Chikungunya virus non-structural protein 4 (nsP4)

Chikungunya virus non-structural protein 4 (nsP4) is the primary enzymatic component of the viral replication complex, serving as the RNA-dependent RNA polymerase (RdRp) (UniProt: P08411). It plays a critical role in the Chikungunya virus (CHIKV) life cycle by catalyzing the synthesis of negative-strand RNA intermediates and subsequent positive-strand genomic and subgenomic RNAs (PMID: 33444813). The protein is characterized by highly conserved motifs, including the catalytic GDD motif, which are essential for its nucleotidyltransferase activity. As an essential enzyme for viral propagation that lacks a human ortholog, nsP4 is considered a high-priority target for antiviral drug development. Inhibition of nsP4 typically involves nucleoside or nucleotide analogs that act as chain terminators or induce lethal mutagenesis within the viral population (PMID: 24501066). Drugs like Favipiravir and Ribavirin have shown efficacy in inhibiting nsP4 activity in various experimental models (PMID: 21148258). Targeting this protein aims to reduce viral titers and alleviate the severe joint pain and fever associated with Chikungunya infection. However, the potential for the virus to develop resistance mutations within the nsP4 gene remains a significant therapeutic challenge (PMID: 30564543).

Other names

RNA-dependent RNA polymeraseRdRpCHIKV RdRpNon-structural protein 4P1234 polyprotein

Inhibition of viral RNA-dependent RNA polymerase activity, leading to premature chain termination or lethal mutagenesis of the viral genome (PMID: 24501066).