Effects of retinol and retinol palmitate on glycolipid and glycoprotein galactosyltransferase activities of rat liver plasma membranes.
Effects of retinol and retinol palmitate on glycolipid and glycoprotein galactosyltransferase activities of rat liver plasma membranes.
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视黄醇和视黄醇棕榈酸酯对大鼠肝质膜糖脂和糖蛋白半乳糖基转移酶活性的影响。
DOI：
10.1016/s0006-291x(80)80104-5
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发表时间：
1980
影响因子：
3.1
通讯作者：
Morré,DJ
中科院分区：
文献类型：
--
作者：
Creek,KE;Morré,DJ
从大鼠肝脏分离的纯化质膜对内源性糖脂和糖蛋白受体表现出低水平的半乳糖转移酶活性。视黄醇（0.005 mM）的加入促进了[14C]半乳糖从UDP-[14C]半乳糖向质膜内源性糖脂和糖蛋白受体的转移，而视黄醇浓度的高低或抑制或没有影响。视黄醇棕榈酸酯（0.005 mM）刺激[14C]半乳糖从UDP-[14C]半乳糖转移到糖脂中，但对分离的质膜的糖蛋白受体不起作用，并且在浓度高于0.05 mM时具有抑制作用。在缺乏或存在视黄醇（0.025或0.005 mM）的孵育中添加ATP （0.5 mM）可抑制[14C]半乳糖向糖脂和糖蛋白受体的结合。在含有UDP-[14C]半乳糖和视黄酰基磷酸的培养液中，质膜不能催化[14C]半乳糖视黄酰基磷酸的合成。本研究结果表明，视黄醇刺激[14C]半乳糖结合到分离质膜的糖脂和糖蛋白受体中。刺激的机制尚不清楚，但似乎不是一种简单的洗涤作用或视黄醇作为半乳糖视黄酰基磷酸中间体的结果。
Purified plasma membranes isolated from rat liver exhibited low levels of galactosyltransferase activity toward endogenous glycolipid and glycoprotein acceptors. The addition of retinol (0.005 mM) stimulated the transfer of [14C]galactose from UDP-[14C]galactose to endogenous glycolipid and glycoprotein acceptors of plasma membranes while higher or lower concentrations of retinol were either inhibitory or had no effect. Retinol palmitate (0.005 mM) stimulated the transfer of [14C]galactose from UDP-[14C]galactose into glycolipid but not glycoprotein acceptors of isolated plasma membranes and was inhibitory at concentrations above 0.05 mM. The addition of ATP (0.5 mM) to incubations in the absence or presence of retinol (0.025 or 0.005 mM) inhibited incorporation of [14C]galactose into glycolipid and glycoprotein acceptors. Plasma membranes did not catalyze the synthesis of [14C]galactosyl retinyl phosphate in incubations containing UDP-[14C]galactose and retinyl phosphate. The results of this study indicate that retinol stimulates incorporation of [14C]galactose into glycolipid and glycoprotein acceptors of isolated plasma membranes. The mechanism of stimulation is unknown but does not appear to be a simple detergent effect or the result of retinol acting as a galactosyl retinyl phosphate intermediate.