Structural analysis of 3’UTRs in insect flaviviruses reveals novel determinants of sfRNA biogenesis and provides new insights into flavivirus evolution

Abstract

Subgenomic flaviviral RNAs (sfRNAs) are produced by pathogenic flaviviruses to counteract the host antiviral response. sfRNAs are products of incomplete degradation of viral RNA by the host exoribonuclease XRN1 which stalls on XRN1-resistant structural elements (xrRNAs) in the 3‟UTR. Here, Slonchak et al. identify xrRNAs for mosquito-specific flaviviruses, characterize their ability to stall XRN1 and produce sfRNAs, and apply structure-based phylogenetic analysis to provide evidence for evolutionary selection of these elements.