Fig. 6: Incubation with 5′vRNA disrupts HTNV-L symmetric oligomers and results in the formation of another type of 5′vRNA-related HTNV-L dimers.

a Mass photometry of 5′vRNA:HTNV-L ratio 10:1 in buffer containing 30 mM HEPES, 250 mM NaCl, and 5 mM TCEP. The molecular weight and the percentage of each species are indicated. b Size-exclusion chromatography and static light scattering (SEC-SLS) of 5′vRNA:HTNV-L ratio 10:1 injected at different concentrations, with one color attributed to each concentration. The elutions were monitored online using static light scattering and differential refractometry. The dotted lines show the chromatograms monitored using differential refractive index measurements. The dotted lines indicate the molecular masses across the elution peaks calculated from static light scattering and refractive index. The numbers indicate the weight-averaged molar mass (kg/mol) of the observed equilibrium between different multimers. The inset shows the weight-average molar mass plotted as a function of concentration. Source data are provided as a Source Data file. c 2D class averages of HTNV-L apo (left) and HTNV-L incubated with 5′vRNA (right). Monomer, symmetric dimer, 5′vRNA-related dimer, and hexamer class averages are shown. The number of particles and the percentage compared to the entire dataset is indicated. d 2D class averages of the 5′vRNA-related dimer (top) and the apo symmetric dimer (bottom). The core of protomer 1 is shown in the same orientation in both 2D classes and is surrounded by a white solid line (right). Protomers 2 adopt a different position in both dimers and the core of protomer 2 is surrounded by a short dotted line (right). e For the 5′vRNA-related dimer (top), the extra densities that may correspond to positions of the endonuclease (ENDO) and C-terminal regions are indicated with white elongated dotted lines. For the apo dimer (bottom), a projection of the structure in the 2D class orientation is shown with the cores colored in white and gray, the ENDO in green, and the C-terminal regions in beige and orange. The ENDO/C-terminal regions of protomer 1 are surrounded by a white solid line, equivalent regions of protomer 2 by short dotted lines.