum</em> and their 14 recombinant progeny against two targets, the diatom <em>Chaetoceros muelleri</em> and the dinoflagellate parasite <em>Amoebophrya</em> sp.. Analyses by flow cytometry on proxy parameters of cell physiology revealed that the allelochemicals produced by 15 out of 16 strains appear to induce deleterious effects on the photosynthetic apparatus of <em>C. muelleri</em> as well as on cell size. The cell membranes of <em>C. muelleri</em> were also damaged by the filtrate of 9 strains. Finally, the allelochemicals of 8 <em>A. minutum</em> strains seem to have a deleterious effect on the cell membranes of <em>Amoebophrya</em> sp. dinospore. The deleterious effects against the two targets were correlated. However, they were not correlated with pH, cell size, or paralytic shellfish toxin content. Overall, our results suggest that 1) among the allelochemicals produced by <em>A. minutum</em>, some would have an effect on the same molecular targets in both <em>Amoebophrya</em> sp. and in <em>C. muelleri</em>, 2) specific metabolite production of each strain was responsible for the range of effects observed and 3) the heritability of allelochemical production in <em>A. minutum</em> may involve several genetic loci.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126098"},"PeriodicalIF":1.9,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Description of new diplonemids (Diplonemea, Euglenozoa) and their endosymbionts: Charting the morphological diversity of these poorly known heterotrophic flagellates 新双鞭毛纲（双鞭毛纲，真鞭毛纲）及其内共生生物的描述：绘制这些鲜为人知的异养鞭毛纲的形态多样性

IF 1.9 3区生物学

Protist Pub Date : 2025-02-20 DOI: 10.1016/j.protis.2025.126090

Daria Tashyreva , Jan Votýpka , Akinori Yabuki , Aleš Horák , Julius Lukeš

{"title":"Description of new diplonemids (Diplonemea, Euglenozoa) and their endosymbionts: Charting the morphological diversity of these poorly known heterotrophic flagellates","authors":"Daria Tashyreva , Jan Votýpka , Akinori Yabuki , Aleš Horák , Julius Lukeš","doi":"10.1016/j.protis.2025.126090","DOIUrl":"10.1016/j.protis.2025.126090","url":null,"abstract":"<div><div>Diplonemids are a hyperdiverse group of flagellated protists, but with less than two dozen formally described representatives. Here, we describe four new species of cultured diplonemids, identified on the basis of their 18S rRNA sequences, light-, fluorescence-, scanning- and transmission electron microscopy. Three new species belong to the genus <em>Rhynchopus</em> (<em>R. asiaticus</em> sp.n.<em>, R. granulatus</em> sp.n., and <em>R. valaseki</em> sp.n.), while the fourth species is an unusual representative of the genus <em>Lacrimia</em> (<em>L. aflagellata</em> sp.n.). The latter organism is the first diplonemid outside the genus <em>Rhynchopus</em> (as defined previously) to show a gliding trophic stage with flagellar stubs concealed inside the flagellar pocket and a highly motile dispersive swimming stage. Since this character is thus no longer a genus-specific apomorphy, we provide a taxonomic revision of the genus <em>Rhynchopus</em> with separation of the new genus <em>Natarhynchopus</em> gen. n<em>.</em> We also identify bacterial endosymbionts of <em>L</em>. <em>aflagellata</em> and <em>R. asiaticus</em> as <em>Ca</em>. Syngnamydia medusae (<em>Chlamydiales</em>, <em>Simkaniaceae</em>) and Ca. Cytomitobacter rhynchopi sp. n. (<em>Alphaproteobacteria</em>, <em>Holosporaceae</em>), respectively, and discuss their potential functions. This is the first report of a chlamydial symbiont within a diplonemid host. We also propose that diplonemids may serve as vectors for chlamydial pathogens of marine fish.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"177 ","pages":"Article 126090"},"PeriodicalIF":1.9,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143488035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The enigmatic genus Malacophrys Kahl, 1926 (Ciliophora: Intramacronucleata) belongs to the class Oligohymenophorea 谜一般的Malacophrys Kahl属，1926（栉蚜目：内层栉蚜目）属于少膜蜂目

IF 1.9 3区生物学

Protist Pub Date : 2025-02-14 DOI: 10.1016/j.protis.2025.126089

William Bourland, Ivan Čepička

{"title":"The enigmatic genus Malacophrys Kahl, 1926 (Ciliophora: Intramacronucleata) belongs to the class Oligohymenophorea","authors":"William Bourland, Ivan Čepička","doi":"10.1016/j.protis.2025.126089","DOIUrl":"10.1016/j.protis.2025.126089","url":null,"abstract":"<div><div>The ciliate genus <em>Malacophrys</em> has been incertae sedis for more than 50 years in what is now subphylum Intramacronucleata, provisionally assigned to three different classes by various authors. Of the three species included in the genus, <em>M. sphagni</em> and the type species, <em>Malacophrys rotans</em>, have not been studied by modern methods and <em>M. viridis</em>, although morphologically well-described, lacks molecular characterization. We identified two freshwater ciliates as morphologically consistent with two members of <em>Malacophrys</em>, namely <em>M. rotans</em> and <em>M. viridis</em>. We studied one population of <em>M. rotans</em>, using in vivo observation and silver carbonate and silver nitrate impregnation, and two populations of <em>M. viridis</em>, using in vivo observation, silver carbonate impregnation, and 18S rRNA gene sequencing. Phylogenetic analyses strongly support the position of <em>M. viridis</em> in the class Oligohymenophorea. Morphologic features suggest <em>Malacophrys rotans</em> belongs to order Tetrahymenida, but a confident phylogenetic assignment awaits its molecular sequencing. Differences between their oral structures and silverline patterns indicate that <em>M. rotans</em> and <em>M. viridis</em> likely belong to different genera. A formal separation at the genus level awaits molecular characterization of the type species, <em>M. rotans</em>.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"176 ","pages":"Article 126089"},"PeriodicalIF":1.9,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterization of the encystment-inducing activity of extracellular fluid from encysting vegetative cells in the terrestrial ciliated protozoa Colpoda cucullus 陆地纤毛原生动物包囊营养细胞胞外液诱导包囊活性的研究

IF 1.9 3区生物学

Protist Pub Date : 2025-02-12 DOI: 10.1016/j.protis.2025.126088

Yuto Shimada , Arisa Momota , Ayumu Onda , Mikihiko Arikawa

{"title":"Characterization of the encystment-inducing activity of extracellular fluid from encysting vegetative cells in the terrestrial ciliated protozoa Colpoda cucullus","authors":"Yuto Shimada , Arisa Momota , Ayumu Onda , Mikihiko Arikawa","doi":"10.1016/j.protis.2025.126088","DOIUrl":"10.1016/j.protis.2025.126088","url":null,"abstract":"<div><div>The terrestrial ciliated protozoan <em>Colpoda cucullus</em> transforms into a dehydration-resistant cyst upon sensing adverse signals. Recently, we identified a pheromone secreted by encysting vegetative cells of <em>C. cucullus</em>, termed “encystment-inducing pheromone” (EnIP), and characterized its properties. Overpopulated vegetative cells spontaneously encysted in ion-free ultrapure water without external stimuli. The external solution of encysting cells markedly induced encystment in vegetative cells under low cell density conditions, suggesting that EnIP, secreted by encysting cells into the external solution, induced encystment in vegetative cells. Further investigations revealed the following properties of EnIP: 1) EnIP retains encystment-inducing activity even in the presence of EGTA. 2) EnIP exhibits a concentration-dependent encystment effect. 3) EnIP is released within hours at high cell density. 4) EnIP is released by exocytosis. 5) EnIP loses its activity after 1–2 days. 6) EnIP is inactivated by heating and treatment with proteolytic enzymes. 7) The nominal molecular weight of EnIP was estimated to range between 10 and 100 kDa. These findings lead to the conclusion that encystment-induced <em>C. cucullus</em> vegetative cells secrete EnIP, a protein pheromone, with encystment-inducing activity for other cells. This study contributes to understanding microbial communication and reveals a novel mechanism for protist survival in harsh environments.</div></div>","PeriodicalId":20781,"journal":{"name":"Protist","volume":"176 ","pages":"Article 126088"},"PeriodicalIF":1.9,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143436443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0