Crystal 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.

Source: Acta Crystallographica Section F - October 29, 2021 Category: Biochemistry Authors: Chek, M.F. Kim, S.-Y. Mori, T. Kojima, H. Hakoshima, T. Tags: glutamine synthetase N-terminal degron crystal structure research communications Source Type: research