Table 1. UPR proteins across eukaryotes.
| Protein Family | UPR Role | HS | MM | DM | CE | SC | AT | DD | TG | PF | LI | TB | TC |
| BiP | ER chaperone | 1 | 1 | 1 | 1 | 1 | 3 | 1 | 1 | 1 | 1 | 1 | 1 |
| Ire1 | Signal transducer | 2 | 2 | 2 | 2 | 1 | 2 | 1 | 0 | 0 | 0 | 0 | 0 |
| HAC1/XBP1 | Transcription factor | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Rlg1 | Ligates HAC1 mRNA | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dcr2 | Regulates Ire1 | 0 | 0 | 0 | 0 | 1 | 4 | 1 | 0 | 0 | 0 | 0 | 0 |
| PERK | Signal transducer | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 |
| Eif2α | Attenuates translation | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Atf4 | Transcription factor | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| DnaJC3 | Regulates PERK/Eif2α | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 1 |
| Atf6 | Transcription factor | 2 | 2 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
Table 1 caption: Protein families involved in the unfolded protein response and their respective size in the eukaryotes examined. Numbers in boldface indicate that the protein is not identifiable via standard sequence homology search but was identified either in the literature [10], [11], or by using techniques described in this manuscript.