SLC6A14 encodes the amino acid transporter ATB0,+ (also known as B0AT2), a sodium/chloride-dependent neutral amino acid transporter primarily expressed in epithelial tissues including intestine, lung, mammary gland, and brain. SLC6A14 plays a critical role in nutrient uptake, cancer cell metabolism, and has been implicated in obesity, breast cancer, and other metabolic disorders[1][2].
The SLC6A14 locus is on chromosome 9q32 and encodes a 12-transmembrane-domain protein of approximately 629 amino acids. Unlike many SLC6 family members that transport specific neurotransmitters, SLC6A14 has broad substrate specificity for neutral amino acids including leucine, phenylalanine, tryptophan, and glutamine. This broad specificity makes it a major gateway for amino acid uptake in rapidly dividing cells, including cancer cells that have elevated metabolic demands.
SLC6A14 encodes a member of the SLC6 family with the characteristic 12-transmembrane-domain topology:
SLC6A14 operates as a sodium/chloride-coupled neutral amino acid symporter with broad substrate specificity:
| Amino Acid | Transport Efficiency |
|---|---|
| Leucine | High |
| Phenylalanine | High |
| Tryptophan | High |
| Glutamine | Moderate |
| Methionine | Moderate |
| Histidine | Moderate |
In the intestine, SLC6A14 mediates uptake of neutral amino acids from dietary protein:
In the brain, SLC6A14 expression is more limited:
SLC6A14 is overexpressed in multiple cancer types and contributes to tumor growth:
Breast cancer: High SLC6A14 expression correlates with:
Mechanisms include:
Colorectal cancer: SLC6A14 promotes:
Lung cancer: SLC6A14 supports:
SLC6A14 is implicated in obesity through multiple mechanisms[4]:
Studies in mice show that SLC6A14 deletion reduces body weight and fat mass, suggesting therapeutic potential for metabolic disorders.
While less studied in neurodegeneration:
SLC6A14 variants have been associated with:
SLC6A14 inhibition is being explored for:
| Application | Strategy | Status |
|---|---|---|
| Breast cancer | Small molecule inhibitors | Preclinical |
| Obesity | Antisense oligonucleotides | Research |
| Chemotherapy sensitization | siRNA/shRNA | Research |
SLC6A14 shares structural features with other SLC6 transporters:
Cryo-EM structures are being developed and will inform inhibitor design.
Efforts to develop SLC6A14 inhibitors include:
SLC6A14 expression serves as:
SLC6A14 is an attractive target because:
Challenges include:
SLC6A14 inhibition could:
SLC6A14 encodes ATB0,+, a broad-specificity sodium/chloride-coupled neutral amino acid transporter with important roles in nutrient absorption, cancer metabolism, and metabolic disease. The gene is overexpressed in multiple cancer types, making it a potential therapeutic target, while genetic variants influence obesity susceptibility.
Key aspects for neurodegeneration research include:
Metabolic support: SLC6A14 may supply amino acids for neuronal protein synthesis under stress conditions.
Cancer relevance: The strong association with cancer metabolism provides insights into metabolic vulnerabilities that may inform combination therapies.
Therapeutic target: Inhibitors are being developed for cancer and metabolic disorders.
Physiology: The broad substrate specificity distinguishes SLC6A14 from more selective neurotransmitter transporters.
: Broer S, et al. SLC6A14 (ATB0,+): an amino acid transporter with emerging roles in cancer and metabolism. 2019. ↩︎
: Nakanishi T, et al. The role of SLC6A14 in cancer cell metabolism and proliferation. 2023. ↩︎
: Sreekumar S, et al. Amino acid transporter SLC6A14 in breast cancer: mechanisms and biomarkers. 2021. ↩︎
: Karunakaran S, et al. SLC6A14 as a potential therapeutic target in obesity and metabolic disorders. 2020. ↩︎