Interplay between Chaperones and Protein Disorder Promotes the Evolution of Protein Networks
Figure 1
An extended model of protein evolution incorporates the stability effect of mutations.
A Conventionally, protein evolution is described by the rates of non-synonymous substitutions dN, and synonymous substitutions dS, and their rate ratio ω = dN/dS. To accommodate the disparate effect of different amino acid changes on protein stability, the rate of non-synonymous substitutions dN is split into the rates of conservative substitutions dC, and non-conservative substitutions dNC. B Predicted stability effects of conservative (C) and non-conservative (NC) mutations. NC mutations are more likely destabilizing than C mutations. C NC mutations are much more likely highly destabilizing (ΔΔG<−2 kcal/mol) than C mutations. D The evolutionary rate dNC is on average lower than dC and dN, suggesting that NC substitutions are generally under stronger purifying selection. E The evolutionary rate ratios ω = dN/dS and λ = dNC/dC are not correlated, thus independent parameters that contribute orthogonal insights.