title: The polyenic system of retinyl phosphate is required for its mannosyl donor activity but not for acceptor activity.
abstract: We investigated whether the polyenic and allylic phosphate systems of retinyl phosphate are essential for its mannosyl acceptor and donor activities in rat liver postnuclear membranes. Perhydromonoeneretinyl phosphate, a compound without growth-promoting activity in vitamin A-deficient animals, was prepared by catalytic hydrogenation of retinol and phosphorylation. Perhydromonoeneretinyl phosphate mannose synthesis from GDP-mannose showed continued accumulation for at least 60 min, while retinyl phosphate mannose synthesis showed a maximum at 20-30 min and then declined. Moreover, only retinyl phosphate stimulated transfer of mannose from GDP-mannose to endogenous proteins, which were separated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Thus, hydrogenation of side-chain double bonds in retinyl phosphate impaired only slightly its mannosyl acceptor activity, but caused loss of mannosyl donor activity.
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004224:Diterpenes; D004591:Electrophoresis, Polyacrylamide Gel; D006155:Guanosine Diphosphate Mannose / Q000378:metabolism*; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D009702:Nucleoside Diphosphate Sugars / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D051381:Rats; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D004224:Diterpenes; D009702:Nucleoside Diphosphate Sugars; D011506:Proteins; D014801:Vitamin A; D006155:Guanosine Diphosphate Mannose; C012532:retinol phosphate; C037614:perhydromonoeneretinyl phosphate