Component
mu-Crystallin / CRYM
Independent protein record; interpretation is limited by each linked claim and its study context.
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)
Human MCT8 structure places the T3 carboxylate against Arg371 and its iodine atoms in hydrophobic pockets; substitutions of substrate-contact residues reduce cellular T3 uptake.
Experimental context and source evidence
- evidence_locator
- Results: T3 recognition, Figure 3; Methods
- evidence_spans
- [{"source_document": "artifacts/iodine-metabolism-sources/40140416.txt", "locator": "Results: T3 recognition, Figure 3; Methods", "start_char": 679, "end_char": 2779}]
- experimental_model
- Purified tagged human MCT8 from HEK293F cells; cryo-EM and cell-based mutagenesis
- exposure
- Cryo-EM preparation: 1.5 mM T3. HeLa uptake assay: human MCT8 and CRYM coexpression; 1 nM unlabeled T3 plus 0.02 microcuries 125I-T3 for 30 minutes at 37 C.
- limitations
- Purified structural occupancy is not a physiological concentration threshold. Individual mutations and their effects are not identical.
- nutrient_topic
- Iodine research collection; topical membership is not evidence of a direct dietary effect. · Iodine
- organism
- Human
- plain_language
- The transporter recognizes the shape and chemical groups of iodine-containing T3.
- primary_references
- [i-met-40140416] Structural insights into thyroid hormone transporter MCT8. (2025). https://pubmed.ncbi.nlm.nih.gov/40140416/ DOI: 10.1038/s41467-025-58131-8
- tissue_or_cell_type
- HeLa cells for transport; HEK293F cells for protein production
Iodine: thyroid hormone production, deficiency, excess and nutrient interactions (2026-09-17) · lines 912–924
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified tagged human MCT8 from HEK293F cells; cryo-EM and cell-based mutagenesis · source_derived_draft · unverified_draft
### i-met-mct8-t3-recognition Human MCT8 structure places the T3 carboxylate against Arg371 and its iodine atoms in hydrophobic pockets; substitutions of substrate-contact residues reduce cellular T3 uptake. Condition category: normal nutrient_topic: Iodine research collection; topical membership is not evidence of a direct dietary effect. plain_language: The transporter recognizes the shape and chemical groups of iodine-containing T3. organism: Human tissue_or_cell_type: HeLa cells for transport; HEK293F cells for protein production experimental_model: Purified tagged human MCT8 from HEK293F cells; cryo-EM and cell-based mutagenesis limitations: Purified structural occupancy is not a physiological concentration threshold. Individual mutations and their effects are not identical. exposure: Cryo-EM preparation: 1.5 mM T3. HeLa uptake assay: human MCT8 and CRYM coexpression; 1 nM unlabeled T3 plus 0.02 microcuries 125I-T3 for 30 minutes at 37 C. evidence_locator: Results: T3 recognition, Figure 3; Methods evidence_spans: [{"source_document": "artifacts/iodine-metabolism-sources/40140416.txt", "locator": "Results: T3 recognition, Figure 3; Methods", "start_char": 679, "end_char": 2779}] [i-met-40140416] Structural insights into thyroid hormone transporter MCT8. (2025). https://pubmed.ncbi.nlm.nih.gov/40140416/ DOI: 10.1038/s41467-025-58131-8
Complete structured claim and evidenceCRYM ketimine reductase reduces P2C to L-pipecolate using reduced nicotinamide cofactors.
Experimental context and source evidence
- experimental_model
- Recombinant human CRYM and mammalian enzyme substrate assays
- limitations
- Catalytic capacity does not determine the route's quantitative contribution to human brain lysine clearance.
- organism
- Homo sapiens enzyme; ovine enzyme used for initial purification
- plain_language
- A ring-shaped intermediate can be reduced to pipecolate.
- primary_references
- [hallen2011] Mammalian forebrain ketimine reductase identified as mu-crystallin; potential regulation by thyroid hormones. (2011). https://pubmed.ncbi.nlm.nih.gov/21332720/ DOI: 10.1111/j.1471-4159.2011.07220.x [hallen2015] Insights into Enzyme Catalysis and Thyroid Hormone Regulation of Cerebral Ketimine Reductase/mu-Crystallin Under Physiological Conditions. (2015). https://pubmed.ncbi.nlm.nih.gov/25931162/ DOI: 10.1007/s11064-015-1590-5
- tissue_or_cell_type
- Cytosolic enzyme; forebrain biochemical context
L-Lysine: mechanism-first literature curation (2026-09-17) · lines 336–345
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human CRYM and mammalian enzyme substrate assays · source_derived_draft · unverified_draft
### crym-p2c-reduction CRYM ketimine reductase reduces P2C to L-pipecolate using reduced nicotinamide cofactors. Plain language: A ring-shaped intermediate can be reduced to pipecolate. Condition category: normal organism: Homo sapiens enzyme; ovine enzyme used for initial purification tissue_or_cell_type: Cytosolic enzyme; forebrain biochemical context experimental_model: Recombinant human CRYM and mammalian enzyme substrate assays limitations: Catalytic capacity does not determine the route's quantitative contribution to human brain lysine clearance. [hallen2011] Mammalian forebrain ketimine reductase identified as mu-crystallin; potential regulation by thyroid hormones. (2011). https://pubmed.ncbi.nlm.nih.gov/21332720/ DOI: 10.1111/j.1471-4159.2011.07220.x [hallen2015] Insights into Enzyme Catalysis and Thyroid Hormone Regulation of Cerebral Ketimine Reductase/mu-Crystallin Under Physiological Conditions. (2015). https://pubmed.ncbi.nlm.nih.gov/25931162/ DOI: 10.1007/s11064-015-1590-5
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.