The position of SDP residues in the structures of the five Ras superfamily members, and their possible biological and functional implications
| Family PDB chain | Arf 1hurA,B | Ras (Fig. 5) 121pA | Rho 1a2bA | Rab 2folA | Ran 1l2MA |
| Residues in the proximity of the GTP/GDP binding pocket | Ala28, Pro47, Gly69 | Ala11, Val14, Pro34, Thr58, Ala59 | Asp13, Cys16, Pro36 | Asp16, Val19, Leu25, Ser39 | Thr21, Asp18, Ala41, Ala67 |
| Residues involved in protein–protein interactions | Pro47, Phe51, Trp66, Val68, Gly69 | Pro34, Glu37, Leu56, Ala59, Arg68 | Asp13, Cys16, Leu22, Pro36, Phe39, Thr58, Thr60, Ala61, Asp67, Arg70, Arg122 | Val43, Trp62, Ala65, Arg71 | Asp18, Val45, Trp64, Ala67, Gly73, Arg76, Asp91 Lys127 |
| Residues coordinating communication between different lobes | Arg75, Val91, Asp93, Pro131 | Ala65, Val81, Ala83, Ala121 | Asp67, Cys83, Ser85, Arg122 | Arg71, Ala81, Val87, Leu89, Ala126 | Gly73, Met89, Asp91, Lys127 |
| Conserved SDP residues with unknown function | Leu25, Leu34, Trp78, Thr85 | Gly75, Thr20 | Thr77 | Thr64, Thr74 | Val27, Thr66, Ala83 |
| Family PDB chain | Arf 1hurA,B | Ras (Fig. 5) 121pA | Rho 1a2bA | Rab 2folA | Ran 1l2MA |
| Residues in the proximity of the GTP/GDP binding pocket | Ala28, Pro47, Gly69 | Ala11, Val14, Pro34, Thr58, Ala59 | Asp13, Cys16, Pro36 | Asp16, Val19, Leu25, Ser39 | Thr21, Asp18, Ala41, Ala67 |
| Residues involved in protein–protein interactions | Pro47, Phe51, Trp66, Val68, Gly69 | Pro34, Glu37, Leu56, Ala59, Arg68 | Asp13, Cys16, Leu22, Pro36, Phe39, Thr58, Thr60, Ala61, Asp67, Arg70, Arg122 | Val43, Trp62, Ala65, Arg71 | Asp18, Val45, Trp64, Ala67, Gly73, Arg76, Asp91 Lys127 |
| Residues coordinating communication between different lobes | Arg75, Val91, Asp93, Pro131 | Ala65, Val81, Ala83, Ala121 | Asp67, Cys83, Ser85, Arg122 | Arg71, Ala81, Val87, Leu89, Ala126 | Gly73, Met89, Asp91, Lys127 |
| Conserved SDP residues with unknown function | Leu25, Leu34, Trp78, Thr85 | Gly75, Thr20 | Thr77 | Thr64, Thr74 | Val27, Thr66, Ala83 |
Numbers correspond to positions in the PDB structures (see Table S5).