Cellular retinol-binding protein from rat liver. Purification and characterization.
Cellular retinol-binding protein has been purified to homogeneity from rat liver. The procedures utilized in the purification included acid precipitation, gel filtration on Sephadex G-75 and G-50, and chromatography on DEAE-cellulose. The binding protein was purified approximately 3,500-fold, based on total soluble liver protein. The protein is a single polypeptide chain with a molecular weight of 14,600 based on information obtained by the techniques of sedimentation equilibrium analysis, gel filtration, and sodium dodecyl sulfate-polyacrylamide electrophoresis. The protein binds retinol with high affinity; the appparent dissociation constant was determined by fluorometric titration to be 1.6 X 10(-8) M. Retinol bound to the protein has an absorption spectrum (lambdamax, 350 nm) considerably altered from the spectrum of retinol in ethanol (lambdamax, 325 nm).
D000818:Animals; D008099:Liver / Q000378:metabolism*; D008970:Molecular Weight; D051381:Rats; D012177:Retinol-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D054840:Retinol-Binding Proteins, Cellular; D013050:Spectrometry, Fluorescence; D014801:Vitamin A / Q000378:metabolism
D012177:Retinol-Binding Proteins; D054840:Retinol-Binding Proteins, Cellular; D014801:Vitamin A