Figure 6.

Sequence features that distinguish the canonical and non-canonical PBC containing sequences. (a) A contrast hierarchical alignment (see Figure 2 legend) showing residues (indicated by black dots above alignment) that distinguish the canonical PBC containing sequences from the non-canonical ones. Biochemically similar residues are colored similarly with the intensity of the highlighting proportional to how strikingly foreground residues contrast with background residues. (b) The allosteric link between the PBC and β2-β3 loop is shown using the cAMP bound and cAMP-free structures of the PKA regulatory subunit.