Specifically, we demonstrate that DRH-1/RIG-I is required for inducing the IPR in response to Orsay virus infection, but not in response to other triggers like microsporidian infection or proteotoxic stress.
RIG-I (Retinoic acid-inducible gene I) and MDA5 (Melanoma Differentiation-Associated protein 5), collectively known as the RIG-I-like receptors (RLRs), are key protein sensors of the pathogen-associated molecular patterns (PAMPs) in the form of viral double-stranded RNA (dsRNA) motifs to induce expression of type 1 interferons (IFN1) (IFNα and IFNβ) and other pro-inflammatory cytokines during the early stage of viral infection.
Mechanistically, Lnczc3h7a binds to both TRIM25 and activated RIG-I, serving as a molecular scaffold for stabilization of the RIG-I-TRIM25 complex at the early stage of viral infection.
Neuronal transcriptomic responses to Japanese encephalitis virus infection with a special focus on chemokine CXCL11 and pattern recognition receptors RIG-1 and MDA5.
We found that intracellular poly(I·C) transfection to mimic viral infection enhances the RIG-I/MDA5 (melanoma differentiation-associated gene 5)-mediated dimerization of interferon regulatory factor 3 (IRF-3).
These results suggest that PACT plays an important role in potentiating RIG-I function to produce type I IFNs in order to restrict arenavirus replication and that viral NP RNase activity is essential for optimal viral replication by suppressing PACT-induced RIG-I activation.<b>IMPORTANCE</b> We report here a new role of the nucleoproteins of arenaviruses that can block type I IFN production via their specific inhibition of the cellular protein sensors of virus infection (RIG-I and PACT).
Sumoylation of the caspase recruitment domains of MDA5 and RIG-I is also required for their dephosphorylation by PP1 and activation upon viral infection.
A recent study found that the delivery of circRNAs generated <i>in vitro</i> activates RIG-I-mediated innate immune responses and provides protection against viral infection.
RIG-I-like receptors detect viral RNA in infected cells and promote oligomerization of the outer mitochondrial membrane protein MAVS to induce innate immunity to viral infection through type I interferon production.
This is critical for promoting the growth and survival of T lymphocytes as well as the regulation of the RIG-I helicase pathway for type I interferon production in response to viral infections.
Virus infection is sensed in the cytoplasm by retinoic acid-inducible gene I (RIG-I, also known as DDX58), which requires RNA and polyubiquitin binding to induce type I interferon (IFN) and activate cellular innate immunity.
RIG-I-like receptors (RLRs: RIG-I, MDA5 and LGP2) play a major role in the innate immune response against viral infections and detect patterns on viral RNA molecules that are typically absent from host RNA.
Compared with H1N1 virus-induced mediators, H5N1 mediators markedly enhance the cytokine response to PolyIC and to both seasonal and H5N1 virus infection in a RIG-I-dependent manner.
The RIG-I-like receptor (RLR) family of pattern recognition receptors (PRRs) is a group of cytosolic RNA helicase proteins that can identify viral RNA as nonself via binding to pathogen associated molecular patter (PAMP) motifs within RNA ligands that accumulate during virus infection.