Middle East respiratory syndrome coronavirus RNA-dependent RNA polymerase (RdRp) (RdRp)

The Middle East respiratory syndrome coronavirus (MERS-CoV) RNA-dependent RNA polymerase (RdRp), also known as non-structural protein 12 (nsp12), is the primary enzyme responsible for the replication and transcription of the viral RNA genome [1, 2]. It functions as the catalytic core of the replicase-transcriptase complex, typically requiring the co-factors nsp7 and nsp8 to achieve optimal activity and processivity [7, 16]. RdRp catalyzes the synthesis of both genomic and subgenomic RNA by utilizing the positive-sense viral RNA as a template [9, 16]. Due to its essential role in the viral life cycle and its high degree of conservation across the Coronaviridae family, RdRp is a major target for broad-spectrum antiviral drug development [3, 5]. Therapeutic agents such as remdesivir and molnupiravir target this enzyme by acting as nucleotide analogs that cause delayed chain termination or lethal mutagenesis, respectively [4, 8, 15]. Because RdRp lacks a direct human homolog, it offers a high degree of selectivity for antiviral therapy, minimizing potential off-target effects on host cell proteins [5, 9]. Monitoring viral load through the detection of RdRp-specific RNA sequences via qRT-PCR serves as a critical biomarker for diagnosing infection and monitoring treatment efficacy [14, 17].

Other names

nsp12non-structural protein 12MERS-CoV RdRpMERS-CoV nsp12RNA-directed RNA polymerase

Inhibition of viral RNA synthesis through delayed RNA chain termination, competitive inhibition of nucleotide incorporation, or induction of lethal mutagenesis [4, 8, 15].