Retinol-binding protein messenger RNA levels in the liver and in extrahepatic tissues of the rat.
Retinol-binding protein messenger RNA levels in the liver and in extrahepatic tissues of the rat.
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DOI：
10.1016/s0022-2275(20)38843-x
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发表时间：
1986-02
影响因子：
6.5
通讯作者：
D. Soprano;K. Soprano;D. Goodman
中科院分区：
文献类型：
--
作者：
D. Soprano;K. Soprano;D. Goodman
应用视黄醇结合蛋白(RBP)基因克隆，检测视黄醇状态对肝脏RBP基因表达水平的影响，探讨肝外组织中是否含有RBP基因。在第一系列实验中，从正常、视黄醇耗竭和视黄醇重复使用的大鼠的肝脏中提取聚(A+)RNA，并通过Northern印迹和RNA斑点印迹分析检测这些样品中RBP mRNA的水平。3组大鼠肝脏中RBP基因表达水平无明显差异。这些发现证实和扩展了先前的研究，这些研究表明视黄醇不会改变RBP的体内合成速度或RBP mRNA的可翻译水平。在第二系列实验中，RBP克隆被用来通过Northern印迹分析从12个不同组织中分离的聚(A+)RNA来检测RBP mRNA。我们发现，与肝脏一样，许多肝外组织也含有RBP mRNA。肾脏的RBP mRNA含量是肝脏的5-10%，肺、脾、脑、胃、心脏和骨骼肌的含量是肝脏的1-3%。用兔网织红细胞裂解物翻译肾脏多聚(A+)RNA，并用抗RBP抗血清进行免疫沉淀，得到一条与肝脏前RBP相同大小的蛋白条带。这些数据表明，RBP在许多肝外组织中合成。这种肝外合成的RBP可能在将视黄醇从这些组织循环回肝脏或其他靶器官的过程中发挥作用。
A retinol-binding protein (RBP) cDNA clone was used to examine the effect of retinol status on the level of RBP mRNA in the liver, and to explore whether extrahepatic tissues contain RBP mRNA. In the first series of experiments, poly(A+) RNA was isolated from the livers of normal, retinol-depleted, and retinol-repleted rats and the levels of RBP mRNA in these samples were determined by both Northern blot and RNA Dot blot analyses. The levels of RBP mRNA in liver were similar in all three groups of rats. These findings confirm and extend previous studies which showed that retinol did not alter the in vivo rate of RBP synthesis or the translatable levels of RBP mRNA. In a second series of experiments, the RBP cDNA clone was used to survey poly (A+) RNA isolated from 12 different rat tissues for RBP mRNA by Northern blot analysis. We found that, along with the liver, many extrahepatic tissues contained RBP mRNA. Kidney contained RBP mRNA at a level of 5-10% of that of the liver, and the lungs, spleen, brain, stomach, heart, and skeletal muscle contained 1-3% of that of the liver. Translation of kidney poly (A+) RNA in rabbit reticulocyte lysates and immunoprecipitation of the translation products with anti-RBP antiserum resulted in a protein band of the same size as liver preRBP. These data suggest that RBP is synthesized in many extrahepatic tissues. It is possible that this extra-hepatically synthesized RBP may function in the recycling of retinol from these tissues back to the liver or to other target organs.