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Lee FFY, Harris C, Alper S. RNA Binding Proteins that Mediate LPS-induced Alternative Splicing of the MyD88 Innate Immune Regulator. J Mol Biol 2024; 436:168497. [PMID: 38369277 PMCID: PMC11001520 DOI: 10.1016/j.jmb.2024.168497] [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: 12/10/2023] [Revised: 02/08/2024] [Accepted: 02/14/2024] [Indexed: 02/20/2024]
Abstract
Inflammation driven by Toll-like receptor (TLR) signaling pathways is required to combat infection. However, inflammation can damage host tissues; thus it is essential that TLR signaling ultimately is terminated to prevent chronic inflammatory disorders. One mechanism that terminates persistent TLR signaling is alternative splicing of the MyD88 signaling adaptor, which functions in multiple TLR signaling pathways. While the canonical long isoform of MyD88 (MyD88-L) mediates TLR signaling and promotes inflammation, an alternatively-spliced shorter isoform of MyD88 (MyD88-S) produces a dominant negative inhibitor of TLR signaling. MyD88-S production is induced by inflammatory agonists including lipopolysaccharide (LPS), and thus MyD88-S induction is thought to act as a negative feedback loop that prevents chronic inflammation. Despite the potential role that MyD88-S production plays in inflammatory disorders, the mechanisms controlling MyD88 alternative splicing remain unclear. Here, we identify two RNA binding proteins, SRSF1 and HNRNPU, that regulate LPS-induced alternative splicing of MyD88.
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Affiliation(s)
- Frank Fang Yao Lee
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO 80206, USA; Center for Genes, Environment and Health, National Jewish Health, Denver, CO 80206, USA; Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz, CO 80045, USA
| | - Chelsea Harris
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO 80206, USA; Center for Genes, Environment and Health, National Jewish Health, Denver, CO 80206, USA; Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz, CO 80045, USA
| | - Scott Alper
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO 80206, USA; Center for Genes, Environment and Health, National Jewish Health, Denver, CO 80206, USA; Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz, CO 80045, USA.
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2
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Xiong LM, Zhang L, Long Z, Zhao X, Ying YR, Xiao TY, Xiong ST. TBK1 upregulates the interferon response against virus by the TBK1-IRF3/7 axis in yellow catfish (Pelteobagrus fulvidraco). FISH & SHELLFISH IMMUNOLOGY 2024; 144:109272. [PMID: 38061442 DOI: 10.1016/j.fsi.2023.109272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 11/29/2023] [Accepted: 12/04/2023] [Indexed: 12/31/2023]
Abstract
Yellow catfish (Pelteobagrus fulvidraco) is an important economic species of freshwater fish, widely distributed in China. Recently, viral diseases of yellow catfish have been identified in Chian (Hubei province), arising more attention to the viral immunity in P. fulvidraco. Tumor necrosis factor (TNF) receptor-associated factor NF-κB activator (TANK)-binding kinase 1 (TBK1) plays an essential role in IFN production and innate antiviral immunity. In the present study, we characterized the P. fulvidraco TBK1 (PfTBK1) and reported its function in interferon response. The full-length open reading frame (ORF) is 2184 bp encoding a protein with 727 amino acids, which is composed of four conserved domains, including KD, ULD, CCD1, and CCD2, similar to TBK1 in other species. Pftbk1 was widely expressed in all detected tissues by qPCR and was not inducible by the spring viremia of carp virus (SVCV), a single-strand RNA virus. In addition, the cellular distribution indicated that PfTBK1 was only located in the cytoplasm. Moreover, PfTBK1 induced strong IFN promoter activities through the Jak-stat pathway, and PfTBK1 interacted with and significantly phosphorylated IFN regulatory factor 3/7 (IRF3/7) in P. fulvidraco, promoting the nuclear translocation of pfIRF3 and PfIRF7, and PfTBK1 upregulated IFN response by PfTBK1-PfIRF3/7 axis. Above all, PfTBK1 triggered IFN response and strongly inhibited the replication of SVCV in EPC cells through induction of IFN downstream IFN-stimulated genes (ISGs). Summarily, this work reveals that PfTBK1 plays a positive regulatory role in IFN induction through the TBK1-IRF3/7 axis, laying a foundation for further exploring the molecular mechanism of the antiviral process in P. fulvidraco.
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Affiliation(s)
- Li-Ming Xiong
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Lei Zhang
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Zhe Long
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Xiang Zhao
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; Yuelushan Lab, Changsha, 410128, China
| | - Yan-Rong Ying
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China
| | - Tiao-Yi Xiao
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; Yuelushan Lab, Changsha, 410128, China
| | - Shu-Ting Xiong
- Fisheries College, Hunan Agricultural University, Changsha, 410128, China; Hunan Engineering Technology Research Center of Featured Aquatic Resources Utilization, Hunan Agricultural University, Changsha, 410128, China; Yuelushan Lab, Changsha, 410128, China.
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3
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Zheng Q, Gao F, Liu Z, Sun C, Dong J, Zhang H, Ke X, Lu M. Nile tilapia TBK1 interacts with STING and TRAF3 and is involved in the IFN-β pathway in the immune response. FISH & SHELLFISH IMMUNOLOGY 2023; 142:109125. [PMID: 37805113 DOI: 10.1016/j.fsi.2023.109125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/09/2023]
Abstract
Nile tilapia (Oreochromis niloticus) occupies an important position in the culture of economic fish in China. However, the high mortality caused by streptococcal disease has had a significant impact on the tilapia farming industry. Therefore, it is necessary to clarify the immune mechanism of tilapia in response to Streptococcus agalactiae. As a hub in the natural immune signaling pathway, the junction molecule can help the organism defend against and clear pathogens and is crucial in the signaling pathway. In this study, the cDNA sequence of Nile tilapia TBK1 was cloned, and the expression profile was examined in normal fish and challenged fish. The cDNA sequence of the TBK1 gene was 3378 bp, and its open reading frame (ORF) was 2172 bp, encoding 723 amino acids. The deduced TBK1 protein contained an S_TKc domain, a coiled coil domain and a ubiquitin-like domain (ULD). TBK1 had the highest homology with zebra mbuna (Maylandia zebra) and Lake Malawi cichlid fish (Astatotilapia calliptera), both at 97.59%. In the phylogenetic tree, TBK1 forms a large branch with other scleractinian fish. TBK1 expression was highest in the brain and lowest in the liver. LPS, Poly I:C, and S. agalactiae challenge resulted in significant changes in TBK1 expression in the tissues examined. The subcellular localization showed that TBK1-GFP was distributed in the cytoplasm and could significantly increase IFN-β activation. Pull-down results showed that there was an interaction between TBK1 and TRAF3 and an interaction between STING protein and TBK1 protein. The above results provide a basis for further investigation into the mechanism of TBK1 involvement in the signaling pathway.
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Affiliation(s)
- Qiuyue Zheng
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China; College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China
| | - Fengying Gao
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China.
| | - Zhigang Liu
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
| | - Chengfei Sun
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
| | - Junjian Dong
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
| | - Hetong Zhang
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
| | - Xiaoli Ke
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
| | - Maixin Lu
- Pearl River Fisheries Research Institute/Key Laboratory of Tropical & Subtropical Fishery Resource Application & Cultivation, Ministry of Agriculture, Chinese Academy of Fishery Science, Guangzhou, 510380, China
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Su CF, Das D, Muhammad Aslam M, Xie JQ, Li XY, Chen MX. Eukaryotic splicing machinery in the plant-virus battleground. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1793. [PMID: 37198737 DOI: 10.1002/wrna.1793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 02/24/2023] [Accepted: 04/19/2023] [Indexed: 05/19/2023]
Abstract
Plant virual infections are mainly caused by plant-virus parasitism which affects ecological communities. Some viruses are highly pathogen specific that can infect only specific plants, while some can cause widespread harm, such as tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). After a virus infects the host, undergoes a series of harmful effects, including the destruction of host cell membrane receptors, changes in cell membrane components, cell fusion, and the production of neoantigens on the cell surface. Therefore, competition between the host and the virus arises. The virus starts gaining control of critical cellular functions of the host cells and ultimately affects the fate of the targeted host plants. Among these critical cellular processes, alternative splicing (AS) is an essential posttranscriptional regulation process in RNA maturation, which amplify host protein diversity and manipulates transcript abundance in response to plant pathogens. AS is widespread in nearly all human genes and critical in regulating animal-virus interactions. In particular, an animal virus can hijack the host splicing machinery to re-organize its compartments for propagation. Changes in AS are known to cause human disease, and various AS events have been reported to regulate tissue specificity, development, tumour proliferation, and multi-functionality. However, the mechanisms underlying plant-virus interactions are poorly understood. Here, we summarize the current understanding of how viruses interact with their plant hosts compared with humans, analyze currently used and putative candidate agrochemicals to treat plant-viral infections, and finally discussed the potential research hotspots in the future. This article is categorized under: RNA Processing > Splicing Mechanisms RNA Processing > Splicing Regulation/Alternative Splicing.
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Affiliation(s)
- Chang-Feng Su
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, Guizhou Province, China
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for Research and Development of Fine Chemicals, Guizhou University, Guiyang, China
| | - Debatosh Das
- College of Agriculture, Food and Natural Resources (CAFNR), Division of Plant Sciences & Technology, University of Missouri, Columbia, Missouri, USA
| | - Mehtab Muhammad Aslam
- College of Agriculture, Food and Natural Resources (CAFNR), Division of Plant Sciences & Technology, University of Missouri, Columbia, Missouri, USA
- Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Ji-Qin Xie
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, Guizhou Province, China
| | - Xiang-Yang Li
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, Guizhou Province, China
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for Research and Development of Fine Chemicals, Guizhou University, Guiyang, China
| | - Mo-Xian Chen
- Key laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang, Guizhou Province, China
- National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for Research and Development of Fine Chemicals, Guizhou University, Guiyang, China
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5
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Li R, Gao S, Chen H, Zhang X, Yang X, Zhao J, Wang Z. Virus usurps alternative splicing to clear the decks for infection. Virol J 2023; 20:131. [PMID: 37340420 DOI: 10.1186/s12985-023-02098-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 06/12/2023] [Indexed: 06/22/2023] Open
Abstract
Since invasion, there will be a tug-of-war between host and virus to scramble cellular resources, for either restraining or facilitating infection. Alternative splicing (AS) is a conserved and critical mechanism of processing pre-mRNA into mRNAs to increase protein diversity in eukaryotes. Notably, this kind of post-transcriptional regulatory mechanism has gained appreciation since it is widely involved in virus infection. Here, we highlight the important roles of AS in regulating viral protein expression and how virus in turn hijacks AS to antagonize host immune response. This review will widen the understandings of host-virus interactions, be meaningful to innovatively elucidate viral pathogenesis, and provide novel targets for developing antiviral drugs in the future.
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Affiliation(s)
- Ruixue Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Shenyan Gao
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Huayuan Chen
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Xiaozhan Zhang
- College of Veterinary Medicine, Henan University of Animal Husbandry and Economy, Zhengzhou, People's Republic of China
| | - Xia Yang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Jun Zhao
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China
| | - Zeng Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, People's Republic of China.
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6
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Sehrawat S, Garcia-Blanco MA. RNA virus infections and their effect on host alternative splicing. Antiviral Res 2023; 210:105503. [PMID: 36572191 PMCID: PMC9852092 DOI: 10.1016/j.antiviral.2022.105503] [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: 11/28/2022] [Revised: 12/15/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
It is evident that viral infection dramatically alters host gene expression, and these alterations have both pro- and anti-viral functions. While the effects of viral infection on transcription and translation have been comprehensively reviewed, less attention has been paid to the impact on alternative splicing of pre-messenger RNAs. Here we review salient examples of how viral infection leads to changes in alternative splicing and discuss how these changes impact infection.
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Affiliation(s)
- Sapna Sehrawat
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77550, USA.
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77550, USA; Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77550, USA; Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77550, USA.
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7
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Mann JT, Riley BA, Baker SF. All differential on the splicing front: Host alternative splicing alters the landscape of virus-host conflict. Semin Cell Dev Biol 2023; 146:40-56. [PMID: 36737258 DOI: 10.1016/j.semcdb.2023.01.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/24/2023] [Accepted: 01/25/2023] [Indexed: 02/05/2023]
Abstract
Alternative RNA splicing is a co-transcriptional process that richly increases proteome diversity, and is dynamically regulated based on cell species, lineage, and activation state. Virus infection in vertebrate hosts results in rapid host transcriptome-wide changes, and regulation of alternative splicing can direct a combinatorial effect on the host transcriptome. There has been a recent increase in genome-wide studies evaluating host alternative splicing during viral infection, which integrates well with prior knowledge on viral interactions with host splicing proteins. A critical challenge remains in linking how these individual events direct global changes, and whether alternative splicing is an overall favorable pathway for fending off or supporting viral infection. Here, we introduce the process of alternative splicing, discuss how to analyze splice regulation, and detail studies on genome-wide and splice factor changes during viral infection. We seek to highlight where the field can focus on moving forward, and how incorporation of a virus-host co-evolutionary perspective can benefit this burgeoning subject.
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Affiliation(s)
- Joshua T Mann
- Infectious Disease Program, Lovelace Biomedical Research Institute, Albuquerque, NM, USA
| | - Brent A Riley
- Infectious Disease Program, Lovelace Biomedical Research Institute, Albuquerque, NM, USA
| | - Steven F Baker
- Infectious Disease Program, Lovelace Biomedical Research Institute, Albuquerque, NM, USA.
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8
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Zhang J, Chang MX. TBK1 Isoform Inhibits Grass Carp Reovirus Infection by Targeting the Degradation of Viral Nonstructural Proteins NS80 and NS38. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:191-203. [PMID: 36445692 DOI: 10.4049/jimmunol.2200471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 11/03/2022] [Indexed: 01/03/2023]
Abstract
TANK-binding kinase 1 (TBK1) undergoes alternative splicing, and the previously reported TBK1 isoforms are negative regulators of RIG-I-like receptor-mediated type I IFN production. Although a study has suggested that grass carp TBK1 has an opposite effect at high- and low-titer of grass carp reovirus (GCRV) infection, the functions of grass carp TBK1 isoforms in GCRV infection remain unclear. In this study, we show that a TBK1 isoform from grass carp (Ctenopharyngodon idellus) named as gcTBK1_tv3, which has a 1-aa difference with zebrafish TBK1_tv3, inhibits the replication and infection of GCRV both at high and low titers of infection in C. idellus kidney cells. gcTBK1_tv3 can colocalize and interact with the NS80 and NS38 proteins of GCRV. Furthermore, gcTBK1_tv3 specifically degrades the NS80 and NS38 proteins of GCRV through the ubiquitin-proteasome pathway. Mechanistically, gcTBK1_tv3 promotes the degradation of NS80 or NS38 for K48-linked ubiquitination by targeting the Lys503 residue of NS80 or Lys328 residue of NS38, respectively, which ultimately impairs the production of cytoplasmic viral inclusion bodies and limits GCRV replication and infection. Taken together, our findings provide insight into the function of TBK1 isoform in the antiviral immune response and demonstrate that TBK1 isoform can target the nonstructural proteins of GCRV for impairing the formation of viral inclusion bodies.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China; and.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Wuhan, China
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9
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Lee FFY, Alper S. Alternative pre-mRNA splicing as a mechanism for terminating Toll-like Receptor signaling. Front Immunol 2022; 13:1023567. [PMID: 36531997 PMCID: PMC9755862 DOI: 10.3389/fimmu.2022.1023567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
While inflammation induced by Toll-like receptor (TLR) signaling is required to combat infection, persistent inflammation can damage host tissues and contribute to a myriad of acute and chronic inflammatory disorders. Thus, it is essential not only that TLR signaling be activated in the presence of pathogens but that TLR signaling is ultimately terminated. One mechanism that limits persistent TLR signaling is alternative pre-mRNA splicing. In addition to encoding the canonical mRNAs that produce proteins that promote inflammation, many genes in the TLR signaling pathway also encode alternative mRNAs that produce proteins that are dominant negative inhibitors of signaling. Many of these negative regulators are induced by immune challenge, so production of these alternative isoforms represents a negative feedback loop that limits persistent inflammation. While these alternative splicing events have been investigated on a gene by gene basis, there has been limited systemic analysis of this mechanism that terminates TLR signaling. Here we review what is known about the production of negatively acting alternative isoforms in the TLR signaling pathway including how these inhibitors function, how they are produced, and what role they may play in inflammatory disease.
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Affiliation(s)
- Frank Fang Yao Lee
- Department of Immunology and Genomic Medicine and Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States,Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz, CO, United States
| | - Scott Alper
- Department of Immunology and Genomic Medicine and Center for Genes, Environment, and Health, National Jewish Health, Denver, CO, United States,Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz, CO, United States,*Correspondence: Scott Alper,
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10
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Wang C, Chen L, Chen Y, Jia W, Cai X, Liu Y, Ji F, Xiong P, Liang A, Liu R, Guan Y, Cheng Z, Weng Y, Wang W, Duan Y, Kuang D, Xu S, Cai H, Xia Q, Yang D, Wang MW, Yang X, Zhang J, Cheng C, Liu L, Liu Z, Liang R, Wang G, Li Z, Xia H, Xia T. Abnormal global alternative RNA splicing in COVID-19 patients. PLoS Genet 2022; 18:e1010137. [PMID: 35421082 PMCID: PMC9089920 DOI: 10.1371/journal.pgen.1010137] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Revised: 05/10/2022] [Accepted: 03/08/2022] [Indexed: 12/25/2022] Open
Abstract
Viral infections can alter host transcriptomes by manipulating host splicing machinery. Despite intensive transcriptomic studies on SARS-CoV-2, a systematic analysis of alternative splicing (AS) in severe COVID-19 patients remains largely elusive. Here we integrated proteomic and transcriptomic sequencing data to study AS changes in COVID-19 patients. We discovered that RNA splicing is among the major down-regulated proteomic signatures in COVID-19 patients. The transcriptome analysis showed that SARS-CoV-2 infection induces widespread dysregulation of transcript usage and expression, affecting blood coagulation, neutrophil activation, and cytokine production. Notably, CD74 and LRRFIP1 had increased skipping of an exon in COVID-19 patients that disrupts a functional domain, which correlated with reduced antiviral immunity. Furthermore, the dysregulation of transcripts was strongly correlated with clinical severity of COVID-19, and splice-variants may contribute to unexpected therapeutic activity. In summary, our data highlight that a better understanding of the AS landscape may aid in COVID-19 diagnosis and therapy.
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Affiliation(s)
- Changli Wang
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lijun Chen
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yaobin Chen
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Wenwen Jia
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xunhui Cai
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Yufeng Liu
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Fenghu Ji
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Peng Xiong
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Anyi Liang
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Ren Liu
- Department of Research and Development, Hugobiotech Co. Ltd., Beijing, China
| | - Yuanlin Guan
- Department of Research and Development, Hugobiotech Co. Ltd., Beijing, China
| | - Zhongyi Cheng
- Jingjie PTM BioLab (Hangzhou) Co. Ltd., Hangzhou, China
| | - Yejing Weng
- Jingjie PTM BioLab (Hangzhou) Co. Ltd., Hangzhou, China
| | - Weixin Wang
- Jingjie PTM BioLab (Hangzhou) Co. Ltd., Hangzhou, China
| | - Yaqi Duan
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Dong Kuang
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Sanpeng Xu
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Hanghang Cai
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | - Qin Xia
- Department of Pathology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dehua Yang
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Ming-Wei Wang
- The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xiangping Yang
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jianjun Zhang
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Chao Cheng
- Department of Medicine, Baylor College of Medicine, Houston, Texas, United States of America
| | - Liang Liu
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhongmin Liu
- Institute for Regenerative Medicine, Shanghai East Hospital, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Ren Liang
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Guopin Wang
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
| | | | - Han Xia
- Department of Research and Development, Hugobiotech Co. Ltd., Beijing, China
- School of Automation Science and Engineering, Faculty of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, China
| | - Tian Xia
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- Institute of Artificial Intelligence and Automation, Huazhong University of Science and Technology, Wuhan, China
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11
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White LA, Bisom TC, Grimes HL, Hayashi M, Lanchy JM, Lodmell JS. Tra2beta-Dependent Regulation of RIO Kinase 3 Splicing During Rift Valley Fever Virus Infection Underscores the Links Between Alternative Splicing and Innate Antiviral Immunity. Front Cell Infect Microbiol 2022; 11:799024. [PMID: 35127560 PMCID: PMC8807687 DOI: 10.3389/fcimb.2021.799024] [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: 10/21/2021] [Accepted: 12/28/2021] [Indexed: 12/14/2022] Open
Abstract
Rift Valley fever virus (RVFV) is an emerging pathogen that has potential to cause severe disease in humans and domestic livestock. Propagation of RVFV strain MP-12 is negatively impacted by the actions of RIOK3, a protein involved in the cellular immune response to viral infection. During RVFV infection, RIOK3 mRNA is alternatively spliced to produce an isoform that correlates with the inhibition of interferon β signaling. Here, we identify splicing factor TRA2-β (also known as TRA2beta and hTRA2-β) as a key regulator governing the relative abundance of RIOK3 splicing isoforms. Using RT-PCR and minigenes, we determined that TRA2-β interaction with RIOK3 pre-mRNA was necessary for constitutive splicing of RIOK3 mRNA, and conversely, lack of TRA2-β engagement led to increased alternative splicing. Expression of TRA2-β was found to be necessary for RIOK3's antiviral effect against RVFV. Intriguingly, TRA2-β mRNA is also alternatively spliced during RVFV infection, leading to a decrease in cellular TRA2-β protein levels. These results suggest that splicing modulation serves as an immune evasion strategy by RVFV and/or is a cellular mechanism to prevent excessive immune response. Furthermore, the results suggest that TRA2-β can act as a key regulator of additional steps of the innate immune response to viral infection.
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Affiliation(s)
- Luke Adam White
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Thomas C. Bisom
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT, United States
| | - Hunter L. Grimes
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Miyuki Hayashi
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT, United States
| | - Jean-Marc Lanchy
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - J. Stephen Lodmell
- Division of Biological Sciences, University of Montana, Missoula, MT, United States,Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, United States,*Correspondence: J. Stephen Lodmell,
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12
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Sun J, Li L, Hu J, Gao Y, Song J, Zhang X, Hu H. Time-course RNA-Seq profiling reveals isoform-level gene expression dynamics of the cGAS-STING pathway. Comput Struct Biotechnol J 2022; 20:6490-6500. [PMCID: PMC9686058 DOI: 10.1016/j.csbj.2022.11.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/21/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022] Open
Abstract
The cGAS-STING pathway, orchestrating complicated transcriptome-wide immune responses, is essential for host antiviral defense but can also drive immunopathology in severe COVID-19. Here, we performed time-course RNA-Seq experiments to dissect the transcriptome expression dynamics at the gene-isoform level after cGAS-STING pathway activation. The in-depth time-course transcriptome after cGAS-STING pathway activation within 12 h enabled quantification of 48,685 gene isoforms. By employing regression models, we obtained 13,232 gene isoforms with expression patterns significantly associated with the process of cGAS-STING pathway activation, which were named activation-associated isoforms. The combination of hierarchical and k-means clustering algorithms revealed four major expression patterns of activation-associated isoforms, including two clusters with increased expression patterns enriched in cell cycle, autophagy, antiviral innate-immune functions, and COVID-19 coronavirus disease pathway, and two clusters showing decreased expression pattern that mainly involved in ncRNA metabolism, translation process, and mRNA processing. Importantly, by merging four clusters of activation-associated isoforms, we identified three types of genes that underwent isoform usage alteration during the cGAS-STING pathway activation. We further found that genes exhibiting protein-coding and non-protein-coding gene isoform usage alteration were strongly enriched for the factors involved in innate immunity and RNA splicing. Notably, overexpression of an enriched splicing factor, EFTUD2, shifted transcriptome towards the cGAS-STING pathway activated status and promoted protein-coding isoform abundance of several key regulators of the cGAS-STING pathway. Taken together, our results revealed the isoform-level gene expression dynamics of the cGAS-STING pathway and uncovered novel roles of splicing factors in regulating cGAS-STING pathway mediated immune responses.
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13
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Liu W, Sun Y, Qiu X, Meng C, Song C, Tan L, Liao Y, Liu X, Ding C. Genome-Wide Analysis of Alternative Splicing during Host-Virus Interactions in Chicken. Viruses 2021; 13:v13122409. [PMID: 34960678 PMCID: PMC8703359 DOI: 10.3390/v13122409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022] Open
Abstract
The chicken is a model animal for the study of evolution, immunity and development. In addition to their use as a model organism, chickens also represent an important agricultural product. Pathogen invasion has already been shown to modulate the expression of hundreds of genes, but the role of alternative splicing in avian virus infection remains unclear. We used RNA-seq data to analyze virus-induced changes in the alternative splicing of Gallus gallus, and found that a large number of alternative splicing events were induced by virus infection both in vivo and in vitro. Virus-responsive alternative splicing events preferentially occurred in genes involved in metabolism and transport. Many of the alternatively spliced transcripts were also expressed from genes with a function relating to splicing or immune response, suggesting a potential impact of virus infection on pre-mRNA splicing and immune gene regulation. Moreover, exon skipping was the most frequent AS event in chickens during virus infection. This is the first report describing a genome-wide analysis of alternative splicing in chicken and contributes to the genomic resources available for studying host-virus interaction in this species. Our analysis fills an important knowledge gap in understanding the extent of genome-wide alternative splicing dynamics occurring during avian virus infection and provides the impetus for the further exploration of AS in chicken defense signaling and homeostasis.
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Affiliation(s)
- Weiwei Liu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Yingjie Sun
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Xusheng Qiu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Chunchun Meng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Cuiping Song
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Lei Tan
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Ying Liao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
| | - Xiufan Liu
- School of Veterinary Medicine, Yangzhou University, Yangzhou 225009, China;
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.L.); (Y.S.); (X.Q.); (C.M.); (C.S.); (L.T.); (Y.L.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China
- Correspondence: ; Tel.: +86-21-3429-3441
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14
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Liang J, Hong Z, Sun B, Guo Z, Wang C, Zhu J. The Alternatively Spliced Isoforms of Key Molecules in the cGAS-STING Signaling Pathway. Front Immunol 2021; 12:771744. [PMID: 34868032 PMCID: PMC8636596 DOI: 10.3389/fimmu.2021.771744] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/03/2021] [Indexed: 01/04/2023] Open
Abstract
Alternative splicing of pre-mRNA increases transcriptome and proteome diversity by generating distinct isoforms that encode functionally diverse proteins, thus affecting many biological processes, including innate immunity. cGAS-STING signaling pathway, whose key molecules also undergo alternative splicing, plays a crucial role in regulating innate immunity. Protein isoforms of key components in the cGAS-STING-TBK1-IRF3 axis have been detected in a variety of species. A chain of evidence showed that these protein isoforms exhibit distinct functions compared to their normal counterparts. The mentioned isoforms act as positive or negative modulators in interferon response via distinct mechanisms. Particularly, we highlight that alternative splicing serves a vital function for the host to avoid the overactivation of the cGAS-STING signaling pathway and that viruses can utilize alternative splicing to resist antiviral response by the host. These findings could provide insights for potential alternative splicing-targeting therapeutic applications.
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Affiliation(s)
- Jiaqian Liang
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Ze Hong
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Boyue Sun
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Zhaoxi Guo
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Chen Wang
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Juanjuan Zhu
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
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15
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Gokhale NS, Smith JR, Van Gelder RD, Savan R. RNA regulatory mechanisms that control antiviral innate immunity. Immunol Rev 2021; 304:77-96. [PMID: 34405416 DOI: 10.1111/imr.13019] [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: 06/18/2021] [Revised: 07/29/2021] [Accepted: 08/02/2021] [Indexed: 12/21/2022]
Abstract
From the initial sensing of viral nucleotides by pattern recognition receptors, through the induction of type I and III interferons (IFN), upregulation of antiviral effector proteins, and resolution of the inflammatory response, each step of innate immune signaling is under tight control. Though innate immunity is often associated with broad regulation at the level of gene transcription, RNA-centric post-transcriptional processes have emerged as critical mechanisms for ensuring a proper antiviral response. Here, we explore the diverse RNA regulatory mechanisms that modulate the innate antiviral immune response, with a focus on RNA sensing by RIG-I-like receptors (RLR), interferon (IFN) and IFN signaling pathways, viral pathogenesis, and host genetic variation that contributes to these processes. We address the post-transcriptional interactions with RNA-binding proteins, non-coding RNAs, transcript elements, and modifications that control mRNA stability, as well as alternative splicing events that modulate the innate immune antiviral response.
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Affiliation(s)
- Nandan S Gokhale
- Department of Immunology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Julian R Smith
- Department of Immunology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Rachel D Van Gelder
- Department of Immunology, School of Medicine, University of Washington, Seattle, Washington, USA
| | - Ram Savan
- Department of Immunology, School of Medicine, University of Washington, Seattle, Washington, USA
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16
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Liao KC, Garcia-Blanco MA. Role of Alternative Splicing in Regulating Host Response to Viral Infection. Cells 2021; 10:1720. [PMID: 34359890 PMCID: PMC8306335 DOI: 10.3390/cells10071720] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 01/26/2023] Open
Abstract
The importance of transcriptional regulation of host genes in innate immunity against viral infection has been widely recognized. More recently, post-transcriptional regulatory mechanisms have gained appreciation as an additional and important layer of regulation to fine-tune host immune responses. Here, we review the functional significance of alternative splicing in innate immune responses to viral infection. We describe how several central components of the Type I and III interferon pathways encode spliced isoforms to regulate IFN activation and function. Additionally, the functional roles of splicing factors and modulators in antiviral immunity are discussed. Lastly, we discuss how cell death pathways are regulated by alternative splicing as well as the potential role of this regulation on host immunity and viral infection. Altogether, these studies highlight the importance of RNA splicing in regulating host-virus interactions and suggest a role in downregulating antiviral innate immunity; this may be critical to prevent pathological inflammation.
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Affiliation(s)
- Kuo-Chieh Liao
- Genome Institute of Singapore, A*STAR, Singapore 138672, Singapore
| | - Mariano A. Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77550, USA
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77550, USA
- Institute of Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77550, USA
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857, Singapore
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17
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Chang MX. The negative regulation of retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) signaling pathway in fish. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 119:104038. [PMID: 33548290 DOI: 10.1016/j.dci.2021.104038] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 01/30/2021] [Accepted: 01/30/2021] [Indexed: 06/12/2023]
Abstract
At each stage of innate immune response, there are stimulatory and inhibitory signals that modulate the strength and character of the response. RIG-I-like receptor (RLR) signaling pathway plays pivotal roles in antiviral innate immune response. Recent studies have revealed the molecular mechanisms that viral infection leads to the activation of RLRs-mediated downstream signaling cascades and the production of type I interferons (IFNs). However, antiviral immune responses must be tightly regulated in order to prevent detrimental type I IFNs production. Previous reviews have highlighted negative regulation of RLR signaling pathway, which mainly target to directly regulate RIG-I, MDA5, MAVS and TBK1 function in mammals. In this review, we summarize recent advances in our understanding of negative regulators of RLR signaling pathway in teleost, with specific focus on piscine and viral regulatory mechanisms that directly or indirectly inhibit the function of RIG-I, MDA5, LGP2, MAVS, TRAF3, TBK1, IRF3 and IRF7 both in the steady state or upon viral infection. We also further discuss important directions for future studies, especially for non-coding RNAs and post-translational modifications via fish specific TRIM proteins. The knowledge of negative regulators of RLR signaling pathway in teleost will shed new light on the critical information for potential therapeutic purposes.
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Affiliation(s)
- Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, 430072, China; Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
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18
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Robinson EK, Jagannatha P, Covarrubias S, Cattle M, Smaliy V, Safavi R, Shapleigh B, Abu-Shumays R, Jain M, Cloonan SM, Akeson M, Brooks AN, Carpenter S. Inflammation drives alternative first exon usage to regulate immune genes including a novel iron-regulated isoform of Aim2. eLife 2021; 10:69431. [PMID: 34047695 PMCID: PMC8260223 DOI: 10.7554/elife.69431] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022] Open
Abstract
Determining the layers of gene regulation within the innate immune response is critical to our understanding of the cellular responses to infection and dysregulation in disease. We identified a conserved mechanism of gene regulation in human and mouse via changes in alternative first exon (AFE) usage following inflammation, resulting in changes to the isoforms produced. Of these AFE events, we identified 95 unannotated transcription start sites in mice using a de novo transcriptome generated by long-read native RNA-sequencing, one of which is in the cytosolic receptor for dsDNA and known inflammatory inducible gene, Aim2. We show that this unannotated AFE isoform of Aim2 is the predominant isoform expressed during inflammation and contains an iron-responsive element in its 5′UTR enabling mRNA translation to be regulated by iron levels. This work highlights the importance of examining alternative isoform changes and translational regulation in the innate immune response and uncovers novel regulatory mechanisms of Aim2.
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Affiliation(s)
- Elektra K Robinson
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States
| | - Pratibha Jagannatha
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States.,Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Sergio Covarrubias
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States
| | - Matthew Cattle
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Valeriya Smaliy
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States
| | - Rojin Safavi
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Barbara Shapleigh
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States
| | - Robin Abu-Shumays
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Miten Jain
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Suzanne M Cloonan
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, New York, United States
| | - Mark Akeson
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Angela N Brooks
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, United States
| | - Susan Carpenter
- Department of Molecular, Cell and Developmental Biology, University of California Santa Cruz, Santa Cruz, United States
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19
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Havranek KE, White LA, Bisom TC, Lanchy JM, Lodmell JS. The Atypical Kinase RIOK3 Limits RVFV Propagation and Is Regulated by Alternative Splicing. Viruses 2021; 13:v13030367. [PMID: 33652597 PMCID: PMC7996929 DOI: 10.3390/v13030367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 12/17/2022] Open
Abstract
In recent years, transcriptome profiling studies have identified changes in host splicing patterns caused by viral invasion, yet the functional consequences of the vast majority of these splicing events remain uncharacterized. We recently showed that the host splicing landscape changes during Rift Valley fever virus MP-12 strain (RVFV MP-12) infection of mammalian cells. Of particular interest, we observed that the host mRNA for Rio Kinase 3 (RIOK3) was alternatively spliced during infection. This kinase has been shown to be involved in pattern recognition receptor (PRR) signaling mediated by RIG-I like receptors to produce type-I interferon. Here, we characterize RIOK3 as an important component of the interferon signaling pathway during RVFV infection and demonstrate that RIOK3 mRNA expression is skewed shortly after infection to produce alternatively spliced variants that encode premature termination codons. This splicing event plays a critical role in regulation of the antiviral response. Interestingly, infection with other RNA viruses and transfection with nucleic acid-based RIG-I agonists also stimulated RIOK3 alternative splicing. Finally, we show that specifically stimulating alternative splicing of the RIOK3 transcript using a morpholino oligonucleotide reduced interferon expression. Collectively, these results indicate that RIOK3 is an important component of the mammalian interferon signaling cascade and its splicing is a potent regulatory mechanism capable of fine-tuning the host interferon response.
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Affiliation(s)
- Katherine E. Havranek
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; (K.E.H.); (L.A.W.); (J.-M.L.)
| | - Luke Adam White
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; (K.E.H.); (L.A.W.); (J.-M.L.)
| | - Thomas C. Bisom
- Department of Chemistry and Biochemistry, University of Montana, Missoula, MT 59812, USA;
| | - Jean-Marc Lanchy
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; (K.E.H.); (L.A.W.); (J.-M.L.)
| | - J. Stephen Lodmell
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA; (K.E.H.); (L.A.W.); (J.-M.L.)
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT 59812, USA
- Correspondence:
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20
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Chen J, Zhou XY, Li P, Li ZC, Zhang C, Sun YH, Wang GY, Chen DD, Lu LF, Li S. Molecular characterization of a cyprinid fish (Ancherythroculter nigrocauda) TBK1 and its kinase activity in IFN regulation. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 114:103805. [PMID: 32755617 DOI: 10.1016/j.dci.2020.103805] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 07/19/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
TANK-binding kinase 1 (TBK1) plays a vital role in activating interferon (IFN) production and positively regulating antiviral response in mammals. Research on more species of fish is necessary to clarify whether the function of fish TBK1 is conserved compared to that in mammals. Here, a cyprinid fish (Ancherythroculter nigrocauda) TBK1 (AnTBK1) was functionally identified and characterized. The full-length open reading frame (ORF) of AnTBK1 consists of 2184 nucleotides encoding 727 amino acids and contains a conserved Serine/Threonine protein kinase catalytic domain (S_TKc) in the N-terminal, similar to TBK1 in other species. The transcripts of AnTBK1 were found in all the tissues evaluated and the cellular distribution indicated that AnTBK1 was localized in the cytoplasm. In terms of functional identification, AnTBK1 induced a variety of IFN promoter activities as well as the expression of downstream IFN-stimulated genes (ISGs). In addition, AnTBK1 interacted with and significantly phosphorylated IFN regulatory factor 3 (IRF3), exhibiting the canonical kinase activity of TBK1. Finally, AnTBK1 presented strong antiviral activity against spring viremia of carp virus (SVCV) infection. Taken together, our research on the features and functions of AnTBK1 demonstrated that AnTBK1 plays a central role in IFN induction against SVCV infection.
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Affiliation(s)
- Jian Chen
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Xiao-Yu Zhou
- College of Fisheries and Life Science, Dalian Ocean University, Dalian, China; Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China
| | - Pei Li
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Zhuo-Cong Li
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China
| | - Can Zhang
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yan-Hong Sun
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Gui-Ying Wang
- Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, China
| | - Dan-Dan Chen
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Long-Feng Lu
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
| | - Shun Li
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
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21
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Revach OY, Liu S, Jenkins RW. Targeting TANK-binding kinase 1 (TBK1) in cancer. Expert Opin Ther Targets 2020; 24:1065-1078. [PMID: 32962465 PMCID: PMC7644630 DOI: 10.1080/14728222.2020.1826929] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/18/2020] [Indexed: 12/16/2022]
Abstract
INTRODUCTION TANK-binding kinase 1 (TBK1) is a Ser/Thr kinase with a central role in coordinating the cellular response to invading pathogens and regulating key inflammatory signaling cascades. While intact TBK1 signaling is required for successful anti-viral signaling, dysregulated TBK1 signaling has been linked to a variety of pathophysiologic conditions, including cancer. Several lines of evidence support a role for TBK1 in cancer pathogenesis, but the specific roles and regulation of TBK1 remain incompletely understood. A key challenge is the diversity of cellular processes that are regulated by TBK1, including inflammation, cell cycle, autophagy, energy homeostasis, and cell death. Nevertheless, evidence from pre-clinical cancer models suggests that targeting TBK1 may be an effective strategy for anti-cancer therapy in specific settings. AREAS COVERED This review provides an overview of the roles and regulation of TBK1 with a focus on cancer pathogenesis and drug targeting of TBK1 as an anti-cancer strategy. Relevant literature was derived from a PubMed search encompassing studies from 1999 to 2020. EXPERT OPINION TBK1 is emerging as a potential target for anti-cancer therapy. Inhibition of TBK1 alone may be insufficient to restrain the growth of most cancers; hence, combination strategies will likely be necessary. Improved understanding of tumor-intrinsic and tumor-extrinsic TBK1 signaling will inform novel therapeutic strategies.
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Affiliation(s)
- Or-yam Revach
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Shuming Liu
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Russell W. Jenkins
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA, USA
- Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA, USA
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22
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Zhang J, Wu XM, Hu YW, Chang MX. A Novel Transcript Isoform of TBK1 Negatively Regulates Type I IFN Production by Promoting Proteasomal Degradation of TBK1 and Lysosomal Degradation of IRF3. Front Immunol 2020; 11:580864. [PMID: 33101307 PMCID: PMC7554342 DOI: 10.3389/fimmu.2020.580864] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/08/2020] [Indexed: 01/28/2023] Open
Abstract
TANK-binding kinase 1 (TBK1), an IKK-related serine/threonine kinase, is pivotal for the induction of antiviral type I interferon (IFN) by TLR and RLR signaling pathways. In a previous study, we demonstrated that TBK1 spliced isoforms (TBK1_tv1 and TBK1_tv2) from zebrafish were dominant negative regulators in the RLR antiviral pathway by targeting the functional TBK1–IRF3 complex formation. In this study, we show that the third TBK1 isoform (namely TBK1_tv3) inhibits zebrafish type I IFN production by promoting TBK1 and IRF3 degradation. First, ectopic expression of TBK1_tv3 suppresses poly(I:C)- and Spring viremia of carp virus-induced type I IFN response, and also inhibits the up-regulation of IFN promoter activities stimulated by RIG-I, MDA5, MAVS, TBK1, and IRF3. Second, TBK1_tv3 targets TBK1 and IRF3 to impair the formation of TBK1 dimer, TBK1–IRF3 complex, and IRF3 dimer. Notably, TBK1_tv3 promotes the degradation of TBK1 through the ubiquitin–proteasome pathway and the degradation of IRF3 through the lysosomal pathway. Further analysis demonstrates that TBK1_tv3 promotes the degradation of TBK1 for K48-linked ubiquitination by targeting the K251, K256, and K271 sites of TBK1. Collectively, our results suggest a novel TBK1 isoform-mediated negative regulation mechanism, which serves to balance the production of type I IFN and ISGs.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xiao Man Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Yi Wei Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Aquaculture Disease Control, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.,University of the Chinese Academy of Sciences, Beijing, China.,Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, China
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23
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Xu L, Yu D, Peng L, Wu Y, Fan Y, Gu T, Yao YL, Zhong J, Chen X, Yao YG. An Alternative Splicing of Tupaia STING Modulated Anti-RNA Virus Responses by Targeting MDA5-LGP2 and IRF3. THE JOURNAL OF IMMUNOLOGY 2020; 204:3191-3204. [DOI: 10.4049/jimmunol.1901320] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/15/2020] [Indexed: 01/01/2023]
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24
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Lee FFY, Davidson K, Harris C, McClendon J, Janssen WJ, Alper S. NF-κB mediates lipopolysaccharide-induced alternative pre-mRNA splicing of MyD88 in mouse macrophages. J Biol Chem 2020; 295:6236-6248. [PMID: 32179652 DOI: 10.1074/jbc.ra119.011495] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 03/10/2020] [Indexed: 12/14/2022] Open
Abstract
Although a robust inflammatory response is needed to combat infection, this response must ultimately be terminated to prevent chronic inflammation. One mechanism that terminates inflammatory signaling is the production of alternative mRNA splice forms in the Toll-like receptor (TLR) signaling pathway. Whereas most genes in the TLR pathway encode positive mediators of inflammatory signaling, several, including that encoding the MyD88 signaling adaptor, also produce alternative spliced mRNA isoforms that encode dominant-negative inhibitors of the response. Production of these negatively acting alternatively spliced isoforms is induced by stimulation with the TLR4 agonist lipopolysaccharide (LPS); thus, this alternative pre-mRNA splicing represents a negative feedback loop that terminates TLR signaling and prevents chronic inflammation. In the current study, we investigated the mechanisms regulating the LPS-induced alternative pre-mRNA splicing of the MyD88 transcript in murine macrophages. We found that 1) the induction of the alternatively spliced MyD88 form is due to alternative pre-mRNA splicing and not caused by another RNA regulatory mechanism, 2) MyD88 splicing is regulated by both the MyD88- and TRIF-dependent arms of the TLR signaling pathway, 3) MyD88 splicing is regulated by the NF-κB transcription factor, and 4) NF-κB likely regulates MyD88 alternative pre-mRNA splicing per se rather than regulating splicing indirectly by altering MyD88 transcription. We conclude that alternative splicing of MyD88 may provide a sensitive mechanism that ensures robust termination of inflammation for tissue repair and restoration of normal tissue homeostasis once an infection is controlled.
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Affiliation(s)
- Frank Fang-Yao Lee
- Department of Biomedical Research, National Jewish Health, Denver, Colorado 80206; Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado 80206; Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Kevin Davidson
- Pulmonary and Critical Care, WakeMed Hospital, Raleigh, North Carolina 27610
| | - Chelsea Harris
- Department of Biomedical Research, National Jewish Health, Denver, Colorado 80206; Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado 80206; Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Jazalle McClendon
- Department of Medicine, National Jewish Health, Denver, Colorado 80206
| | - William J Janssen
- Department of Medicine, National Jewish Health, Denver, Colorado 80206; Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Scott Alper
- Department of Biomedical Research, National Jewish Health, Denver, Colorado 80206; Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado 80206; Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado 80045.
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25
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Janssen WJ, Danhorn T, Harris C, Mould KJ, Lee FFY, Hedin BR, D'Alessandro A, Leach SM, Alper S. Inflammation-Induced Alternative Pre-mRNA Splicing in Mouse Alveolar Macrophages. G3 (BETHESDA, MD.) 2020; 10:555-567. [PMID: 31810980 PMCID: PMC7003074 DOI: 10.1534/g3.119.400935] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/26/2019] [Indexed: 12/16/2022]
Abstract
Alveolar macrophages serve as central orchestrators of inflammatory responses in the lungs, both initiating their onset and promoting their resolution. However, the mechanisms that program macrophages for these dynamic responses are not fully understood. Over 95% of all mammalian genes undergo alternative pre-mRNA splicing. While alternative splicing has been shown to regulate inflammatory responses in macrophages in vitro, it has not been investigated on a genome-wide scale in vivo Here we used RNAseq to investigate alternative pre-mRNA splicing in alveolar macrophages isolated from lipopolysaccharide (LPS)-treated mice during the peak of inflammation and during its resolution. We found that lung inflammation induced substantial alternative pre-mRNA splicing in alveolar macrophages. The number of changes in isoform usage was greatest at the peak of inflammation and involved multiple classes of alternative pre-mRNA splicing events. Comparative pathway analysis of inflammation-induced changes in alternative pre-mRNA splicing and differential gene expression revealed overlap of pathways enriched for immune responses such as chemokine signaling and cellular metabolism. Moreover, alternative pre-mRNA splicing of genes in metabolic pathways differed in tissue resident vs. recruited (blood monocyte-derived) alveolar macrophages and corresponded to changes in core metabolism, including a switch to Warburg-like metabolism in recruited macrophages with increased glycolysis and decreased flux through the tricarboxylic acid cycle.
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Affiliation(s)
- William J Janssen
- Department of Medicine
- Division of Pulmonary Sciences and Critical Care Medicine, and
| | | | - Chelsea Harris
- Center for Genes, Environment and Health, and
- Department of Biomedical Research, National Jewish Health, Denver, CO, 80206
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045
| | - Kara J Mould
- Department of Medicine
- Division of Pulmonary Sciences and Critical Care Medicine, and
| | - Frank Fang-Yao Lee
- Center for Genes, Environment and Health, and
- Department of Biomedical Research, National Jewish Health, Denver, CO, 80206
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045
| | - Brenna R Hedin
- Center for Genes, Environment and Health, and
- Department of Biomedical Research, National Jewish Health, Denver, CO, 80206
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO, 80045
| | - Sonia M Leach
- Center for Genes, Environment and Health, and
- Department of Biomedical Research, National Jewish Health, Denver, CO, 80206
| | - Scott Alper
- Center for Genes, Environment and Health, and
- Department of Biomedical Research, National Jewish Health, Denver, CO, 80206
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO, 80045
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26
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Chauhan K, Kalam H, Dutt R, Kumar D. RNA Splicing: A New Paradigm in Host-Pathogen Interactions. J Mol Biol 2019; 431:1565-1575. [PMID: 30857970 DOI: 10.1016/j.jmb.2019.03.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 02/26/2019] [Accepted: 03/02/2019] [Indexed: 12/21/2022]
Abstract
RNA splicing brings diversity to the eukaryotic proteome. Different spliced variants of a gene may differ in their structure, function, localization, and stability influencing protein stoichiometry and physiological outcomes. Alternate spliced variants of different genes are known to associate with various chronic pathologies including cancer. Emerging evidence suggests precise regulation of splicing as fundamental to normal well-being. In this context, infection-induced alternative splicing has emerged as a new pivot of host function, which pathogenic microbes can alter-directly or indirectly-to tweak the host immune responses against the pathogen. The implications of these findings are vast, and although not explored much in the case of pathogenic infections, we present here examples from splicing mediated regulation of immune responses across a variety of conditions and explore how this fascinating finding brings a new paradigm to host-pathogen interactions.
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Affiliation(s)
- Komal Chauhan
- Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Haroon Kalam
- Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Ravi Dutt
- Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Dhiraj Kumar
- Cellular Immunology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
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27
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Ashraf U, Benoit-Pilven C, Lacroix V, Navratil V, Naffakh N. Advances in Analyzing Virus-Induced Alterations of Host Cell Splicing. Trends Microbiol 2018; 27:268-281. [PMID: 30577974 DOI: 10.1016/j.tim.2018.11.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 10/19/2018] [Accepted: 11/09/2018] [Indexed: 12/14/2022]
Abstract
Alteration of host cell splicing is a common feature of many viral infections which is underappreciated because of the complexity and technical difficulty of studying alternative splicing (AS) regulation. Recent advances in RNA sequencing technologies revealed that up to several hundreds of host genes can show altered mRNA splicing upon viral infection. The observed changes in AS events can be either a direct consequence of viral manipulation of the host splicing machinery or result indirectly from the virus-induced innate immune response or cellular damage. Analysis at a higher resolution with single-cell RNAseq, and at a higher scale with the integration of multiple omics data sets in a systems biology perspective, will be needed to further comprehend this complex facet of virus-host interactions.
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Affiliation(s)
- Usama Ashraf
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France; CNRS UMR3569, F-75015 Paris, France; Université Paris Diderot, Sorbonne Paris Cité EA302, F-75015 Paris, France
| | - Clara Benoit-Pilven
- INSERM U1028; CNRS UMR5292, Lyon Neuroscience Research Center, Genetic of Neuro-development Anomalies Team, F-69000 Lyon, France; Université Claude Bernard Lyon 1, CNRS UMR5558, Laboratoire de Biométrie et Biologie Evolutive, F-69622 Villeurbanne, France; EPI ERABLE, INRIA Grenoble Rhône-Alpes, F-38330 Montbonnot Saint-Martin, France
| | - Vincent Lacroix
- Université Claude Bernard Lyon 1, CNRS UMR5558, Laboratoire de Biométrie et Biologie Evolutive, F-69622 Villeurbanne, France; EPI ERABLE, INRIA Grenoble Rhône-Alpes, F-38330 Montbonnot Saint-Martin, France
| | - Vincent Navratil
- PRABI, Rhône Alpes Bioinformatics Center, UCBL, Université Claude Bernard Lyon 1, F-69000 Lyon, France; European Virus Bioinformatics Center, Leutragraben 1, D-07743 Jena, Germany
| | - Nadia Naffakh
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France; CNRS UMR3569, F-75015 Paris, France; Université Paris Diderot, Sorbonne Paris Cité EA302, F-75015 Paris, France.
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28
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Lu LF, Li S, Wang ZX, Liu SB, Chen DD, Zhang YA. Zebrafish NDRG1a Negatively Regulates IFN Induction by Promoting the Degradation of IRF7. THE JOURNAL OF IMMUNOLOGY 2018; 202:119-130. [PMID: 30504422 DOI: 10.4049/jimmunol.1800490] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 10/29/2018] [Indexed: 12/28/2022]
Abstract
Viral infection activates the transcription factor IFN regulatory factor 7 (IRF7), which plays a critical role in the induction of IFNs and innate antiviral immune response. How virus-induced IFN signaling is controlled in fish is not fully understood. In this study, we demonstrate that N-myc downstream-regulated gene 1a (NDRG1a) in zebrafish plays a role as a negative regulator for virus-triggered IFN induction. First, the activation of the IFN promoter stimulated by the polyinosinic-polycytidylic acid or spring viremia of carp virus was decreased by the overexpression of NDRG1a. Second, NDRG1a interacted with IRF7 and blocked the IFN transcription activated by IRF7. Furthermore, NDRG1a was phosphorylated by TANK-binding kinase 1 (TBK1) and promoted the K48-linked ubiquitination and degradation of IRF7. Finally, the overexpression of NDRG1a blunted the transcription of several IFN-stimulated genes, resulting in the host cells becoming susceptible to spring viremia of carp virus infection. Our findings suggest that fish NDRG1a negatively regulates the cellular antiviral response by targeting IRF7 for ubiquitination and degradation, providing insights into the novel role of NDRG1a on the innate antiviral immune response in fish.
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Affiliation(s)
- Long-Feng Lu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China
| | - Shun Li
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China
| | - Zhao-Xi Wang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.,University of Chinese Academy of Sciences, Beijing 10049, China; and
| | - Shu-Bo Liu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.,University of Chinese Academy of Sciences, Beijing 10049, China; and
| | - Dan-Dan Chen
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China.,State Key Laboratory of Agricultural Microbiology, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430070, China; .,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, China.,State Key Laboratory of Agricultural Microbiology, College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
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29
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Strand-Specific Dual RNA Sequencing of Bronchial Epithelial Cells Infected with Influenza A/H3N2 Viruses Reveals Splicing of Gene Segment 6 and Novel Host-Virus Interactions. J Virol 2018; 92:JVI.00518-18. [PMID: 29976658 DOI: 10.1128/jvi.00518-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/24/2018] [Indexed: 02/08/2023] Open
Abstract
Host-influenza virus interplay at the transcript level has been extensively characterized in epithelial cells. Yet, there are no studies that simultaneously characterize human host and influenza A virus (IAV) genomes. We infected human bronchial epithelial BEAS-2B cells with two seasonal IAV/H3N2 strains, Brisbane/10/07 and Perth/16/09 (reference strains for past vaccine seasons) and the well-characterized laboratory strain Udorn/307/72. Strand-specific RNA sequencing (RNA-seq) of the infected BEAS-2B cells allowed for simultaneous analysis of host and viral transcriptomes, in addition to pathogen genomes, to reveal changes in mRNA expression and alternative splicing (AS). In general, patterns of global and immune gene expression induced by the three IAVs were mostly shared. However, AS of host transcripts and small nuclear RNAs differed between the seasonal and laboratory strains. Analysis of viral transcriptomes showed deletions of the polymerase components (defective interfering-like RNAs) within the genome. Surprisingly, we found that the neuraminidase gene undergoes AS and that the splicing event differs between seasonal and laboratory strains. Our findings reveal novel elements of the host-virus interaction and highlight the importance of RNA-seq in identifying molecular changes at the genome level that may contribute to shaping RNA-based innate immunity.IMPORTANCE The use of massively parallel RNA sequencing (RNA-seq) has revealed insights into human and pathogen genomes and their evolution. Dual RNA-seq allows simultaneous dissection of host and pathogen genomes and strand-specific RNA-seq provides information about the polarity of the RNA. This is important in the case of negative-strand RNA viruses like influenza virus, which generate positive (complementary and mRNA) and negative-strand RNAs (genome) that differ in their potential to trigger innate immunity. Here, we characterize interactions between human bronchial epithelial cells and three influenza A/H3N2 strains using strand-specific dual RNA-seq. We focused on this subtype because of its epidemiological importance in causing significant morbidity and mortality during influenza epidemics. We report novel elements that differ between seasonal and laboratory strains highlighting the complexity of the host-virus interplay at the RNA level.
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30
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Innate responses to gene knockouts impact overlapping gene networks and vary with respect to resistance to viral infection. Proc Natl Acad Sci U S A 2018; 115:E3230-E3237. [PMID: 29559532 DOI: 10.1073/pnas.1720464115] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Analyses of the levels of mRNAs encoding IFIT1, IFI16, RIG-1, MDA5, CXCL10, LGP2, PUM1, LSD1, STING, and IFNβ in cell lines from which the gene encoding LGP2, LSD1, PML, HDAC4, IFI16, PUM1, STING, MDA5, IRF3, or HDAC 1 had been knocked out, as well as the ability of these cell lines to support the replication of HSV-1, revealed the following: (i) Cell lines lacking the gene encoding LGP2, PML, or HDAC4 (cluster 1) exhibited increased levels of expression of partially overlapping gene networks. Concurrently, these cell lines produced from 5 fold to 12 fold lower yields of HSV-1 than the parental cells. (ii) Cell lines lacking the genes encoding STING, LSD1, MDA5, IRF3, or HDAC 1 (cluster 2) exhibited decreased levels of mRNAs of partially overlapping gene networks. Concurrently, these cell lines produced virus yields that did not differ from those produced by the parental cell line. The genes up-regulated in cell lines forming cluster 1, overlapped in part with genes down-regulated in cluster 2. The key conclusions are that gene knockouts and subsequent selection for growth causes changes in expression of multiple genes, and hence the phenotype of the cell lines cannot be ascribed to a single gene; the patterns of gene expression may be shared by multiple knockouts; and the enhanced immunity to viral replication by cluster 1 knockout cell lines but not by cluster 2 cell lines suggests that in parental cells, the expression of innate resistance to infection is specifically repressed.
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Hu Y, Huang Y, Liu J, Zhang J, Qin Q, Huang X. TBK1 from orange-spotted grouper exerts antiviral activity against fish viruses and regulates interferon response. FISH & SHELLFISH IMMUNOLOGY 2018; 73:92-99. [PMID: 29222027 DOI: 10.1016/j.fsi.2017.12.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/06/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
TANK-binding kinase-1 (TBK1) has been well studied in mammals because of its importance in type I interferon induction in antiviral immunity. However, the roles of fish TBK1 in virus infection still remained largely uncertain. In the current study, a TBK1 homolog from orange-spotted grouper (Epinephelus coioides) (EcTBK1) was cloned and its roles in fish viral infections were investigated. Sequence analysis showed that EcTBK1 encoded a 723-amino acid peptide which shared 98% and 73% identity to large yellow croaker (Larimichthys crocea) and human (homo sapiens), respectively. Multiple sequence alignments indicated that EcTBK1 contained conserved domains, including N-terminal kinase domain (KD), the middle ubiquitin-like domain (ULD) and C-terminal coiled-coil (CC) domains. The tissue distribution profiles demonstrated that EcTBK1 gene was constitutively expressed in all examined tissues, with predominant expression in intestine. Temporal expression analysis in vitro showed that the expression levels of EcTBK1 were significantly up-regulated in response to both red-spotted grouper nervous necrosis virus (RGNNV) and Singapore grouper iridovirus (SGIV) infection, suggested that EcTBK1 might exert crucial roles in fish virus infection. Subcellular localization indicated that EcTBK1 expression was primarily in the cytoplasm in GS cells. The ectopic expression of EcTBK1 significantly inhibited both SGIV and RGNNV replication. Furthermore, EcTBK1 overexpression significantly increased the expression levels of interferon related cytokines and pro-inflammatory factors. In addition, the overexpression of EcTBK1 increased the IRF3- and IRF7-regulated interferon promoter ISRE and IFN activity, and the regulatory effect on interferon immune response were dependent on its kinase domain. Together, we speculated that grouper TBK1 exerted antiviral activity against iridovirus and nodavirus via regulating the interferon immune and inflammatory response.
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Affiliation(s)
- Yin Hu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Youhua Huang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Jiaxin Liu
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Jingcheng Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Qiwei Qin
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China.
| | - Xiaohong Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China; College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; University of Chinese Academy of Sciences, Beijing, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
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32
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Hu YW, Zhang J, Wu XM, Cao L, Nie P, Chang MX. TANK-Binding Kinase 1 (TBK1) Isoforms Negatively Regulate Type I Interferon Induction by Inhibiting TBK1-IRF3 Interaction and IRF3 Phosphorylation. Front Immunol 2018; 9:84. [PMID: 29441066 PMCID: PMC5797597 DOI: 10.3389/fimmu.2018.00084] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 01/11/2018] [Indexed: 12/21/2022] Open
Abstract
TANK-binding kinase 1 (TBK1) is an important serine/threonine-protein kinase that mediates phosphorylation and nuclear translocation of IRF3, which contributes to induction of type I interferons (IFNs) in the innate antiviral response. In mammals, TBK1 spliced isoform negatively regulates the virus-triggered IFN-β signaling pathway by disrupting the interaction between retinoic acid-inducible gene I (RIG-I) and mitochondria antiviral-signaling protein (MAVS). However, it is still unclear whether alternative splicing patterns and the function of TBK1 isoform(s) exist in teleost fish. In this study, we identify two alternatively spliced isoforms of TBK1 from zebrafish, termed TBK1_tv1 and TBK1_tv2. Both TBK1_tv1 and TBK1_tv2 contain an incomplete STKc_TBK1 domain. Moreover, the UBL_TBK1_like domain is also missing for TBK1_tv2. TBK1_tv1 and TBK1_tv2 are expressed in zebrafish larvae. Overexpression of TBK1_tv1 and TBK1_tv2 inhibits RIG-I-, MAVS-, TBK1-, and IRF3-mediated activation of IFN promoters in response to spring viremia of carp virus infection. Also, TBK1_tv1 and TBK1_tv2 inhibit expression of IFNs and IFN-stimulated genes induced by MAVS and TBK1. Mechanistically, TBK1_tv1 and TBK1_tv2 competitively associate with TBK1 and IRF3 to disrupt the formation of a functional TBK1-IRF3 complex, impeding the phosphorylation of IRF3 mediated by TBK1. Collectively, these results demonstrate that TBK1 spliced isoforms are dominant negative regulators in the RIG-I/MAVS/TBK1/IRF3 antiviral pathway by targeting the functional TBK1-IRF3 complex formation. Identification and functional characterization of piscine TBK1 spliced isoforms may contribute to understanding the role of TBK1 expression in innate antiviral response.
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Affiliation(s)
- Yi Wei Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jie Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Xiao Man Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Lu Cao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Pin Nie
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Wuhan, China
| | - Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Aquaculture Disease Control, Ministry of Agriculture, Wuhan, China
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Cheng Y, Ma J, Liu Y, Gao Q, Yan Y, Wang H, Ding C, Sun J. Chicken TBK1 interacts with STING and is involved in IFN-β signaling regulation. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 77:200-209. [PMID: 28837824 DOI: 10.1016/j.dci.2017.08.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 08/19/2017] [Accepted: 08/19/2017] [Indexed: 06/07/2023]
Abstract
TANK-binding kinase 1 (TBK1) is an essential serine/threonine-protein kinase required for the Toll-like receptor (TLR)- and retinoic acid-inducible gene I (RIG-I) -mediated induction of type I IFN. Through endogenous Co-IP and LC-MS/MS, we identified chicken TBK1 (chTBK1) as a chSTING-interactive protein. Through exogenous Co-IP assay in transfected cells, we confirmed the interaction between chSTING and chTBK1. To better understand the biological role of chTBK1 in the chSTING-mediated IFN pathway, we cloned the chTBK1 and investigated its biological functions. Quantitative RT-PCR showed that chTBK1 mRNA was widely expressed in different tissues. The overexpression of chTBK1 in DF-1 cells induced the expression of IFN-β and ISGs and inhibited AIV viral replication. We identified indispensable domains of chTBK1 on IFN-β production via the generation of various chTBK1 mutant forms. Together, we identified the chTBK1 as a chSTING interactive protein and concluded that chTBK1 is involved in chSTING-triggered IFN-β signaling in chicken cells.
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Affiliation(s)
- Yuqiang Cheng
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Jingjiao Ma
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yunxia Liu
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Quanxin Gao
- The Center for Disease Prevention and Control of Baoshan, Shanghai 201901, China
| | - Yaxian Yan
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hengan Wang
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China.
| | - Jianhe Sun
- Shanghai Key Laboratory of Veterinary Biotechnology, Key Laboratory of Urban Agriculture (South), Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
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Zhang LJ, Sen GL, Ward NL, Johnston A, Chun K, Chen Y, Adase C, Sanford JA, Gao N, Chensee M, Sato E, Fritz Y, Baliwag J, Williams MR, Hata T, Gallo RL. Antimicrobial Peptide LL37 and MAVS Signaling Drive Interferon-β Production by Epidermal Keratinocytes during Skin Injury. Immunity 2017; 45:119-30. [PMID: 27438769 DOI: 10.1016/j.immuni.2016.06.021] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 03/30/2016] [Accepted: 05/02/2016] [Indexed: 02/02/2023]
Abstract
Type 1 interferons (IFNs) promote inflammation in the skin but the mechanisms responsible for inducing these cytokines are not well understood. We found that IFN-β was abundantly produced by epidermal keratinocytes (KCs) in psoriasis and during wound repair. KC IFN-β production depended on stimulation of mitochondrial antiviral-signaling protein (MAVS) by the antimicrobial peptide LL37 and double stranded-RNA released from necrotic cells. MAVS activated downstream TBK1 (TANK-Binding Kinase 1)-AKT (AKT serine/threonine kinase 1)-IRF3 (interferon regulatory factor 3) signaling cascade leading to IFN-β production and then promoted maturation of dendritic cells. In mice, the production of epidermal IFN-β by LL37 required MAVS, and human wounded and/or psoriatic skin showed activation of MAVS-associated IRF3 and induction of MAVS and IFN-β gene signatures. These findings show that KCs are an important source of IFN-β and MAVS is critical to this function, and demonstrates how the epidermis triggers unwanted skin inflammation under disease conditions.
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Affiliation(s)
- Ling-Juan Zhang
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - George L Sen
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, San Diego, La Jolla, CA 92093, USA
| | - Nicole L Ward
- Department of Dermatology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Andrew Johnston
- Department of Dermatology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kimberly Chun
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yifang Chen
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, San Diego, La Jolla, CA 92093, USA
| | - Christopher Adase
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - James A Sanford
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nina Gao
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Melanie Chensee
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emi Sato
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yi Fritz
- Department of Dermatology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jaymie Baliwag
- Department of Dermatology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael R Williams
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Tissa Hata
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Richard L Gallo
- Department of Dermatology, University of California, San Diego, La Jolla, CA 92093, USA.
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Alternative Pre-mRNA Splicing in Mammals and Teleost Fish: A Effective Strategy for the Regulation of Immune Responses Against Pathogen Infection. Int J Mol Sci 2017; 18:ijms18071530. [PMID: 28714877 PMCID: PMC5536018 DOI: 10.3390/ijms18071530] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 07/10/2017] [Accepted: 07/12/2017] [Indexed: 12/14/2022] Open
Abstract
Pre-mRNA splicing is the process by which introns are removed and the protein coding elements assembled into mature mRNAs. Alternative pre-mRNA splicing provides an important source of transcriptome and proteome complexity through selectively joining different coding elements to form mRNAs, which encode proteins with similar or distinct functions. In mammals, previous studies have shown the role of alternative splicing in regulating the function of the immune system, especially in the regulation of T-cell activation and function. As lower vertebrates, teleost fish mainly rely on a large family of pattern recognition receptors (PRRs) to recognize pathogen-associated molecular patterns (PAMPs) from various invading pathogens. In this review, we summarize recent advances in our understanding of alternative splicing of piscine PRRs including peptidoglycan recognition proteins (PGRPs), nucleotide binding and oligomerization domain (NOD)-like receptors (NLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) and their downstream signaling molecules, compared to splicing in mammals. We also discuss what is known and unknown about the function of splicing isoforms in the innate immune responses against pathogens infection in mammals and teleost fish. Finally, we highlight the consequences of alternative splicing in the innate immune system and give our view of important directions for future studies.
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A Cytoplasmic RNA Virus Alters the Function of the Cell Splicing Protein SRSF2. J Virol 2017; 91:JVI.02488-16. [PMID: 28077658 DOI: 10.1128/jvi.02488-16] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 01/05/2017] [Indexed: 11/20/2022] Open
Abstract
To replicate efficiently, viruses must create favorable cell conditions and overcome cell antiviral responses. We previously reported that the reovirus protein μ2 from strain T1L, but not strain T3D, represses one antiviral response: alpha/beta interferon signaling. We report here that T1L, but not T3D, μ2 localizes to nuclear speckles, where it forms a complex with the mRNA splicing factor SRSF2 and alters its subnuclear localization. Reovirus replicates in cytoplasmic viral factories, and there is no evidence that reovirus genomic or messenger RNAs are spliced, suggesting that T1L μ2 might target splicing of cell RNAs. Indeed, RNA sequencing revealed that reovirus T1L, but not T3D, infection alters the splicing of transcripts for host genes involved in mRNA posttranscriptional modifications. Moreover, depletion of SRSF2 enhanced reovirus replication and cytopathic effect, suggesting that T1L μ2 modulation of splicing benefits the virus. This provides the first report of viral antagonism of the splicing factor SRSF2 and identifies the viral protein that determines strain-specific differences in cell RNA splicing.IMPORTANCE Efficient viral replication requires that the virus create favorable cell conditions. Many viruses accomplish this by repressing specific antiviral responses. We demonstrate here that some mammalian reoviruses, RNA viruses that replicate strictly in the cytoplasm, express a protein variant that localizes to nuclear speckles, where it targets a cell mRNA splicing factor. Infection with a reovirus strain that targets this splicing factor alters splicing of cell mRNAs involved in the maturation of many other cell mRNAs. Depletion of this cell splicing factor enhances reovirus replication and cytopathic effect. Our results provide the first evidence of viral antagonism of this splicing factor and suggest that downstream consequences to the cell are global and benefit the virus.
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Zhang L, Chen WQ, Hu YW, Wu XM, Nie P, Chang MX. TBK1-like transcript negatively regulates the production of IFN and IFN-stimulated genes through RLRs-MAVS-TBK1 pathway. FISH & SHELLFISH IMMUNOLOGY 2016; 54:135-143. [PMID: 27060200 DOI: 10.1016/j.fsi.2016.04.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 04/02/2016] [Accepted: 04/05/2016] [Indexed: 06/05/2023]
Abstract
TANK-binding kinase 1 (TBK1) is an essential serine/threonine-protein kinase required for Toll-like receptor (TLR)- and retinoic acid-inducible gene I (RIG-I) -mediated induction of type I IFN and host antiviral defense. In the present study, TBK1-like transcript, namely TBK1L, was cloned from zebrafish. Compared with TBK1, TBK1L contains an incomplete S_TKc domain, and lacks UBL_TBK1_like domain. Realtime PCR showed that TBK1L was constitutively produced in embryos, early larvae and ZF4 cells, and unchanged in ZF4 cells following SVCV infection. Overexpression of TBK1 but not TBK1L resulted in significant activation of zebrafish IFN1 and IFN3 promoters. Similarly, TBK1L had little impact on the antiviral state of the cells. However, the overexpression of TBK1L negatively regulated the induction of zebrafish IFN1 and/or IFN3 promoters mediated by the retinoic acid-inducible gene I-like receptors (RLRs), MAVS and TBK1. In addition, the overexpression of TBK1L in zebrafish embryos led to the decreased production of many IFN-stimulated genes induced by TBK1. Collectively, these data support that zebrafish TBK1L negatively regulates RLRs-MAVS-TBK1 pathway.
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Affiliation(s)
- Lin Zhang
- College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei Province 430070, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China
| | - Wen Qin Chen
- Hubei Vocational College of Bio-technology, Wuhan, Hubei Province 430070, China
| | - Yi Wei Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - Xiao Man Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China; Graduate University of Chinese Academy of Sciences, Beijing 100039, China
| | - P Nie
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China
| | - Ming Xian Chang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China.
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Zhang DL, Yu DH, Chen J, Fan S, Wang ZY. Expression profiles and interaction suggest TBK1 can be regulated by Nrdp1 in response to immune stimulation in large yellow croaker Larimichthys crocea. FISH & SHELLFISH IMMUNOLOGY 2015; 46:745-752. [PMID: 26291490 DOI: 10.1016/j.fsi.2015.08.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Revised: 08/11/2015] [Accepted: 08/13/2015] [Indexed: 06/04/2023]
Abstract
TBK1 has been extensively studied in mammals because of its important roles as a molecular bridge, linking the TLRs (TLR3 and TLR4) and RLRs signals to activate transcriptional factors IRF3 and IRF7 for IFN-I production. However, the information on molecular and functional characteristics of TBK1 in teleosts is limited. In this study, the molecular characterization and immune response of TBK1 in Larimichthys crocea (named as LcTBK1) as well as its interaction with Nrdp1 were investigated. Sequence analysis demonstrated that LcTBK1 included four functional motifs, the N-terminal protein kinase domain and ATP-binding site, middle ULD and C-terminal coiled-coil domain. The tissue expression profiles indicated that LcTBK1 gene was constitutively expressed in the twelve tissues examined, with high expression in brain. Temporal expression analysis showed that LcTBK1 mRNA was obviously increased in the liver after injection of LPS, Poly I:C and inactive Vibrio parahaemolyticus, however, declined at some time points in spleen and head-kidney. Furthermore, we found that LcTBK1 can interact with LcNrdp1, an E3 ubiquitin ligase that involved in immune response to Cryptocaryon irritans infection in L. crocea. The qPCR showed that LcNrdp1 was also significantly up-regulated in liver, down-regualted at some time points in spleen and head-kidney after LPS, Poly I:C and inactive V. parahaemolyticus injection, although the expression patterns of the two genes after the three treatments were different in change magnitude and up-regulation timespan. These results suggested that LcTBK1 was involved in L. crocea defense against the pathogen infection and can be regulated by Nrdp1 in PPRs signaling pathway of fishes.
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Affiliation(s)
- Dong Ling Zhang
- Key Laboratory of Healthy Mariculture for The East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, PR China
| | - Da Hui Yu
- South China Sea Resource Exploitation and Protection Collaborative Innovation Center (SCS-REPIC), South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, PR China
| | - Jian Chen
- Key Laboratory of Healthy Mariculture for The East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, PR China
| | - Sigang Fan
- South China Sea Resource Exploitation and Protection Collaborative Innovation Center (SCS-REPIC), South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, 510300, PR China
| | - Zhi Yong Wang
- Key Laboratory of Healthy Mariculture for The East China Sea, Ministry of Agriculture, Fisheries College, Jimei University, Xiamen 361021, PR China.
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Lu LF, Li S, Lu XB, Zhang YA. Functions of the two zebrafish MAVS variants are opposite in the induction of IFN1 by targeting IRF7. FISH & SHELLFISH IMMUNOLOGY 2015; 45:574-582. [PMID: 25989622 DOI: 10.1016/j.fsi.2015.05.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 05/05/2015] [Accepted: 05/10/2015] [Indexed: 06/04/2023]
Abstract
IFNs create the first line of host cells to defense viral infection, however, unrestricted expression of IFN can be hazardous to the host. IRF7 is the master regulator of type I IFN expression. To our knowledge, non research about the inhibition of IFN expression by targeting IRF7 has been reported in fish. In this study, we reported that the splicing variant of wildtype MAVS (MAVS_tv1), MAVS_tv2, negatively regulated IRF7-mediated IFN production. Firstly, in vivo, the transcriptional levels of MAVS_tv2 in trunk kidney and spleen from the zebrafish infected with SVCV were monitored. Then, in vitro, the protein expression pattern of MAVS_tv2 in zebrafish cell lines was detected using anti-MAVS_tv2 antibody. Furthermore, overexpression of MAVS_tv2 decreased the activation of IFN1 promoter that induced by IRF7 in a dose-dependent manner, whereas it had little effect on IRF3, a close relative of IRF7. In addition, such inhibition was also observed in IRF7-mediated epcIFN promoter and ISRE activities, but not in the activation of the promoters of type II IFNs and NF-ĸB, due to IRF7 not regulating their expression. Lastly, overexpression of MAVS_tv2 decreased the transcriptional levels of several IFN-stimulated genes activated by IRF7. These findings suggest that MAVS_tv2 is a negative regulator of IFN1 by targeting IRF7.
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Affiliation(s)
- Long-Feng Lu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shun Li
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiao-Bing Lu
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yong-An Zhang
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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Feng X, Su J, Yang C, Yan N, Rao Y, Chen X. Molecular characterizations of grass carp (Ctenopharyngodon idella) TBK1 gene and its roles in regulating IFN-I pathway. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 45:278-290. [PMID: 24704212 DOI: 10.1016/j.dci.2014.03.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 03/06/2014] [Accepted: 03/26/2014] [Indexed: 06/03/2023]
Abstract
TANK-binding kinase 1 (TBK1), a kinase at the crossroads of multiple IFN-inducing signaling pathways, plays essential roles in both antiviral and antibacterial innate immunity in mammals. Here, TBK1 gene (10339bp) was identified and characterized from grass carp Ctenopharyngodon idella (CiTBK1). The genomic sequence is shorter than other orthologs in vertebrate, and a promoter region is found in intron 1. mRNA expression of CiTBK1 was widespread in fifteen tissues investigated, and was up-regulated post GCRV challenge in vivo and in vitro, as well as after stimulation of viral/bacterial PAMPs in vitro. CiTBK1 mediates IFN-I signal pathway through over-expression experiment. Post GCRV challenge, CiTBK1 over-expression inhibits viral infection by induction of CiIFN-I and CiMx1 mainly via CiIRF7. In CiTBK1 over-expression cells, mRNA expressions of CiIRF3, CiIRF7 and CiIFN-I were inhibited, whereas CiMx1 was facilitated after poly I:C stimulation, comparing to those in control group. The result indicated that CiMx1 expression mediated by CiTBK1 is in IFN-I independent way after poly I:C stimulation. However, over-expression of CiTBK1 diminishes LPS-induced expressions of CiIRF3 and CiIRF7 but promotes the induction of CiIFN-I and CiMx1 in comparison with the control, which suggests that CiTBK1-triggered IFN-I activation is in IRF3/IRF7-independent manner after LPS stimulation. Notably, over-expression of CiTBK1 negatively regulated PGN-induced IRF3, IRF7, IFN-I and Mx1 immune response. Taken together, CiTBK1 participates in broad antiviral and antibacterial immune responses in different manners, and keeps regulatory balance that prevents harmful effects from excessive activation.
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Affiliation(s)
- Xiaoli Feng
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China
| | - Jianguo Su
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China.
| | - Chunrong Yang
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China
| | - Nana Yan
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China
| | - Youliang Rao
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China
| | - Xiaohui Chen
- College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling 712100, China
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Chen H, Pei R, Zhu W, Zeng R, Wang Y, Wang Y, Lu M, Chen X. An Alternative Splicing Isoform of MITA Antagonizes MITA-Mediated Induction of Type I IFNs. THE JOURNAL OF IMMUNOLOGY 2014; 192:1162-70. [DOI: 10.4049/jimmunol.1300798] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Wang J, Yang B, Hu Y, Zheng Y, Zhou H, Wang Y, Ma Y, Mao K, Yang L, Lin G, Ji Y, Wu X, Sun B. Negative regulation of Nmi on virus-triggered type I IFN production by targeting IRF7. THE JOURNAL OF IMMUNOLOGY 2013; 191:3393-9. [PMID: 23956435 DOI: 10.4049/jimmunol.1300740] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Viral infection causes host cells to produce type I IFNs, which play a critical role in viral clearance. IFN regulatory factor (IRF) 7 is the master regulator of type I IFN-dependent immune responses. In this article, we report that N-Myc and STATs interactor (Nmi), a Sendai virus-inducible protein, interacted with IRF7 and inhibited virus-triggered type I IFN production. The overexpression of Nmi inhibited the Sendai virus-triggered induction of type I IFNs, whereas the knockdown of Nmi promoted IFN production. Furthermore, the enhanced production of IFNs resulting from Nmi knockdown was sufficient to protect cells from infection by vesicular stomatitis virus. In addition, Nmi was found to promote the K48-linked ubiquitination of IRF7 and the proteasome-dependent degradation of this protein. Finally, an impairment of antiviral responses is also detectable in Nmi-transgenic mice. These findings suggest that Nmi is a negative regulator of the virus-triggered induction of type I IFNs that targets IRF7.
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Affiliation(s)
- Jie Wang
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
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Regulation of RLR-mediated innate immune signaling – It is all about keeping the balance. Eur J Cell Biol 2012; 91:36-47. [DOI: 10.1016/j.ejcb.2011.01.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Revised: 01/27/2011] [Accepted: 01/27/2011] [Indexed: 12/25/2022] Open
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Koop A, Lepenies I, Braum O, Davarnia P, Scherer G, Fickenscher H, Kabelitz D, Adam-Klages S. Novel splice variants of human IKKε negatively regulate IKKε-induced IRF3 and NF-kB activation. Eur J Immunol 2010; 41:224-34. [DOI: 10.1002/eji.201040814] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/22/2010] [Accepted: 10/18/2010] [Indexed: 01/08/2023]
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Regulation of virus-triggered type I interferon signaling by cellular and viral proteins. ACTA ACUST UNITED AC 2010; 5:12-31. [PMID: 32215003 PMCID: PMC7088834 DOI: 10.1007/s11515-010-0013-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Accepted: 12/15/2009] [Indexed: 02/07/2023]
Abstract
Host pattern recognition receptors (PRRs) recognize invading viral pathogens and initiate a series of signaling cascades that lead to the expression of type I interferons (IFNs) and inflammatory cytokines. During the past decade, significant progresses have been made to characterize PRRs such as Toll-like receptors (TLRs) and RIG-I-like receptors (RLRs) and elucidate the molecular mechanisms of TLR- and RLR-mediated signaling. To avoid excessive and harmful immune effects caused by over-activation of these signaling pathways, host cells adopt a number of strategies to regulate them. In addition, invading viruses also employ a variety of mechanisms to inhibit the production of type I IFNs, thereby evading the supervision and clearance by the host. In this review, we briefly summarize the TLR- and RLR-mediated type I IFN signaling and then focus on the mechanisms by which host cellular and viral components regulate the expression of type I IFNs.
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