Retinol-binding protein isolation

Affinity chromatography of Clostridium collagenase and clostripapain Purification of mouse interferon Purification by affinity chromatography of retinol-binding protein Isolation of a proviral coding strand of avian myeloblastosis virus from leukaemic chicken myeloblast Purification by affinity chromatography of trypsin... 

Lee K.-H., Wells R.G. and Reed R. (1987). Isolation of an olfactory complementary DNA similarity to retinol-binding protein suggests a role in olfaction. Science 253, 1053-1066. 

In our studies, we have administered tritium-labeled vitamin A in one of its two physiological plasma transport vehicles (associated with either retinol-binding protein or chylomicrons) so that tracer data can be extrapolated to the vitamin A compounds of interest (retinol, retinyl esters, and metabolites). To prepare pH]retinol in its plasma transport complex (Green and Green, 1990b), vitamin A-depleted rats are used as donors to maximize hepatic secretion of the labeled vitamin on acciunulated liver apoRBP. pH]Retinol or pH]retinyl acetate in an emulsion with Tween 40 is administered intravenously to donor rats and blood is harvested 100 min later when plasma radioactivity is maximal. Plasma is isolated and stored under a nitrogen atmosphere at 4°C plasma is used for in vivo studies within 23 days. 

Muto, Y., Goodman, D-W.S. Vitamin A transport in rat plasma isolation and characterization of retinol-binding protein. J. biol. Chem. 247, 2533-2541 (1972)... 

Oxidation of retinol produces retinoic acid tretinoin). The reaction is irreversible. Retinoic acid enters the portal blood, is transported bound to albumin, and is not stored to any great extent. The concentration of retinoic acid in plasma is normally 3-4 ng/mL. A biologically active metabolite, 5,6-epoxyretinoic acid, has been isolated from the intestinal mucosa of vitamin A-deficient rats following administration of H-retinoic acid. Several tissues have specific cellular retinoic acid-binding proteins (CRABPs). 

Two independent families have been described in the literature that have abnormally low blood RBP-ROH levels [114-117]. In one family from Japan, several members reportedly have serum RBP-ROH levels that are approximately 50% that of normal [114-116]. These diminished RBP-ROH levels did not respond to oral administration of retinol or to a protein-rich diet [114-116]. RBP isolated from one affected member of this family demonstrated no differences in its molecular weight, isoelectric point, binding to TTR or immunological properties as compared to RBP isolated from unaffected family members [114-116]. At present it is not clear whether the diminished RBP-ROH levels measured in these individuals arises from some defect in the gene for RBP or if the defect exists in another gene that has an important influence on the normal physiology of RBP-ROH (i.e. on RBP synthesis, secretion, turnover or catabolism). 

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