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(2019). https://pubmed.ncbi.nlm.nih.gov/31694912/ DOI: 10.1074/jbc.ra119.011169","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"HEK293S GnTI-negative homogenates","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":"2176e3d0-eabb-5d16-a6fd-a4357d516a3a","evidence_kind":"source_excerpt","locator":"Lines 453-466","start_line":453,"end_line":466,"excerpt":"### vae-rgr-k255a-photoactivity\nBovine RGR K255A produced little 11-cis-retinal under illumination despite expression comparable to wild-type RGR in HEK293S GnTI-negative cells.\nCondition category: machinery_impairment\nnutrient_topic: Vitamin A expansion research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: Disrupting the retinal-binding lysine impaired the light-driven reaction.\norganism: Bos taurus protein in Homo sapiens cells\ntissue_or_cell_type: HEK293S GnTI-negative homogenates\nexperimental_model: Recombinant bovine wild-type/K255A RGR comparison\nlimitations: Construct-specific assay; K255A numbering is retained from this paper.\nexposure: All-trans-retinal and 530-nm light, with CRALBP; Figure 7.\ncross_nutrient: false\nevidence_location: Results/Figure 7a-c\nnutrient: Vitamin A\n[vav-zhang2019] Photic generation of 11-cis-retinal in bovine retinal pigment epithelium. 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