RNA-directed RNA polymerase (RdRp) (RdRp)

RNA-directed RNA polymerase (RdRp), specifically the non-structural protein 12 (nsp12) in coronaviruses, is the central enzyme of the viral replication and transcription machinery (UniProt: P0DTD1). It catalyzes the synthesis of the viral RNA genome and subgenomic mRNAs, making it essential for the production of new virions within a host cell (Nature: 10.1038/s41586-020-2168-x). RdRp typically functions as part of a larger complex involving accessory proteins like nsp7 and nsp8, which enhance its binding and processivity (PubMed: 32457148). Given its vital role and the absence of a direct human ortholog, RdRp is a premier target for antiviral drugs such as remdesivir and molnupiravir (NIH: StatPearls - Antiviral Medications). These therapeutic agents are often nucleoside analogs that, once phosphorylated, compete with natural nucleotides for incorporation into the growing RNA strand. This incorporation results in either the termination of RNA synthesis or the accumulation of deleterious mutations, effectively halting viral spread. Clinical monitoring of RdRp-targeted therapies often relies on assessing viral load reductions in patient samples.

Other names

RNA-dependent RNA polymerasensp12non-structural protein 12replicasePol

Nucleoside analog inhibition leading to delayed chain termination or lethal mutagenesis through the induction of transition mutations during viral RNA synthesis.