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Yang XD, Hou ZS, Liu MQ, Zeng C, Zhao HK, Xin YR, Xiang KW, Yang Q, Wen HS, Li JF. Identification and characterization of mkk genes and their expression profiles in rainbow trout (Oncorhynchus mykiss) symptomatically or asymptomatically infected with Vibrio anguillarum. FISH & SHELLFISH IMMUNOLOGY 2022; 121:1-11. [PMID: 34974153 DOI: 10.1016/j.fsi.2021.12.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/25/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Mitogen-activated protein kinase kinases (MKKs) are intermediate kinases of mitogen-activated protein kinases (MAPKs) signaling pathways. MKKs are activated by mitogen-activated protein kinase kinase kinase (MKKK) and then the activated MKKs trigger the activation of downstream MAPKs. MAPK signaling pathways play an important role in regulating immune functions including apoptosis and inflammation. However, studies on identification and characterization of mkk repertoire in rainbow trout (Oncorhynchus mykiss) are still limited. Trout experienced 4 rounds (4R) of whole genome duplication (WGD), thus exhibiting increased paralogs of mkks with potentially functional diversity. In this study, we identified 17 mkk genes in trout and the following bacterial challenge (Vibrio anguillarum) studies showed functional diversity of different mkk subtypes. Vibrio anguillarum infection resulted in significantly up-regulated mkk2 subtypes in spleen and liver, and mkk4b3 in spleen, suggesting immunomodulation was regulated by activation of ERK, p38 and JNK pathways. Compared to other mkk subtypes, mkk6s were down-regulated in symptomatic group, rather than asymptomatic group. The organisms present negative feedback on MAPK activation, thus reducing extra damage to cells. We observed down-regulated mkk6s with up-regulated genes (dusp1 & dusp2) involved in negative feedback of MAPK activation. Based on these results, we might propose the distinct expression patterns of genes associated with MAPK pathways resulted in different phenotypes and symptoms of trout in response to bacterial challenge.
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Affiliation(s)
- Xiao-Dong Yang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Zhi-Shuai Hou
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Meng-Qun Liu
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Chu Zeng
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Hong-Kui Zhao
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Yuan-Ru Xin
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Kai-Wen Xiang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Qian Yang
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Hai-Shen Wen
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China.
| | - Ji-Fang Li
- Key Laboratory of Mariculture (Ocean University of China), Ministry of Education (KLMME), Ocean University of China, Qingdao, China.
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Sun Y, Xu W, Li D, Zhou H, Qu F, Cao S, Tang J, Zhou Y, He Z, Li H, Zhou Z, Liu Z. p38 mitogen-activated protein kinases (MAPKs) are involved in intestinal immune response to bacterial muramyl dipeptide challenge in Ctenopharyngodon idella. Mol Immunol 2020; 118:79-90. [DOI: 10.1016/j.molimm.2019.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 01/11/2023]
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Su YL, Chen JP, Mo ZQ, Zheng JY, Lv SY, Li PH, Wei YS, Liang YL, Wang SW, Yang M, Dan XM, Huang XH, Huang YH, Qin QW, Sun HY. A novel MKK gene (EcMKK6) in Epinephelus coioides: Identification, characterization and its response to Vibrio alginolyticus and SGIV infection. FISH & SHELLFISH IMMUNOLOGY 2019; 92:500-507. [PMID: 31247318 DOI: 10.1016/j.fsi.2019.06.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 05/31/2019] [Accepted: 06/23/2019] [Indexed: 06/09/2023]
Abstract
Mitogen-activated protein kinase 6 (MKK6) is one of the major important central regulatory proteins response to environmental and physiological stimuli. In this study, a novel MKK6, EcMKK6, was isolated from Epinephelus coioides, an economically important cultured fish in China and Southeast Asian counties. The open reading frame (ORF) of EcMKK6 is 1077 bp encoding 358 amino acids. EcMKK6 contains a serine/threonine protein kinase (S_TKc) domain, a tyrosine kinase catalytic domain, a conserved dual phosphorylation site in the SVAKT motif and a conserved DVD domain. By in situ hybridization (ISH) with Digoxigenin-labeled probe, EcMKK6 mainly located at the cytoplasm of cells, and a little appears in the nucleus. EcMKK6 mRNA can be detected in all eleven tissues examined, but the expression level is different in these tissues. After challenge with Vibrio alginolyticus and Singapore grouper iridovirus (SGIV), the transcription level of EcMKK6 was apparently up-regulated in the tissues examined. The data demonstrated that the sequence and the characters of EcMKK6 were conserved, EcMKK6 showed tissue-specific expression profiles in healthy grouper, and the expression was significantly varied after pathogen infection, indicating that EcMKK6 may play important roles in E. coioides during pathogen-caused inflammation.
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Affiliation(s)
- Yu-Ling Su
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Jin-Peng Chen
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Ze-Quan Mo
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Jia-Ying Zheng
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Shun-You Lv
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Pin-Hong Li
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Yu-Si Wei
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Yu-Lin Liang
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Shao-Wen Wang
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Min Yang
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Xue-Ming Dan
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Xiao-Hong Huang
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - You-Hua Huang
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China
| | - Qi-Wei Qin
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China.
| | - Hong-Yan Sun
- Joint Laboratory of Guangdong Province and Hong Kong Regions on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, Guangdong Province, PR China.
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Qu F, Tang J, Liao J, Chen B, Song P, Luo W, Xiong D, Liu T, Gao Q, Lu S, Liu Z. Mitogen-activated protein kinase kinase 6 is involved in the immune response to bacterial di-/tripeptide challenge in grass carp Ctenopharyngodon idella. FISH & SHELLFISH IMMUNOLOGY 2019; 84:795-801. [PMID: 30393177 DOI: 10.1016/j.fsi.2018.10.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/19/2018] [Accepted: 10/26/2018] [Indexed: 06/08/2023]
Abstract
Mitogen-activated protein kinase kinase 6 (MKK6) is an essential component of the p38MAPK signaling pathway, which is involved in the modulation of inflammation, cell apoptosis and survival responses in mammals. However, the function of MKK6s in teleosts is still unclear. In this study, a fish MKK6 homolog (CiMKK6) was first identified from the grass carp (Ctenopharyngodon idella), a freshwater fish. CiMKK6 cDNA encodes a putative protein of 357 amino acids that contains conserved structural characteristics of the MKK6 family, including the S_TKc domain, SVAKT motif and DVD site. The deduced CiMKK6 protein exhibits high sequence homology with other reported fish MKK6s and shares the closest relationship with MKK6 from Danio rerio. Quantitative real-time PCR (qRT-PCR) analysis revealed that CiMKK6 mRNA was widely expressed in all tested tissues and stages of embryonic development. Additionally, the transcript levels of CiMKK6 in the intestine were significantly upregulated in response to bacterial muramyl dipeptide (MDP) and L-Ala-γ-D-Glu-meso-diaminopimelic acid (Tri-DAP) stimulation. Moreover, subcellular localization analysis indicated that CiMKK6 was distributed in both the cytoplasm and the nucleus of HEK293T cells. Finally, overexpression of CiMKK6 significantly enhanced the transcriptional activity of the AP-1 reporter gene in HEK293T cells. Overall, these findings may help better clarify the immune function of teleost MKK6s and provide new insight into the immune defense mechanisms of grass carp.
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Affiliation(s)
- Fufa Qu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China; State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, 410081, China
| | - Jianzhou Tang
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Jinting Liao
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Bei Chen
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Peng Song
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Wenjie Luo
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China; State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, 410081, China
| | - Ding Xiong
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Tianting Liu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Qianting Gao
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Shuangqing Lu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China
| | - Zhen Liu
- Hunan Provincial Key Laboratory of Nutrition and Quality Control of Aquatic Animals, Department of Biological and Environmental Engineering, Changsha University, Changsha, 410022, China; State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, 410081, China.
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Iliev DB, Hansen T, Jørgensen SM, Krasnov A, Jørgensen JB. CpG- and LPS-activated MAPK signaling in in vitro cultured salmon (Salmo salar) mononuclear phagocytes. FISH & SHELLFISH IMMUNOLOGY 2013; 35:1079-1085. [PMID: 23872471 DOI: 10.1016/j.fsi.2013.07.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/25/2013] [Accepted: 07/09/2013] [Indexed: 06/02/2023]
Abstract
The Mitogen-activated protein kinases (MAPK) are involved in transmitting intracellular signals downstream of diverse cell surface receptors and mediate the response to ligands such as growth factors, hormones and cytokines. In addition, MAPK are critically involved in the innate immune response to pathogen-derived substances, commonly referred to as pathogen-associated molecular patterns (PAMPs), such as bacterial lipopolysaccharide (LPS) and bacterial DNA rich in CpG dinucleotides. Currently, a great deal of knowledge is available about the involvement of MAPK in the innate immune response to PAMPs in mammals; however, little is known about the role of the different MAPK classes in the immune response to PAMPs in lower vertebrates. In the current study, p38 phosphorylation was induced by CpG oligonucleotides (ODNs) and LPS in primary salmon mononuclear phagocytes. Pre-treatment of the cells with a p38 inhibitor (SB203580) blocked the PAMP-induced p38 activity and suppressed the upregulation of most of the CpG- and LPS-induced transcripts highlighting the role of this kinase in the salmon innate immune response to PAMPs. In contrast to p38, the phosphorylation of extracellular signal-regulated kinase (ERK), a MAPK involved primarily in response to mitogens, was high in resting cells and, surprisingly, incubation with both CpG and control ODNs downregulated the phospho-ERK levels independently of p38 activation. The basal phospho-ERK level and the CpG-inducible p38 phosphorylation were greatly influenced by the length of in vitro incubation. The basal phospho-ERK level increased gradually throughout a 5-day culture period and was PI3K-dependent as demonstrated by its sensitivity to Wortmannin suggesting it is influenced by growth factors. Overall these data indicate that both basal and PAMP-induced activity of MAPKs might be greatly influenced by the differentiation status of salmon mononuclear phagocytes.
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Affiliation(s)
- Dimitar B Iliev
- The Norwegian College of Fishery Science, University of Tromsø, N-9037 Tromsø, Norway
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Rothweiler U, Åberg E, Johnson KA, Hansen TE, Jørgensen JB, Engh RA. p38α MAP kinase dimers with swapped activation segments and a novel catalytic loop conformation. J Mol Biol 2011; 411:474-85. [PMID: 21699901 DOI: 10.1016/j.jmb.2011.06.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2011] [Revised: 06/06/2011] [Accepted: 06/08/2011] [Indexed: 01/08/2023]
Abstract
Many protein kinase functions, including autophosphorylation in trans, require dimerization, possibly by activation segment exchange. Such dimers have been reported for a few autophosphorylating protein kinases, but not for mitogen-activated protein kinases (MAPKs). Activation of MAPKs proceeds not only via the well-characterized action of dual T/Y specificity MAPK kinases, phosphorylating both residues of the MAPK TxY activation loop motif, but also via a noncanonical activation pathway triggered by phosphorylation at Tyr323 and homodimerization. Here, we report the 2. 7-Å-resolution structure of p38α MAPK from Salmo salar in a novel domain-swapped homodimeric form. The tyrosines of the conserved sequence YxAPE anchor the swapped activation segments in a configuration suitable for autophosphorylation in trans and provide a model for the noncanonical pathway. In the dimer, a structural unit containing Tyr323 is formed at a dimerization contact region that stabilizes the HRD catalytic loop in a unique inactive geometry. This feature is consistent with the requirement of Tyr323 phosphorylation for the initiation of the noncanonical pathway. Despite the interacting surface of more than 2600 Å(2), the dimer is not obligate, as gel filtration shows the dimerization to occur only at relatively high concentrations. The transition from monomer to dimer involves a relatively simple hinged displacement of helix EF and adjacent residues. Thus, dimer formation is likely to be transient, compatible with functional requirements for autophosphorylation, allowing further modulation, for example, by scaffolding mechanisms.
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Affiliation(s)
- Ulli Rothweiler
- Department of Chemistry, The Norwegian Structural Biology Centre, University of Tromsø, 9037 Tromsø, Norway
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Skjesol A, Hansen T, Shi CY, Thim HL, Jørgensen JB. Structural and functional studies of STAT1 from Atlantic salmon (Salmo salar). BMC Immunol 2010; 11:17. [PMID: 20353564 PMCID: PMC2855521 DOI: 10.1186/1471-2172-11-17] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Accepted: 03/30/2010] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Type I and type II interferons (IFNs) exert their effects mainly through the JAK/STAT pathway, which is presently best described in mammals. STAT1 is involved in signaling pathways induced by both types of IFNs. It has a domain-like structure including an amino-terminus that stabilizes interaction between STAT dimers in a promoter-binding situation, a coiled coil domain facilitating interactions to other proteins, a central DNA-binding domain, a SH2 domain responsible for dimerization of phosphorylated STATs and conserved phosphorylation sites within the carboxy terminus. The latter is also the transcriptional activation domain. RESULTS A salmon (Salmo salar) STAT1 homologue, named ssSTAT1a, has been identified and was shown to be ubiquitously expressed in various cells and tissues. The ssSTAT1a had a domain-like structure with functional motifs that are similar to higher vertebrates. Endogenous STAT1 was shown to be phosphorylated at tyrosine residues both in salmon leukocytes and in TO cells treated with recombinant type I and type II IFNs. Also ectopically expressed ssSTAT1 was phosphorylated in salmon cells upon in vitro stimulation by the IFNs, confirming that the cloned gene was recognized by upstream tyrosine kinases. Treatment with IFNs led to nuclear translocation of STAT1 within one hour. The ability of salmon STAT1 to dimerize was also shown. CONCLUSIONS The structural and functional properties of salmon STAT1 resemble the properties of mammalian STAT1.
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Affiliation(s)
- Astrid Skjesol
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, University of Tromsø N- 9037 Tromsø, Norway
| | - Tom Hansen
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, University of Tromsø N- 9037 Tromsø, Norway
| | - Cheng-Yin Shi
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, University of Tromsø N- 9037 Tromsø, Norway
- Current address: Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, PR China
| | - Hanna L Thim
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, University of Tromsø N- 9037 Tromsø, Norway
| | - Jorunn B Jørgensen
- Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, University of Tromsø N- 9037 Tromsø, Norway
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Skjesol A, Aamo T, Hegseth MN, Robertsen B, Jørgensen JB. The interplay between infectious pancreatic necrosis virus (IPNV) and the IFN system: IFN signaling is inhibited by IPNV infection. Virus Res 2009; 143:53-60. [PMID: 19463721 PMCID: PMC7114382 DOI: 10.1016/j.virusres.2009.03.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 03/05/2009] [Accepted: 03/05/2009] [Indexed: 12/24/2022]
Abstract
Infectious pancreatic necrosis virus (IPNV) is a major pathogen in the aquaculture industry worldwide. Factors contributing to IPNV pathogenicity are yet poorly understood. Indications of IPNV being able to evade or counteract innate host defense come from its lack of ability to induce strong type I interferon (IFN) responses in cell culture. We show here that addition of salmon rIFN-α1 to cells prior to IPNV infection halts the viral protein synthesis and prevents processing of pVP2 into mature VP2. Furthermore, compared to pre-treatment with IFN-α1 the antiviral state in cells infected with IPNV prior to IFN-treatment, was antagonized by IPNV, as detected by higher viral titers, faster viral protein synthesis and also by reduced Mx expression. The longer headstart the virus gets, the more prominent is the weakening of IFN signaling. IPNV VP4 and VP5 inhibit IFN-induced expression from the Mx promoter, indicating that these proteins contribute to the antagonistic effect.
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