Retinoic Acid Inducible Gene-I like Receptors Activate Snail to Limit RNA Viral Infections

2021 ◽  
Author(s):  
Dhiviya Vedagiri ◽  
Divya Gupta ◽  
Anurag Mishra ◽  
Gayathri Krishna ◽  
Meenakshi Bhaskar ◽  
...  
Keyword(s):  
Viral Infections ◽  
Epithelial Mesenchymal Transition ◽  
Ectopic Expression ◽  
Antiviral Response ◽  
Poly I:C ◽  
Type I ◽  
Type I Ifn ◽  
Mesenchymal Transition ◽  
Type I Ifns ◽  
General Response

RLRs are important cytosolic PRRs that sense viral RNA before mounting a response leading to the activation of Type-I IFNs. Several viral infections induce epithelial-mesenchymal transition (EMT), even as its significance remains unclear. Here, we describe that EMT or EMT like process is a general response to viral infections. Our studies identify a previously unknown mechanism of regulation of an important EMT-TF Snail during RNA viral infections, and describe its possible implication. RNA viral infections, poly (I:C) transfection, and ectopic expression of RLR components induced Snail levels, indicating that RLR pathway could regulate its expression. Detailed examination using MAVS-KO cells established that MAVS is essential in this regulation. We identified two ISREs in SNAI1 promoter region and demonstrated that they are important in its transcriptional activation by phosphorylated IRF3. Increasing the levels of Snail activated RLR pathway and dramatically limited replication of RNA viruses DENV, JEV and VSV, pointing to their antiviral functions. Knock-down of Snail resulted in considerable increase in JEV titer, validating its antiviral functions. Finally, TGF-β mediated IFNB activation was dependent on Snail levels, confirming its important role in Type-I IFN activation. Thus, EMT-TF Snail is transcriptionally co-regulated with Type-I IFN by RLRs and in turn promotes RLR pathway, further strengthening the antiviral state in the cell. Our work identified an interesting mechanism of regulation of Snail that demonstrates potential co-regulation of multiple innate antiviral pathways triggered by RLRs. Identification of antiviral functions of Snail also provides an opportunity to expand the sphere of RLR signaling. IMPORTANCE RLRs sense viral genomic RNA or the dsRNA intermediates and trigger the activation of Type I IFNs. Snail transcription factor, commonly associated with epithelial-mesenchymal transition, has been reported to facilitate EMT in several viral infections. Much of these reports come from oncoviruses, leading to the speculation that EMT induced during infection is an important factor in the oncogenesis triggered by these infections. However, our studies reveal that EMT or EMT like processes during viral infections have important functions in antiviral response. We have characterized a new mechanism of transcriptional regulation of Snail by IRF3 through ISRE in their promoters and this finding could have importance in non-viral contexts as well. We also identify that EMT-TF Snail promotes antiviral status of the infected cells through RLR pathway. This work characterizes a new regulatory mechanism of activation of Snail and establishes its unidentified function in antiviral response.

scholarly journals Retinoic Acid Inducible Gene-I like Receptors Activate Snail and Slug to Limit RNA Viral Infections

2020 ◽  
Author(s):  
Dhiviya Vedagiri ◽  
Dviya Gupta ◽  
Anurag Mishra ◽  
Gayathri Krishna ◽  
Meenakshi Bhaskar ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Viral Infections ◽  
Ectopic Expression ◽  
Detailed Examination ◽  
Poly I:C ◽  
Luciferase Assay ◽  
Type I ◽  
Transcription Regulator ◽  
Type I Ifns ◽  
Inducible Gene

RLRs sense cytosolic non-self RNAs including viral RNAs before mounting a response leading to the activation of Type-I IFNs. Here, we identify a previously unknown regulation of Snail, a transcription regulator known in EMT, during RNA viral infections and describe its possible implication. RNA viral infections, poly (I:C) transfection and ectopic expression of RLR components activated Snail and Slug in epithelial cells. Detailed examination revealed that MAVS and phosphorylated IRF3 are essential in this regulation. We identified two ISREs in SNAI1 promoter region and their alterations rendered the promoter non-responsive to phospho-IRF3 in luciferase assay. Ectopic expression of Snail and Slug activated RLR pathway and dramatically limited RNA viral infections in epithelial cells pointing to their antiviral functions. Thus, Snail and Slug are transcriptionally regulated by RLRs in a similar manner as IFN-β and they in turn promote RLR pathway possibly strengthening the antiviral state in the cell.

scholarly journals Type I interferons act directly on nociceptors to produce pain sensitization: Implications for viral infection-induced pain

2019 ◽  
Author(s):  
Paulino Barragan-Iglesias ◽  
Úrzula Franco-Enzástiga ◽  
Vivekanand Jeevakumar ◽  
Andi Wangzhou ◽  
Vinicio Granados-Soto ◽  
...  
Keyword(s):  
Viral Infection ◽  
Viral Infections ◽  
Mrna Translation ◽  
Type I Interferons ◽  
Poly I:C ◽  
Type I ◽  
Drg Neurons ◽  
Pain Hypersensitivity ◽  
Type I Ifns ◽  
Pain Sensitization

ABSTRACTOne of the first signs of viral infection is body-wide aches and pain. While this type of pain usually subsides, at the extreme, viral infections can induce painful neuropathies that can last for decades. Neither of these types of pain sensitization are well understood. A key part of the response to viral infection is production of interferons (IFNs), which then activate their specific receptors (IFNRs) resulting in downstream activation of cellular signaling and a variety of physiological responses. We sought to understand how type I IFNs (IFN-α and IFN-β) might act directly on nociceptors in the dorsal root ganglion (DRG) to cause pain sensitization. We demonstrate that type I IFNRs are expressed in small/medium DRG neurons and that their activation produces neuronal hyper-excitability and mechanical pain in mice. Type I IFNs stimulate JAK/STAT signaling in DRG neurons but this does not apparently result in PKR-eIF2α activation that normally induces an anti-viral response by limiting mRNA translation. Rather, type I interferons stimulate MNK-mediated eIF4E phosphorylation in DRG neurons to promote pain hypersensitivity. Endogenous release of type I IFNs with the double stranded RNA mimetic poly(I:C) likewise produces pain hypersensitivity that is blunted in mice lacking MNK-eIF4E signaling. Our findings reveal mechanisms through which type I IFNs cause nociceptor sensitization with implications for understanding how viral infections promote pain and can lead to neuropathies.SIGNIFICANCE STATEMENTIt is increasingly understood that pathogens interact with nociceptors to alert organisms to infection as well as to mount early host defenses. While specific mechanisms have been discovered for diverse bacteria and fungal pathogens, mechanisms engaged by viruses have remained elusive. Here we show that type 1 interferons, one of the first mediators produced by viral infection, act directly on nociceptors to produce pain sensitization. Type I interferons act via a specific signaling pathway (MNK-eIF4E signaling) that is known to produce nociceptor sensitization in inflammatory and neuropathic pain conditions. Our work reveals a mechanism through which viral infections cause heightened pain sensitivity

scholarly journals TGF-β and the Smad Signaling Pathway Support Transcriptomic Reprogramming during Epithelial-Mesenchymal Cell Transition

2005 ◽  
Vol 16 (4) ◽  
pp. 1987-2002 ◽  
Author(s):  
Ulrich Valcourt ◽  
Marcin Kowanetz ◽  
Hideki Niimi ◽  
Carl-Henrik Heldin ◽  
Aristidis Moustakas
Keyword(s):  
Target Genes ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Smooth Muscle Actin ◽  
Expression Patterns ◽  
Ectopic Expression ◽  
Dominant Negative ◽  
Type I ◽  
Mesenchymal Transition ◽  
Smad Signaling

Epithelial-mesenchymal transition (EMT) contributes to normal tissue patterning and carcinoma invasiveness. We show that transforming growth factor (TGF)-β/activin members, but not bone morphogenetic protein (BMP) members, can induce EMT in normal human and mouse epithelial cells. EMT correlates with the ability of these ligands to induce growth arrest. Ectopic expression of all type I receptors of the TGF-β superfamily establishes that TGF-β but not BMP pathways can elicit EMT. Ectopic Smad2 or Smad3 together with Smad4 enhanced, whereas dominant-negative forms of Smad2, Smad3, or Smad4, and wild-type inhibitory Smad7, blocked TGF-β–induced EMT. Transcriptomic analysis of EMT kinetics identified novel TGF-β target genes with ligand-specific responses. Using a TGF-β type I receptor that cannot activate Smads nor induce EMT, we found that Smad signaling is critical for regulation of all tested gene targets during EMT. One such gene, Id2, whose expression is repressed by TGF-β1 but induced by BMP-7 is critical for regulation of at least one important myoepithelial marker, α-smooth muscle actin, during EMT. Thus, based on ligand-specific responsiveness and evolutionary conservation of the gene expression patterns, we begin deciphering a genetic network downstream of TGF-β and predict functional links to the control of cell proliferation and EMT.

scholarly journals Activation of an Antiviral Response in Normal but Not Transformed Mouse Cells: a New Determinant of Minute Virus of Mice Oncotropism

2009 ◽  
Vol 84 (1) ◽  
pp. 516-531 ◽  
Author(s):  
Svitlana Grekova ◽  
Rainer Zawatzky ◽  
Rita Hörlein ◽  
Celina Cziepluch ◽  
Michal Mincberg ◽  
...  
Keyword(s):  
Life Cycle ◽  
Viral Infections ◽  
Neutralizing Antibody ◽  
Antiviral Response ◽  
Type I ◽  
Normal Cells ◽  
Minute Virus Of Mice ◽  
Type I Ifns ◽  
Minute Virus ◽  
Innate Antiviral Response

ABSTRACT Parvovirus minute virus of mice (MVMp) is endowed with oncotropic properties so far ascribed only to the dependency of the virus life cycle on cellular factors expressed during S phase and/or modulated by malignant transformation. For other viruses oncotropism relies on their inability to circumvent type I interferon (IFN)-induced innate antiviral mechanisms, the first line of defense triggered by normal cells against viral infections. These agents propagate, therefore, preferentially in transformed/tumor cells, which often lack functional antiviral mechanisms. The present study aimed at investigating whether antiviral processes also contribute to MVMp oncotropism. Our results demonstrate that in contrast to MVMp-permissive transformed mouse A9 fibroblasts, freshly isolated normal counterparts (mouse embryonic fibroblasts [MEFs]) mount, through production and release of type I IFNs upon their infection, an antiviral response against MVMp lytic multiplication. Pretreatment of MEFs with a type I IFN-β-neutralizing antibody, prior to MVMp infection, inhibits the virus-triggered antiviral response and improves the fulfillment of the MVMp life cycle. Our results also show that part of the A9 permissiveness to MVMp relies on the inability to produce type I IFNs upon parvovirus infection, a feature related either to an A9 intrinsic deficiency of this process or to an MVMp-triggered inhibitory mechanism, since stimulation of these cells by exogenous IFN-β strongly inhibits the parvovirus life cycle. Taken together, our results demonstrate for the first time that parvovirus infection triggers an innate antiviral response in normal cells and suggest that the MVMp oncotropism depends at least in part on the failure of infected transformed cells to mount such a response.

scholarly journals Role of the transcriptional regulator SP140 in resistance to bacterial infections via repression of type I interferons

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Daisy X Ji ◽  
Kristen C Witt ◽  
Dmitri I Kotov ◽  
Shally R Margolis ◽  
Alexander Louie ◽  
...  
Keyword(s):  
Legionella Pneumophila ◽  
Bacterial Infections ◽  
Viral Infections ◽  
Negative Regulator ◽  
Type I Interferons ◽  
Type I ◽  
Type I Ifn ◽  
Viral Immunity ◽  
Type I Ifns ◽  
Important Negative Regulator

Type I interferons (IFNs) are essential for anti-viral immunity, but often impair protective immune responses during bacterial infections. An important question is how type I IFNs are strongly induced during viral infections, and yet are appropriately restrained during bacterial infections. The Super susceptibility to tuberculosis 1 (Sst1) locus in mice confers resistance to diverse bacterial infections. Here we provide evidence that Sp140 is a gene encoded within the Sst1 locus that represses type I IFN transcription during bacterial infections. We generated Sp140-/- mice and find they are susceptible to infection by Legionella pneumophila and Mycobacterium tuberculosis. Susceptibility of Sp140-/- mice to bacterial infection was rescued by crosses to mice lacking the type I IFN receptor (Ifnar-/-). Our results implicate Sp140 as an important negative regulator of type I IFNs that is essential for resistance to bacterial infections.

The transmembrane serine protease hepsin suppresses type I interferon induction by cleaving STING

2021 ◽  
Vol 14 (687) ◽  
pp. eabb4752
Author(s):  
Fu Hsin ◽  
Yu-Chen Hsu ◽  
Yu-Fei Tsai ◽  
Shu-Wha Lin ◽  
Helene Minyi Liu
Keyword(s):  
Innate Immunity ◽  
Viral Infections ◽  
Ectopic Expression ◽  
Type I ◽  
Adapter Proteins ◽  
Type I Ifn ◽  
Chronic Viral Infections ◽  
Viral Proteases ◽  
Transmembrane Serine Protease ◽  
Antiviral Innate Immunity

Many viral proteases mediate the evasion of antiviral innate immunity by cleaving adapter proteins in the interferon (IFN) induction pathway. Host proteases are also involved in innate immunity and inflammation. Here, we report that the transmembrane protease hepsin (also known as TMPRSS1), which is predominantly present in hepatocytes, inhibited the induction of type I IFN during viral infections. Knocking out hepsin in mouse embryonic fibroblasts (MEFs) increased the viral infection–induced expression of Ifnb1, an Ifnb1 promoter reporter, and an IFN-sensitive response element promoter reporter. Ectopic expression of hepsin in cultured human hepatocytes and HEK293T cells suppressed the induction of IFNβ during viral infections by reducing the abundance of STING. These effects depended on the protease activity of hepsin. We identified a putative hepsin target site in STING and showed that mutating this site protected STING from hepsin-mediated cleavage. In addition to hepatocytes, several hepsin-producing prostate cancer cell lines showed reduced STING-mediated type I IFN induction and responses. These results reveal a role for hepsin in suppressing STING-mediated type I IFN induction, which may contribute to the vulnerability of hepatocytes to chronic viral infections.

scholarly journals Alpha/Beta Interferon (IFN-α/β)-Independent Induction of IFN-λ1 (Interleukin-29) in Response to Hantaan Virus Infection

2010 ◽  
Vol 84 (18) ◽  
pp. 9140-9148 ◽  
Author(s):  
Malin Stoltz ◽  
Jonas Klingström
Keyword(s):  
Virus Infection ◽  
Signaling Pathways ◽  
Cell Line ◽  
A549 Cells ◽  
Hantaan Virus ◽  
Poly I:C ◽  
Type I ◽  
Type I Ifn ◽  
Type I Ifns ◽  
A Cell

ABSTRACT Type III interferons ([IFNs]IFN-λ and interleukin-28 and -29 [IL-28/29]) are recently recognized cytokines with innate antiviral effects similar to those of type I IFNs (IFN-α/β). Like IFN-α/β, IFN-λ-expression can be induced by viruses, and it is believed that type I and III IFNs are regulated in the same manner. Hantaviruses are weak IFN-α/β inducers and have surprisingly been shown to activate IFN-α/β-independent IFN-stimulated gene (ISG) expression. Here, we show that in Hantaan virus (HTNV)-infected human epithelial A549 cells, induction of IFN-λ1 preceded induction of MxA and IFN-β by 12 and 24 h, respectively, and IFN-α was not induced at all. Furthermore, induction of IFN-λ1 and MxA was observed in HTNV-infected African green monkey epithelial Vero E6 cells, a cell line that cannot produce type I IFNs, clearly showing that HTNV can induce IFN-λ1 and ISGs in the complete absence of IFN-α/β. In HTNV-infected human fibroblast MRC-5 cells, which lack the IFN-λ receptor, induction of MxA coincided in time with IFN-β-induction. UV-inactivated HTNV did not induce any IFNs or MxA in any cell line, showing that activation of IFN-λ1 is dependent on replicating virus. Induction of both IFN-β and IFN-λ1 in A549 cells after poly(I:C)-stimulation was strongly inhibited in HTNV-infected cells, suggesting that HTNV can inhibit signaling pathways used to simultaneously activate types I and III IFNs. In conclusion, we show that HTNV can cause type I IFN-independent IFN-λ1 induction and IFN-λ1-specific ISG induction. Importantly, the results suggest the existence of specific signaling pathways that induce IFN-λ1 without simultaneous type I IFN induction during virus infection.

scholarly journals Getting “Inside” Type I IFNs: Type I IFNs in Intracellular Bacterial Infections

2017 ◽  
Vol 2017 ◽  
pp. 1-17 ◽  
Author(s):  
Deann T. Snyder ◽  
Jodi F. Hedges ◽  
Mark A. Jutila
Keyword(s):  
Host Cell ◽  
Legionella Pneumophila ◽  
Bacterial Infections ◽  
Viral Infections ◽  
Type I Interferons ◽  
Intracellular Bacteria ◽  
Type I ◽  
Type I Ifn ◽  
Type I Ifns ◽  
Serovar Typhimurium

Type I interferons represent a unique and complex group of cytokines, serving many purposes during innate and adaptive immunity. Discovered in the context of viral infections, type I IFNs are now known to have myriad effects in infectious and autoimmune disease settings. Type I IFN signaling during bacterial infections is dependent on many factors including whether the infecting bacterium is intracellular or extracellular, as different signaling pathways are activated. As such, the repercussions of type I IFN induction can positively or negatively impact the disease outcome. This review focuses on type I IFN induction and downstream consequences during infection with the following intracellular bacteria:Chlamydia trachomatis,Listeria monocytogenes,Mycobacterium tuberculosis,Salmonella entericaserovar Typhimurium,Francisella tularensis,Brucella abortus,Legionella pneumophila, andCoxiella burnetii. Intracellular bacterial infections are unique because the bacteria must avoid, circumvent, and even co-opt microbial “sensing” mechanisms in order to reside and replicate within a host cell. Furthermore, life inside a host cell makes intracellular bacteria more difficult to target with antibiotics. Because type I IFNs are important immune effectors, modulating this pathway may improve disease outcomes. But first, it is critical to understand the context-dependent effects of the type I IFN pathway in intracellular bacterial infections.

scholarly journals Type I Interferon Production of Plasmacytoid Dendritic Cells under Control

2021 ◽  
Vol 22 (8) ◽  
pp. 4190
Author(s):  
Dóra Bencze ◽  
Tünde Fekete ◽  
Kitti Pázmándi
Keyword(s):  
Dendritic Cells ◽  
Viral Infections ◽  
Plasmacytoid Dendritic Cells ◽  
Type I Interferons ◽  
Type I ◽  
Type I Ifn ◽  
Tumor Resistance ◽  
Endogenous Factors ◽  
Associated Diseases ◽  
Type I Ifns

One of the most powerful and multifaceted cytokines produced by immune cells are type I interferons (IFNs), the basal secretion of which contributes to the maintenance of immune homeostasis, while their activation-induced production is essential to effective immune responses. Although, each cell is capable of producing type I IFNs, plasmacytoid dendritic cells (pDCs) possess a unique ability to rapidly produce large amounts of them. Importantly, type I IFNs have a prominent role in the pathomechanism of various pDC-associated diseases. Deficiency in type I IFN production increases the risk of more severe viral infections and the development of certain allergic reactions, and supports tumor resistance; nevertheless, its overproduction promotes autoimmune reactions. Therefore, the tight regulation of type I IFN responses of pDCs is essential to maintain an adequate level of immune response without causing adverse effects. Here, our goal was to summarize those endogenous factors that can influence the type I IFN responses of pDCs, and thus might serve as possible therapeutic targets in pDC-associated diseases. Furthermore, we briefly discuss the current therapeutic approaches targeting the pDC-type I IFN axis in viral infections, cancer, autoimmunity, and allergy, together with their limitations defined by the Janus-faced nature of pDC-derived type I IFNs.

scholarly journals Rotavirus Induces Epithelial–Mesenchymal Transition Markers by Transcriptional Suppression of miRNA-29b

2021 ◽  
Vol 12 ◽  
Author(s):  
Urbi Mukhopadhyay ◽  
Anwesha Banerjee ◽  
Mamta Chawla-Sarkar ◽  
Anupam Mukherjee
Keyword(s):  
Viral Infections ◽  
Epithelial Mesenchymal Transition ◽  
Ectopic Expression ◽  
Dependent Manner ◽  
Structural Protein ◽  
Mesenchymal Transition ◽  
Host Interactions ◽  
Cyclin E1 ◽  
Cellular Components

Acute gastroenteritis (AGE) is a serious global health problem and has been known to cause millions of infant deaths every year. Rotavirus (RV), a member of the Reoviridae family, still majorly accounts for the AGE in children below 5 years of age in India and worldwide. The involvement of miRNAs in the pathogenesis of RV has been suggested to be of the proviral as well as the anti-viral nature. miRNAs that promote the RV pathogenesis are capable of targeting the cellular components to evade the host anti-viral strategies. On the other hand, miRNAs with anti-rotaviral properties are themselves incapacitated during the progression of the infection. The exploitation of the epithelial–mesenchymal transition (EMT) as a pro-rotaviral strategy has already been identified. Thus, miRNAs that proficiently target the intermediates of the EMT pathway may serve as anti-viral counterparts in the RV–host interactions. The role of microRNA-29b (miR-29b) in the majority of human cancers has been well demonstrated, but its significance in viral infections is yet to be elaborated. In this study, we have assessed the role of miR-29b in RV-induced EMT and RV replication. Our study on miR-29b provides evidence for the recruitment of RV non-structural protein NSP1 to control the trans-repression of miR-29b in a p53-dependent manner. The trans-repression of miR-29b modulates the EMT pathway by targeting tripartite motif-containing protein 44 (TRIM44) and cyclin E1 (CCNE1). SLUG and SNAIL transcription repressors (downstream of TRIM44 and CCNE1) regulate the expression of E-cadherin, an important marker of the EMT. Also, it is established that ectopic expression of miR-29b not only constrains the EMT pathway but also restricts RV replication. Therefore, miR-29b repression is a crucial event in the RV pathogenesis. Ectopic expression of miR-29b displays potential anti-viral properties against RV propagation.

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