Chemical synthesis of phosphorylated retinoids. Their mannosyl acceptor activity in rat liver membranes

Phosphorylated retinoids were synthesized by a modification of the procedure that Popják et al. (Popják, G., Cornforth, J. W., Cornforth, R. H., Ryhage, R., and Goodman, D. S. (1962) J. Biol. Chem. 237, 56-61) used to synthesize farnesylpyrophosphate. The all-trans-beta-retinyl phosphate; all-trans-9-(4-methoxy-2,3,6-trimethylphenyl)-3,7-dimethyl-2,4,6,8-nonatetraene-1-yl phosphate; perhydromonoeneretinyl phosphate; all-trans-beta-retinoyl phosphate; 13-cis-beta-retinoyl phosphate derivatives were tested as acceptors of [14C]mannose from GDP-[14C]mannose in a reaction catalyzed by rat liver membranes. The phosphate esters all functioned as acceptors of mannose to give a product chromatographically indistinguishable from endogenous mannosylretinyl phosphate. The mixed anhydrides, however, did not function as mannosyl acceptors. Neither class of compounds had any effect on the biosynthesis of dolichylmannosyl phosphate. Rat liver membranes did not catalyze the transfer of [14C]galactose from UDP-[14C]galactose to retinyl phosphate even at a concentration of retinyl phosphate (0.73 mM) which stimulated formation o mannosylretinyl phosphate by more than 50-fold...