Figure 1.

Apo structure of the SFTSV L protein. (A) Schematic linear representation of the domain structure of the SFTSV L protein. (B) Illustrated representation of two views of the apo-L cryo-EM structure as a ribbon diagram (PDB 6Y6K). Domains are colored as in (A). The magnesium ion in the active site is shown as a sphere. A more detailed view and comparison with the LACV L (PDB 5AMQ) and the influenza virus polymerase complex (PDB 6QCV) are shown in Supplementary Figures S2–S4. (C) Superposition of the 5 Å low-pass filtered cryo-EM map with the SFTSV apo-L structure model. (D) Representation of the polymerase core of the SFTSV L with the conserved motifs A–H as a ribbon diagram. The divalent magnesium ion is shown as a sphere.