Mumps virus RNA-dependent RNA polymerase (MuV RdRp)

The Mumps virus RNA-dependent RNA polymerase (RdRp), primarily encoded by the Large (L) protein, is the central catalytic component of the viral replication machinery [1]. It operates within a complex with the viral phosphoprotein (P) to execute two distinct processes: the transcription of viral genes into messenger RNAs and the replication of the negative-sense genomic RNA [2]. The L protein is a multifunctional enzyme that includes domains for RNA polymerization, as well as the enzymatic activities required for 5' capping (guanylyltransferase and methyltransferase) and 3' polyadenylation of viral transcripts [1,3]. Because the mumps virus causes significant morbidity, including parotitis, orchitis, and aseptic meningitis, the RdRp is a critical target for therapeutic intervention [4]. Since humans lack a direct homolog to this viral enzyme, inhibitors can achieve high selectivity, minimizing damage to host cells [5]. While the mumps vaccine is highly effective, the development of RdRp inhibitors like Favipiravir remains vital for treating severe cases and managing outbreaks in populations with waning immunity [6]. Sources: [1] UniProt Consortium. UniProtKB - P19123 (L_MUMPV). [2] Whelan, S. P., et al. (2004). Transcription and replication of nonsegmented negative-strand RNA viruses. Current Topics in Microbiology and Immunology. [3] Morin, B., et al. (2013). The polymerase of negative-strand RNA viruses. Antiviral Research. [4] Hviid, A., et al. (2008). Mumps. The Lancet. [5] Furuta, Y., et al. (2013). Favipiravir (T-705), a novel viral RNA polymerase inhibitor. Antiviral Research. [6] de Vries, R. D., et al. (2021). Mumps virus: an update on the epidemiology, pathogenesis, and potential antivirals. Journal of Clinical Virology.

Other names

Large proteinL proteinRNA-directed RNA polymeraseMuV LMumps virus L protein

Inhibition of viral RNA synthesis through competitive inhibition of the polymerase active site or premature chain termination during RNA polymerization.