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07/03/2020

What is RIG-I signaling?

What is RIG-I signaling?

RIG-I functions as a pattern recognition receptor and PRR’s are the molecules that start the notification process. PRRs recognize specific Pathogen-Associated Molecular Patterns (PAMP). Once the PAMP is recognized, it can then lead to a signaling cascade producing an inflammatory response or an interferon response.

What do rig like receptors do?

RIG-like receptors (retinoic acid-inducible gene-I-like receptors, RLRs) are a type of intracellular pattern recognition receptor involved in the recognition of viruses by the innate immune system. The RLR receptors provide frontline defence against viral infections in most tissues.

What does Rig 1 detect?

RIG-I (a.k.a. DDX58) and MDA5 (a.k.a. IFIH1) are major sensors of RNA viral infection, recognizing double-stranded RNA, 5′-triphosphorylated RNAs, and other specific nucleic acid structures as pathogen-associated molecular patterns (PAMPs) that signal the presence of virus.

Where are rig receptors located?

cytosol
RLRs are expressed in most cell types and are primarily located in the cytosol, although recent studies showed that RIG-I may also localize to the cell nucleus27,28.

What activates RIG?

RIG-I is a pattern recognition receptor and recognizes cytoplasmic viral double-stranded RNA (dsRNA). Influenza A virus, hepatitis C virus, and several other pathogenic viruses are mainly recognized by RIG-I, resulting in the activation of the innate immune responses.

What are the structures that RIG-I and MDA5 recognize?

The RLR signaling pathway is shown. RIG-I and MDA5 recognize a complementary set of cytosolic viral dsRNA ligands. Their activation is tightly regulated by phosphorylation, ubiquitination, and host proteins such as LGP2. RIG-I and MDA5 signal to MAVS, which initiates the production of interferon signaling.

What do RLRs do?

RLRs are the primary means by which cytoplasmic viral double-stranded RNA (dsRNA) is detected. RLR signaling ultimately leads to the production of type-1 IFN and pro-inflammatory cytokines, thereby inhibiting viral replication and promoting acquired immunity.

What do RLRs recognize?

RLRs belong to the RNA helicases family that specifically detects RNA species derived from viruses in the cytoplasm (Table 1) and coordinate anti-viral programs via type I IFN induction (10).

Where are RLRs found?

Structure and ligands of the RLR family This sensing occurs in the cytoplasm of both immune and non-immune cells and is independent of the TLRs that can detect the RNA species present within endosome (68).

What cells express rig1?

RIG-I and MDA5 are expressed in all cell types (60), but are most well-known for their functions inside innate immune cells, such as macrophages, neutrophils, and dendritic cells, as well as in other cells like mucosal epithelial cells. They are classified as ATP-dependent DExD/H box RNA helicases.

Which is part of the signaling pathway does RIG-I activate?

RIG-I, research suggests that this modification is essential for the proper activation of downstream signaling pathways. Following oligomerization, RIG-I and MDA5 activate IPS-1/MAVS on the mitochondrial membrane.

What is the role of RIG I like receptors?

The RIG-I-like receptors (RLRs) are a family of cytosolic pattern recognition receptors that are essential for detecting viral RNA and initiating the innate immune response.

How does RIG I trigger the autophagic process?

In the present study, we examined whether the RIG-I signaling pathway, which detects viral infections by recognizing viral RNA, triggers the autophagic process. The introduction of polyI:C into the cytoplasm, or Sendai virus infection, significantly induced autophagy in normal cells but not in RIG-I-deficient cells.

What is the role of RIG-I in the immune system?

RIG-I (retinoic acid-inducible gene I) is an RNA helicase that triggers the cellular innate interferon (IFN) immune response upon detection of viral double-stranded RNA (Yoneyama et al., 2004). From: Advances in Applied Microbiology, 2011