Component
Human thioredoxin-related protein 14 / TXNDC17
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
TRP14 removed cysteinyl mixed-disulfide modifications from human peroxiredoxin 2 and restored its peroxide-reducing activity in vitro.
Experimental context and source evidence
- evidence_access
- Primary full text
- experimental_model
- Recombinant human Prx2; cysteinylation and hydrogen-peroxide reduction assays.
- limitations
- TRP14 repairs this modification; it is not being assigned the ordinary catalytic peroxide-reduction cycle of thioredoxin.
- nutrient_topic
- L-Cysteine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Cysteine
- plain_language
- A cysteine modification can temporarily obstruct another antioxidant enzyme.
- primary_references
- TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
L-Cysteine: sulfur allocation, redox supply and cross-nutrient mechanisms (2026-09-19) · lines 84–90
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Recombinant human Prx2; cysteinylation and hydrogen-peroxide reduction assays. · source_derived_draft · unverified_draft
## l-cysteine-protein-decysteinylation A cysteine modification can temporarily obstruct another antioxidant enzyme. TRP14 removed cysteinyl mixed-disulfide modifications from human peroxiredoxin 2 and restored its peroxide-reducing activity in vitro. Model: Recombinant human Prx2; cysteinylation and hydrogen-peroxide reduction assays. Limitations: TRP14 repairs this modification; it is not being assigned the ordinary catalytic peroxide-reduction cycle of thioredoxin. Evidence access: Primary full text TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
Complete structured claim and evidenceTXNDC17 knockout in human HEK293 cells markedly reduced intracellular cystine reduction; wild-type TRP14 re-expression restored activity whereas its active-site mutant did not.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- evidence_access
- Primary full text
- experimental_model
- Human HEK293 knockout/rescue; fluorescent cystine-reduction assays.
- limitations
- The paper identifies a major rate-limiting route in tested systems, not the only possible reductase in every tissue.
- nutrient_topic
- L-Cysteine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Cysteine
- plain_language
- Importing oxidized cysteine is not enough: the cell must reduce it to use it.
- primary_references
- TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
L-Cysteine: sulfur allocation, redox supply and cross-nutrient mechanisms (2026-09-19) · lines 60–66
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human HEK293 knockout/rescue; fluorescent cystine-reduction assays. · source_derived_draft · unverified_draft
## l-cysteine-trp14-cystine-reduction Importing oxidized cysteine is not enough: the cell must reduce it to use it. TXNDC17 knockout in human HEK293 cells markedly reduced intracellular cystine reduction; wild-type TRP14 re-expression restored activity whereas its active-site mutant did not. Model: Human HEK293 knockout/rescue; fluorescent cystine-reduction assays. Limitations: The paper identifies a major rate-limiting route in tested systems, not the only possible reductase in every tissue. Evidence access: Primary full text TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
Complete structured claim and evidence
What acts on it
The reconstituted TRP14 system used thioredoxin reductase 1 and NADPH to drive disulfide-reduction reactions.
Experimental context and source evidence
- evidence_access
- Primary full text
- experimental_model
- Purified enzyme systems, including human peroxiredoxin-2 decysteinylation.
- limitations
- This establishes a biochemical dependency; selenium or niacin depletion/repletion was not tested in this study.
- nutrient_topic
- L-Cysteine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Cysteine
- plain_language
- The sulfur-supply step depends on an electron supply and another enzyme.
- primary_references
- TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
L-Cysteine: sulfur allocation, redox supply and cross-nutrient mechanisms (2026-09-19) · lines 68–74
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Purified enzyme systems, including human peroxiredoxin-2 decysteinylation. · source_derived_draft · unverified_draft
## l-cysteine-trp14-electron-supply The sulfur-supply step depends on an electron supply and another enzyme. The reconstituted TRP14 system used thioredoxin reductase 1 and NADPH to drive disulfide-reduction reactions. Model: Purified enzyme systems, including human peroxiredoxin-2 decysteinylation. Limitations: This establishes a biochemical dependency; selenium or niacin depletion/repletion was not tested in this study. Evidence access: Primary full text TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
Complete structured claim and evidence
Where it participates (unsigned role)
TXNDC17 knockout shifted human-cell cysteine supply toward transsulfuration, as assessed using labeled methionine and downstream sulfur metabolites.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- evidence_access
- Primary full text
- experimental_model
- Human HEK293 metabolic tracing and enzyme perturbation.
- limitations
- Compensation requires intact transsulfuration and does not prove that B6 supplementation rescues every transport defect.
- nutrient_topic
- L-Cysteine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Cysteine
- plain_language
- An internal synthesis route compensated when imported cystine was harder to use.
- primary_references
- TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
L-Cysteine: sulfur allocation, redox supply and cross-nutrient mechanisms (2026-09-19) · lines 76–82
AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human HEK293 metabolic tracing and enzyme perturbation. · source_derived_draft · unverified_draft
## l-cysteine-trp14-compensation An internal synthesis route compensated when imported cystine was harder to use. TXNDC17 knockout shifted human-cell cysteine supply toward transsulfuration, as assessed using labeled methionine and downstream sulfur metabolites. Model: Human HEK293 metabolic tracing and enzyme perturbation. Limitations: Compensation requires intact transsulfuration and does not prove that B6 supplementation rescues every transport defect. Evidence access: Primary full text TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation. · 2024 · https://pubmed.ncbi.nlm.nih.gov/38811853/ · DOI 10.1038/s44318-024-00117-1
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.