Translational regulation of mammalian ornithine decarboxylase by polyamines.
Translational regulation of mammalian ornithine decarboxylase by polyamines.
复制标题
DOI：
--
复制
发表时间：
1985-12
期刊：
影响因子：
--
通讯作者：
C. Kahana;D. Nathans
中科院分区：
文献类型：
--
作者：
C. Kahana;D. Nathans
鸟氨酸脱羧酶是哺乳动物细胞中多胺生物合成的第一个酶和限速酶，催化腐胺的形成。这种酶受到高度调节，如细胞生长期间其mRNA和蛋白质的快速变化所示。在这里，我们报告说，鸟氨酸脱羧酶在翻译水平上的多胺在二氟甲基鸟氨酸耐药小鼠骨髓瘤细胞，过度生产的酶，由于扩增的鸟氨酸脱羧酶基因的调节。当这些细胞暴露于腐胺或其他多胺时，通过脉冲标记法测定，鸟氨酸脱羧酶的合成速率迅速而特异性地降低。既不影响鸟氨酸脱羧酶mRNA的细胞含量，也不影响鸟氨酸脱羧酶蛋白的半衰期。我们的研究结果表明，多胺负调节鸟氨酸脱羧酶mRNA的翻译，从而控制自己的合成。
Ornithine decarboxylase, which catalyses the formation of putrescine, is the first and rate-limiting enzyme in the biosynthesis of polyamines in mammalian cells. The enzyme is highly regulated, as indicated by rapid changes in its mRNA and protein during cell growth. Here we report that ornithine decarboxylase is regulated at the translational level by polyamines in difluoromethylornithine-resistant mouse myeloma cells that overproduce the enzyme due to amplification of an ornithine decarboxylase gene. When such cells are exposed to putrescine or other polyamines, there is a rapid and specific decrease in the rate of synthesis of ornithine decarboxylase, assayed by pulse-labeling. Neither the cellular content of ornithine decarboxylase mRNA nor the half-life of ornithine decarboxylase protein is affected. Our results indicate that polyamines negatively regulate the translation of ornithine decarboxylase mRNA, thereby controlling their own synthesis.