Fig. 2: Protomer organization of HTNV-L.

a Schematic representation of HTNV-L domain structure. b Cartoon representation of HTNV-L protomer with the endonuclease (ENDO), the core, the mid-link, the cap-binding domain (CBD), the lariat, and the domain C-terminal (CTER) respectively colored in forest green, white, beige, orange, red, and brown. The motifs E and F are respectively colored in magenta and blue. c Zoom on the motif E colored in magenta. d Zoom on the motif F colored in blue. The 5′vRNA end binding site is identified with a dotted line. e Zoom on the mid-link, the CTER, and the lariat colored as in a. The Hantavirus-specific mid-link insertion is indicated and colored in light pink. The CBD position is indicated with a dashed-dotted line. The dotted line that links the CTER to the lariat represents the residues of the lariat that are not visible due to flexibility. f Zoom on HTNV-L CBD model predicted by Alphafold and validated by an 8 Å cryo-EM map. The central five-stranded β-sheet and the α-helix that are common to all sNSV CBD is shown in the orange cartoon. The β-hairpin insertion that is likely to be essential for cap binding is shown in dark orange. The tyrosines that are predicted to bind the cap are shown as sticks. The Hantavirus-specific second β-sheet is shown in light yellow.