biostudies-literatureChek MFTakeda Science FoundationJapan Agency for Medical Research and DevelopmentMinistry of Education, Culture, Sports, Science and Technology427-434https://www.ebi.ac.uk/biostudies/studies/S-EPMC8561813biostudies-literatureUnknown77(Pt 11)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.Acta crystallographica. Section F, Structural biology communicationsCrystal structure of N-terminal degron-truncated human glutamine synthetase.PMC8561813JP17gm1010008Kim SYChek MFKojima HMori THakoshima TfalseCrystal structure of N-terminal degron-truncated human glutamine synthetase.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.2021-01-01T00:00:00Z2021 Nov2026-05-31T16:01:47.755Z2025-02-19T01:27:31.549ZS-EPMC85618133472618210.1107/s2053230x2101074810.1107/S2053230X21010748