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Kyslík J, Born-Torrijos A, Holzer AS, Kosakyan A. RNAi-directed knockdown in the cnidarian fish blood parasite Sphaerospora molnari. Sci Rep 2024; 14:3545. [PMID: 38347054 PMCID: PMC10861503 DOI: 10.1038/s41598-024-54171-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 02/09/2024] [Indexed: 02/15/2024] Open
Abstract
RNA interference (RNAi) is an effective approach to suppress gene expression and monitor gene regulation. Despite its wide application, its use is limited in certain taxonomic groups, including cnidarians. Myxozoans are a unique group of cnidarian parasites that diverged from their free-living ancestors about 600 million years ago, with several species causing acute disease in farmed and wild fish populations. In this pioneering study we successfully applied RNAi in blood stages of the myxozoan Sphaerospora molnari, combining a dsRNA soaking approach, real-time PCR, confocal microscopy, and Western blotting. For proof of concept, we knocked down two unusual actins, one of which is known to play a critical role in S. molnari cell motility. We observed intracellular uptake of dsRNA after 30 min and accumulation in all cells of the typical myxozoan cell-in-cell structure. We successfully knocked down actin in S. molnari in vitro, with transient inhibition for 48 h. We observed the disruption of the cytoskeletal network within the primary cell and loss of the characteristic rotational cell motility. This RNAi workflow could significantly advance functional research within the Myxozoa, offering new prospects for investigating therapeutic targets and facilitating drug discovery against economically important fish parasites.
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Affiliation(s)
- Jiří Kyslík
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, Ceske Budejovice, Czech Republic.
| | - Ana Born-Torrijos
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, Ceske Budejovice, Czech Republic
- Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, Den Burg, PO Box 59, 1790 AB, Texel, The Netherlands
| | - Astrid S Holzer
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, Ceske Budejovice, Czech Republic
- Fish Health Division, University of Veterinary Medicine, Vienna, Austria
| | - Anush Kosakyan
- Institute of Parasitology, Biology Centre, Academy of Sciences of the Czech Republic, Ceske Budejovice, Czech Republic
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- National Biodiversity Future Center (NBFC), Palermo, Italy
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Akram N, El-Matbouli M, Saleh M. The Immune Response to the Myxozoan Parasite Myxobolus cerebralis in Salmonids: A Review on Whirling Disease. Int J Mol Sci 2023; 24:17392. [PMID: 38139218 PMCID: PMC10743445 DOI: 10.3390/ijms242417392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/03/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
Salmonids are affected by the economically significant whirling disease (WD) caused by the myxozoan parasite Myxobolus cerebralis. In the past, it was endemic to Eurasia, but it has now spread to different regions of North America, Europe, New Zealand, and South Africa. Among salmonids, rainbow trout is considered the most highly susceptible host. Upon entering to the host's body, the parasite invades the spine and cranium, resulting in whirling behaviour, a blackened tail, and destruction of cartilage. The disease is characterized by the infiltration of numerous inflammatory cells, primarily lymphocytes and macrophages, with the onset of fibrous tissue infiltration. Several efforts have been undertaken to investigate the role of various immune modulatory molecules and immune regulatory genes using advanced molecular methods including flow cytometry and transcriptional techniques. Investigation of the molecular and cellular responses, the role of STAT3 in Th17 cell differentiation, and the inhibitory actions of suppressors of cytokine signaling (SOCS) on interferons and interleukins, as well as the role of natural resistance-associated macrophage proteins (Nramp) in WD have significantly contributed to our understanding of the immune regulation mechanism in salmonids against M. cerebralis. This review thoroughly highlights previous research and discusses potential future directions for understanding the molecular immune response of salmonids and the possible development of prophylactic approaches against WD.
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Affiliation(s)
| | | | - Mona Saleh
- Division of Fish Health, Department of Farm Animals and Veterinary Public Health, University of Veterinary Medicine, 1210 Vienna, Austria; (N.A.)
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Gutási A, Hammer SE, El-Matbouli M, Saleh M. Review: Recent Applications of Gene Editing in Fish Species and Aquatic Medicine. Animals (Basel) 2023; 13:ani13071250. [PMID: 37048506 PMCID: PMC10093118 DOI: 10.3390/ani13071250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 04/08/2023] Open
Abstract
Gene editing and gene silencing techniques have the potential to revolutionize our knowledge of biology and diseases of fish and other aquatic animals. By using such techniques, it is feasible to change the phenotype and modify cells, tissues and organs of animals in order to cure abnormalities and dysfunctions in the organisms. Gene editing is currently experimental in wide fields of aquaculture, including growth, controlled reproduction, sterility and disease resistance. Zink finger nucleases, TALENs and CRISPR/Cas9 targeted cleavage of the DNA induce favorable changes to site-specific locations. Moreover, gene silencing can be used to inhibit the translation of RNA, namely, to regulate gene expression. This methodology is widely used by researchers to investigate genes involved in different disorders. It is a promising tool in biotechnology and in medicine for investigating gene function and diseases. The production of food fish has increased markedly, making fish and seafood globally more popular. Consequently, the incidence of associated problems and disease outbreaks has also increased. A greater investment in new technologies is therefore needed to overcome such problems in this industry. To put it concisely, the modification of genomic DNA and gene silencing can comprehensively influence aquatic animal medicine in the future. On the ethical side, these precise genetic modifications make it more complicated to recognize genetically modified organisms in nature and can cause several side effects through created mutations. The aim of this review is to summarize the current state of applications of gene modifications and genome editing in fish medicine.
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Affiliation(s)
- Anikó Gutási
- Department of Farm Animals and Veterinary Public Health, Division of Fish Health, University of Veterinary Medicine, 1210 Vienna, Austria
| | - Sabine E. Hammer
- Department of Pathobiology, Institute of Immunology, University of Veterinary Medicine, 1210 Vienna, Austria
| | - Mansour El-Matbouli
- Department of Farm Animals and Veterinary Public Health, Division of Fish Health, University of Veterinary Medicine, 1210 Vienna, Austria
| | - Mona Saleh
- Department of Farm Animals and Veterinary Public Health, Division of Fish Health, University of Veterinary Medicine, 1210 Vienna, Austria
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Saleh M, Abdel-Baki AAS, Dkhil MA, El-Matbouli M, Al-Quraishy S. Silencing of heat shock protein 90 (hsp90): Effect on development and infectivity of Ichthyophthirius multifiliis. BMC Vet Res 2023; 19:62. [PMID: 36932404 PMCID: PMC10024447 DOI: 10.1186/s12917-023-03613-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 02/23/2023] [Indexed: 03/19/2023] Open
Abstract
BACKGROUND Recently, an increasing number of ichthyophthiriasis outbreaks has been reported, leading to high economic losses in fisheries and aquaculture. Although several strategies, including chemotherapeutics and immunoprophylaxis, have been implemented to control the parasite, no effective method is available. Hence, it is crucial to discover novel drug targets and vaccine candidates against Ichthyophthirius multifiliis. For this reason, understanding the parasite stage biology, host-pathogen interactions, molecular factors, regulation of major aspects during the invasion, and signaling pathways of the parasite can promote further prospects for disease management. Unfortunately, functional studies have been hampered in this ciliate due to the lack of robust methods for efficient nucleic acid delivery and genetic manipulation. In the current study, we used antisense technology to investigate the effects of targeted gene knockdown on the development and infectivity of I. multifiliis. Antisense oligonucleotides (ASOs) and their gold nanoconjugates were used to silence the heat shock protein 90 (hsp90) of I. multifiliis. Parasite stages were monitored for motility and development. In addition, the ability of the treated parasites to infect fish and cause disease was evaluated. RESULTS We demonstrated that ASOs were rapidly internalized by I. multifiliis and distributed diffusely throughout the cytosol. Knocking down of I. multifiliis hsp90 dramatically limited the growth and development of the parasite. In vivo exposure of common carp (Cyprinus carpio) showed reduced infectivity of ASO-treated theronts compared with the control group. No mortalities were recorded in the fish groups exposed to theronts pre-treated with ASOs compared with the 100% mortality observed in the non-treated control fish. CONCLUSION This study presents a gene regulation approach for investigating gene function in I. multifiliis in vitro. In addition, we provide genetic evidence for the crucial role of hsp90 in the growth and development of the parasite, suggesting hsp90 as a novel therapeutic target for successful disease management. Further, this study introduces a useful tool and provides a significant contribution to the assessing and understanding of gene function in I. multifiliis.
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Affiliation(s)
- Mona Saleh
- Clinical Division of Fish Medicine, University of Veterinary Medicine, Veterinärplatz 1, Vienna, 1210, Austria.
| | | | - Mohamed A Dkhil
- Department of Zoology and Entomology, Faculty of Science, Helwan University, Cairo, Egypt
| | - Mansour El-Matbouli
- Clinical Division of Fish Medicine, University of Veterinary Medicine, Veterinärplatz 1, Vienna, 1210, Austria
- Scchool of Biotechnology, Badr University in Cairo (BUC), Badr City, Cairo, Egypt
| | - Saleh Al-Quraishy
- Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia
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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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Selection of suitable reference genes for gene expression studies in myxosporean (Myxozoa, Cnidaria) parasites. Sci Rep 2019; 9:15073. [PMID: 31636316 PMCID: PMC6803631 DOI: 10.1038/s41598-019-51479-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 10/02/2019] [Indexed: 12/25/2022] Open
Abstract
Myxozoans (Cnidaria: Myxozoa) are an extremely diversified group of endoparasites some of which are causative agents of serious diseases in fish. New methods involving gene expression studies have emerged over the last years to better understand and control myxozoan diseases. Quantitative RT-PCR is the most extensively used approach for gene expression studies. However, the accuracy of the results depends on the normalization of the data to reference genes. We studied the expression of eight commonly used reference genes, adenosylhomocysteinase (AHC1), beta actin (ACTB), eukaryotic translation elongation factor 2 (EF2), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), hypoxanthine-guanine phosphoribosyltransferase 1 (HPRT1), DNA-directed RNA polymerase II (RPB2), 18S ribosomal RNA (18S), 28S ribosomal RNA (28S) across different developmental stages of three myxozoan species, Sphaerospora molnari, Myxobolus cerebralis and Ceratonova shasta, representing the three major myxozoan linages from the largest class Myxosporea. The stable reference genes were identified using four algorithms: geNorm, NormFinder, Bestkeeper and ΔCq method. Additionally, we analyzed transcriptomic data from S. molnari proliferative and spore-forming stages to compare the relative amount of expressed transcripts with the most stable reference genes suggested by RT-qPCR. Our results revealed that GAPDH and EF2 are the most uniformly expressed genes across the different developmental stages of the studied myxozoan species.
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Madureira TV, Pinheiro I, Malhão F, Castro LFC, Rocha E, Urbatzka R. Silencing of PPARαBb mRNA in brown trout primary hepatocytes: effects on molecular and morphological targets under the influence of an estrogen and a PPARα agonist. Comp Biochem Physiol B Biochem Mol Biol 2018; 229:1-9. [PMID: 30528668 DOI: 10.1016/j.cbpb.2018.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 12/01/2018] [Indexed: 12/23/2022]
Abstract
The crosstalk between peroxisome proliferator-activated receptor α (PPARα) and estrogenic pathways are shared from fish to humans. Salmonid fish had an additional genome duplication, and two PPARα isoforms (PPARαBa and PPARαBb) were previously identified. Since a negative regulation between estrogen signaling and PPARα was described, a post-transcriptional gene silencing for PPARαBb was designed in primary brown trout hepatocytes. The aims of the study were to: (i) decipher the effects of PPARαBb knock-down on peroxisome morphology and on mRNA expression of potential target genes, and (ii) to assess the cross-interferences caused by an estrogenic compound (17α-ethinylestradiol - EE2) and a PPARα agonist (Wy-14,643 - Wy) using the established knock-down model. A knock-down efficiency of 70% was achieved for PPARαBb and its silencing significantly reduced the volume density of peroxisomes, but did not alter mRNA levels of the studied genes. Exposure to Wy did not change peroxisome morphology or mRNA expression, but under silencing conditions Wy rescued the volume density of peroxisomes to control levels, and increased acyl-coenzyme A oxidase 1-3l (Acox1-3l) mRNA. Exposure to EE2 caused a reduction of peroxisome volume density, but under silencing conditions this effect was abolished and ApoA1 mRNA level was diminished. The morphological alterations of peroxisomes by WY and EE2 demonstrated that obtained results are PPARαBb dependent, and suggest the regulation of unknown downstream targets of PPARαBb. In summary, PPARαBb is involved in the control of peroxisome size and/or number, which opens future opportunities to explore its regulation and molecular targets.
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Affiliation(s)
- Tânia Vieira Madureira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Department of Microscopy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - Ivone Pinheiro
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Department of Microscopy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - Fernanda Malhão
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Department of Microscopy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - L Filipe C Castro
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Department of Biology, University of Porto (U.Porto), Rua do Campo Alegre, P 4169-007 Porto, Portugal
| | - Eduardo Rocha
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal; Department of Microscopy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto (U.Porto), Laboratory of Histology and Embryology, Rua Jorge Viterbo Ferreira 228, P 4050-313 Porto, Portugal
| | - Ralph Urbatzka
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto (U.Porto), Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208 Matosinhos, Portugal.
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Sipos D, Ursu K, Dán Á, Herczeg D, Eszterbauer E. Susceptibility-related differences in the quantity of developmental stages of Myxobolus spp. (Myxozoa) in fish blood. PLoS One 2018; 13:e0204437. [PMID: 30240456 PMCID: PMC6150660 DOI: 10.1371/journal.pone.0204437] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 09/09/2018] [Indexed: 01/19/2023] Open
Abstract
Here, we investigated the early development of two closely related myxozoan parasites, the highly pathogenic Myxobolus cerebralis, the causative agent of the whirling disease in salmonids, and Myxobolus pseudodispar, a common, non-pathogenic parasite of cyprinids. The aim of our study was to examine under in vivo laboratory conditions whether fish blood is involved in the intrapiscine development of the two parasite species and investigate if there is dissimilarity between the parasite infection intensity in blood and if it varies in terms of host susceptibility and parasite pathogenicity. Highly susceptible, less susceptible and non-susceptible hosts were involved. Blood samples were taken 1 day, 1 week and 1 month post exposure to M. cerebralis and M. pseudodispar, respectively. The prevalence and infection intensity was estimated by parasite-specific quantitative real-time PCR. Although previous findings assumed that M. cerebralis might escape from host immune system by migrating via peripheral nerves, our experimental results demonstrated that M. cerebralis is present in blood during the early stage of intrapiscine development. For the non-pathogenic M. pseudodispar, the highest infection prevalence was found in the original host, common roach Rutilus rutilus, whereas the highest infection intensity was detected in rudd Scardinius erythrophthalmus, a “dead-end” host of the parasite. The presence of M. pseudodispar developmental stages in the blood of both susceptible and non-susceptible cyprinids suggests that the susceptibility differences remain hidden during the early stage of infection. Our findings supply further evidence that host specificity is not determined during the early, intrapiscine development involving the vascular system. Furthermore, we found remarkable differences in the infection dynamics of the two parasite species examined, possibly due to their distinct pathogenicity or variations in adaptive capabilities to immune components in host blood.
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Affiliation(s)
- Dóra Sipos
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Krisztina Ursu
- Veterinary Diagnostic Directorate, National Food Chain Safety Office (NFCSO), Budapest, Hungary
| | - Ádám Dán
- Veterinary Diagnostic Directorate, National Food Chain Safety Office (NFCSO), Budapest, Hungary
| | - Dávid Herczeg
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
| | - Edit Eszterbauer
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary
- * E-mail:
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Gotesman M, Menanteau-Ledouble S, Saleh M, Bergmann SM, El-Matbouli M. A new age in AquaMedicine: unconventional approach in studying aquatic diseases. BMC Vet Res 2018; 14:178. [PMID: 29879957 PMCID: PMC5992843 DOI: 10.1186/s12917-018-1501-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 05/24/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Marine and aquaculture industries are important sectors of the food production and global trade. Unfortunately, the fish food industry is challenged with a plethora of infectious pathogens. The freshwater and marine fish communities are rapidly incorporating novel and most up to date techniques for detection, characterization and treatment strategies. Rapid detection of infectious diseases is important in preventing large disease outbreaks. MAIN TEXT One hundred forty-six articles including reviews papers were analyzed and their conclusions evaluated in the present paper. This allowed us to describe the most recent development research regarding the control of diseases in the aquatic environment as well as promising avenues that may result in beneficial developments. For the characterization of diseases, traditional sequencing and histological based methods have been augmented with transcriptional and proteomic studies. Recent studies have demonstrated that transcriptional based approaches using qPCR are often synergistic to expression based studies that rely on proteomic-based techniques to better understand pathogen-host interactions. Preventative therapies that rely on prophylactics such as vaccination with protein antigens or attenuated viruses are not always feasible and therefore, the development of therapies based on small nucleotide based medicine is on the horizon. Of those, RNAi or CRISPR/Cas- based therapies show great promise in combating various types of diseases caused by viral and parasitic agents that effect aquatic and fish medicine. CONCLUSIONS In our modern times, when the marine industry has become so vital for feed and economic stability, even the most extreme alternative treatment strategies such as the use of small molecules or even the use of disease to control invasive species populations should be considered.
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Affiliation(s)
- Michael Gotesman
- Department of Biology, New York City College of Technology of the City University of New York, Brooklyn, New York, USA
| | - Simon Menanteau-Ledouble
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria
| | - Mona Saleh
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria
| | - Sven M Bergmann
- Institute of Infectology, Friedrich-Loffler-Institut (FLI), Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
| | - Mansour El-Matbouli
- Clinical Division of Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria.
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