Journal of Eukaryotic Microbiology最新文献_第2页

HCN channels are essential for the escape response of Paramecium. HCN通道对鹦鹉螺的逃逸反应至关重要。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-28 DOI: 10.1111/jeu.13057

Daisuke Kandabashi, Mutsumi Kawano, Shinobu Izutani, Hiyori Harada, Takashi Tominaga, Manabu Hori

{"title":"HCN channels are essential for the escape response of Paramecium.","authors":"Daisuke Kandabashi, Mutsumi Kawano, Shinobu Izutani, Hiyori Harada, Takashi Tominaga, Manabu Hori","doi":"10.1111/jeu.13057","DOIUrl":"https://doi.org/10.1111/jeu.13057","url":null,"abstract":"When mechanical stimulation was applied to free swimming Paramecium, forward swimming velocity transiently increased due to activation of the posterior mechanosensory channels. The behavior response, known as \"escape response,\" requires membrane hyperpolarization and the activation of K-channel type adenylate cyclases. Our hypothesis is that this escape response also involves activation of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels. HCN channels are activated by hyperpolarization and are modulated by cyclic nucleotides such as cAMP and cGMP. They play a critical role in many excitable cells in higher animals. If HCN channels act in Paramecium, this should help to enhance and prolong hyperpolarization, thereby increasing the swimming speed of Paramecium. This study used RNAi to examine the role of the HCN channel 1 in the escape responses by generating hcn1-gene knockdown cells (hcn1-KD). These cells showed reduced mechanically-stimulated escape responses and a lack of cGMP-dependent increases in swimming speed. Electrophysiological experiments demonstrated reduced hyperpolarization upon injection of large negative currents in hcn1-KD cells. This is consistent with a decrease in HCN1 channel activity and changes in the escape response. These findings suggest that HCN1 channels are K+ channels that regulate the escape response of Paramecium by amplifying the hyperpolarizations elicited by posterior mechanical stimulation.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13057"},"PeriodicalIF":2.1,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142093480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Remarkable genetic variability and high antigenicity of the octapeptide-repeat region in an Entamoeba nuttalli-specific surface protein. 一种 Entamoeba nuttalli 特异性表面蛋白的八肽重复区域具有显著的遗传变异性和高度抗原性。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-19 DOI: 10.1111/jeu.13055

Tatsuya Imai, Azumi Kakino, Akitomo Sugawara, Xunjia Cheng, Hiroshi Tachibana

{"title":"Remarkable genetic variability and high antigenicity of the octapeptide-repeat region in an Entamoeba nuttalli-specific surface protein.","authors":"Tatsuya Imai, Azumi Kakino, Akitomo Sugawara, Xunjia Cheng, Hiroshi Tachibana","doi":"10.1111/jeu.13055","DOIUrl":"https://doi.org/10.1111/jeu.13055","url":null,"abstract":"Entamoeba nuttalli is genetically the closest to Entamoeba histolytica, the causative agent of human amebiasis. E. nuttalli is found in Macaca species, exhibiting no symptoms while potentially virulent. Using comparative genomics of Entamoeba species, we identified a gene encoding an E. nuttalli-specific protein containing 42 repeats of an octapeptide (PTORS). In the present study, we analyzed the genes in E. nuttalli strains derived from various geographic locations and host species. Sequence analysis of genomic DNA from four strains indicated 43, 44, and 48 repeat types in addition to 42 repeats and remarkable genetic diversity in the repeat region, although all nucleotide substitutions were synonymous. In contrast, the sequences of the N-terminal side region and C-terminus were identical among the strains. Monoclonal antibodies prepared against recombinant PTORS were reactive to the repeat regions but not to the N-terminal side regions. Polyclonal antibodies did not react with the N-terminal region, demonstrating that the repeat region had higher antigenicity. Analysis using synthetic peptides revealed that the two repeats of the octapeptide functioned as epitopes. Immunofluorescence microscopy using monoclonal antibodies demonstrated the surface localization of PTORS. These results suggest that the repeat region of PTORS plays an important role in host-parasite interactions.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13055"},"PeriodicalIF":2.1,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142000035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Special issue on microsporidia 微孢子虫特刊。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-18 DOI: 10.1111/jeu.13056

Louis M. Weiss

引用次数: 0

Editor's message. 编辑致辞

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-08 DOI: 10.1111/jeu.13054

Joel B Dacks

引用次数: 0

Molecular phylogeny of the Lecudinoidea (Apicomplexa): A major group of marine gregarines with diverse shapes, movements and hosts. 蝶形目（Apicomplexa）的分子系统发育：具有不同形状、运动方式和寄主的一个主要海洋石龙子类群。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-08 DOI: 10.1111/jeu.13053

Eunji Park, Brian S Leander

{"title":"Molecular phylogeny of the Lecudinoidea (Apicomplexa): A major group of marine gregarines with diverse shapes, movements and hosts.","authors":"Eunji Park, Brian S Leander","doi":"10.1111/jeu.13053","DOIUrl":"https://doi.org/10.1111/jeu.13053","url":null,"abstract":"Gregarine apicomplexans are ubiquitous endosymbionts of invertebrate hosts. Despite their ecological and evolutionary importance, inferences about the phylogenetic relationships of major gregarine groups, such as the Lecudinidae and Urosporidae, have been hindered by vague taxonomic definitions and limited molecular and morphological data. In this study, we investigated five gregarine species collected from four families of polychaete hosts (Nereididae, Oenonidae, Hesionidae, and Phyllodocidae) using light microscopy (LM) and scanning electron microscopy (SEM). We also generated small subunit ribosomal DNA sequences from these species and conducted molecular phylogenetic analyses to elucidate the evolutionary relationships within the Lecudinoidea. Our results include new molecular and morphological data for two previously described species (Lecudina cf. platynereidis and Lecudina cf. arabellae), the discovery of a new species of Lecudina (L. oxydromus n. sp.), and the discovery of two novel species, namely Amplectina cordis n. gen. et. n. sp. and Sphinctocystis inclina n. sp. These two species exhibited unique shapes and movements, resembling those of urosporids but with a phylogenetic affinity to lecudinids, blurring the border between lecudinids and urosporids. Our study emphasizes the need for further investigations into this highly diverse group, which has achieved great success across multiple animal phyla with diverse shapes and movements.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13053"},"PeriodicalIF":2.1,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141906774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Nosema bombycis: A remarkable unicellular parasite infecting insects Nosema bombycis：一种感染昆虫的非凡的单细胞寄生虫。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-08-02 DOI: 10.1111/jeu.13045

Qingyuan Huang, Wanying Hu, Xianzhi Meng, Jie Chen, Guoqing Pan

引用次数: 0

Life cycle strategies in free-living unicellular eukaryotes: Diversity, evolution, and current molecular tools to unravel the private life of microorganisms. 自由生活的单细胞真核生物的生命周期策略：多样性、进化和当前的分子工具，揭示微生物的私密生活。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-07-31 DOI: 10.1111/jeu.13052

Iris Rizos, Miguel J Frada, Lucie Bittner, Fabrice Not

{"title":"Life cycle strategies in free-living unicellular eukaryotes: Diversity, evolution, and current molecular tools to unravel the private life of microorganisms.","authors":"Iris Rizos, Miguel J Frada, Lucie Bittner, Fabrice Not","doi":"10.1111/jeu.13052","DOIUrl":"https://doi.org/10.1111/jeu.13052","url":null,"abstract":"An astonishing range of morphologies and life strategies has arisen across the vast diversity of protists, allowing them to thrive in most environments. In model protists, like Tetrahymena, Dictyostelium, or Trypanosoma, life cycles involving multiple life stages with different morphologies have been well characterized. In contrast, knowledge of the life cycles of free-living protists, which primarily consist of uncultivated environmental lineages, remains largely fragmentary. Various life stages and lineage-specific cellular innovations have been observed in the field for uncultivated protists, but such innovations generally lack functional characterization and have unknown physiological and ecological roles. In the actual state of knowledge, evidence of sexual processes is confirmed for 20% of free-living protist lineages. Nevertheless, at the onset of eukaryotic diversification, common molecular trends emerged to promote genetic recombination, establishing sex as an inherent feature of protists. Here, we review protist life cycles from the viewpoint of life cycle transitions and genetics across major eukaryotic lineages. We focus on the scarcely observed sexual cycle of free-living protists, summarizing evidence for its existence and describing key genes governing its progression, as well as, current methods for studying the genetics of sexual cycles in both cultivable and uncultivated protist groups.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":" ","pages":"e13052"},"PeriodicalIF":2.1,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141859978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Genomics and phylogenetic relationships of microsporidia and their relatives 小孢子虫及其近缘种的基因组学和系统发育关系。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-07-30 DOI: 10.1111/jeu.13051

Lilith R. South, Vedprakash G. Hurdeal, Naomi M. Fast

{"title":"Genomics and phylogenetic relationships of microsporidia and their relatives","authors":"Lilith R. South, Vedprakash G. Hurdeal, Naomi M. Fast","doi":"10.1111/jeu.13051","DOIUrl":"10.1111/jeu.13051","url":null,"abstract":"Microsporidia are intracellular parasites that all possess a unique infection apparatus involving a polar tube. Upon contact with a host cell, this tube forms the conduit through which the parasite enters the host. Infecting mostly animals, microsporidian species can be transmitted vertically or horizontally, and exert various effects on their hosts: infections range from being relatively benign to lethal. Microsporidian genomes possess highly divergent sequences and are often substantially reduced in size. Their divergent sequences and unique morphology created early challenges to our understanding of their phylogenetic position within the tree of eukaryotes. Over the last couple of decades, advances in both sequencing technology and phylogenetic methodology supported a clear relationship between microsporidia and fungi. However, the specifics of this relationship were muddied by the lack of known microsporidian relatives. With increased taxon discovery and the morphological and molecular characterization of microsporidia-like taxa, rozellids and aphelids, a better resolved picture is emerging. Here we review the history of microsporidian taxonomy and current status of genomics of microsporidia and their nearest relatives, with an aim to understand their morphological and metabolic differences, along with their evolutionary relationships.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 5","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jeu.13051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141855648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Methionine aminopeptidases: Potential therapeutic target for microsporidia and other microbes 蛋氨酸氨肽酶：微孢子虫和其他微生物的潜在治疗目标。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-07-22 DOI: 10.1111/jeu.13036

Bhaskar C. Das, Parthiban Chokkalingam, Mohammed Adil Shareef, Srushti Shukla, Sasmita Das, Mariko Saito, Louis M. Weiss

{"title":"Methionine aminopeptidases: Potential therapeutic target for microsporidia and other microbes","authors":"Bhaskar C. Das, Parthiban Chokkalingam, Mohammed Adil Shareef, Srushti Shukla, Sasmita Das, Mariko Saito, Louis M. Weiss","doi":"10.1111/jeu.13036","DOIUrl":"10.1111/jeu.13036","url":null,"abstract":"Methionine aminopeptidases (MetAPs) have emerged as a target for medicinal chemists in the quest for novel therapeutic agents for treating cancer, obesity, and other disorders. Methionine aminopeptidase is a metalloenzyme with two structurally distinct forms in humans, MetAP-1 and MetAP-2. The MetAP2 inhibitor fumagillin, which was used as an amebicide in the 1950s, has been used for the successful treatment of microsporidiosis in humans; however, it is no longer commercially available. Despite significant efforts and investments by many pharmaceutical companies, no new MetAP inhibitors have been approved for the clinic. Several lead compounds have been designed and synthesized by researchers as potential inhibitors of MetAP and evaluated for their potential activity in a wide range of diseases. MetAP inhibitors such as fumagillin, TNP-470, beloranib, and reversible inhibitors and their analogs guide new prospects for MetAP inhibitor development in the ongoing quest for new pharmacological indications. This perspective provides insights into recent advances related to MetAP, as a potential therapeutic target in drug discovery, bioactive small molecule MetAP2 inhibitors, and data on the role of MetAP-2 as a therapeutic target for microsporidiosis.","PeriodicalId":15672,"journal":{"name":"Journal of Eukaryotic Microbiology","volume":"71 5","pages":""},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141734307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Host cell manipulation by microsporidia secreted effectors: Insights into intracellular pathogenesis 微孢子虫分泌效应物对宿主细胞的操纵：洞察细胞内致病机理。

IF 2.1 4区生物学

Journal of Eukaryotic Microbiology Pub Date : 2024-07-18 DOI: 10.1111/jeu.13029

Liyuan Tang, Musa Makongoro Sabi, Ming Fu, Jingyu Guan, Yongliang Wang, Tian Xia, Kai Zheng, Hongnan Qu, Bing Han

引用次数: 0