{"id":"16d808d9-2c3a-5bf1-840d-d54e10191a96","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:a-vision-photoisomerization","predicate":"photoisomerizes-to","statement":"Light activation changes rhodopsin-bound 11-cis-retinal into its all-trans geometry, coupled to receptor activation.","claim_class":"mechanistic","status":"source_derived_draft","evidence_grade":"ungraded","direction":"positive","is_public":true,"mechanism_event_id":"121fa00c-72cf-56b4-8aa4-ad8d3f879fa8","mechanism_event_label":"A photon changes the bound retinoid shape and starts the signal.","subject":{"id":"2df0d238-71af-5f0b-8359-cef18235c4af","slug":"11-cis-retinal","display_name":"11-cis-retinal","entity_type_key":"small_molecule"},"object":{"id":"194eccf2-c7a5-52a6-a0c6-1c1f6d0f3a3e","slug":"all-trans-retinal","display_name":"All-trans-retinal","entity_type_key":"small_molecule"},"evidence_count":1,"mechanism_event":{"id":"121fa00c-72cf-56b4-8aa4-ad8d3f879fa8","stable_key":"dff9f743-3766-5f20-a71e-d6d2bd5bfb6f:a-vision-photoisomerization-event","event_type":"biochemical_relationship","label":"A photon changes the bound retinoid shape and starts the signal.","description":"Light activation changes rhodopsin-bound 11-cis-retinal into its all-trans geometry, coupled to receptor activation.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"22f904b7-271d-5a7b-963c-580663bd37ab","slug":"rhodopsin","display_name":"Rhodopsin","entity_type_key":"protein_state"},"role":"starting photopigment","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"4538a8ef-3b0a-5c56-91f7-58d4c97d7e2a","slug":"photoactivated-rhodopsin","display_name":"Photoactivated rhodopsin","entity_type_key":"protein_state"},"role":"product receptor state","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"2df0d238-71af-5f0b-8359-cef18235c4af","slug":"11-cis-retinal","display_name":"11-cis-retinal","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"194eccf2-c7a5-52a6-a0c6-1c1f6d0f3a3e","slug":"all-trans-retinal","display_name":"All-trans-retinal","entity_type_key":"small_molecule"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Solid-state NMR before/after illumination","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Bound chromophore conversion precedes release of free retinal.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Vitamin A 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":"Bos taurus","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"A photon changes the bound retinoid shape and starts the signal.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[grobner-2000] Observations of light-induced structural changes of retinal within rhodopsin (2000). https://www.nature.com/articles/35015604 DOI: 10.1038/35015604","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Purified rhodopsin","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"a85e9b52-b84e-5f36-bf6a-bee94bacfe44","evidence_kind":"source_excerpt","locator":"Lines 655-664","start_line":655,"end_line":664,"excerpt":"### a-vision-photoisomerization\nLight activation changes rhodopsin-bound 11-cis-retinal into its all-trans geometry, coupled to receptor activation.\nCondition category: normal\nnutrient_topic: Vitamin A research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A photon changes the bound retinoid shape and starts the signal.\norganism: Bos taurus\ntissue_or_cell_type: Purified rhodopsin\nexperimental_model: Solid-state NMR before/after illumination\nlimitations: Bound chromophore conversion precedes release of free retinal.\n[grobner-2000] Observations of light-induced structural changes of retinal within rhodopsin (2000). https://www.nature.com/articles/35015604 DOI: 10.1038/35015604","model_system":"Solid-state NMR before/after illumination","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [grobner-2000] Observations of light-induced structural changes of retinal within rhodopsin (2000). https://www.nature.com/articles/35015604 DOI: 10.1038/35015604","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"0c5474e2-be48-547b-b287-9c07a59c9ff1","stable_key":"import-dff9f743-3766-5f20-a71e-d6d2bd5bfb6f","title":"Vitamin A: forms, mechanisms, deficiency and excess (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":"b217224b262abbd77d6a0c8c9beefff9c022fae4d31e2a5273915d769b9a6546","revision_id":"61008909-871f-575c-b5e2-21542689ea3c","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[],"corrections":[],"research":null}