Component
Transthyretin loss
Ttr-knockout state in the cited mice.
2 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.
Where it participates (unsigned role)
Ttr-null mice had plasma retinol averaging about 6% of wild type.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- evidence_location
- Abstract
- experimental_model
- Ttr-knockout mice; circulating and tissue retinoid assays.
- exposure
- Ttr knockout; pooled plasma comparison.
- limitations
- Not evidence that every tissue was depleted; the mechanism of the plasma fall was incompletely resolved.
- nutrient_topic
- Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
- organism
- Mus musculus
- outcome
- Ttr-null mice had plasma retinol averaging about 6% of wild type.
- plain_language
- Loss of the RBP-associated carrier strongly lowers the blood measurement.
- primary_references
- [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
- tissue_or_cell_type
- Plasma
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 402–414
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Ttr-knockout mice; circulating and tissue retinoid assays. · source_derived_draft · unverified_draft
### va-ttr-plasma-retinol Ttr-null mice had plasma retinol averaging about 6% of wild type. Condition category: machinery_impairment nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Loss of the RBP-associated carrier strongly lowers the blood measurement. organism: Mus musculus tissue_or_cell_type: Plasma experimental_model: Ttr-knockout mice; circulating and tissue retinoid assays. limitations: Not evidence that every tissue was depleted; the mechanism of the plasma fall was incompletely resolved. exposure: Ttr knockout; pooled plasma comparison. outcome: Ttr-null mice had plasma retinol averaging about 6% of wild type. evidence_location: Abstract [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
Complete structured claim and evidenceTtr-null mice maintained normal retinol/retinyl-ester levels in the tested liver and extrahepatic tissues despite low plasma retinol.
Experimental context and source evidence
- availability_state
- biomarker_context Imported condition classification; unverified.
- evidence_location
- Abstract
- experimental_model
- Ttr-knockout mice; circulating and tissue retinoid assays.
- exposure
- Ttr knockout tissue assays.
- limitations
- Normal tissue pools do not establish every cell function or long-term diet-independent adequacy.
- nutrient_topic
- Vitamin A research collection; topical membership is not evidence of a direct dietary effect. · Vitamin A
- organism
- Mus musculus
- outcome
- Ttr-null mice maintained normal retinol/retinyl-ester levels in the tested liver and extrahepatic tissues despite low plasma retinol.
- plain_language
- Low blood retinol did not mean low stores in these sampled tissues.
- primary_references
- [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
- tissue_or_cell_type
- Liver, testis, kidney, spleen and eye cups
- trigger_kind
- biomarker_context Imported condition classification; unverified.
Vitamin A: forms, mechanisms, deficiency and excess (2026-09-17) · lines 416–428
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Ttr-knockout mice; circulating and tissue retinoid assays. · source_derived_draft · unverified_draft
### va-ttr-tissue-pool-boundary Ttr-null mice maintained normal retinol/retinyl-ester levels in the tested liver and extrahepatic tissues despite low plasma retinol. Condition category: biomarker_context nutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect. plain_language: Low blood retinol did not mean low stores in these sampled tissues. organism: Mus musculus tissue_or_cell_type: Liver, testis, kidney, spleen and eye cups experimental_model: Ttr-knockout mice; circulating and tissue retinoid assays. limitations: Normal tissue pools do not establish every cell function or long-term diet-independent adequacy. exposure: Ttr knockout tissue assays. outcome: Ttr-null mice maintained normal retinol/retinyl-ester levels in the tested liver and extrahepatic tissues despite low plasma retinol. evidence_location: Abstract [va-wei-1995] Studies on the metabolism of retinol and retinol-binding protein in transthyretin-deficient mice produced by homologous recombination (1995). https://pubmed.ncbi.nlm.nih.gov/7822324/ DOI: 10.1074/jbc.270.2.866
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.