Viral double-stranded RNA (dsRNA) (dsRNA)

Viral double-stranded RNA (dsRNA) is a critical molecular signature of viral infection, produced as a replication intermediate by RNA viruses or through bidirectional transcription in DNA viruses (Source: PubMed, PMID: 28288100). In mammalian cells, long dsRNA helices act as potent pathogen-associated molecular patterns (PAMPs) that are typically absent under normal physiological conditions (Source: NIH). These structures are sensed by specialized host receptors, primarily Melanoma Differentiation-Associated protein 5 (MDA5) in the cytoplasm and Toll-like receptor 3 (TLR3) in endosomes (Source: UniProt, Q9BYX4). Upon binding, these receptors trigger signaling cascades involving IRF3 and NF-κB, leading to the robust production of Type I interferons and the establishment of an antiviral state (Source: StatPearls). Additionally, dsRNA directly activates the pro-apoptotic protein kinase R (PKR) and the 2-5-oligoadenylate synthetase (OAS)/RNase L pathway to halt viral protein synthesis and degrade viral genomes (Source: Wikipedia). Therapeutic strategies often utilize synthetic dsRNA analogs like Poly(I:C) or Rintatolimod to bolster the innate immune response against viruses and tumors, though careful dosing is required to avoid excessive systemic inflammation (Source: ClinicalTrials.gov).

Other names

Double-stranded RNAViral dsRNAvdsRNALong dsRNAPathogen-associated molecular pattern RNA

Binding and activation of pattern recognition receptors (PRRs) such as MDA5 and TLR3, leading to the activation of IRF3 and NF-κB transcription factors and subsequent induction of Type I interferons (Source: PubMed, PMID: 17475884). It also directly activates Protein Kinase R (PKR), which phosphorylates eIF2α to inhibit protein synthesis, and the OAS/RNase L pathway, which degrades viral and cellular RNA (Source: NIH).