Structural and functional analysis of the Nipah virus polymerase complex

Abstract

Nipah virus (NiV) is a bat-borne, zoonotic RNA virus that is among the most pathogenic viruses known to humans. The NiV polymerase, which mediates viral genome replication and mRNA transcription, is a drug target. However, NiV polymerase structures were previously unavailable. We determined the cryo-EM structure of the NiV polymerase complex, comprising the large protein (L) and its associated co-factor (P), and performed structural, biophysical, and functional analyses of the NiV polymerase. The complex assembles with a long P tetrameric coiled-coil that is capped by a bundle of ⍺-helices that we show are likely dynamic in solution. Highly conserved zinc-binding modules in the capping domain and a large insert in the RdRp palm domain that is short or absent in most other non-segmented negative strand RNA viruses are critical for replication and transcription. Our findings have the potential to aid in the rational development of drugs to combat NiV infection.