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Do not generalize the early clone to every subsequently described splice variant.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Phosphorus research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"phosphorus","display_name":"Phosphorus","entity_type_key":"nutrient_element"}},{"dimension":"organism","value_text":"Human PCYT1B expressed in African-green-monkey-derived COS-7 cells","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The pathway feeds a phosphorus-containing membrane lipid; it is distinct from free phosphate transport.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[phosphorus-p9593753] Cloning and characterization of a second human CTP:phosphocholine cytidylyltransferase. (1998). https://pubmed.ncbi.nlm.nih.gov/9593753/ DOI: 10.1074/jbc.273.22.14022","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Cytoplasm and phospholipid biosynthesis","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"f85a36a8-fa41-5ec5-8e5e-061c6331780b","evidence_kind":"source_excerpt","locator":"Lines 711-722","start_line":711,"end_line":722,"excerpt":"### phosphorus-pcyt-lipid\nHuman CCTbeta expression enhanced radiolabeling of phosphatidylcholine in COS-7 cells.\nCondition category: normal\nnutrient_topic: Phosphorus research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The pathway feeds a phosphorus-containing membrane lipid; it is distinct from free phosphate transport.\norganism: Human PCYT1B expressed in African-green-monkey-derived COS-7 cells\ntissue_or_cell_type: Cytoplasm and phospholipid biosynthesis\nexperimental_model: Human isoform cloning and COS-7 expression studies\nlimitations: Expression-system findings; maximum activity required lipid regulators. Do not generalize the early clone to every subsequently described splice variant.\nexposure: CCTbeta transfection and catalytic assays with lipid regulators\nevidence_span: {\"source_cache\": \"artifacts/phosphorus-research/9593753.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"6ed2c0c0ceaa7eb2efb90c66565bae51b71023f77cdd0224159fd9814e3b7d45\", \"start_char\": 0, \"end_char\": 1766, \"text_sha256\": \"6ed2c0c0ceaa7eb2efb90c66565bae51b71023f77cdd0224159fd9814e3b7d45\"}\n[phosphorus-p9593753] Cloning and characterization of a second human CTP:phosphocholine cytidylyltransferase. (1998). https://pubmed.ncbi.nlm.nih.gov/9593753/ DOI: 10.1074/jbc.273.22.14022","model_system":"Human isoform cloning and COS-7 expression studies","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [phosphorus-p9593753] Cloning and characterization of a second human CTP:phosphocholine cytidylyltransferase. (1998). https://pubmed.ncbi.nlm.nih.gov/9593753/ DOI: 10.1074/jbc.273.22.14022","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"cfdefe70-3a09-5e2e-97c8-46626382e4b4","stable_key":"import-fe6af7fc-7372-5c4f-9c2f-2bbf56695397","title":"Phosphorus: metabolism, signaling and nutrient connections (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":"a04956d7177582b749608db404e6b691ae3b28a9f2f762781b6d820b461044fb","revision_id":"713b78f5-1133-5b2b-8822-20c0852e3715","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}