Glutamine Synthetase Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
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| Attribute | Value |
|---|---|
| Protein Name | Glutamine Synthetase |
| Gene Symbol | GLUL |
| UniProt ID | P15104 |
| PDB Structures | 2OJC, 2QCM, 1F52, 1GQ5 |
| Molecular Weight | 49.2 kDa (monomer), ~492 kDa (decamer) |
| Subcellular Localization | Cytosol |
| Protein Family | Glutamine synthetase family |
Glutamine Synthetase (GS) is a crucial enzyme in nitrogen metabolism that catalyzes the ATP-dependent synthesis of glutamine from glutamate and ammonia.[1] In the brain, GS is primarily expressed in astrocytes and plays essential roles in the glutamate-glutamine cycle, ammonia detoxification, and neuroprotection. It is implicated in various neurodegenerative diseases including Alzheimer's and Parkinson's disease.
| Isoform | Expression | Notes |
|---|---|---|
| GS1 (GLUL) | Brain, liver | Cytosolic |
| GLUL | Eye lens | Lens-specific |
| PDB ID | Description | Resolution |
|---|---|---|
| 2OJC | Bacterial GS | 2.0 Å |
| 1F52 | Mammalian GS | 2.2 Å |
| 2QCM | Complex with ADP | 2.1 Å |
GS catalyzes the formation of glutamine:[2]
Reaction:
Glutamate + NH3 + ATP → Glutamine + ADP + Pi
Steps:
Glutamate-Glutamine Cycle
Ammonia Detoxification
Neuroprotection
| Condition | GS Role |
|---|---|
| Stroke | Decreased after ischemia |
| Trauma | Biomarker for brain injury |
| Hepatic encephalopathy | Impaired ammonia detoxification |
| ALS | Motor neuron vulnerability |
| Strategy | Approach |
|---|---|
| Gene therapy | AAV-GLUL to astrocytes |
| Metabolic support | Enhance glutamine metabolism |
| Neuroprotection | Reduce excitotoxicity |
The study of Glutamine Synthetase Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Last updated: March 2026