{"id":"aaf9a631-daa2-51c8-ac4c-a7782bce9466","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abcd4-y482a-binding","predicate":"reduces-binding-to","statement":"Human ABCD4 Y482A showed markedly impaired association with LMBD1 in HEK293T co-immunoprecipitation compared with wild-type ABCD4.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"b6291aa3-6f5a-5d28-acd2-3f429845afd8","mechanism_event_label":"Changing the transporter’s interface weakened its association with the escort.","subject":{"id":"f89dc4b9-2a78-5eab-acd1-ee40633577fc","slug":"abcd4-y482a","display_name":"Human ABCD4 Y482A","entity_type_key":"protein_state"},"object":{"id":"3cf57c43-b33e-5c4e-a53d-dc80695775bb","slug":"lmbrd1","display_name":"Human LMBD1 lysosomal membrane protein","entity_type_key":"protein"},"evidence_count":1,"mechanism_event":{"id":"b6291aa3-6f5a-5d28-acd2-3f429845afd8","stable_key":"7fc92b9e-9cbf-556e-8719-6b5244625250:b12-abcd4-y482a-binding-event","event_type":"biochemical_relationship","label":"Changing the transporter’s interface weakened its association with the escort.","description":"Human ABCD4 Y482A showed markedly impaired association with LMBD1 in HEK293T co-immunoprecipitation compared with wild-type ABCD4.","status":"provisional","compartment":{"slug":"lysosome","display_name":"Lysosome"},"participants":[{"entity":{"id":"831afa98-dacd-516d-ae1e-680432a78525","slug":"abcd4","display_name":"Human ABCD4 lysosomal cobalamin transporter","entity_type_key":"protein"},"role":"wild-type comparator","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"b6d9b937-895d-5e0a-8cc5-0454a0b7d373","slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"},"role":"related cargo","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"f89dc4b9-2a78-5eab-acd1-ee40633577fc","slug":"abcd4-y482a","display_name":"Human ABCD4 Y482A","entity_type_key":"protein_state"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"3cf57c43-b33e-5c4e-a53d-dc80695775bb","slug":"lmbrd1","display_name":"Human LMBD1 lysosomal membrane protein","entity_type_key":"protein"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"availability_state","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null},{"dimension":"cross_nutrient","value_text":"false","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"evidence_location","value_text":"Figure 4c","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"HEK293T human tagged-protein interface mutagenesis","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"ABCD4-HA Y482A plus LMBD1-GFP-Flag versus wild type","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Experimental Y482A substitution and overexpression; no claim that this is a disease allele or a direct flux measurement.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-b12","display_name":"Vitamin B12 (cobalamins)","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"Changing the transporter’s interface weakened its association with the escort.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[liu-2026-abcd4-interface] Structural basis for LMBD1-dependent trafficking and cobalamin export of ABCD4 (2026). https://pubmed.ncbi.nlm.nih.gov/42303638/ DOI: 10.1038/s41467-026-74552-5","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Human embryonic kidney-derived cell line","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; 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Study references: [liu-2026-abcd4-interface] Structural basis for LMBD1-dependent trafficking and cobalamin export of ABCD4 (2026). https://pubmed.ncbi.nlm.nih.gov/42303638/ DOI: 10.1038/s41467-026-74552-5","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"73145023-2982-5848-aff2-8d8875d6b9c5","stable_key":"import-7fc92b9e-9cbf-556e-8719-6b5244625250","title":"Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"ad5b3a51d36e856aa7fdfd1cc23f690b094689bad87d28e1a621a54675a01c92","revision_id":"118bd616-0c13-549f-bfeb-bc439715b89c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}