Influenza: An RNA-synthesizing machine.

Abstract

Crystal structures of the complete RNA polymerases from influenza A and B viruses provide insight into how these enzymes initiate RNA synthesis, and reveal targets for antiviral drug design. See Articles p.355 & p.361 Stephen Cusack and colleagues have solved the crystal structure of the complete influenza polymerase, comprising subunits PA, PB1 and PB2, bound to its viral RNA promoter. In the first of two papers they present the structure of the polymerase from a bat-specific influenza A virus, which is evolutionarily close to human/avian influenza A strains. The second paper presents the structure of the polymerase from a human isolate of influenza B. Together, the structures provide a wealth of information about how the influenza polymerase functions and how the different subunits interact with each other.