SARS-CoV-2 RNA duplex (dsRNA)

SARS-CoV-2 RNA duplex refers to the double-stranded RNA (dsRNA) structures formed during the replication cycle of the SARS-CoV-2 virus, as well as the complex secondary structures like hairpins and stem-loops within its single-stranded genome [6, 10]. As a positive-sense single-stranded RNA virus, SARS-CoV-2 generates dsRNA intermediates during the synthesis of genomic and subgenomic RNAs by the viral RNA-dependent RNA polymerase (RdRp) [6]. These duplexes are essential for viral propagation but also serve as potent pathogen-associated molecular patterns (PAMPs) recognized by host pattern recognition receptors such as MDA5 and TLR3, which trigger the innate immune response [3, 11]. From a therapeutic perspective, these RNA structures are high-value targets; small molecules can be designed to bind specifically to conserved duplex regions to disrupt viral functions, while antisense oligonucleotides and siRNAs utilize duplex formation to direct the degradation of the viral genome [1, 5, 16]. Drugs like Remdesivir and Molnupiravir also interact with the RNA duplex within the replication complex to terminate or mutate the viral sequence [8, 14]. However, targeting these structures faces significant challenges, including the high abundance of host RNA and the dynamic, unstable nature of RNA folding [1].

Other names

SARS-CoV-2 double-stranded RNASARS-CoV-2 dsRNA intermediateSARS-CoV-2 RNA secondary structureSARS-CoV-2 RNA hairpinSARS-CoV-2 replication intermediate

Therapeutic agents target the SARS-CoV-2 RNA duplex through several mechanisms: small molecules bind to conserved secondary structures (like hairpins) to sterically hinder replication or translation [1]; antisense oligonucleotides (ASOs) and siRNAs hybridize with viral RNA to form duplexes that trigger enzymatic degradation via RNase H or the RISC complex [2, 5, 16]; and nucleoside analogs are incorporated into the growing RNA strand, disrupting the stability and elongation of the duplex within the viral replication-transcription complex [8, 14].