Distribution of local folding free energies over the residues of Gαi or Gαt. Free energies are given as ln(kf) in the GDP or GTPγS bound forms of the proteins as indicated. Secondary structure elements are indicated as strips next to the x-axis (black for helices, grey for β-sheets) and named according to the convention given in figure 1. Known switch regions are also shown as grey strips numbered form I to IV on top of each picture. The two sequences are aligned and Swiss Prot residue numbering for Gαi is used in both cases.