Crystal structure of N-terminal degron-truncated human glutamine synthetase.
Chek, M.F., Kim, S.Y., Mori, T., Kojima, H., Hakoshima, T.(2021) Acta Crystallogr F Struct Biol Commun 77: 427-434
- PubMed: 34726182 
- DOI: https://doi.org/10.1107/S2053230X21010748
- Primary Citation of Related Structures:  
7EVT - PubMed Abstract: 
Glutamine synthetase (GS) is a decameric enzyme that plays a key role in nitrogen metabolism. Acetylation of the N-terminal degron (N-degron) of GS is essential for ubiquitylation and subsequent GS degradation. The full-length GS structure showed that the N-degron is buried inside the GS decamer and is inaccessible to the acetyltransferase. The structure of N-degron-truncated GS reported here reveals that the N-degron is not essential for GS decamer formation. It is also shown that the N-degron can be exposed to a solvent region through a series of conformational adjustments upon ligand binding. In summary, this study elucidated the dynamic movement of the N-degron and the possible effect of glutamine in enhancing the acetylation process.
Organizational Affiliation: 
Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.