Rapid regulation of L-type pyruvate kinase mRNA by fructose in diabetic rat liver.
Rapid regulation of L-type pyruvate kinase mRNA by fructose in diabetic rat liver.
复制标题
果糖对糖尿病大鼠肝脏中 L 型丙酮酸激酶 mRNA 的快速调节。
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
T. Tanaka
中科院分区：
文献类型：
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作者：
H. Inoue;T. Noguchi;T. Tanaka
用克隆的cDNA探针研究了果糖对糖尿病大鼠肝脏L型丙酮酸激酶mRNA的诱导作用。果糖喂养导致L型酶mRNA水平在1至3天后增加5至6倍。这些变化与该酶的可翻译mRNA水平的变化大致成比例。果糖饲喂后2 h内，细胞L型酶mRNA水平显著升高，8h后达到最大值。日粮甘油也显着增加L型mRNA水平。这些变化基本上是由于胞质mRNA的变化。细胞总RNA的北方印迹分析显示，在果糖诱导过程中，分子大小为2.1和3.6的两种L型酶mRNA种类成比例地增加。这两种mRNA形式存在于免疫纯化的L型酶mRNA中，并在体外定向合成L型亚基;因此它们是功能成熟的形式。相比之下，核RNA的分析表明，五个推定的前体RNA物种的酶，长达9.4酶的长度，在果糖喂养的大鼠的肝脏，而没有带的RNA物种被发现在控制肝脏的细胞核。这些RNA种类的条带数量和强度的变化，果糖喂养后的总细胞L-型酶mRNA序列的水平的变化之前。这些结果表明，膳食果糖通过作用于细胞核水平而导致L型丙酮酸激酶mRNA序列水平的快速增加。
The effect of fructose on the induction of L-type pyruvate kinase mRNA in diabetic rat liver was studied by using a cloned cDNA probe. Fructose feeding resulted in a 5- to 6-fold increase in the L-type enzyme mRNA level after 1 to 3 days. These changes were approximately proportional to the changes in the level of translatable mRNA of this enzyme. A significant increase in total cellular L-type enzyme mRNA level was observed within 2 h after fructose feeding and the level reached a maximum after 8 h. Dietary glycerol also markedly increased the L-type mRNA level. These alterations were essentially due to the changes in the cytosolic mRNA. Northern blot analysis of total cellular RNA revealed that two L-type enzyme mRNA species with molecular sizes of 2.1 and 3.6 kilobases were proportionally increased during the fructose induction. The two mRNA forms were found in immunopurified L-type enzyme mRNA and directed synthesis of the L-type subunit in vitro; they are therefore functional mature forms. In contrast, analysis of nuclear RNA showed five putative precursor RNA species for the enzyme, up to 9.4 kilobases in length, in the liver of fructose-fed rats, while no band of the RNA species was found in the nuclei of control liver. The changes in the number of bands of these RNA species and their intensities after fructose feeding preceded the changes in the level of total cellular L-type enzyme mRNA sequences. These results indicate that dietary fructose causes a rapid increase in the level of L-type pyruvate kinase mRNA sequences by acting at the nuclear level.