Figure 6: Genome packaging sequence or NP code mutations disrupt coordinated packaging of eight influenza genome segments into viral particles.
From: A conserved influenza A virus nucleoprotein code controls specific viral genome packaging
Wt NP code and vRNA packaging sequences ensure coordinated incorporation of the eight different genome segments into influenza A virus particles, resulting in an equal ratio of the individual viral genome segments (left panel). As indicated by dashed lines, packaging could be coordinated by various interactions between segment-specific vRNPs, including interactions between vRNA packaging sequences, between vRNA packaging sequences in one vRNP and amino acids of the NP code (indicated in yellow) in a second vRNP, and direct interactions of the NP code amino acids. Mutations in the NP code and/or vRNA packaging sequence result in the loss of coordinated packaging of the eight different genome segments into viral particles and a disproportional ratio of the viral segments (right panel). Loss of coordinated packaging might be caused by impaired interactions between vRNPs mediated by amino acids of the NP code and/or nucleotides of the RNA packaging sequences.
