Summary of predicted interactions between lethal and conditional Smt3 amino acid substitutions and the E1 activating enzyme, E2 conjugating enzyme, Ulp1/2 isopeptidases (only structures of Ulp1 have been formally determined) and SIMs of downstream interacting proteins.

Substitutions predicted to be destabilizing based on Rosetta analysis are indicated in bold (REU (Rosetta energy unit) > 2.0) or underlined (REU between 1.0–2.0) text. **Predicted interactions are based on published, structure-based analysis of human or yeast protein complexes, as summarized in the final row.