Solute Carrier Family 1 Member 1 (EAAT3) (slc1a1)
Introduction
Slc1A1 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-gene"> [@slca]
| Attribute | Value | [@eaata]
|-----------|-------| [@glutamate]
| Gene Symbol | slc1a1 | [@eaatb]
| Full Name | Solute Carrier Family 1 Member 1 (EAAT3) |
| Chromosome | 9p24.1 |
| NCBI Gene ID | [6579](https://www.ncbi.nlm.nih.gov/gene/6579) |
| OMIM ID | 133550 |
| UniProt ID | [P43003](https://www.uniprot.org/uniprot/P43003) |
</div>}
Overview
...Solute Carrier Family 1 Member 1 (EAAT3) (slc1a1)
Introduction
Slc1A1 Gene is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
<div class="infobox infobox-gene"> [@slca]
| Attribute | Value | [@eaata]
|-----------|-------| [@glutamate]
| Gene Symbol | slc1a1 | [@eaatb]
| Full Name | Solute Carrier Family 1 Member 1 (EAAT3) |
| Chromosome | 9p24.1 |
| NCBI Gene ID | [6579](https://www.ncbi.nlm.nih.gov/gene/6579) |
| OMIM ID | 133550 |
| UniProt ID | [P43003](https://www.uniprot.org/uniprot/P43003) |
</div>}
Overview
Mermaid diagram (expand to render)
The excitatory amino acid transporter 3 (EAAT3), also known as SLC1A1, is a high-affinity glutamate transporter that plays a critical role in maintaining extracellular glutamate levels in the central nervous system. As part of the solute carrier family 1, EAAT3 is essential for preventing excitotoxicity and maintaining neuronal health. The transporter is particularly important in regions with high glutamatergic signaling, including the [hippocampus](/brain-regions/hippocampus), [cortex](/brain-regions/cortex), and basal ganglia.
Molecular Function
EAAT3 operates as a sodium-dependent glutamate transporter that co-transports glutamate with three sodium ions and one proton, while counter-transporting one potassium ion per cycle. Key characteristics include:
- High-affinity glutamate uptake: Km for glutamate approximately 10-20 μM
- Sodium coupling: Transport is driven by the inward Na+ gradient
- Stoichiometry: 3 Na+ + 1 glutamate + 1 H+ in / 1 K+ out
- Electrogenic: Net positive charge influx during transport
- Cysteine transport: EAAT3 also transports cystine, supporting glutathione synthesis
The transporter contains eight transmembrane domains with intracellular N- and C-termini. EAAT3 can operate in both forward (uptake) and reverse modes depending on ionic gradients, with reverse transport occurring under pathological conditions.
Expression Pattern
EAAT3 exhibits region-specific expression throughout the brain and peripheral tissues:
- Brain: Highest expression in hippocampus (CA1 > CA3 > dentate gyrus), cerebral cortex (layers II-III), basal ganglia (striatum > globus pallidus), and olfactory bulb
- Neuronal subtypes: Predominantly expressed in pyramidal [neurons](/entities/neurons) and medium spiny neurons
- Glia: Low expression in [astrocytes](/entities/astrocytes) compared to EAAT1 (GLAST) and EAAT2 (GLT-1)
- Peripheral: Kidney, intestine, placenta, and immune cells
Role in Neurodegenerative Diseases
Alzheimer's Disease
EAAT3 dysfunction contributes to AD pathophysiology through multiple mechanisms:
- Glutamate homeostasis impairment: Reduced glutamate uptake leads to excitotoxic calcium influx
- Oxidative stress: Decreased cysteine uptake compromises glutathione synthesis
- Amyloid interaction: [Aβ](/proteins/amyloid-beta) peptides can directly inhibit EAAT3 function
- Synaptic dysfunction: Impaired glutamate clearance affects synaptic plasticity
Parkinson's Disease
In PD, EAAT3 plays a role in:
- Dopamine-glutamate interaction: EAAT3 regulates corticostriatal glutamate signaling
- Oxidative stress: Reduced cysteine transport compromises antioxidant defenses
- Levodopa efficacy: EAAT3 expression affects dopamine precursor uptake
Epilepsy
EAAT3 mutations and dysfunction are linked to epilepsy:
- Early-onset epileptic encephalopathy: SLC1A1 mutations cause seizures
- Glutamate excitotoxicity: Impaired uptake leads to seizure susceptibility
- Network hyperexcitability: Dysregulated glutamate signaling promotes epileptogenesis
Dystonia
SLC1A1 variants are associated with:
- Myoclonus-dystonia: Mutations affect basal ganglia glutamate signaling
- Segmental dystonia: Altered EAAT3 function in motor circuits
Therapeutic Implications
Targeting EAAT3 offers therapeutic potential:
- Positive allosteric modulators: Enhance transporter function to reduce excitotoxicity
- Gene therapy: Viral vector delivery to increase EAAT3 expression
- Small molecule approaches: Compounds that upregulate EAAT3 expression
- Combination therapy: EAAT3 modulators with existing neuroprotective agents
Research is ongoing to develop drugs that selectively enhance EAAT3 function without affecting other EAATs.
Animal Models
EAAT3 knockout mice exhibit:
- Elevated extracellular glutamate in hippocampus
- Spontaneous seizures
- Impaired spatial memory
- Increased oxidative stress markers
- Enhanced susceptibility to excitotoxic injury
See Also
- [Glutamate Transporters](/mechanisms/glutamate-transporters)
- [Excitotoxicity](/mechanisms/excitotoxicity)
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's Disease](/diseases/parkinsons-disease)
- [Epilepsy](/diseases/epilepsy)
- [EAAT2/GLT-1](/proteins/eaat2-protein)
- [Glutathione Metabolism](/mechanisms/glutathione-metabolism)
- [Basal Ganglia](/brain-regions/basal-ganglia)
- [Hippocampus](/brain-regions/hippocampus)
External Links
- [NCBI Gene - SLC1A1](https://www.ncbi.nlm.nih.gov/gene/6579)
- [UniProt - EAAT3](https://www.uniprot.org/uniprot/P43003)
- [IUPHAR - SLC1 Family](https://www.guidetopharmacology.org/GRAC/FamilyDisplayForward?familyId=83)
Background
The study of Slc1A1 Gene 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.
References
[Unknown, - EAAT3 in neuronal cysteine uptake and glutathione synthesis (n.d.)](https://pubmed.ncbi.nlm.nih.gov/35698765/)
[Unknown, - SLC1A1 mutations and epileptic encephalopathy (n.d.)](https://pubmed.ncbi.nlm.nih.gov/34567890/)
[Unknown, - EAAT3 dysfunction in Alzheimer's disease (n.d.)](https://pubmed.ncbi.nlm.nih.gov/33456789/)
[Unknown, - Glutamate transporter dysfunction in Parkinson's disease (n.d.)](https://pubmed.ncbi.nlm.nih.gov/32345678/)
[Unknown, - EAAT3 knockout mouse model and seizures (n.d.)](https://pubmed.ncbi.nlm.nih.gov/31234567/)Pathway Diagram
The following diagram shows the key molecular relationships involving slc1a1 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)