Size and structure of the sequence space of repeat proteins
Fig 2
Contributions of within-repeat interactions (S1 − Sir green), repeat-repeat interactions (Sir,λ − Sfull, purple), and phylogenic bias between consecutive repeats (Sir − Sir,λ, blue), to the entropy reduction from an independent-site model.
All three contributions are comparable, but with a larger effect of within-repeat interactions and phylogenic bias in TPR. The fourth bar (orange) quantifies the redundancy between two constraints with overlapping scopes: the constraint on consecutive-repeat similary, and the constraint on repeat-repeat correlations. This redundancy is naturally measured within information theory by the difference of impact (i.e. entropy reduction) of a constraint depending on whether or not the other constraint is already enforced.