Stabilization of a specific nuclear mRNA precursor by thyroid hormone.
Stabilization of a specific nuclear mRNA precursor by thyroid hormone.
复制标题
甲状腺激素对特定核 mRNA 前体的稳定作用。
DOI：
10.1128/mcb.5.10.2642-2646.1985
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发表时间：
1985
影响因子：
5.3
通讯作者：
Towle,HC
中科院分区：
文献类型：
--
作者：
Narayan,P;Towle,HC
研究了大鼠甲状腺激素反应基因（指定为斑点14）的调节。对甲状腺功能减退大鼠给予3，5，3 ′-三碘-L-甲状腺原氨酸（T3）后，该基因在肝脏中的表达迅速（<10分钟）并显著（>10倍）改变（P. Narayan，C. W. Liaw和H. C. Towle，Proc. Natl. Acad. Sci. USA 81：4687-4691，1984）。为了研究T3作用于诱导这种肝脏mRNA的细胞位点，我们对斑点14 mRNA和核前体RNA的相对水平以及旨在改变大鼠甲状腺状态的治疗后的基因转录速率进行了平行测量。与甲状腺功能减退对照组相比，甲状腺功能正常动物的mRNA和核前体的相对水平升高约5至6倍，甲状腺功能亢进动物升高约9至12倍。然而，在斑点14基因转录速率中仅检测到约1.5倍的小差异。甲状腺功能减退动物单次注射T3后，在30 min时检测到转录率的小而短暂的上升。然而，在治疗的前4 h，斑点14 mRNA和核前体RNA的水平增加得更显着。在这两种情况下，基因转录速率的变化不能解释mRNA水平的变化。因此，T3对spot 14基因调控的主要位点是在转录后水平。在核前体和mRNA水平中观察到的比例变化表明，对照位点处于斑点14 mRNA的核前体RNA的稳定性水平。
The regulation of a thyroid hormone-responsive gene in rats, designated spot 14, was explored. The expression of this gene in liver is rapidly (<10 min) and markedly (>10-fold) altered by the administration of 3,5,3′-triiodo-L-thyronine (T3) to hypothyroid rats (P. Narayan, C. W. Liaw, and H. C. Towle, Proc. Natl. Acad. Sci. USA 81:4687–4691, 1984). To investigate the cellular site at which T3acts to induce this hepatic mRNA, we made parallel measurements of the relative levels of spot 14 mRNA and nuclear precursor RNA and of the rate of gene transcription after treatments designed to alter the thyroid status of rats. The relative levels of both the mRNA and nuclear precursor were elevated roughly 5- to 6-fold in euthyroid animals and 9- to 12-fold in hyperthyroid animals over those in hypothyroid controls. However, only a small difference of approximately 1.5-fold was detected in the rate of spot 14 gene transcription. After a single injection of T3into hypothyroid animals, a small and transient rise in the transcription rate was detected at 30 min. However, the levels of spot 14 mRNA and nuclear precursor RNA increased much more dramatically throughout the first 4 h of treatment. In both cases, changes in the rate of gene transcription were not capable of accounting for the alterations observed in mRNA levels. Thus, the major site of spot 14 gene regulation by T3is at a posttranscriptional level. The proportional changes observed in the nuclear precursor and mRNA levels suggest that the site of control is at the level of stability of the nuclear precursor RNA for spot 14 mRNA.