Table 1. Hsp90 Co-chaperones.
| Co-chaperone1 | Essential2 | Function |
|---|---|---|
| Sti1 (Hop1) | Non-essential | Binds to the N- and C-terminal of Hsp90, preventing the N-terminal dimerization reaction required for ATP hydrolysis140 |
| Aha1 (Aha1) | Non-essential | Enhances Hsp90 ATPase activity72,76 |
| Cdc37 (p50) | Essential | Links Hsp90 to client protein kinases70 |
| Pih1 | Non-essential | Interacts with Hsp90 and DNA helicases78 |
| Cns1 (TTC4) | Essential | Interacts with Hsp90 C-terminus141 |
| Tah1 | Non-essential | Interacts with Hsp90 C-terminus and DNA helicases78 |
| Sgt1 (Sgt1) | Essential | Binds non-ATP bound forms of Hsp90, linking Hsp90 to client proteins81 |
| Sba1 (p23) | Non-essential | Stabilises the ATP bound state of Hsp9077 |
| Cpr6/7 (Cyp40) | Non-essential | Enhances Hsp90 ATPase activity82 |
1
(Name of mammalian orthologue)
2
Essential for viability in S. cerevisiae