1
|
Zhao L, He K, Jiang C, Wang G, Hu S, Wang T, Qian W, Wei Z, Xiong J, Miao W, Yan W. Comparative Genomic and Transcriptomic Profiling Revealed the Molecular Basis of Starch Promoting the Growth and Proliferation of Balantioides coli. Animals (Basel) 2023; 13:ani13101608. [PMID: 37238038 DOI: 10.3390/ani13101608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/07/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
Carbohydrates are the main source of nutrition for B. coli, supplying energy for cell growth and development. The research aimed at investigating the mechanism of starch on the growth and replication of B. coli. Single-cell separation was used to isolate single trophozoites of B. coli under a stereomicroscope, transcriptomic profiling was conducted based on the SMART-seq2 single-cell RNA-seq method. Comparative genomic analysis was performed on B. coli and eight other ciliates to obtain specific and expanded gene families of B. coli. GO and KEGG enrichment analysis were used to analyze the key genes of B. coli under the action of starch in the present study. The results of single-cell RNA-seq depicts starch affected the growth and replication of B. coli in two ways: (1) the cell cycle was positively promoted by the activation of the cAMP/PKA signaling pathway via glycolysis; (2) the cell autophagy was suppressed through the PI3K/AKT/mTOR pathway. Genes involved in endocytosis, carbohydrate utilization, and the cAMP/PKA signaling pathway were highly enriched in both specific and expanded gene families of B. coli. Starch can be ingested and hydrolyzed into glucose, in turn affecting various biological processes of B. coli. The molecular mechanism of the effect of starch on the growth and proliferation of B. coli by promoting cell cycle and inhibiting the autophagy of trophozoites has been elucidated in our study.
Collapse
Affiliation(s)
- Lizhuo Zhao
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| | - Kai He
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
- National Animal Protozoa Laboratory, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Chuanqi Jiang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Guangying Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Suhui Hu
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| | - Tianqi Wang
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| | - Weifeng Qian
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| | - Zhiguo Wei
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| | - Jie Xiong
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wenchao Yan
- Parasitology Laboratory, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471023, China
| |
Collapse
|
2
|
Yang J, Wang Z, Wang C, Tang D, Zang Z, Stover NA, Chen X, Li L. Single-cell transcriptome reveals cell division-regulated hub genes in the unicellular eukaryote Paramecium. Eur J Protistol 2023; 89:125978. [PMID: 37080141 DOI: 10.1016/j.ejop.2023.125978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/20/2023] [Accepted: 04/03/2023] [Indexed: 04/22/2023]
Abstract
The transition from growth to division during the cell cycle encompasses numerous conserved processes such as large-scale DNA replication and protein synthesis. In ciliate cells, asexual cell division is accompanied by additional cellular changes including amitotic nuclear division, extensive ciliogenesis, and trichocyst replication. However, the molecular mechanisms underlying these processes remain elusive. In this study, we present single-cell gene expression profiles of Paramecium cf. multimicronucleatum cells undergoing cell division. Our results reveal that the most up-regulated genes in dividing cells compared to growing cells are associated with 1) cell cycle signaling pathways including transcription, DNA replication, chromosome segregation and protein degradation; 2) microtubule proteins and tubulin glycylases which are essential for ciliogenesis, nuclei separation and structural differentiation signaling; and 3) trichocyst matrix proteins involved in trichocyst synthesis and reproduction. Furthermore, weighted gene co-expression network analysis identified hub genes that may play crucial roles during cell division. Our findings provide insights into cell cycle regulators, microtubules and trichocyst matrix proteins that may exert influence on this process in ciliates.
Collapse
Affiliation(s)
- Juan Yang
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China
| | - Zhenyuan Wang
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China
| | - Chundi Wang
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China
| | - Danxu Tang
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China
| | - Zihan Zang
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China
| | - Naomi A Stover
- Department of Biology, Bradley University, Peoria 61625, USA
| | - Xiao Chen
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China; Suzhou Research Institute, Shandong University, Suzhou 215123, China.
| | - Lifang Li
- Laboratory of Marine Protozoan Biodiversity & Evolution, Marine College, Shandong University, Weihai 264209, China.
| |
Collapse
|
3
|
Jiang C, Wang G, Zhang J, Gu S, Wang X, Qin W, Chen K, Yuan D, Chai X, Yang M, Zhou F, Xiong J, Miao W. iGDP: An integrated genome decontamination pipeline for wild ciliated microeukaryotes. Mol Ecol Resour 2023. [PMID: 36912756 DOI: 10.1111/1755-0998.13782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 02/25/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023]
Abstract
Ciliates are a large group of ubiquitous and highly diverse single-celled eukaryotes that play an essential role in the functioning of microbial food webs. However, their genomic diversity is far from clear due to the need to develop cultivation methods for most species, so most research is based on wild organisms that almost invariably contain contaminants. Here we establish an integrated Genome Decontamination Pipeline (iGDP) that combines homology search, telomere reads-assisted and clustering approaches to filter contaminated ciliate genome assemblies from wild specimens. We benchmarked the performance of iGDP using genomic data from a contaminated ciliate culture and the results showed that iGDP could recall 91.9% of the target sequences with 96.9% precision. We also used a synthetic dataset to offer guidelines for the application of iGDP in the removal of various groups of contaminants. Compared with several popular metagenome binning tools, iGDP could show better performance. To further validate the effectiveness of iGDP on real-world data, we applied it to decontaminate genome assemblies of three wild ciliate specimens and obtained their genomes with high quality comparable to that of previously well-studied model ciliate genomes. It is anticipated that the newly generated genomes and the established iGDP method will be valuable community resources for detailed studies on ciliate biodiversity, phylogeny, ecology and evolution. The pipeline (https://github.com/GWang2022/iGDP) can be implemented automatically to reduce manual filtering and classification and may be further developed to apply to other microeukaryotes.
Collapse
Affiliation(s)
- Chuanqi Jiang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Guangying Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jing Zhang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Siyu Gu
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xueyan Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Weiwei Qin
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Kai Chen
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Dongxia Yuan
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xiaocui Chai
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Mingkun Yang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Fang Zhou
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jie Xiong
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Freshwater Ecology and Biotechnology, Wuhan, China
- CAS Center for Excellence in Animal Evolution and Genetics, Kunming, China
| |
Collapse
|
4
|
Lyu L, Asghar U, Fu J, Gao Y, Zhang X, Al-Farraj SA, Chen Z, Gao F. Comparative analysis of single-cell genome sequencing techniques toward the characterization of germline and somatic genomes in ciliated protists. Eur J Protistol 2023; 88:125969. [PMID: 36822126 DOI: 10.1016/j.ejop.2023.125969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 01/31/2023] [Accepted: 02/05/2023] [Indexed: 02/12/2023]
Abstract
Ciliated protists contain both germline micronucleus (MIC) and somatic macronucleus (MAC) in a single cytoplasm. Programmed genome rearrangements occur in ciliates during sexual processes, and the extent of rearrangements varies dramatically among species, which lead to significant differences in genomic architectures. However, genomic sequences remain largely unknown for most ciliates due to the difficulty in culturing and in separating the germline from the somatic genome in a single cell. Single-cell whole genome amplification (WGA) has emerged as a powerful technology to characterize the genomic heterogeneity at the single-cell level. In this study, we compared two single-cell WGA, multiple displacement amplification (MDA) and multiple annealing and looping-based amplification cycles (MALBAC) in characterizing the germline and somatic genomes in ciliates with different genomic architectures. Our results showed that: 1) MALBAC exhibits strong amplification bias towards MAC genome while MDA shows bias towards MIC genome of ciliates with extensively fragmented MAC genome; 2) both MDA and MALBAC could amplify MAC genome more efficiently in ciliates with moderately fragmented MAC genome. Moreover, we found that more sample replicates could help to obtain more genomic data. Our work provides a reference for selecting the appropriate method to characterize germline and somatic genomes of ciliates.
Collapse
Affiliation(s)
- Liping Lyu
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China
| | - Usman Asghar
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China
| | - Jinyu Fu
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China
| | - Yunyi Gao
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China
| | - Xue Zhang
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China
| | - Saleh A Al-Farraj
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Zigui Chen
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
| | - Feng Gao
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Key Laboratory of Mariculture (OUC), Ministry of Education, Qingdao 266003, China; Laoshan Laboratory, Qingdao 266237, China.
| |
Collapse
|
5
|
Zhou Y, Fu L, Mochizuki K, Xiong J, Miao W, Wang G. Absolute quantification of chromosome copy numbers in the polyploid macronucleus of Tetrahymena thermophila at the single-cell level. J Eukaryot Microbiol 2022; 69:e12907. [PMID: 35313044 DOI: 10.1111/jeu.12907] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amitosis is widespread among eukaryotes, but the underlying mechanisms are poorly understood. The polyploid macronucleus (MAC) of unicellular ciliates divides by amitosis, making ciliates a potentially valuable model system to study this process. However, a method to accurately quantify the copy number of MAC chromosomes has not yet been established. Here we used droplet digital PCR (ddPCR) to quantify the absolute copy number of the MAC chromosomes in Tetrahymena thermophila. We first confirmed that ddPCR is a sensitive and reproducible method to determine accurate chromosome copy numbers at the single-cell level. We then used ddPCR to determine the copy number of different MAC chromosomes by analyzing individual T. thermophila cells in the G1 and the amitotic (AM) phases. The average copy number of MAC chromosomes was 90.9 at G1 phase, approximately half the number at AM phase (189.8). The copy number of each MAC chromosome varied among individual cells in G1 phase and correlated with cell size, suggesting that amitosis accompanied by unequal cytokinesis causes copy number variability. Furthermore, the fact that MAC chromosome copy number is less variable among AM-phase cells suggests that the copy number is standardized by regulating DNA replication. We also demonstrated that copy numbers differ among different MAC chromosomes and that interchromosomal variations in copy number are consistent across individual cells. Our findings demonstrate that ddPCR can be used to model amitosis in T. thermophila and possibly in other ciliates.
Collapse
Affiliation(s)
- Yuanyuan Zhou
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lu Fu
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Kazufumi Mochizuki
- Institute of Human Genetics (IGH), CNRS, University of Montpellier, Montpellier, 34090, France
| | - Jie Xiong
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.,University of Chinese Academy of Sciences, Beijing, 100049, China.,State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.,CAS Center for Excellence in Animal Evolution and Genetics, Kunming, 650223, China
| | - Guangying Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| |
Collapse
|
6
|
Wang G, Fu L, Xiong J, Mochizuki K, Fu Y, Miao W. Identification and Characterization of Base-Substitution Mutations in the Macronuclear Genome of the Ciliate Tetrahymena thermophila. Genome Biol Evol 2021; 13:evaa232. [PMID: 33146387 PMCID: PMC7788487 DOI: 10.1093/gbe/evaa232] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2020] [Indexed: 02/06/2023] Open
Abstract
Polyploidy can provide adaptive advantages and drive evolution. Amitotic division of the polyploid macronucleus (MAC) in ciliates acts as a nonsexual genetic mechanism to enhance adaptation to stress conditions and thus provides a unique model to investigate the evolutionary role of polyploidy. Mutation is the primary source of the variation responsible for evolution and adaptation; however, to date, de novo mutations that occur in ciliate MAC genomes during these processes have not been characterized and their biological impacts are undefined. Here, we carried out long-term evolution experiments to directly explore de novo MAC mutations and their molecular features in the model ciliate, Tetrahymena thermophila. A simple but effective method was established to detect base-substitution mutations in evolving populations whereas filtering out most of the false positive base-substitutions caused by repetitive sequences and the programmed genome rearrangements. The detected mutations were rigorously validated using the MassARRAY system. Validated mutations showed a strong G/C→A/T bias, consistent with observations in other species. Moreover, a progressive increase in growth rate of the evolving populations suggested that some of these mutations might be responsible for cell fitness. The established mutation identification and validation methods will be an invaluable resource to make ciliates an important model system to study the role of polyploidy in evolution.
Collapse
Affiliation(s)
- Guangying Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Lu Fu
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jie Xiong
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Kazufumi Mochizuki
- Institute of Human Genetics (IGH), CNRS, University of Montpellier, France
| | - Yunxin Fu
- Department of Biostatistics and Data Science and Human Genetics Center, School of Public Health, The University of Texas Health Science Center
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- CAS Center for Excellence in Animal Evolution and Genetics, Kunming, China
| |
Collapse
|
7
|
Wang G, Chen K, Zhang J, Deng S, Xiong J, He X, Fu Y, Miao W. Drivers of Mating Type Composition in Tetrahymena thermophila. Genome Biol Evol 2020; 12:2328-2343. [PMID: 32946549 PMCID: PMC7846192 DOI: 10.1093/gbe/evaa197] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2020] [Indexed: 11/23/2022] Open
Abstract
Sex offers advantages even in primarily asexual species. Some ciliates appear to utilize such reproductive strategy with many mating types. However, the factors determining the composition of mating types in the unicellular ciliate Tetrahymena thermophila are poorly understood, and this is further complicated by non-Mendelian determination of mating type in the offspring. We therefore developed a novel population genetics model to predict how various factors influence the dynamics of mating type composition, including natural selection. The model predicted either the coexistence of all seven mating types or fixation of a single mating type in a population, depending on parameter combinations, irrespective of natural selection. To understand what factor(s) may be more influential and to test the validity of theoretical prediction, five replicate populations were maintained in laboratory such that several factors could be controlled or measured. Whole-genome sequencing was used to identify newly arising mutations and determine mating type composition. Strikingly, all populations were found to be driven by strong selection on newly arising beneficial mutations to fixation of their carrying mating types, and the trajectories of speed to fixation agreed well with our theoretical predictions. This study illustrates the evolutionary strategies that T. thermophila can utilize to optimize population fitness.
Collapse
Affiliation(s)
- Guangying Wang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Kai Chen
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jing Zhang
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Shanjun Deng
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Jie Xiong
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
| | - Xionglei He
- State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China
| | - Yunxin Fu
- Laboratory for Conservation and Utilization of Bioresources, Yunnan University, Kunming, China.,Department of Biostatistics and Data Science and Human Genetics Center, School of Public Health, The University of Texas Health Science Center, Houston
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China.,University of Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Animal Evolution and Genetics, Kunming, China
| |
Collapse
|
8
|
Bacteria-Derived Hemolysis-Related Genes Widely Exist in Scuticociliates. Microorganisms 2020; 8:microorganisms8111838. [PMID: 33266460 PMCID: PMC7709021 DOI: 10.3390/microorganisms8111838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 11/30/2022] Open
Abstract
Scuticociliatosis is an invasive external or systemic infection caused by ciliated protozoa, mainly those within the subclass Scuticociliatia (scuticociliates). Many scuticociliates are fish pathogens, including Miamiensis avidus, Philasterides dicentrarchi, Pseudocohnilembus persalinus, and Uronema marinum. Our previous study showed that hemolysis-related genes derived from bacteria through horizontal gene transfer (HGT) may contribute to virulence in P. persalinus. Hemorrhagic lesions are a common feature of scuticociliatosis, but it is not known whether other scuticociliates also have bacteria-derived hemolysis-related genes. In this study, we constructed a high-quality macronuclear genome of another typical pathogenic scuticociliate, U. marinum. A total of 105 HGT genes were identified in this species, of which 35 were homologs of hemolysis-related genes (including hemolysin-like genes) that had previously been identified in P. persalinus. Sequencing of an additional five species from four scuticociliate families showed that bacteria-derived hemolysis-related genes (especially hemolysin-like genes) are widely distributed in scuticociliates. Based on these findings, we suggest that hemolysin-like genes may have originated before the divergence of scuticociliates.
Collapse
|