Table 1. SUMOylation machinery.
SUMO conjugation proceeds via the action of E1, E2 and E3 enzymes. In addition, SUMO proteins are both matured and removed from substrate proteins via the protease and isopeptidase activities respectively of the SUMO proteases. The known members of the mammalian SUMO machinery are shown alongside those of yeast (S. cerevisiae).
| Protein family | Yeast (S. cerevisiae) | Mammals |
|---|---|---|
| SUMO | Smt3 | SUMO-1 |
| SUMO-2 | ||
| SUMO-3 | ||
| SUMO E1 (activating enzyme) | Aos1 | SAE1 |
| Uba2 | SAE2 | |
| SUMO E2 (conjugating enzyme) | Ubc9 | Ubc9 |
| SUMO E3 (ligase) | Siz1 | PIAS1 |
| Siz2 | PIAS3 | |
| PIASxα | ||
| PIASxβ | ||
| PIASy | ||
| RanBP2 | ||
| Pc2 | ||
| Mms21 | Mms21 | |
| HDAC4 | ||
| HDAC7 | ||
| MUL1 | ||
| Rhes | ||
| TOPORS | ||
| TLS | ||
| TRAF7 | ||
| SUMO proteases (SUMO proteases and isopeptidases) | Ulp1 | SENP-1 |
| Ulp2 | SENP-2 | |
| SENP-3 | ||
| SENP-5 | ||
| SENP-6 | ||
| SENP-7 |