title: Vitamin D2 in vertebrate evolution.
abstract: 1. The affinities of the specific vitamin D plasma transport proteins for 25-hydroxyergocalciferol and 25-hydroxycholecalciferol were studied in sixty three vertebrate species. 2. Fish, reptile, bird and monotreme plasma proteins bound 25-hydroxyergocalciferol considerably less efficiently than 25-hydroxycholecalciferol. 3. Vitamin D transport proteins from twenty-two placental mammals bound 25-hydroxyergocalciferol and 25-hydroxycholecalciferol with equal efficiency. 4. Proteins from nine mammals bound 25-hydroxycholecalciferol 10-30% more efficiently than 25-hydroxyergocalciferol.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004872:Ergocalciferols / Q000378:metabolism*; D014714:Vertebrates / Q000378:metabolism*
chemical_list: D004872:Ergocalciferols