Table 1.
Summary of the ubiquitination and ubiquitination like systems
| Modification | Modifier encoding gene | Mature modifier protein | E1 | E2 | E3 | Active protease |
|---|---|---|---|---|---|---|
| Ubiquitination | UBB, UBC, UBA52 and RPS27A | 76 amino acids | 2 (UBA1 and UBA6) | ~ 40 | Over 600 | Dozens (USPs,UCHs,OTUs,MJD,JAMM) |
| Sumoylation | SUMO1-4 | varies from SUMO1-4 | 1 (SAE) | 1 (UBC9) | A dozen | 6 (SENPs) |
| Neddylation | NEDD8 | 76 amino acids | 1 (NAE) | 2 (UBC12 and UBE2F) | Over 600 | 3 (UCHL1, UCHL3 and USP21) |
| Ufmylation | UFM1 | 83 amino acids | 1 (UBA5) | 1 (UFC1) | 1 (UFL1) | 1 (UFSP2) |
| Isgylation | ISG15 | 163 amino acids | 1 (UBE1L) | 1 (UBCH8) | 2 (HERC5 and TRIM25) | 5 (USP18, USP2, USP5, USP13 and USP14) |
| Fatylation | FAT10 | 165 amino acids | 1 (UBA6) | 1 (USE1) | Unknown | Unknown |