FIG 4.

Examples of relatively rare morphotypes observed in populations of WT virions. (A) Central tomographic slice of a WT particle without a core or eccentric condensate; (B) central tomographic slice (left) and corresponding tomo-bubblegram slice (right) of a WT particle containing an eccentric condensate (marked with an arrow in the left panel). The core is a conical one sampled in an oblique section. While the core is not entirely empty, it lacks sufficient internal density to suggest that it contains a vRNP. This interpretation is confirmed by the bubbling being confined to the eccentric condensate. Bar, 50 nm.