| First Author | Krzysiak TC | Year | 2018 |
| Journal | Mol Cell | Volume | 72 |
| Issue | 6 | Pages | 985-998.e7 |
| PubMed ID | 30415949 | Mgi Jnum | J:268829 |
| Mgi Id | MGI:6270035 | Doi | 10.1016/j.molcel.2018.10.007 |
| Citation | Krzysiak TC, et al. (2018) An Insulin-Responsive Sensor in the SIRT1 Disordered Region Binds DBC1 and PACS-2 to Control Enzyme Activity. Mol Cell 72(6):985-998.e7 |
| abstractText | Current models of SIRT1 enzymatic regulation primarily consider the effects of fluctuating levels of its co-substrate NAD(+), which binds to the stably folded catalytic domain. By contrast, the roles of the sizeable disordered N- and C-terminal regions of SIRT1 are largely unexplored. Here we identify an insulin-responsive sensor in the SIRT1 N-terminal region (NTR), comprising an acidic cluster (AC) and a 3-helix bundle (3HB), controlling deacetylase activity. The allosteric assistor DBC1 removes a distal N-terminal shield from the 3-helix bundle, permitting PACS-2 to engage the acidic cluster and the transiently exposed helix 3 of the 3-helix bundle, disrupting its structure and inhibiting catalysis. The SIRT1 activator (STAC) SRT1720 binds and stabilizes the 3-helix bundle, protecting SIRT1 from inhibition by PACS-2. Identification of the SIRT1 insulin-responsive sensor and its engagement by the DBC1 and PACS-2 regulatory hub provides important insight into the roles of disordered regions in enzyme regulation and the mode by which STACs promote metabolic fitness. |
