Extended Data Fig. 4 |. Interactions among Tim17, Tim23, and Tim44.

a, Side view showing the positions of glycine in Tim17 (green Cα-trace) and Tim23 (cyan Cα-trace). Positions of all glycine residues are shown as spheres (Cα atoms) with residue numbers. Red spheres indicate positions in which mutation to a non-glycine amino acid would cause steric clashes. Gray spheres indicate positions in which mutation may not cause steric clashes. b and c, As in a, but viewing down the planes indicated by arrows in panel a from the IMS. d, Mapping of amino acid positions that have been shown to produce an inter-subunit photocrosslinking adduct with p-benzoyl-L-phenylalanine (Bpa). Tim17 (green), Tim23 (cyan), and Tim44 (magenta) are shown in a cylindrical cartoon representation. Green and cyan spheres are positions in Tim44 that crosslink to Tim17 and Tim23, respectively. Magenta spheres are positions in Tim17 and Tim23 that crosslink to Tim44. See panel e for details. e, Summary of previously reported inter-subunit photocrosslinking results. The minimal distance is between the position (Cα for Tim17-G106 and Cβ atom for all other positions) into which Bpa was incorporated and the crosslinked subunit (atom is specified).