{"id":"13e61e0f-2183-5362-abe6-cc30ca9d8072","stable_key":"3c852f36-7951-5fd9-9013-d771a8d16d8a:va-repro-cyp26b1-null-meiosis","predicate":"deletion_advances","statement":"Cyp26b1-null mouse fetal testes contained germ cells entering meiosis precociously.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"e42e67ac-f710-5d97-8818-62d2fb892f5c","mechanism_event_label":"A missing catabolic enzyme disrupts fetal male germ-cell timing.","subject":{"id":"6c4c5a68-401c-5e85-a999-d3f1926d5b12","slug":"mouse-cyp26b1-gene","display_name":"Mouse Cyp26b1 gene","entity_type_key":"gene"},"object":{"id":"155bea0b-22fa-5f4c-b0d5-ee64b94435c5","slug":"mouse-germ-cell-meiotic-initiation","display_name":"Mouse germ-cell meiotic initiation","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"e42e67ac-f710-5d97-8818-62d2fb892f5c","stable_key":"3c852f36-7951-5fd9-9013-d771a8d16d8a:va-repro-cyp26b1-null-meiosis-event","event_type":"biochemical_relationship","label":"A missing catabolic enzyme disrupts fetal male germ-cell timing.","description":"Cyp26b1-null mouse fetal testes contained germ cells entering meiosis precociously.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"0ea00464-7bee-5899-9894-6a0a9ef7a8d1","slug":"cyp26b1","display_name":"Cytochrome P450 26B1 / CYP26B1","entity_type_key":"protein"},"role":"deleted_catabolic_enzyme","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"05487b29-8c59-5af8-83cf-cf9c79c5ecb8","slug":"all-trans-retinoic-acid","display_name":"All-trans-retinoic acid","entity_type_key":"small_molecule"},"role":"regulated_retinoid","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"6c4c5a68-401c-5e85-a999-d3f1926d5b12","slug":"mouse-cyp26b1-gene","display_name":"Mouse Cyp26b1 gene","entity_type_key":"gene"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"155bea0b-22fa-5f4c-b0d5-ee64b94435c5","slug":"mouse-germ-cell-meiotic-initiation","display_name":"Mouse germ-cell meiotic initiation","entity_type_key":"cellular_process"},"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":"experimental_model","value_text":"Embryonic knockout comparison","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"Constitutive Cyp26b1 deletion; exact sampling ages unavailable in retrieved abstract.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"This establishes a knockout phenotype, not a human RA dose threshold.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin A expansion research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"vitamin-a","display_name":"Vitamin A","entity_type_key":"chemical_species"}},{"dimension":"organism","value_text":"Mus musculus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A missing catabolic enzyme disrupts fetal male germ-cell timing.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[bowles2006] Retinoid signaling determines germ cell fate in mice. (2006). https://pubmed.ncbi.nlm.nih.gov/16574820/ DOI: 10.1126/science.1125691","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"fetal testis","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":"9348f069-bd14-5bfa-b194-857e9d50c674","evidence_kind":"source_excerpt","locator":"Lines 200-211","start_line":200,"end_line":211,"excerpt":"### va-repro-cyp26b1-null-meiosis\nCyp26b1-null mouse fetal testes contained germ cells entering meiosis precociously.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin A expansion research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A missing catabolic enzyme disrupts fetal male germ-cell timing.\norganism: Mus musculus\ntissue_or_cell_type: fetal testis\nexperimental_model: Embryonic knockout comparison\nlimitations: This establishes a knockout phenotype, not a human RA dose threshold.\nexposure: Constitutive Cyp26b1 deletion; exact sampling ages unavailable in retrieved abstract.\ncross_nutrient: false\n[bowles2006] Retinoid signaling determines germ cell fate in mice. 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