Component
Human LMBRD1 gene
Human LMBRD1 gene
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.
What it acts on
CRISPR LMBRD1 knockout in HEK293 cells reduced the ABCD4 signal overlapping lysosomal fractions to about 40% of control, while total ABCD4 was similar.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- evidence_location
- Results: Figures 1, 6, 7; Methods: cell lines and CRISPR
- experimental_model
- HEK293 CRISPR knockout and density-gradient immunoblotting
- exposure
- LMBRD1 knockout versus wild type
- limitations
- Fractionation-based localization; residual lysosomal signal remains and is not 40% residual transport activity.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Homo sapiens
- plain_language
- Deleting the escort changed where the transporter was located.
- primary_references
- [kawaguchi-2016-lmbd1-escort] Translocation of the ABC transporter ABCD4 from the endoplasmic reticulum to lysosomes requires the escort protein LMBD1 (2016). https://pubmed.ncbi.nlm.nih.gov/27456980/ DOI: 10.1038/srep30183
- tissue_or_cell_type
- Human embryonic kidney-derived cell line
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 585–597
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · HEK293 CRISPR knockout and density-gradient immunoblotting · source_derived_draft · unverified_draft
### b12-lmbrd1-ko-localization CRISPR LMBRD1 knockout in HEK293 cells reduced the ABCD4 signal overlapping lysosomal fractions to about 40% of control, while total ABCD4 was similar. Condition category: machinery_impairment nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Deleting the escort changed where the transporter was located. organism: Homo sapiens tissue_or_cell_type: Human embryonic kidney-derived cell line experimental_model: HEK293 CRISPR knockout and density-gradient immunoblotting limitations: Fractionation-based localization; residual lysosomal signal remains and is not 40% residual transport activity. exposure: LMBRD1 knockout versus wild type cross_nutrient: false evidence_location: Results: Figures 1, 6, 7; Methods: cell lines and CRISPR [kawaguchi-2016-lmbd1-escort] Translocation of the ABC transporter ABCD4 from the endoplasmic reticulum to lysosomes requires the escort protein LMBD1 (2016). https://pubmed.ncbi.nlm.nih.gov/27456980/ DOI: 10.1038/srep30183
Complete structured claim and evidence
Where it participates (unsigned role)
Transfection with wild-type LMBD1 restored cobalamin coenzyme synthesis and function in cultured fibroblasts from individuals with the cblF defect.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- evidence_location
- Abstract; Figure 4 caption
- experimental_model
- Human cblF patient fibroblast complementation
- exposure
- Wild-type LMBD1 expression construct
- limitations
- Cultured-cell experiment; not dietary deficiency, a serum B12 threshold, or a human treatment effect.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Homo sapiens
- plain_language
- Restoring the missing lysosomal protein let patient cells make usable B12 cofactors.
- primary_references
- [rutsch-2009-lmbrd1] Identification of a putative lysosomal cobalamin exporter altered in the cblF defect of vitamin B12 metabolism (2009). https://pubmed.ncbi.nlm.nih.gov/19136951/ DOI: 10.1038/ng.294
- tissue_or_cell_type
- Skin-derived fibroblasts
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 543–555
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human cblF patient fibroblast complementation · source_derived_draft · unverified_draft
### b12-lmbrd1-rescue Transfection with wild-type LMBD1 restored cobalamin coenzyme synthesis and function in cultured fibroblasts from individuals with the cblF defect. Condition category: machinery_impairment nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: Restoring the missing lysosomal protein let patient cells make usable B12 cofactors. organism: Homo sapiens tissue_or_cell_type: Skin-derived fibroblasts experimental_model: Human cblF patient fibroblast complementation limitations: Cultured-cell experiment; not dietary deficiency, a serum B12 threshold, or a human treatment effect. exposure: Wild-type LMBD1 expression construct cross_nutrient: false evidence_location: Abstract; Figure 4 caption [rutsch-2009-lmbrd1] Identification of a putative lysosomal cobalamin exporter altered in the cblF defect of vitamin B12 metabolism (2009). https://pubmed.ncbi.nlm.nih.gov/19136951/ DOI: 10.1038/ng.294
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.