CAMP STIMULATES TRANSCRIPTION OF THE GENE FOR CYTOSOLIC PHOSPHOENOLPYRUVATE CARBOXYKINASE IN RAT-LIVER NUCLEI
CAMP STIMULATES TRANSCRIPTION OF THE GENE FOR CYTOSOLIC PHOSPHOENOLPYRUVATE CARBOXYKINASE IN RAT-LIVER NUCLEI
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DOI：
10.1073/pnas.79.17.5137
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发表时间：
1982-01-01
期刊：
影响因子：
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通讯作者：
MEISNER, HM
中科院分区：
文献类型：
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作者：
LAMERS, WH;HANSON, RW;MEISNER, HM
通过使用克隆的 c[互补]DNA 探针，研究了饥饿、葡萄糖补给、二丁酰 cAMP 和地塞米松对大鼠肝细胞质中磷酸烯醇丙酮酸羧激酶 (GTP) [GTP：草酰乙酸羧基裂解酶（转磷酸化），EC 4.1.1.32] 基因表达的影响。从饥饿大鼠中分离出的肝细胞核中磷酸烯醇丙酮酸羧激酶基因的转录率在重新喂食葡萄糖后迅速下降。给喂食葡萄糖的动物施用二丁酰 cAMP，磷酸烯醇丙酮酸羧激酶基因转录率在 20 分钟内增加了 7 倍。胞浆中的磷酸烯醇丙酮酸羧激酶 mRNA 长 2.8 kb，而肝细胞核含有 4 个前体 RNA，长度可达 6.5 kb。给饥饿的大鼠喂食葡萄糖会迅速降低细胞核和细胞质中酶 mRNA 的序列丰度。在重新喂食葡萄糖后的第一个 20 分钟内，胞质磷酸烯醇丙酮酸羧激酶 mRNA 减少，随后酶 mRNA 短暂增加。给予葡萄糖喂养的饥饿动物二丁酰cAMP可在30分钟内使磷酸烯醇丙酮酸羧激酶的核RNA前体浓度增加5至8倍，并在60分钟内诱导胞质酶的mRNA。 cAMP 通过增加基因转录速率来诱导磷酸烯醇丙酮酸羧激酶 mRNA。
The effects of starvation, glucose refeeding, dibutyryl cAMP, and dexamethasone on expression of the gene for phosphoenolpyruvate carboxykinase (GTP) [GTP:oxaloacetate carboxy-lyase (transphosphorylating), EC 4.1.1.32] from rat liver cytosol was studied by using a cloned c[complementary]DNA probe. The rate of transcription of the gene for phosphoenolpyruvate carboxykinase in hepatic nuclei isolated from starved rats decreased rapidly after refeeding with glucose. Administration of dibutyryl cAMP to glucose-refed animals increased the rate of phosphoenolpyruvate carboxykinase gene transcription 7-fold within 20 min. Phosphoenolpyruvate carboxykinase mRNA in the cytosol is 2.8 kilobases long whereas liver nuclei contain 4 precursor RNA species that are up to 6.5 kilobases long. Feeding glucose to starved rats rapidly decreased the sequence abundance of enzyme mRNA in both nuclei and cytosol. The decrease in cytosolic phosphoenolpyruvate carboxykinase mRNA was preceded by a transient increase in enzyme mRNA over the 1st 20 min after glucose refeeding. Administration of dibutyryl cAMP to glucose-refed starved animals increased the concentration of the nuclear RNA precursors of phosphoenolpyruvate carboxykinase 5- to 8-fold within 30 min and induced the mRNA for the cytosolic enzyme over a period of 60 min. cAMP induces phosphoenolpyruvate carboxykinase mRNA by increasing the rate of gene transcription.