Component
Human ABCD4 Y319C
Patient-associated Tyr319Cys protein variant.
1 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
Purified human ABCD4 Y319C lost detectable cobalamin transport in liposomes, together with loss of ATPase activity.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- evidence_location
- Results: Figures 3, 4, 5; Experimental procedures: liposomes and transport assays
- experimental_model
- Purified human ABCD4/LMBD1 in synthetic liposomes after yeast expression
- exposure
- Variant versus wild-type ABCD4 proteoliposomes
- limitations
- Disease-related variant tested outside cells; ATP hydrolysis and transport are distinct measured endpoints.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Homo sapiens
- plain_language
- The variant disrupted B12 movement across the membrane.
- primary_references
- [kitai-2021-abcd4-transport] The lysosomal protein ABCD4 can transport vitamin B12 across liposomal membranes in vitro (2021). https://pubmed.ncbi.nlm.nih.gov/33845046/ DOI: 10.1016/j.jbc.2021.100654
- tissue_or_cell_type
- Cell-free membrane system
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 655–667
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human ABCD4/LMBD1 in synthetic liposomes after yeast expression · source_derived_draft · unverified_draft
### b12-abcd4-y319c-transport Purified human ABCD4 Y319C lost detectable cobalamin transport in liposomes, together with loss of ATPase activity. Condition category: machinery_impairment nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The variant disrupted B12 movement across the membrane. organism: Homo sapiens tissue_or_cell_type: Cell-free membrane system experimental_model: Purified human ABCD4/LMBD1 in synthetic liposomes after yeast expression limitations: Disease-related variant tested outside cells; ATP hydrolysis and transport are distinct measured endpoints. exposure: Variant versus wild-type ABCD4 proteoliposomes cross_nutrient: false evidence_location: Results: Figures 3, 4, 5; Experimental procedures: liposomes and transport assays [kitai-2021-abcd4-transport] The lysosomal protein ABCD4 can transport vitamin B12 across liposomal membranes in vitro (2021). https://pubmed.ncbi.nlm.nih.gov/33845046/ DOI: 10.1016/j.jbc.2021.100654
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.