Low temperature induction of Arabidopsis CBF1, 2, and 3 is gated by the circadian clock
Low temperature induction of Arabidopsis CBF1, 2, and 3 is gated by the circadian clock
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DOI：
10.1104/pp.104.058354
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发表时间：
2005-03-01
期刊：
影响因子：
7.4
通讯作者：
Thomashow, ME
中科院分区：
文献类型：
--
作者：
Fowler, SG;Cook, D;Thomashow, ME
将拟南芥（拟南芥）植物暴露于低温导致CBF 1、2和3（CBF 1 -3;也分别称为DREB 1B、C和A）的快速诱导，CBF 1 - 3编码转录激活因子，其诱导一系列基因的表达，所述基因增加植物的冷冻和低温耐受性。最近，它已被证明，CBF 3转录本和某些CBF调节基因的基础水平表现出昼夜节律循环。在此，我们进一步探讨了生物钟对CBF 1 -3的调节作用。结果表明，CBF 1 -3转录物在低温下的积累程度取决于植物暴露于低温的时间，这是由生物钟调节的。最高和最低水平的冷诱导CBF 1 -3转录积累分别发生在主观黎明后4和16 h。分析CBF 2。启动子-报告基因融合表明，这种控制包括转录调控。此外，冷反应。与CBF 1 -3平行冷诱导的基因RAV 1和ZAT 12也受到昼夜节律调节。然而，尽管冷诱导的RAV 1转录物积累的最高水平与CBF 1 -3转录物发生在一天中的相同时间，但ZAT 12的最高水平处于相反的阶段，即冷诱导的ZAT 12转录物积累的最高水平发生在主观黎明后16小时。这些结果表明，CBF 1 -3，RAV 1和2 AT 12的冷诱导表达是由昼夜节律钟门控的，并表明这种调节可能通过至少两个不相同的（尽管可能重叠）信号通路发生。
Exposing Arabidopsis (Arabidopis thaliana) plants to low temperature results in rapid induction of CBF1, 2, and 3 (CBF1-3; also known as DREB1B, C, and A, respectively), which encode transcriptional activators that induce expression of a battery of genes that increase plant freezing and chilling, tolerance. Recently,,it has been shown that, basal levels of CBF3 transcripts and those of certain CBF-regulated genes exhibit circadian cycling. Here, we further explored the regulation of CBF1-3 by the circadian clock. The results indicated that the extent to which CBF1-3 transcripts accumulated in response to low temperature was dependent on the time of day that the plants were exposed to low temperature and that this was regulated by the circadian clock. The highest and lowest levels of cold-induced CBF1-3 transcript accumulation occurred at 4 and 16 h after subjective dawn, respectively. An analysis of CBF2. promoter-reporter gene fusions indicated that this control included transcriptional regulation. In addition, the cold responsiveness. of RAV1 and ZAT12, genes that are cold induced in parallel with CBF1-3, was also subject to circadian regulation. However, whereas the maximum level of cold-induced RAV1 transcript accumulation occurred at the same time of day as did CBF1-3 transcripts, that of ZAT12 Was in reverse phase, i.e. the highest level of cold-induced ZAT12 transcript accumulation occurred 16 h after subjective dawn. These results indicate that cold-induced expression of CBF1-3, RAV1, and 2 AT12 is gated by the circadian clock and suggest that this regulation likely occurs through at least two nonidentical (though potentially overlapping) signaling pathways.