Structures of flavivirus RNA promoters suggest two binding modes with NS5 polymerase

Abstract

Flaviviruses use a ~70 nucleotide stem-loop structure called stem-loop A (SLA) at the 5’ end of the RNA genome as a promoter for RNA synthesis by the viral polymerase NS5. Here the authors describe the structures of dengue and Zika virus SLAs, identify the SLA-binding site on NS5, and propose models for how NS5 recognizes the RNA promoter.