SLC19A3 Gene - Thiamine Transporter 2
Solute Carrier Family 19 Member 3: Role in Thiamine Transport and Neurological Disorders
Gene Information Card
| Symbol | SLC19A3 |
|---|---|
| Full Name | Solute Carrier Family 19 Member 3 |
| Gene Type | Protein coding |
| Chromosomal Location | 2q36.3 |
| NCBI Gene ID | 80704 ncbi.nlm.nih.gov/gene/80704 |
| Ensembl ID | ENSG00000135924 |
| UniProt ID | Q9BZV2 |
| OMIM ID | 606152 |
| HGNC ID | 10966 |
| Aliases | THTR2, THMD2, BBGD |
Description
SLC19A3 encodes the thiamine transporter 2 (THTR2), a transmembrane protein responsible for the cellular uptake of thiamine (vitamin B1). Thiamine is essential for carbohydrate metabolism and neural function. Mutations in SLC19A3 cause thiamine metabolism dysfunction syndrome 2 (THMD2), also known as biotin-responsive basal ganglia disease (BBGD), a rare autosomal recessive neurological disorder. The gene is primarily expressed in the brain, kidney, and liver.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Biotin-responsive basal ganglia disease (BBGD) | Loss-of-function mutations impair thiamine transport into brain cells, leading to basal ganglia necrosis and neurological symptoms. | OMIM #607483; ClinVar |
| Thiamine metabolism dysfunction syndrome 2 (THMD2) | Defective thiamine uptake due to SLC19A3 mutations causes metabolic crisis, encephalopathy, and dystonia. | OMIM #607483; NCBI Gene |
| Wernicke-like encephalopathy | Severe thiamine deficiency secondary to SLC19A3 mutations mimics Wernicke encephalopathy. | Case reports; ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 5.1 | Low |
| Kidney | 12.3 | Medium |
| Liver | 8.7 | Medium |
| Small intestine | 6.4 | Low |
| Placenta | 4.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 15.2 | Moderate expression |
| HepG2 | 10.8 | Moderate expression |
| SH-SY5Y | 7.5 | Low expression |
| Caco-2 | 9.1 | Moderate expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1264A>G (p.Thr422Ala) | Missense | Rare | Impaired thiamine transport; associated with BBGD |
| c.68G>A (p.Trp23Ter) | Nonsense | Rare | Premature truncation; loss of function |
| c.958G>A (p.Gly320Ser) | Missense | Rare | Reduced transporter activity; THMD2 |
| c.1129C>T (p.Arg377Ter) | Nonsense | Rare | Loss of function; severe phenotype |
Mutation functional classification
Loss of Function (LOF)
Most SLC19A3 mutations are loss-of-function, reducing or abolishing thiamine transport, leading to thiamine deficiency in target tissues.
Gain of Function (GOF)
No gain-of-function mutations have been reported for SLC19A3.
Dominant Negative (DN)
No dominant-negative effects have been described; the disorder is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • integral component of plasma membrane (GO:0005887) | • thiamine transmembrane transporter activity (GO:0015232) |
| • thiamine transport (GO:0015888) | • transmembrane transport (GO:0055085) |
| • membrane (GO:0016020) |
Pathways
• Thiamine metabolism (Reactome: R-HSA-196849)
• Vitamin B1 (thiamine) transport (KEGG: hsa00730)
Protein Summary
The SLC19A3 protein (THTR2) is a 497-amino acid transmembrane transporter with 12 predicted membrane-spanning domains. It mediates high-affinity thiamine uptake at the plasma membrane, particularly in the brain, kidney, and liver. THTR2 is essential for maintaining cellular thiamine levels, and its dysfunction leads to metabolic and neurological disorders.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SLC19A3 Knockout HEK293 Cell Line | EDJ-KQ9546 | Human | 80704 | Details Get a Quote |
| SLC19A3 Knockout A-549 Cell Line | EDJ-KQ36334 | Human | 80704 | Details Get a Quote |
| SLC19A3 Knockout HeLa Cell Line | EDJ-KQ57335 | Human | 80704 | Details Get a Quote |
| SLC19A3 Knockout HCT 116 Cell Line | EDJ-KQ74265 | Human | 80704 | Details Get a Quote |
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