Component
Human neutral amino acid exchanger ASCT1 / SLC1A4
Context-specific entity; species, compartment and exposure are stated on each claim.
4 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
SLC1A4 perturbation and isotope-flux studies supported a role for SLC1A4, alongside other transporters, in rapid alanine exchange by human pancreatic stellate cells.
Experimental context and source evidence
- evidence_access
- Primary full text
- experimental_model
- Human PSC transporter and flux experiments.
- limitations
- SLC1A4 was not the sole alanine exporter and exchange is not equivalent to an irreversible one-way pump.
- nutrient_topic
- L-Alanine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Alanine
- plain_language
- An exchanger helps neighboring cells share alanine.
- primary_references
- Selective Alanine Transporter Utilization Creates a Targetable Metabolic Niche in Pancreatic Cancer. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32341021/ · DOI 10.1158/2159-8290.CD-19-0959
L-Alanine: carbon, nitrogen, protein synthesis and cross-nutrient mechanisms (2026-09-19) · lines 176–182
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human PSC transporter and flux experiments. · source_derived_draft · unverified_draft
## alanine-psc-exchanger An exchanger helps neighboring cells share alanine. SLC1A4 perturbation and isotope-flux studies supported a role for SLC1A4, alongside other transporters, in rapid alanine exchange by human pancreatic stellate cells. Model: Human PSC transporter and flux experiments. Limitations: SLC1A4 was not the sole alanine exporter and exchange is not equivalent to an irreversible one-way pump. Evidence access: Primary full text Selective Alanine Transporter Utilization Creates a Targetable Metabolic Niche in Pancreatic Cancer. · 2020 · https://pubmed.ncbi.nlm.nih.gov/32341021/ · DOI 10.1158/2159-8290.CD-19-0959
Complete structured claim and evidenceTwo unrelated individuals with biallelic SLC1A4 variants had severe developmental delay, progressive microcephaly, seizures, spasticity and thin corpus callosum.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- evidence_access
- Primary abstract
- experimental_model
- Human trio-exome analysis and structural prediction.
- limitations
- The proposed astrocyte-to-neuron transport mechanism was not directly measured in these two patients.
- nutrient_topic
- L-Serine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Serine
- plain_language
- A transport defect can matter even when amino-acid synthesis is present.
- primary_references
- SLC1A4 mutations cause a novel disorder of intellectual disability, progressive microcephaly, spasticity and thin corpus callosum. · 2015 · https://pubmed.ncbi.nlm.nih.gov/26138499/ · DOI 10.1111/cge.12637
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
L-Serine: synthesis, one-carbon metabolism, lipids and cross-nutrient mechanisms (2026-09-19) · lines 334–340
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human trio-exome analysis and structural prediction. · source_derived_draft · unverified_draft
## l-serine-asct1-genetic A transport defect can matter even when amino-acid synthesis is present. Two unrelated individuals with biallelic SLC1A4 variants had severe developmental delay, progressive microcephaly, seizures, spasticity and thin corpus callosum. Model: Human trio-exome analysis and structural prediction. Limitations: The proposed astrocyte-to-neuron transport mechanism was not directly measured in these two patients. Evidence access: Primary abstract SLC1A4 mutations cause a novel disorder of intellectual disability, progressive microcephaly, spasticity and thin corpus callosum. · 2015 · https://pubmed.ncbi.nlm.nih.gov/26138499/ · DOI 10.1111/cge.12637
Complete structured claim and evidenceCloned human ASCT1 transported alanine, serine, cysteine and threonine rather than glutamate or aspartate.
Experimental context and source evidence
- evidence_access
- Primary abstract
- experimental_model
- Human cDNA cloning and transporter characterization.
- limitations
- Substrate overlap alone does not quantify competition during ordinary dietary intake.
- nutrient_topic
- L-Threonine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Threonine
- plain_language
- Several amino acids share a cellular entry and exchange route.
- primary_references
- Human neutral amino acid transporter ASCT1: structure of the gene (SLC1A4) and localization to chromosome 2p13-p15. · 1994 · https://pubmed.ncbi.nlm.nih.gov/7896285/ · DOI 10.1006/geno.1994.1577
- transport_effect
- depends A substrate-selectivity record. ASCT1 is an obligatory exchanger and no direction is stated.
- transport_pool
- the cytosol across the plasma membrane A substrate-selectivity record. ASCT1 is an obligatory exchanger and no direction is stated.
L-Threonine: translation, intestinal barrier, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 18–24
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human cDNA cloning and transporter characterization. · source_derived_draft · unverified_draft
## l-threonine-asct1-substrate Several amino acids share a cellular entry and exchange route. Cloned human ASCT1 transported alanine, serine, cysteine and threonine rather than glutamate or aspartate. Model: Human cDNA cloning and transporter characterization. Limitations: Substrate overlap alone does not quantify competition during ordinary dietary intake. Evidence access: Primary abstract Human neutral amino acid transporter ASCT1: structure of the gene (SLC1A4) and localization to chromosome 2p13-p15. · 1994 · https://pubmed.ncbi.nlm.nih.gov/7896285/ · DOI 10.1006/geno.1994.1577
Complete structured claim and evidence
What acts on it
L-threonine inhibited radiolabeled L-serine uptake in HEK cells expressing human ASCT1, with an IC50 of 181 ± 75 micromolar.
Experimental context and source evidence
- evidence_access
- Primary full-text Table 5, publisher PDF
- experimental_model
- Table 5: three observations per transporter; heterologous human-transporter HEK cell assays.
- limitations
- An inhibition concentration in culture is not a dietary threshold or proof of reduced brain serine.
- nutrient_topic
- L-Threonine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Threonine
- plain_language
- Threonine can compete with serine in a defined transporter assay.
- primary_references
- D-Serine Is a Substrate for Neutral Amino Acid Transporters ASCT1/SLC1A4 and ASCT2/SLC1A5, and Is Transported by Both Subtypes in Rat Hippocampal Astrocyte Cultures. · 2016 · https://pubmed.ncbi.nlm.nih.gov/27272177/ · DOI 10.1371/journal.pone.0156551
L-Threonine: translation, intestinal barrier, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 26–32
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Table 5: three observations per transporter; heterologous human-transporter HEK cell assays. · source_derived_draft · unverified_draft
## l-threonine-serine-competition-slc1a4 Threonine can compete with serine in a defined transporter assay. L-threonine inhibited radiolabeled L-serine uptake in HEK cells expressing human ASCT1, with an IC50 of 181 ± 75 micromolar. Model: Table 5: three observations per transporter; heterologous human-transporter HEK cell assays. Limitations: An inhibition concentration in culture is not a dietary threshold or proof of reduced brain serine. Evidence access: Primary full-text Table 5, publisher PDF D-Serine Is a Substrate for Neutral Amino Acid Transporters ASCT1/SLC1A4 and ASCT2/SLC1A5, and Is Transported by Both Subtypes in Rat Hippocampal Astrocyte Cultures. · 2016 · https://pubmed.ncbi.nlm.nih.gov/27272177/ · DOI 10.1371/journal.pone.0156551
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.