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Emeish WFA, Fawaz MM, Hussein NM, Al-Amgad Z, Abd-ElHafeez HH, Rutland CS, Bakry KA. Characterizing Two New Henneguya Species in the Respiratory Organs of African Sharptooth Catfish. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1774-1790. [PMID: 37648416 DOI: 10.1093/micmic/ozad091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/16/2023] [Accepted: 08/06/2023] [Indexed: 09/01/2023]
Abstract
Henneguya species are myxozoans, a suborder of Cnidaria, which can affect the gills and extrarespiratory organs of the African sharptooth catfish, Clarias gariepinus. This research describes natural infection-induced histological alterations caused by the Henneguya species present. The Henneguya species were also identified molecularly using DNA sequenced from infected tissue cysts, and phylogenetically analyzed. Clinical investigations revealed cyst-like nodules on the fish gill filaments and extrarespiratory organs. Within a milky fluid inside the cysts were several Henneguya-like spores. Henneguya sp. infested 27.5% of the fish, with the highest prevalence in the gills compared to the extrarespiratory organs. The Henneguya species parasitized the gill and the dendritic tissues, resulting in histopathological characteristics. The plasmodia's developmental stages resulted in destructive damage which manifested as marked necrosis, which was replaced by a focal aggregation of inflammatory cells. Amplification of the 18S ribosomal DNA from the fish parasites was followed by sequencing, which confirmed their identities as new species Henneguya qenabranchiae n. sp. and Henneguya qenasuprabranchiae n. sp. with 99.53 and 99.64% identities, respectively, to Henneguya sp. 1 HS-2015. The two C. gariepinus myxozoans shared some characteristics based on morphologic and phylogenetic analysis as previously published, where it was proposed that they were a sister lineage to Henneguya species in Egypt, and it is now proposed that they are new species.
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Affiliation(s)
- Walaa F A Emeish
- Fish Diseases and Management, Department of Fish Diseases, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Egypt
| | - Marwa M Fawaz
- Department of Parasitology, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Egypt
| | - Nermean M Hussein
- Department of Zoology, Faculty of Science, South Valley University, Qena 83523, Egypt
| | - Zeinab Al-Amgad
- General Authority for Veterinary Services, Qena Veterinary Directorate, Qena 83511, Egypt
| | - Hanan H Abd-ElHafeez
- Department of Cell and Tissues, Faculty of Veterinary Medicine, Assiut University, Assiut 71526, Egypt
| | - Catrin Sian Rutland
- School of Veterinary Medicine and Science, University of Nottingham, Nottingham, UK
| | - Karima A Bakry
- Fish Diseases and Management, Department of Fish Diseases, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Egypt
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2
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Mechanism study of the gel-forming ability of heat-induced gel from Peruvian hake (Merluccius gayi peruanus) surimi. Food Chem 2023; 413:135635. [PMID: 36804742 DOI: 10.1016/j.foodchem.2023.135635] [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: 11/22/2022] [Revised: 01/12/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023]
Abstract
The commercial value of Peruvian hake (Merluccius gayi peruanus) meat is low because of its soft texture. This study investigated the major factor contributing to the gel-forming ability of Peruvian hake surimi by comparing the effects of endogenous protease activity and parasitic infection. Heat-induced gels could not be obtained at 50 °C-90 °C. Surimi with severe parasitic infection showed a stronger gel-forming ability. The endogenous protease activities were the main factor influencing the Peruvian hake meat proteolysis and contributed to the low gel-forming ability, rather than parasitic infection. Specifically, endogenous cysteine proteases played an essential role in protein degradation and low gel-forming ability. Moreover, endogenous transglutaminase was also shown to be involved in the gel-forming ability upon heating at 40 °C. These results suggested that Peruvian hake meat could be used as a raw material of frozen surimi for fish gel by inhibiting the activity of endogenous proteases.
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3
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Alama-Bermejo G, Bartošová-Sojková P, Atkinson SD, Holzer AS, Bartholomew JL. Proteases as Therapeutic Targets Against the Parasitic Cnidarian Ceratonova shasta: Characterization of Molecules Key to Parasite Virulence In Salmonid Hosts. Front Cell Infect Microbiol 2022; 11:804864. [PMID: 35071050 PMCID: PMC8777295 DOI: 10.3389/fcimb.2021.804864] [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: 10/29/2021] [Accepted: 11/24/2021] [Indexed: 11/13/2022] Open
Abstract
Proteases and their inhibitors play critical roles in host-parasite interactions and in the outcomes of infections. Ceratonova shasta is a myxozoan pathogen that causes enteronecrosis in economically important salmonids from the Pacific Northwest of North America. This cnidarian parasite has host-specific genotypes with varying virulence, making it a powerful system to decipher virulence mechanisms in myxozoans. Using C. shasta genome and transcriptome, we identified four proteases of different catalytic types: cathepsin D (aspartic), cathepsin L and Z-like (cysteine) and aminopeptidase-N (metallo); and a stefin (cysteine protease inhibitor), which implied involvement in virulence and hence represent target molecules for the development of therapeutic strategies. We characterized, annotated and modelled their 3D protein structure using bioinformatics and computational tools. We quantified their expression in C. shasta genotype 0 (low virulence, no mortality) and IIR (high virulence and mortality) in rainbow trout Oncorhynchus mykiss, to demonstrate that there are major differences between the genotypes during infection and parasite development. High proliferation of genotype IIR was associated with high expression of the cathepsin D and the stefin, likely correlated with high nutrient demands and to regulate cell metabolism, with upregulation preceding massive proliferation and systemic dispersion. In contrast, upregulation of the cathepsin L and Z-like cysteine proteases may have roles in host immune evasion in genotype 0 infections, which are associated with low proliferation, low inflammation and non-destructive development. In contrast to the other proteases, C. shasta aminopeptidase-N appears to have a prominent role in nematocyst formation in both genotypes, but only during sporogenesis. Homology searches of C. shasta proteases against other myxozoan transcriptomes revealed a high abundance of cathepsin L and aminopeptidase homologs suggesting common gene requirements across species. Our study identified molecules of potential therapeutic significance for aquaculture and serves as a baseline for future research aimed at functional characterisation of these targets.
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Affiliation(s)
- Gema Alama-Bermejo
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia.,Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Pavla Bartošová-Sojková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
| | - Stephen D Atkinson
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Astrid S Holzer
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czechia
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
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4
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Americus B, Hams N, Klompen AML, Alama-Bermejo G, Lotan T, Bartholomew JL, Atkinson SD. The cnidarian parasite Ceratonova shasta utilizes inherited and recruited venom-like compounds during infection. PeerJ 2022; 9:e12606. [PMID: 35003924 PMCID: PMC8684318 DOI: 10.7717/peerj.12606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/16/2021] [Indexed: 12/12/2022] Open
Abstract
Background Cnidarians are the most ancient venomous organisms. They store a cocktail of venom proteins inside unique stinging organelles called nematocysts. When a cnidarian encounters chemical and physical cues from a potential threat or prey animal, the nematocyst is triggered and fires a harpoon-like tubule to penetrate and inject venom into the prey. Nematocysts are present in all Cnidaria, including the morphologically simple Myxozoa, which are a speciose group of microscopic, spore-forming, obligate parasites of fish and invertebrates. Rather than predation or defense, myxozoans use nematocysts for adhesion to hosts, but the involvement of venom in this process is poorly understood. Recent work shows some myxozoans have a reduced repertoire of venom-like compounds (VLCs) relative to free-living cnidarians, however the function of these proteins is not known. Methods We searched for VLCs in the nematocyst proteome and a time-series infection transcriptome of Ceratonova shasta, a myxozoan parasite of salmonid fish. We used four parallel approaches to detect VLCs: BLAST and HMMER searches to preexisting cnidarian venom datasets, the machine learning tool ToxClassifier, and structural modeling of nematocyst proteomes. Sequences that scored positive by at least three methods were considered VLCs. We then mapped their time-series expressions in the fish host and analyzed their phylogenetic relatedness to sequences from other venomous animals. Results We identified eight VLCs, all of which have closely related sequences in other myxozoan datasets, suggesting a conserved venom profile across Myxozoa, and an overall reduction in venom diversity relative to free-living cnidarians. Expression of the VLCs over the 3-week fish infection varied considerably: three sequences were most expressed at one day post-exposure in the fish’s gills; whereas expression of the other five VLCs peaked at 21 days post-exposure in the intestines, coinciding with the formation of mature parasite spores with nematocysts. Expression of VLC genes early in infection, prior to the development of nematocysts, suggests venoms in C. shasta have been repurposed to facilitate parasite invasion and proliferation within the host. Molecular phylogenetics suggested some VLCs were inherited from a cnidarian ancestor, whereas others were more closely related to sequences from venomous non-Cnidarian organisms and thus may have gained qualities of venom components via convergent evolution. The presence of VLCs and their differential expression during parasite infection enrich the concept of what functions a “venom” can have and represent targets for designing therapeutics against myxozoan infections.
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Affiliation(s)
- Benjamin Americus
- Department of Microbiology, Oregon State University, Corvallis, Oregon, United States of America
| | - Nicole Hams
- Columbia River Fish and Wildlife Conservation Office, U.S. Fish and Wildlife Service, Vancouver, Washington, United States of America
| | - Anna M L Klompen
- Department of Ecology and Evolutionary Biology, The University of Kansas, Lawrence, Kansas, United States of America
| | - Gema Alama-Bermejo
- Department of Microbiology, Oregon State University, Corvallis, Oregon, United States of America.,Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Tamar Lotan
- Marine Biology Department, The Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Corvallis, Oregon, United States of America
| | - Stephen D Atkinson
- Department of Microbiology, Oregon State University, Corvallis, Oregon, United States of America
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Holzer AS, Piazzon MC, Barrett D, Bartholomew JL, Sitjà-Bobadilla A. To React or Not to React: The Dilemma of Fish Immune Systems Facing Myxozoan Infections. Front Immunol 2021; 12:734238. [PMID: 34603313 PMCID: PMC8481699 DOI: 10.3389/fimmu.2021.734238] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/01/2021] [Indexed: 11/13/2022] Open
Abstract
Myxozoans are microscopic, metazoan, obligate parasites, belonging to the phylum Cnidaria. In contrast to the free-living lifestyle of most members of this taxon, myxozoans have complex life cycles alternating between vertebrate and invertebrate hosts. Vertebrate hosts are primarily fish, although they are also reported from amphibians, reptiles, trematodes, mollusks, birds and mammals. Invertebrate hosts include annelids and bryozoans. Most myxozoans are not overtly pathogenic to fish hosts, but some are responsible for severe economic losses in fisheries and aquaculture. In both scenarios, the interaction between the parasite and the host immune system is key to explain such different outcomes of this relationship. Innate immune responses contribute to the resistance of certain fish strains and species, and the absence or low levels of some innate and regulatory factors explain the high pathogenicity of some infections. In many cases, immune evasion explains the absence of a host response and allows the parasite to proliferate covertly during the first stages of the infection. In some infections, the lack of an appropriate regulatory response results in an excessive inflammatory response, causing immunopathological consequences that are worse than inflicted by the parasite itself. This review will update the available information about the immune responses against Myxozoa, with special focus on T and B lymphocyte and immunoglobulin responses, how these immune effectors are modulated by different biotic and abiotic factors, and on the mechanisms of immune evasion targeting specific immune effectors. The current and future design of control strategies for myxozoan diseases is based on understanding this myxozoan-fish interaction, and immune-based strategies such as improvement of innate and specific factors through diets and additives, host genetic selection, passive immunization and vaccination, are starting to be considered.
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Affiliation(s)
- Astrid S Holzer
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czechia
| | - M Carla Piazzon
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal - Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
| | - Damien Barrett
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Jerri L Bartholomew
- Department of Microbiology, Oregon State University, Corvallis, OR, United States
| | - Ariadna Sitjà-Bobadilla
- Fish Pathology Group, Institute of Aquaculture Torre de la Sal - Consejo Superior de Investigaciones Científicas (IATS-CSIC), Castellón, Spain
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Survival of metazoan parasites in fish: Putting into context the protective immune responses of teleost fish. ADVANCES IN PARASITOLOGY 2021; 112:77-132. [PMID: 34024360 DOI: 10.1016/bs.apar.2021.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Defence mechanisms of fish can be divided into specific and non-specific that act in concert and are often interdependent. Most fish in both wild and cultured populations are vulnerable to metazoan parasites. Endoparasitic helminths include several species of digeneans, cestodes, nematodes, and acanthocephalans. Although they may occur in large numbers, helminth infections rarely result in fish mortality. Conversely, some ectoparasites cause mass mortality in farmed fish. Given the importance of fish innate immunity, this review addresses non-specific defence mechanisms of fish against metazoan parasites, with emphasis on granulocyte responses involving mast cells, neutrophils, macrophages, rodlet cells, and mucous cells. Metazoan parasites are important disease agents that affect wild and farmed fish and can induce high economic loss and, as pathogen organisms, deserve considerable attention. The paper will provide our light and transmission electron microscopy data on metazoan parasites-fish innate immune and neuroendocrine systems. Insights about the structure and functions of the cell types listed above and a brief account of the effects and harms of each metazoan taxon to specific fish apparati/organs will be presented.
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7
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Hartigan A, Jaimes-Becerra A, Okamura B, Doonan LB, Ward M, Marques AC, Long PF. Recruitment of toxin-like proteins with ancestral venom function supports endoparasitic lifestyles of Myxozoa. PeerJ 2021; 9:e11208. [PMID: 33981497 PMCID: PMC8083181 DOI: 10.7717/peerj.11208] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/12/2021] [Indexed: 12/12/2022] Open
Abstract
Cnidarians are the oldest lineage of venomous animals and use nematocysts to discharge toxins. Whether venom toxins have been recruited to support parasitic lifestyles in the Endocnidozoa (Myxozoa + Polypodium) is, however, unknown. To examine this issue we variously employed transcriptomic, proteomic, associated molecular phylogenies, and localisation studies on representative primitive and derived myxozoans (Malacosporea and Myxosporea, respectively), Polypodium hydriforme, and the free-living staurozoan Calvadosia cruxmelitensis. Our transcriptomics and proteomics analyses provide evidence for expression and translation of venom toxin homologs in myxozoans. Phylogenetic placement of Kunitz type serine protease inhibitors and phospholipase A2 enzymes reveals modification of toxins inherited from ancestral free-living cnidarian toxins, and that venom diversity is reduced in myxozoans concordant with their reduced genome sizes. Various phylogenetic analyses of the Kunitz-type toxin family in Endocnidozoa suggested lineage-specific gene duplications, which offers a possible mechanism for enhancing toxin diversification. Toxin localisation in the malacosporean Buddenbrockia plumatellae substantiates toxin translation and thus illustrates a repurposing of toxin function for endoparasite development and interactions with hosts, rather than for prey capture or defence. Whether myxozoan venom candidates are expressed in transmission stages (e.g. in nematocysts or secretory vesicles) requires further investigation.
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Affiliation(s)
- Ashlie Hartigan
- Department of Life Sciences, Natural History Museum, London, United Kingdom.,Faculty of Life Sciences & Medicine, King's College London, University of London, London, United Kingdom
| | - Adrian Jaimes-Becerra
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Beth Okamura
- Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Liam B Doonan
- Faculty of Life Sciences & Medicine, King's College London, University of London, London, United Kingdom
| | - Malcolm Ward
- Aulesa Biosciences Ltd, Shefford, Bedfordshire, United Kingdom
| | - Antonio C Marques
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Paul F Long
- Faculty of Life Sciences & Medicine, King's College London, University of London, London, United Kingdom.,Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
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Eszterbauer E, Szegő D, Ursu K, Sipos D, Gellért Á. Serine protease inhibitors of the whirling disease parasite Myxobolus cerebralis (Cnidaria, Myxozoa): Expression profiling and functional predictions. PLoS One 2021; 16:e0249266. [PMID: 33780500 PMCID: PMC8007001 DOI: 10.1371/journal.pone.0249266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/15/2021] [Indexed: 11/19/2022] Open
Abstract
Here, we studied the expression pattern and putative function of four, previously identified serine protease inhibitors (serpins) of Myxobolus cerebralis, a pathogenic myxozoan species (Cnidaria: Myxozoa) causing whirling disease of salmonid fishes. The relative expression profiles of serpins were determined at different developmental stages both in fish and in annelid hosts using serpin-specific qPCR assays. The expression of serpin Mc-S1 was similar throughout the life cycle, whereas a significant decrease was detected in the relative expression of Mc-S3 and Mc-S5 during the development in fish, and then in the sporogonic stage in the worm host. A decreasing tendency could also be observed in the expression of Mc-S4 in fish, which was, however, upregulated in the worm host. For the first time, we predicted the function of M. cerebralis serpins by the use of several bioinformatics-based applications. Mc-S1 is putatively a chymotrypsin-like inhibitor that locates extracellularly and is capable of heparin binding. The other three serpins are caspase-like inhibitors, and they are probably involved in protease and cell degradation processes during the early stage of fish invasion.
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Affiliation(s)
- Edit Eszterbauer
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
| | - Dóra Szegő
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
| | - Krisztina Ursu
- Veterinary Diagnostic Directorate, National Food Chain Safety Office, Budapest, Hungary
| | - Dóra Sipos
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
| | - Ákos Gellért
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary
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9
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Advances and Discoveries in Myxozoan Genomics. Trends Parasitol 2021; 37:552-568. [PMID: 33619004 DOI: 10.1016/j.pt.2021.01.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/20/2021] [Accepted: 01/23/2021] [Indexed: 12/21/2022]
Abstract
Myxozoans are highly diverse and globally distributed cnidarian endoparasites in freshwater and marine habitats. They have adopted a heteroxenous life cycle, including invertebrate and fish hosts, and have been associated with diseases in aquaculture and wild fish stocks. Despite their importance, genomic resources of myxozoans have proven difficult to obtain due to their miniaturized and derived genome character and close associations with fish tissues. The first 'omic' datasets have now become the main resource for a better understanding of host-parasite interactions, virulence, and diversity, but also the evolutionary history of myxozoans. In this review, we discuss recent genomic advances in the field and outline outstanding questions to be answered with continuous and improved efforts of generating myxozoan genomic data.
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10
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Bartošová-Sojková P, Kyslík J, Alama-Bermejo G, Hartigan A, Atkinson SD, Bartholomew JL, Picard-Sánchez A, Palenzuela O, Faber MN, Holland JW, Holzer AS. Evolutionary Analysis of Cystatins of Early-Emerging Metazoans Reveals a Novel Subtype in Parasitic Cnidarians. BIOLOGY 2021; 10:110. [PMID: 33546310 PMCID: PMC7913475 DOI: 10.3390/biology10020110] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/26/2021] [Accepted: 01/31/2021] [Indexed: 01/04/2023]
Abstract
The evolutionary aspects of cystatins are greatly underexplored in early-emerging metazoans. Thus, we surveyed the gene organization, protein architecture, and phylogeny of cystatin homologues mined from 110 genomes and the transcriptomes of 58 basal metazoan species, encompassing free-living and parasite taxa of Porifera, Placozoa, Cnidaria (including Myxozoa), and Ctenophora. We found that the cystatin gene repertoire significantly differs among phyla, with stefins present in most of the investigated lineages but with type 2 cystatins missing in several basal metazoan groups. Similar to liver and intestinal flukes, myxozoan parasites possess atypical stefins with chimeric structure that combine motifs of classical stefins and type 2 cystatins. Other early metazoan taxa regardless of lifestyle have only the classical representation of cystatins and lack multi-domain ones. Our comprehensive phylogenetic analyses revealed that stefins and type 2 cystatins clustered into taxonomically defined clades with multiple independent paralogous groups, which probably arose due to gene duplications. The stefin clade split between the subclades of classical stefins and the atypical stefins of myxozoans and flukes. Atypical stefins represent key evolutionary innovations of the two parasite groups for which their origin might have been linked with ancestral gene chimerization, obligate parasitism, life cycle complexity, genome reduction, and host immunity.
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Affiliation(s)
- Pavla Bartošová-Sojková
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; (J.K.); (G.A.-B.); (A.P.-S.); (A.S.H.)
| | - Jiří Kyslík
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; (J.K.); (G.A.-B.); (A.P.-S.); (A.S.H.)
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic
| | - Gema Alama-Bermejo
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; (J.K.); (G.A.-B.); (A.P.-S.); (A.S.H.)
| | - Ashlie Hartigan
- Department of Life Sciences, Natural History Museum, London SW7 5BD, UK;
| | - Stephen D. Atkinson
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA; (S.D.A.); (J.L.B.)
| | - Jerri L. Bartholomew
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA; (S.D.A.); (J.L.B.)
| | - Amparo Picard-Sánchez
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; (J.K.); (G.A.-B.); (A.P.-S.); (A.S.H.)
- Fish Pathology Group, Instituto de Acuicultura Torre de la Sal (IATS-CSIC), 12595 Castellón, Spain;
| | - Oswaldo Palenzuela
- Fish Pathology Group, Instituto de Acuicultura Torre de la Sal (IATS-CSIC), 12595 Castellón, Spain;
| | - Marc Nicolas Faber
- Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK; (M.N.F.); (J.W.H.)
| | - Jason W. Holland
- Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK; (M.N.F.); (J.W.H.)
| | - Astrid S. Holzer
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice, Czech Republic; (J.K.); (G.A.-B.); (A.P.-S.); (A.S.H.)
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