Figure 3

Simplified, two dimensional clade diagram of hyperdimensional viral RNA protein sequence-space. Because of RNA_pol (P) infidelity and Müller's ratchet, mutations () are introduced into each RNA template synthesized, and progressively accumulate, resulting in an RNA quasispecies with sequence progressively divergent from consensus sequence. Translation results in a spectrum of proteins (, , , etc.) with properties that also vary progressively from wild-type sequence () to highly variant proteins (, , etc.). Some RNAs will be so abnormal that translation or replication fails or is truncated (), while others will code for grossly defective proteins ( , etc.).