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(2018). https://pubmed.ncbi.nlm.nih.gov/29402915/ DOI: 10.1038/s41598-018-20731-4","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"HEK293T biosynthetic trafficking","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"trigger_kind","value_text":"machinery_impairment","comparator":null,"unit":null,"notes":"Imported condition classification; unverified.","entity":null}],"evidence":[{"id":"e8436cd0-4244-57cc-a476-db6d57c38de8","evidence_kind":"source_excerpt","locator":"Lines 335-346","start_line":335,"end_line":346,"excerpt":"### b12-abs-glycosylation-quadruple-mutant\nCombined N711D/N749D/N781D/N857D substitutions in rat mini-cubilin abolished mature glycosylation and surface targeting with human AMN; the tested smaller combinations did not.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Several glycosylation sites jointly support receptor maturation.\norganism: Rattus norvegicus construct; Homo sapiens AMN and host cells\ntissue_or_cell_type: HEK293T biosynthetic trafficking\nexperimental_model: Rat mini-cubilin 4567ND versus wild type in HEK293T cells coexpressing human AMN\nlimitations: Engineered combined construct; does not show that every single site is individually indispensable. B12 absorption itself was not measured.\nexposure: Four Asn-to-Asp substitutions; Figure 6 and Supplementary Figure 11\ncross_nutrient: false\n[udagawa-2018-glycosylation] Amnionless-mediated glycosylation is crucial for cell surface targeting of cubilin in renal and intestinal cells. (2018). https://pubmed.ncbi.nlm.nih.gov/29402915/ DOI: 10.1038/s41598-018-20731-4","model_system":"Rat mini-cubilin 4567ND versus wild type in HEK293T cells coexpressing human AMN","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [udagawa-2018-glycosylation] Amnionless-mediated glycosylation is crucial for cell surface targeting of cubilin in renal and intestinal cells. 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