European journal of protistology最新文献

Molecular characterization and analysis of enoyl-CoA hydratase/isomerase family protein of Eimeria tenella 柔嫩艾美耳球虫烯酰辅酶a水合酶/异构酶家族蛋白的分子特征及分析

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-12-05 DOI: 10.1016/j.ejop.2025.126177

Shisi Zhang , Shunhai Zhu , Wenhao Huang , Qiping Zhao , Lu Wang , Hui Dong , Jenwen Wang , Yu Yu , Hongyu Han

Avian coccidiosis is an important intestinal disease caused by Eimeria spp., which leads to significant economic losses in the poultry industry. Although anticoccidial drugs can effectively control it in intensive farming, their extensive and irrational use has induced drug resistance in Eimeria species. Our previous RNA-seq study revealed differential expression of the enoyl-CoA hydratase/isomerase family protein (EtECHI) between drug-sensitive (DS) and drug-resistant Eimeria tenella strains. In this study, qPCR analysis showed that EtECHI mRNA levels were significantly upregulated in diclazuril-resistant (DZR) and maduramicin-resistant (MRR) strains compared to the DS strain. Furthermore, EtECHI transcription increased progressively with rising concentrations of MRR and DZR. Additionally, EtECHI transcript levels were significantly higher in field-isolated diclazuril-resistant strains than in the DS strain. qPCR and western blot analyses showed that EtECHI expression levels were highest in E. tenella unsporulated oocysts. Indirect immunofluorescence assays (IFA) revealed that EtECHI was primarily localized in the cytoplasm of the parasite, with additional surface distribution. An in vitro inhibition assay demonstrated that anti-rEtECHI polyclonal antibodies significantly reduced E. tenella sporozoites' invasion of DF-1 cells. These findings suggest that EtECHI may be associated with the drug resistance of E. tenella and may play a role in parasite growth and development within host cells.

禽球虫病是由艾美耳球虫引起的一种重要的肠道疾病，给家禽业造成了重大的经济损失。虽然抗球虫药物在集约化养殖中可以有效控制球虫，但其广泛和不合理的使用导致球虫产生耐药性。我们之前的RNA-seq研究显示，烯酰辅酶a水合酶/异构酶家族蛋白（EtECHI）在药物敏感（DS）和耐药的柔弱艾美球虫菌株之间的表达存在差异。在本研究中，qPCR分析显示，与DS菌株相比，dilazuril resistant （DZR）和maduramicin resistant （MRR）菌株中EtECHI mRNA水平显著上调。此外，随着MRR和DZR浓度的升高，EtECHI转录量逐渐增加。此外，在田间分离的耐双唑利菌株中，EtECHI转录物水平显著高于DS菌株。qPCR和western blot分析显示，EtECHI在无孢子的tenella卵囊中表达量最高。间接免疫荧光分析（IFA）显示，EtECHI主要定位于寄生虫的细胞质中，并有额外的表面分布。体外抑制实验表明，抗retechi多克隆抗体可显著降低tenella孢子子对DF-1细胞的侵袭。这些发现表明，EtECHI可能与线虫的耐药性有关，并可能在宿主细胞内寄生虫的生长发育中发挥作用。

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引用次数: 0

Step-by-step exploration of the diversity of the genus Bothrostoma Stokes, 1887 (Ciliophora, Armophorea) in Korea using morphological and molecular analyses 利用形态学和分子分析逐步探索Bothrostoma Stokes， 1887（纤毛蝗科，犰狳科）在韩国的多样性

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-11-24 DOI: 10.1016/j.ejop.2025.126174

Quoc Dung Nguyen, Nanda Dwi Kristanti, Novia Cahyani, Mann Kyoon Shin

The genus Bothrostoma Stokes, 1887 appears more diverse than previously reported. Recent studies have uncovered several new species, yet the full extent of its diversity remains to be revealed. In this study, we describe two new species, Bothrostoma longicilia nov. sp. and B. dextroproboscis nov. sp., collected from freshwater ponds in South Korea. Their characterization was conducted using both morphological and molecular approaches. Bothrostoma longicilia nov. sp. is distinguished by a combination of prominent caudal cilia, a short acute snout, 30–40 somatic kineties (including 11–15 postoral kineties), and cortical granules arranged in 7–8 discontinuous oblique rows between adjacent somatic kineties. Bothrostoma dextroproboscis nov. sp. is characterized by a rectangular shape, with the anterior left end terminating in a short acute snout and the right anterior end extended into a flexible proboscis, an oblong macronucleus, and an adoral zone of membranelles extending over approximately two-thirds of the body length. Molecular phylogenetic analysis based on SSU rDNA sequences supports the distinctness of these two new species and confirms the monophyly of the genus Bothrostoma.

Bothrostoma Stokes属，1887似乎比以前报道的更多样化。最近的研究发现了几个新物种，但其多样性的全部程度仍有待揭示。本文报道了韩国淡水池塘中发现的两个新种Bothrostoma longicilia 11 . sp和b.d dextroproboscis 11 . sp。利用形态学和分子方法对其进行了表征。长毛Bothrostoma longicilia 11 . sp.的特征是具有突出的尾纤毛，短而尖的口鼻，30-40个体运动（包括11-15个后运动）和在相邻体运动之间排列为7-8不连续斜行的皮质颗粒。Bothrostoma dextroproboscis 11 . sp.的特征是形状为矩形，左前端终止于短的尖嘴，右前端延伸为灵活的喙，长圆形的大核，以及一个延伸约占体长三分之二的膜区。基于SSU rDNA序列的分子系统发育分析支持这两个新种的独特性，并证实了Bothrostoma属的单系性。

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引用次数: 0

Ultrastructural data on stomatocysts of the genus Paraphysomonas (Chrysophyceae, Paraphysomonadales), including description of one new morphotype and identification of a new producer of Stomatocyst 52 副葡萄单胞菌属（chrysophyae, Paraphysomonadales）口囊的超微结构资料，包括一个新形态的描述和一个新生产者的鉴定52

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-11-24 DOI: 10.1016/j.ejop.2025.126173

Alena D. Firsova, Anna Y. Bessudova, Yelena V. Likhoshway

Among the diverse morphotypes of siliceous stomatocysts, not all producer species have been identified. Using scanning electron microscopy, we determined the species affiliation of two Paraphysomonas stomatocyst morphotypes based on the presence of species-specific siliceous scales on their surfaces. A new morphotype, Stomatocyst 514 Firsova & Bessudova, is formally described, and its relationship to Paraphysomonas circumvallata Thomsen was established on the basis of attached plate-scales. The previously described morphotype Stomatocyst 52 Duff & Smol, 1991 emend. Duff et al., 1995 is related to the species Paraphysomonas corynephora. The ecology of these two species differs considerably: cyst formation in P. circumvallata was observed in the southern basin of Lake Baikal in August at a water temperature of 14.3 °C, whereas P. corynephora formed cysts in the Angara River in May at 4.8 °C. These findings expand the potential for analyzing the biogeography of these species and may be applied to paleoclimatic reconstructions. The morphological diversity and ultrastructural features of all currently known stomatocyst morphotypes within the genus Paraphysomonas are discussed, and an updated identification key is provided.

在各种形态的硅质口囊中，并不是所有的生产种都被鉴定出来。利用扫描电镜，我们确定了两种副葡萄球菌口囊形态型的物种隶属关系，基于其表面存在物种特异性硅质鳞片。正式描述了一种新的形态，Stomatocyst 514 Firsova & Bessudova，并在附加板鳞的基础上建立了它与环vallata Thomsen副葡萄球菌的关系。先前描述的形态型口囊52 Duff &； Smol， 1991修订。Duff et al.， 1995与冠状副葡萄球菌有关。这两种物种的生态差异很大：8月在贝加尔湖南部盆地，在14.3°C的水温下，观察到环叶瓢虫的囊肿形成，而5月在安加拉河，在4.8°C的水温下，观察到环叶瓢虫的囊肿形成。这些发现扩大了分析这些物种的生物地理的潜力，并可能应用于古气候重建。讨论了目前已知的所有副葡萄球菌属口囊形态的形态多样性和超微结构特征，并提供了一个更新的识别关键。

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引用次数: 0

Seasonal effects on Chlorella sorokiniana UCAM 001 growth and physiology in flat-plate photobioreactors in Morocco's arid climate 摩洛哥干旱气候下平板光生物反应器中小球藻ucam001生长和生理的季节性影响

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-10-01 DOI: 10.1016/j.ejop.2025.126171

Aafaf Krimech , Sofyan Sbahi , Ouafa Cherifi , Abdessamad Hejjaj , Richard Mugani , Naaila Ouazzani , Martin Kerner , Brahim Oudra , Laila Mandi

This study aims to investigate the seasonal variation in growth and physiology of Chlorella sorokiniana UCAM 001 strain using annual optimization monitoring with a groundwater medium in two outdoor flat-plate photobioreactors (PBRs), which were first scaled up at the Faculty of Sciences Semlalia (Marrakech, Morocco). The culture medium was adjusted to ensure non-limiting nutrient concentrations (10 mg·L⁻¹ and 100 mg·L⁻¹ of additional phosphorus and nitrate, respectively). Temperature, light, and algal growth were monitored daily. Proline, glycine betaine, and catalase levels were measured every four days to assess the degree of algal stress. Biomass productivity increased during spring, reaching 30 mg·L⁻¹·day⁻¹ with a specific growth rate of 0.73 day⁻¹. However, no growth was observed during the summer. Physiological analysis revealed increased proline and glycine betaine levels during autumn and winter due to temperatures as low as 13 °C. In contrast, catalase concentration peaked in spring. Pearson correlation analysis indicated that nutrient limitation, together with temperature and light intensity, induced stress in C. sorokiniana, stimulating catalase production. Algal growth efficiently removed nutrients from the medium, achieving removal rates of 97 % for total phosphorus and 87 % for total nitrogen. Optimized cooling systems will improve PBR efficiency and support algal growth under extreme summer conditions.

本研究旨在利用地下水介质在两个室外平板光生物反应器（pbr）中进行年度优化监测，研究sorokiniana小球藻UCAM 001菌株生长和生理的季节变化。这两个室外平板光生物反应器是在Semlalia科学学院（Marrakech, Morocco）首次扩大规模的。调整培养基以确保非限制营养浓度（磷和硝酸盐分别为10 mg·L-1和100 mg·L-1）。每天监测温度、光照和藻类生长情况。每四天测量一次脯氨酸、甘氨酸甜菜碱和过氧化氢酶的水平，以评估藻类胁迫的程度。生物量生产力在春季增加，达到30 mg·L-1·d -1，比增长率为0.73 d -1。然而，在夏季没有观察到增长。生理分析显示，在秋季和冬季，由于温度低至13°C，脯氨酸和甘氨酸甜菜碱水平升高。过氧化氢酶浓度在春季达到峰值。Pearson相关分析表明，营养限制、温度和光照强度共同诱导了sorokiniana的胁迫，刺激了过氧化氢酶的产生。藻类生长有效地去除培养基中的营养物质，总磷和总氮的去除率分别达到97%和87%。优化的冷却系统将提高PBR效率，并在极端的夏季条件下支持藻类生长。

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引用次数: 0

Ultrastructural characterization of Amyloodinium ocellatum (Dinoflagellata): Insights into trophont morphology and parasitic mode 斑点淀粉体（鞭毛纲）的超微结构特征：滋养体形态和寄生模式的见解

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-10-01 DOI: 10.1016/j.ejop.2025.126175

Zhicheng Li , Baotun Wang , Jingyu Zhuang , Anxing Li , Fei Yin

Amyloodinium ocellatum is a parasitic dinoflagellate that infects marine fish in tropical and subtropical regions, causing significant economic losses in aquaculture. This study used light microscopy (LM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron tomography (ET) to comprehensively characterize the morphology, ultrastructure, and specialized attachment apparatus of A. ocellatum trophonts. The trophonts primarily parasitized the gill filaments of infected fish, reaching 89.8 ± 10.3 μm after 48 h of infection. Under LM, trophonts appeared as dark, spherical or pear-shaped structures that remained stationary throughout the parasitic process. SEM revealed surface folds and persistent transverse grooves, while TEM identified starch granules, lipid droplets, accumulation bodies, and microtubules. Trophonts rapidly formed rhizoids post-infection, which branched into root-hair-like projections penetrating the host epithelium. These projections functioned both as anchors and nutrient absorbers. During parasitism, trophonts induced degeneration and necrosis of host cells, leading to sloughing of epithelial cells and wound formation. ET further demonstrated that trophonts possessed numerous root-hair-like projections that deeply infiltrated host cells. This study provides the first systematic description of the morphology and ultrastructure of A. ocellatum trophonts and sheds new light on the fine structural features of the parasite's attachment apparatus.

扁淀粉是一种寄生于热带和亚热带海鱼体内的鞭毛藻，对水产养殖业造成重大经济损失。本研究利用光镜（LM）、扫描电镜（SEM）、透射电镜（TEM）、电子断层扫描（ET）等技术，全面表征了梭梭滋养体的形态、超微结构和专门附着器官。滋养体主要寄生在病鱼的鳃丝上，感染48 h后达到89.8±10.3 μm。在LM下，滋养体呈黑色球形或梨形结构，在整个寄生过程中保持静止。扫描电镜发现了表面褶皱和持续的横向沟槽，透射电镜发现了淀粉颗粒、脂滴、聚积体和微管。滋养体感染后迅速形成根状体，根状体分支成穿透寄主上皮的根毛状突起。这些突起既是锚，也是营养吸收剂。在寄生过程中，滋养体诱导宿主细胞变性和坏死，导致上皮细胞脱落和伤口形成。ET进一步证明滋养体具有大量的根毛状突起，可深入浸润宿主细胞。本研究首次系统地描述了棘球绦虫滋养体的形态和超微结构，揭示了棘球绦虫附着体的精细结构特征。

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引用次数: 0

Two new freshwater foraminiferal species (SAR, Rhizaria) from Dinaric karst caves (southeastern Europe) 欧洲东南部迪纳尔喀斯特溶洞中的两个淡水有孔虫新种（SAR，根虫属）。

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-10-01 DOI: 10.1016/j.ejop.2025.126172

Najla Baković , Ferry Siemensma , Maria Holzmann

Non-marine foraminifera are among the least-studied groups of protists due to their low population densities, patchy distribution, and spatiotemporal variability. This study investigated foraminifera from four caves within the Dinaric karst region of southeastern Europe, using both morphological and molecular methods. Our results confirm the presence of foraminifera in all examined caves. A new monothalamous foraminifer, Lacogromia cepelaki sp. nov., is described based on morphological and molecular data from Jopićeva Cave (Croatia). Three additional Lacogromia taxa are informally described from different caves. However, due to the lack of distinct morphological characteristics, their formal taxonomic description will require molecular analyses of live specimens. A further important outcome of this study is the morphological description of Spirolocammina petrae sp. nov., discovered in Miljacka II Cave (Croatia). This represents the first discovery of an agglutinated tubothalamid foraminifer adapted to a freshwater environment. As no molecular data could be obtained, its phylogenetic position remains undetermined, and further research will be necessary.

非海洋有孔虫是研究最少的原生生物群体之一，因为它们的种群密度低，分布不均匀，时空变化。本文对欧洲东南部第纳尔喀斯特地区的四个洞穴中的有孔虫进行了形态学和分子生物学的研究。我们的结果证实，在所有被检查的洞穴中都存在有孔虫。根据Jopićeva Cave （Croatia）的形态和分子资料，描述了一种新的单thalamous有孔虫Lacogromia cepelaki sp. nov.。从不同的洞穴中非正式地描述了另外三个Lacogromia分类群。然而，由于缺乏明显的形态特征，它们的正式分类描述将需要对活标本进行分子分析。本研究的另一个重要成果是在克罗地亚Miljacka II洞穴中发现的Spirolocammina peae sp. nov.的形态描述。这是首次发现一种适应淡水环境的凝集管状有孔虫。由于没有获得分子数据，其系统发育位置尚未确定，需要进一步研究。

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引用次数: 0

Diversity of protists in dryland habitats of Qatar revealed by environmental metabarcoding 环境元条形码揭示的卡塔尔旱地原生生物多样性。

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-10-01 DOI: 10.1016/j.ejop.2025.126168

Carla S.R. Huber , Luciano K. Huber , Sara H. Al-Hadidi , Talaat Ahmed , Sakeenah Adenan , Jane Oja , Amjad M. Shraim , Anna Ostapenko Alatalo , Mohammed Alsafran , Leho Tedersoo , Dana A. Abumaali , Laura R.P. Utz , Juha M. Alatalo

We investigated soil protist communities across five sites representing two characteristic dryland habitats in Qatar: rawdha and sabkha. Altogether, 100 samples were collected during a single field campaign; DNA was subsequently extracted, and the V4 region of the 18S rRNA gene was amplified. We obtained 112,529 high-quality sequences, taxonomically representing 1,524 TSAR (Telonemia, Stramenopila, Alveolata, Rhizaria) amplicon sequence variants. This approach enabled detection of diverse eukaryotic lineages and facilitated assessment of their diversity and relative abundance. Protist diversity differed significantly between habitats and among samples, while richness varied significantly between habitats. Across all samples, 170 genera were identified, of which 52 were shared across all sites. Sabkha exhibited the highest number of exclusive genera (22), nearly three times the number found in any individual rawdha site. The clade Alveolata accounted for 50 % or more of overall genus richness in most samples. Among ciliates, the classes Spirotrichea and Colpodea were the most abundant at the time of sampling. Functional analysis revealed consumers as the dominant trophic group. This study advances our understanding of microbial life in extremely hot environments by uniquely comparing two proximate terrestrial habitats that, despite similar climatic conditions, exhibit distinct edaphic and physicochemical characteristics.

我们调查了五个地点的土壤原生生物群落，代表了卡塔尔两种典型的旱地栖息地：rawdha和sabkha。在一次实地活动中总共收集了100个样本；随后提取DNA，扩增18S rRNA基因的V4区。我们获得了112529个高质量序列，在分类上代表1524个TSAR （Telonemia, Stramenopila, Alveolata, Rhizaria）扩增子序列变异。这种方法能够检测到不同的真核生物谱系，并有助于评估它们的多样性和相对丰度。原生生物多样性在不同生境和不同样品间差异显著，丰富度在不同生境间差异显著。在所有样本中，鉴定出170个属，其中52个属在所有站点共享。Sabkha表现出最多的专属属（22个），几乎是任何单个rawdha遗址的3倍。在大多数样本中，肺泡枝占总属丰富度的50%或更多。在纤毛虫中，取样时最多的是螺旋体纲和阴道纲。功能分析显示，消费者是主要的营养群体。本研究通过独特地比较两种近地陆地栖息地，提高了我们对极端高温环境中微生物生命的理解，尽管气候条件相似，但它们表现出截然不同的土壤和物理化学特征。

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引用次数: 0

Comparative genomics reveals insights into the ultrafast Ca2+-dependent cell contraction in ciliates (Eukaryota, SAR, Alveolata) 比较基因组学揭示了纤毛虫（真核生物，SAR，肺泡动物）中Ca2+依赖性细胞的超快收缩

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-09-18 DOI: 10.1016/j.ejop.2025.126167

Ying Zhang , Fasheng Liang , Chunying Xu , Alan Warren , Lifang Li

Certain ciliate taxa possess a Ca²⁺-dependent mechanism for ultrafast contraction, in addition to the more common adenosine triphosphate (ATP)-dependent process. In this study, we integrated omics data from 47 ciliate species, focusing on four target ciliate taxa: Vorticellidae, Zoothamniidae, Stentor, and Spirostomum. The spasmin gene, which encodes a key calcium-binding protein, was detected in 17 oligohymenophoreans (13 peritrichs, two peniculians, and two scuticociliatians) and three heterotricheans (one Stentor and two Spirostomum species). Gene family analysis revealed a roughly proportional relationship between genome/transcriptome size and the number of expanded gene families in these four target taxa. Functional enrichment analyses of significantly expanded gene families indicated rapid evolution of genes associated with phosphatase activity, dephosphorylation, signal transduction, metabolism, and transport. These findings provide new insights into the genomic adaptations underlying the unique contractile mechanisms of these ciliates.

除了更常见的三磷酸腺苷（ATP）依赖过程外，某些纤毛虫类群还具有Ca2+依赖的超快收缩机制。在这项研究中，我们整合了47种纤毛虫的组学数据，重点关注了4个目标纤毛虫类群：Vorticellidae， Zoothamniidae， Stentor和Spirostomum。在17种少膜蜂类（13种周膜蜂、2种青霉蜂和2种丝虫蜂）和3种异毛蜂类（1种Stentor和2种Spirostomum）中检测到编码关键钙结合蛋白的spasmin基因。基因家族分析显示，基因组/转录组大小与这四个目标分类群中扩增的基因家族数量大致成正比关系。功能富集分析表明，与磷酸酶活性、去磷酸化、信号转导、代谢和运输相关的基因进化迅速。这些发现为这些纤毛虫独特的收缩机制背后的基因组适应提供了新的见解。

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引用次数: 0

Morphogenesis of the anaerobic ciliate Tropidoatractus levanderi (Ciliophora, Armophorea, Metopida), with notes on conjugation and molecular phylogeny 厌氧纤毛虫troidatractus leanderi（纤毛虫目，纤毛虫目，Metopida目）的形态发生及其偶联和分子系统发育的注释

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-09-15 DOI: 10.1016/j.ejop.2025.126166

Xiaochen Feng , Wenbao Zhuang , Ran Li , Xiaozhong Hu

Tropidoatractidae, a recently established anaerobic family of metopid ciliates, have not yet been examined from a morphogenetic perspective. In this study, the interphase morphology, morphogenesis during binary fission, and body and certain nuclear changes during conjugation were investigated in a Chinese population of Tropidoatractus levanderi Rotterová et al., 2018 using the protargol impregnation method. The main findings are as follows: (1) the Chinese population closely resembles Czech and Brazilian populations, with the exception of a diplostichomonad type of paroral membrane, a feature previously overlooked; (2) divisional morphogenesis follows the metopid mode, providing further evidence for conserved cell division patterns within metopids, and (3) conjugation is of the total isogamontic type, a rare phenomenon among ciliates. Additionally, 18S rRNA gene sequence comparison and phylogenetic analyses were conducted to complement the morphological observations.

棘毛纤毛虫科是最近才建立的厌氧类纤毛虫科，但尚未从形态发生的角度进行研究。本研究采用protargol浸染法，对2018年中国鹿角蛙（Tropidoatractus levanderi rotterovi）居群的间期形态、二元裂变过程中的形态发生以及偶联过程中体和部分核的变化进行了研究。主要发现如下：(1)中国人群与捷克和巴西人群非常相似，除了口腔旁膜的diplostichomonad类型，这是一个以前被忽视的特征；(2)细胞的分裂形态发生遵循胞顶体模式，这进一步证明了胞顶体内细胞分裂模式的保守性；(3)偶联是完全等配型的，这在纤毛虫中是罕见的现象。此外，还进行了18S rRNA基因序列比较和系统发育分析，以补充形态学观察。

引用次数: 0

Typical and atypical cell division versus potential meiosis and sex in euglenids 真核细胞的典型和非典型细胞分裂与潜在减数分裂和性别

IF 1.6 2区生物学 Q4 MICROBIOLOGY

European journal of protistology

Pub Date : 2025-08-01 DOI: 10.1016/j.ejop.2025.126164

Andrej Jedlička , Olivier Barth , Diana Lihanová Bugajdová , Terézia Beck , Vanessa Gelanová , Juraj Krajčovič , Dominika Vešelényiová , Matej Vesteg

Euglenids typically reproduce asexually by closed intranuclear orthomitosis and longitudinal cell division. The nucleus divides without the dissolution of the nuclear envelope, and the spindle is radially symmetric. Typical longitudinal cell division begins in the reservoir at the anterior end of the cell and the shape of the dividing cell gradually changes from a “Y” to a “V”. This paper reviews typical mitosis and cytokinesis in euglenids, alongside atypical cell division, in which a single cell produces more than two daughter cells, forming distinctive star-like structures. Atypical cell division is particularly observed under specific stress conditions, such as exposure to chemical substances (e.g., phenol and xylene), and in senescent cultures. Although euglenids are generally considered to be asexual, the presence of key meiotic genes in Euglena gracilis suggests the potential for sexual reproduction. Bioinformatic analyses and experimental approaches, including flow cytometry and fluorescence in situ hybridization (FISH), are discussed as potential methods for detecting meiosis, sex, and cell fusion in euglenids. This review contributes to a broader understanding of both typical and atypical cell division in euglenids and underscores the need for further research into these processes, including the possible occurrence of meiosis and sexual reproduction.

真核体通常通过核内正丝分裂和纵向细胞分裂进行无性繁殖。核分裂时不溶解核膜，纺锤体呈径向对称。典型的纵向细胞分裂始于细胞前端的贮液区，分裂细胞的形状由“Y”形逐渐变为“V”形。本文综述了真核细胞中典型的有丝分裂和细胞质分裂，以及非典型细胞分裂，其中单个细胞产生两个以上的子细胞，形成独特的星形结构。在特定的应激条件下，如暴露于化学物质（如苯酚和二甲苯）和衰老培养物中，特别观察到非典型细胞分裂。虽然一般认为真核菊属植物是无性的，但存在的关键减数分裂基因表明真核菊属植物可能有性生殖。生物信息学分析和实验方法，包括流式细胞术和荧光原位杂交（FISH），讨论了作为检测真核细胞减数分裂、性别和细胞融合的潜在方法。这一综述有助于更广泛地了解真核细胞的典型和非典型细胞分裂，并强调需要进一步研究这些过程，包括减数分裂和有性生殖的可能发生。

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引用次数: 0