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Liu QN, Yang TT, Wang C, Jiang SH, Zhang DZ, Tang BP, Ge BM, Wang JL, Wang D, Dai LS. A non-mammalian Toll-like receptor 26 (TLR26)gene mediates innate immune responses in yellow catfish Pelteobagrus fulvidraco. FISH & SHELLFISH IMMUNOLOGY 2019; 95:491-497. [PMID: 31689551 DOI: 10.1016/j.fsi.2019.11.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 10/24/2019] [Accepted: 11/01/2019] [Indexed: 06/10/2023]
Abstract
In this study, we identified a fish-specific Toll-like receptor (TLR) in Pelteobagrus fulvidraco, an economically important freshwater fish in China. This TLR, PfTLR26, was shown to be encoded by a 3084 bp open reading frame (ORF), producing a polypeptide 1027 amino acids in length. The PfTLR26 protein contains a signal peptide, eight leucine-rich repeat (LRR) domains, two LRR_TYP domains in the extracellular region, and a Toll/interleukin (IL)-1 receptor (TIR) domain in the cytoplasmic region, consistent with the characteristic TLR domain architecture. This predicted 117.1 kDa protein was highly homologous to those of other fish, with phylogenetic analysis revealing the closest relation to TLR26 of Ictalurus punctatus. Real-time quantitative reverse transcription-PCR (qRT-PCR) analysis showed that the PfTLR26 gene was expressed in all tissues tested, with the highest expression levels seen in the head kidney and blood, and the lowest seen in muscle. PfTLR26 exhibited significant upregulation in liver, spleen, head kidney, and blood at different time points following challenge with the common TLR agonists lipopolysaccharide (LPS) and polyriboinosinic polyribocytidylic acid (Poly I:C). Taken together, these results suggest that PfTLR26 may be an important component of the P. fulvidraco innate immune system, participating in the transduction of TLR signaling under pathogen stimulation.
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Affiliation(s)
- Qiu-Ning Liu
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China; School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, People's Republic of China; Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, People's Republic of China
| | - Ting-Ting Yang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China; Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, 200032, People's Republic of China; College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing, 210009, People's Republic of China
| | - Cheng Wang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Sen-Hao Jiang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Dai-Zhen Zhang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Bo-Ping Tang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China.
| | - Bao-Ming Ge
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Jia-Lian Wang
- Jiangsu Key Laboratory for Bioresources of Saline Soils, Jiangsu Synthetic Innovation Center for Coastal Bio-agriculture, Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, School of Ocean and Biological Engineering, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Dong Wang
- Instrumental Analysis Center, Yancheng Teachers University, Yancheng, 224007, People's Republic of China
| | - Li-Shang Dai
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325035, People's Republic of China.
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Guo CJ, He J, He JG. The immune evasion strategies of fish viruses. FISH & SHELLFISH IMMUNOLOGY 2019; 86:772-784. [PMID: 30543936 DOI: 10.1016/j.fsi.2018.12.013] [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: 09/28/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
Viral infection of a host rapidly triggers intracellular signaling events that induce interferon production and a cellular antiviral state. Viral diseases are important concerns in fish aquaculture. The major mechanisms of the fish antiviral immune response are suggested to be similar to those of mammals, although the specific details of the process require further studies. Throughout the process of pathogen-host coevolution, fish viruses have developed a battery of distinct strategies to overcome the biochemical and immunological defenses of the host. Such strategies include signaling interference, effector modulation, and manipulation of host apoptosis. This review provide an overview of the different mechanisms that fish viruses use to evade host immune responses. The basic mechanisms of immune evasion of fish virus are discussed, and some examples are provided to illustrate particular points.
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Affiliation(s)
- C J Guo
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering / State Key Laboratory for Biocontrol, School of Marine, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China; Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - J He
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering / State Key Laboratory for Biocontrol, School of Marine, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China; Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China
| | - J G He
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering / State Key Laboratory for Biocontrol, School of Marine, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China; Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-sen University, 135 Xingang Road West, Guangzhou 510275, PR China.
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3
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Lai CY, Yu GY, Luo Y, Xiang R, Chuang TH. Immunostimulatory Activities of CpG-Oligodeoxynucleotides in Teleosts: Toll-Like Receptors 9 and 21. Front Immunol 2019; 10:179. [PMID: 30800129 PMCID: PMC6375897 DOI: 10.3389/fimmu.2019.00179] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/21/2019] [Indexed: 12/31/2022] Open
Abstract
Toll-like receptors (TLRs) are pattern-recognition receptors that detect a wide variety of microbial pathogens for the initiation of host defense immunological responses. Thirteen TLRs have been identified in mammals, and teleosts contain 22 mammalian or non-mammalian TLRs. Of these, TLR9 and TLR21 are the cytosine-phosphate-guanosine-oligodeoxynucleotides (CpG-ODNs) recognition TLRs in teleosts. TLR9 is a mammalian TLR expressed in teleost but not in the avian species. TLR21 is a non-mammalian TLR expressed in both teleost and the avian species. Synthetic CpG-ODNs are potent immunostimulants that are being studied for their application against tumors, allergies, and infectious diseases, and as a vaccine adjuvant in humans. The immunostimulatory effects of CpG-ODNs as vaccine adjuvants and their antimicrobial function in domestic animals and teleosts are also being investigated. Most of our current knowledge about the molecular basis for the immunostimulatory activity of CpG-ODNs comes from earlier studies of the interaction between CpG-ODN and TLR9. More recent studies indicate that in addition to TLR9, TLR21 is another receptor for CpG-ODN recognition in teleosts to initiate immune responses. Whether these two receptors have differential functions in mediating the immunostimulatory activity of CpG-ODN in teleost has not been well-studied. Nevertheless, the existence of two recognition TLRs suggests that the molecular basis for the immunostimulatory activity of CpG-ODN in teleosts is different and more complex than in mammals. This article reviews the current knowledge of TLR9 and TLR21 activation by CpG-ODNs. The key points that need to be considered for CpG-ODNs as immunostimulants with maximum effectiveness in activation of immune responses in teleosts are discussed. This includes the structure/activity relationship of CpG-ODN activities for TLR9 and TLR21, the structure/functional relationship of these two TLRs, and differential expression levels and tissue distributions for these two TLRs.
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Affiliation(s)
- Chao-Yang Lai
- Immunology Research Center, National Health Research Institutes, Zhunan, Taiwan
| | - Guann-Yi Yu
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Zhunan, Taiwan
| | - Yunping Luo
- Deptartment of Immunology, Chinese Academy of Medical Science, School of Basic Medicine, Peking Union Medical College, Institute of Basic Medical Science, Beijing, China.,Collaborative Innovation Center for Biotherapy, School of Basic Medical Science, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Rong Xiang
- Department of Immunology, School of Medicine, Nankai University, Tianjin, China.,International Joint Center for Biomedical Research of the Ministry of Education, Tianjin, China
| | - Tsung-Hsien Chuang
- Immunology Research Center, National Health Research Institutes, Zhunan, Taiwan.,Program in Environmental and Occupational Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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Qi Z, Wang S, Zhu X, Yang Y, Han P, Zhang Q, Zhang S, Shao R, Xu Q, Wei Q. Molecular characterization of three toll-like receptors (TLR21, TLR22, and TLR25) from a primitive ray-finned fish Dabry's sturgeon (Acipenser dabryanus). FISH & SHELLFISH IMMUNOLOGY 2018; 82:200-211. [PMID: 30130656 DOI: 10.1016/j.fsi.2018.08.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 07/19/2018] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
Dabry's sturgeon (Acipenser dabryanus) is a useful model for the study of fish evolution, as it is one of the most primitive actinopterygian species. However, studies of the immune system of this fish are limited. Here, we identified three toll-like receptors (adaTLR21, adaTLR22, and adaTLR25) from Dabry's sturgeon. The three sturgeon TLRs had characteristic TLR features, including a signal peptide, several leucine rich repeat (LRR) domains, a transmembrane domain, and a Toll/interleukin-1 receptor (TIR) domain. Although the predicted amino acid sequences encoded by the sturgeon adaTLR21, adaTLR22, and adaTLR25 had somewhat low levels of sequence identity and similarity with TLRs from other fish species, the three sturgeon TLRs fell in well-supported clades with other teleost TLRs in our neighbor-joining phylogenetic tree. Real-time quantitative PCR showed that the three sturgeon TLRs were ubiquitously expressed in all examined tissues from healthy adult sturgeon, but that their expression patterns varied greatly among the different tissues. The three sturgeon TLRs were also expressed across all embryonic developmental stages that were examined, but their expression levels differed between developmental stages. All three TLRs were upregulated in head-kidney primary leucocytes following lipopolysaccharide (LPS) and polyinosinic: polycytidylic acid (polyI:C) stimulation. To the best of our knowledge, this is the first characterization of these three TLRs in Darby's sturgeon. Our results provide a framework for further studies of TLR ligand specificity and signaling pathways in sturgeon, and increase our understanding of the functional evolution of TLRs in vertebrates.
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Affiliation(s)
- Zhitao Qi
- Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China.
| | - Sisi Wang
- College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu Province, 212003, China; Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China
| | - Xiaozhen Zhu
- Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China
| | - Yuanyuan Yang
- Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China
| | - Panpan Han
- College of Animal Sciences, Yangtze University, Jingzhou, Hubei Province, 434020 China
| | - Qihuan Zhang
- Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China
| | - Shuhuan Zhang
- Key Laboratory of Freshwater Biodiversity Conservation, Ministry of Agriculture of China, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei Province, 430223, China
| | - Rong Shao
- Jiangsu Key Laboratory of Biochemistry and Biotechnology of Marine Wetland, Yancheng Institute of Technology, Yancheng, Jiangsu Province, 224051, China.
| | - Qiaoqing Xu
- College of Animal Sciences, Yangtze University, Jingzhou, Hubei Province, 434020 China
| | - Qiwei Wei
- Key Laboratory of Freshwater Biodiversity Conservation, Ministry of Agriculture of China, Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Wuhan, Hubei Province, 430223, China
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Li H, Li T, Guo Y, Li Y, Zhang Y, Teng N, Zhang F, Yang G. Molecular characterization and expression patterns of a non-mammalian toll-like receptor gene (TLR21) in larvae ontogeny of common carp (Cyprinus carpio L.) and upon immune stimulation. BMC Vet Res 2018; 14:153. [PMID: 29724212 PMCID: PMC5934810 DOI: 10.1186/s12917-018-1474-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/23/2018] [Indexed: 12/12/2022] Open
Abstract
Background In the host innate immune system, various pattern recognition receptors (PRRs) recognize conserved pathogen-associated molecular patterns (PAMPs) and represent an efficient first line of defense against invading pathogens. Toll-like receptors (TLRs) are a major class of PRRs, which are able to recognize a wide range of PAMPs and play a central role in initiating innate immune responses. TLR21 is one of the non-mammalian TLRs identified in some bird and fish species. Results In the present study, we reported the cloning and identification of a TLR21 cDNA from the head kidney of common carp (Cyprinus carpio L.), named CcTLR21. The full-length CcTLR21 cDNA was 3557 bp long, including an open reading frame (ORF) of 2895 bp, which encoded a putative protein of 964 amino acids. The putative CcTLR21 protein was found to comprise a signal peptide, 14 LRR domains in the extracellular region and a TIR domain in the cytoplasmic region, which fits with the characteristic TLR domain architecture. The phylogenetic analysis showed that CcTLR21 possessed high amino acid identities with the TLR21s in other freshwater teleosts. A Real-time PCR assay showed that CcTLR21 mRNA was expressed in almost all tissues examined in healthy common carp, while the levels obviously varied among different tissues. During the embryonic and early larval developmental stages of common carp, the CcTLR21 showed two peaks of expression, with the first at 1 dpf and the second at 10 dpf. When challenged with poly(I:C) (a viral model) or Aeromonas hydrophila, the expression level of CcTLR21 was up-regulated in a variety of common carp tissues. Conclusions Our findings indicate that CcTLR21 plays a significant role in innate immune defense during larvae ontogeny and in responses to viral or bacterial pathogens. Electronic supplementary material The online version of this article (10.1186/s12917-018-1474-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hua Li
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Ting Li
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Yujie Guo
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Yujun Li
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Yan Zhang
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Na Teng
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China
| | - Fumiao Zhang
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China.
| | - Guiwen Yang
- Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, No. 88 East Wenhua Road, Jinan, 250014, People's Republic of China.
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Li S, Wang G, Liu D, Liu Q, Hu G. Cloning and expression analysis of a Toll-like receptor 21 (TLR21) gene from turbot, Scophthalmus maximus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 73:163-168. [PMID: 28359672 DOI: 10.1016/j.dci.2017.03.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/06/2017] [Accepted: 03/06/2017] [Indexed: 06/07/2023]
Abstract
Toll-like receptor 21 (TLR21) is a non-mammalian TLR recognizing unmethylated CpG DNA and considered as a functional homolog of mammalian TLR9. In the present study, a TLR21 gene was cloned from turbot, Scophthalmus maximus, its immune responsive expression was subsequently studied in vivo. The turbot (Sm)TLR21 gene is an intronless gene with a length of 3527 bp and encodes a peptide of 984 amino acids. The deduced protein possesses a signal peptide sequence, a leucine-rich repeat (LRR) domain composed of 16 LRR motifs, a transmembrane (TM) region and a Toll/interleukin-1 receptor (TIR) domain. Phylogenetic analysis grouped it with other teleost TLR21s. Quantitative real-time PCR (qPCR) analysis demonstrated the constitutive expression of SmTLR21 mRNA in all twelve examined tissues with higher levels in the lymphomyeloid-rich tissues like spleen and head kidney. Further, upon stimulation with polyinosinic: polycytidylic acid [poly(I:C)], turbot reddish body iridovirus (TRBIV) and CpG oligodeoxynucleotides (CpG-ODN) 2395, the SmTLR21 mRNA expression was up-regulated in the gills, head kidney, spleen and muscle. The maximum increases of SmTLR21 transcript levels ranged from 1.3 to 8.1-fold and appeared at 3 h to 5 day post-injection depending on different organs and stimuli. These findings suggest that SmTLR21 may play an important role in the immune responses to the infections of a broad range of pathogens that include RNA and DNA viruses and bacteria.
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Affiliation(s)
- Song Li
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Guanjie Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Dahai Liu
- First Institute of Oceanography, State Oceanic Administration of China, Qingdao 266061, China
| | - Qiuming Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Guobin Hu
- College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; Institute of Evolution & Marine Biodiversity, Ocean University of China, Qingdao 266003, China.
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Sun M, Mu Y, Ding Y, Ao J, Chen X. Molecular and functional characterization of Toll-like receptor 21 in large yellow croaker (Larimichthys crocea). FISH & SHELLFISH IMMUNOLOGY 2016; 59:179-188. [PMID: 27751918 DOI: 10.1016/j.fsi.2016.10.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/07/2016] [Accepted: 10/13/2016] [Indexed: 06/06/2023]
Abstract
Toll-like receptor 21 (TLR21) is a non-mammalian TLR that functions similar to mammalian TLR9 in recognizing CpG DNA. In the present study, we identified a TLR21 homologue, LycTLR21, from large yellow croaker (Larimichthys crocea). The complete coding sequence of LycTLR21 is 2946 nucleotides long, encoding a protein of 981 amino acids. The deduced LycTLR21 protein has typical TLR domain architecture, including a signal peptide, 13 leucine-rich repeats (LRRs) in the extracellular region, a transmembrane region, and a cytoplasmic Toll-Interleukin-1 receptor (TIR) domain. Phylogenetic analysis showed that LycTLR21 falls into a major clade formed by all fish TLR21 sequences and is closely related to TLR21 in Epinephelus coioides and Oplegnathus fasciatus. LycTLR21 mRNA was constitutively expressed in all tissues tested, with higher levels in immune-related tissues, such as spleen, head kidney, and gills. Upon stimulation with inactivated trivalent bacterial vaccine, LycTLR21 mRNA was significantly increased in these three tissues. Overexpression of a chimeric plasmid containing the extracellular domain of human cluster of differentiation 4 (CD4) and the transmembrane and cytoplasmic domains of LycTLR21 could activate NF-κB, but not IFN-β in Chinese hamster ovary (CHO) cells, suggesting that LycTLR21 could mediate activation of NF-κB. LycTLR21 could specifically recognize three CpG-oligodeoxynucleotides (CpG-ODNs), CpG-ODN 1826, 2006, and 2007, but not other CpG-ODNs detected, poly(I:C), lipopolysaccharide (LPS), and lipoteichoic acid (LTA-SA). These three CpG-ODNs were found to significantly up-regulate the expression of LycTLR21 and downstream proinflammatory cytokines IL-1β and IL-6 of NF-κB pathway in large yellow croaker head kidney (LYCK) cells. In addition, the expression levels of LycTLR21, c-Rel subunit of NF-κB, IL-1β and IL-6 genes were quickly increased in the spleen and head kidney by bacterial infection, suggesting that LycTLR21 signaling pathway may play a role in immune response to bacterial infection.
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Affiliation(s)
- Min Sun
- School of Marine Sciences, Ningbo University, Ningbo 315211, China; Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Yinnan Mu
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Yang Ding
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Jingqun Ao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China
| | - Xinhua Chen
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361005, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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8
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Huang WJ, Yang X, Shen Y, Xu XY, Li L, Wang R, Li J. Identification and functional analysis of the toll-like receptor 20.2 gene in grass carp, Ctenopharyngodon idella. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 65:91-97. [PMID: 27370974 DOI: 10.1016/j.dci.2016.06.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/26/2016] [Accepted: 06/26/2016] [Indexed: 06/06/2023]
Abstract
We characterized and identified the cDNA sequence of Toll-like receptor 20.2 in Ctenopharyngodon idella (gctlr20.2); it consisted of 3197 bp, with an open reading frame of 2835 bp that encoded a 944 amino acid polypeptide. Relatively, high expression levels of gctlr20.2 were observed in the spleen, head kidney, liver and brain tissues, with lower expression levels in the trunk kidney, intestine and heart tissues. In vivo and in vitro, after being challenged with Aeromonas hydrophila or grass carp reovirus (GCRV), gctlr20.2 expression was induced in C. idella kidney cells stimulated with lipopolysaccharide, flagellin or polyinosinic-polycytidylic acid. Overexpression of gctlr20.2 increased the expression of il1β, il8 and tnf-α, but not ifn, and also increased the activity of the nf-κB signal pathway. Silencing, via siRNA-tlr20.2, inhibited gctlr20.2 transcription by 65.7% and down-regulated the expression of inflammatory cytokine genes, but not tnf-α. This study increases understanding of the immune system in C. idella.
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Affiliation(s)
- Wen-Ji Huang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, 201306, China
| | - Xiaomeng Yang
- Key Laboratory of Conventional Freshwater Fish Breeding and Healthy Culture Technology Ministry of Agriculture, Suzhou Shenhang Eco-Technology Development Co., LTD, Suzhou, 215221, China
| | - Yubang Shen
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, 201306, China
| | - Xiao-Yan Xu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, 201306, China
| | - Lisen Li
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, 201306, China
| | - Rongquan Wang
- Key Laboratory of Conventional Freshwater Fish Breeding and Healthy Culture Technology Ministry of Agriculture, Suzhou Shenhang Eco-Technology Development Co., LTD, Suzhou, 215221, China
| | - Jiale Li
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, 201306, China.
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Sensors of Infection: Viral Nucleic Acid PRRs in Fish. BIOLOGY 2015; 4:460-93. [PMID: 26184332 PMCID: PMC4588145 DOI: 10.3390/biology4030460] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 06/19/2015] [Accepted: 06/19/2015] [Indexed: 12/25/2022]
Abstract
Viruses produce nucleic acids during their replication, either during genomic replication or transcription. These nucleic acids are present in the cytoplasm or endosome of an infected cell, or in the extracellular space to be sensed by neighboring cells during lytic infections. Cells have mechanisms of sensing virus-generated nucleic acids; these nucleic acids act as flags to the cell, indicating an infection requiring defense mechanisms. The viral nucleic acids are called pathogen-associated molecular patterns (PAMPs) and the sensors that bind them are called pattern recognition receptors (PRRs). This review article focuses on the most recent findings regarding nucleic acids PRRs in fish, including: Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), cytoplasmic DNA sensors (CDSs) and class A scavenger receptors (SR-As). It also discusses what is currently known of the downstream signaling molecules for each PRR family and the resulting antiviral response, either type I interferons (IFNs) or pro-inflammatory cytokine production. The review highlights what is known but also defines what still requires elucidation in this economically important animal. Understanding innate immune systems to virus infections will aid in the development of better antiviral therapies and vaccines for the future.
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Elvitigala DAS, Premachandra HKA, Yeo SY, Choi CY, Whang I, Lee J. Molecular profile and expressional modulation of a Toll like receptor-1 homolog from rock bream (Oplegnathus fasciatus). Genes Genomics 2015. [DOI: 10.1007/s13258-015-0275-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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