Calcium Signaling-Linked CBF/DREB1 Gene Expression was Induced Depending on the Temperature Fluctuation in the Field: Views from the Natural Condition of Cold Acclimation
Calcium Signaling-Linked CBF/DREB1 Gene Expression was Induced Depending on the Temperature Fluctuation in the Field: Views from the Natural Condition of Cold Acclimation
复制标题
DOI：
10.1093/pcp/pcy210
复制
发表时间：
2019-02-01
影响因子：
4.9
通讯作者：
Kawamura, Yukio
中科院分区：
文献类型：
--
作者：
Hiraki, Hayato;Uemura, Matsuo;Kawamura, Yukio
环境适应性是植物生存的必要条件。虽然人们已经知道，一个简单的冷却或冷休克导致的Ca 2+信号，没有直接的证据，提供了植物使用Ca 2+信号作为第二信使在冷驯化（CA）过程中在外地。通过开发一种技术来分析Ca 2+信号，使用共聚焦低温显微镜，我们研究了Ca 2+信号在几个温度条件下，通过结合的起始温度，冷却速率和冷却时间。在根和叶细胞中，Ca 2+信号在冷却停止后迅速消失，此后在恒定低温下没有观察到Ca 2+信号。有趣的是，在2 ℃至-2 ℃的冷却制度下，在23 ℃下生长的非驯化植物几乎不显示Ca 2+信号，但在2 ℃下冷驯化的植物能够在根细胞中形成Ca 2+信号。这些结果表明，植物通过Ca 2+信号感知温度降低，同时调节对自身温度环境的温度敏感性。此外，如果温度恒定，即使在CA期间也不会诱导Ca 2+信号。然后，我们还重点研究了在田间条件下，丰富的温度波动的CA。在田间条件下的CA中，CBF/DREB 1基因的表达模式与人工CA中的表达模式明显不同。Ca 2+通道阻断剂的药理学研究表明，Ca 2+诱导的CBF/DREB 1基因表达与温度波动幅度密切相关，表明在自然条件下CA期间，Ca 2+信号调节CBF/DREB 1基因表达。
Environmental adaptability is essential for plant survival. Though it is well known that a simple cooling or cold shock leads to Ca2+ signals, direct evidence has not been provided that plants use Ca2+ signals as a second messenger in the cold acclimation (CA) process in the field. By developing a technique to analyze Ca2+ signals using confocal cryomicroscopy, we investigated Ca2+ signals under several temperature conditions by combining the start temperature, cooling rate and cooling time duration. In both root and leaf cells, Ca2+ signals rapidly disappeared after cooling stopped, and thereafter under a constant low temperature no Ca2+ signal was observed. Interestingly, under the cooling regime from 2 degrees C to -2 degrees C, non-acclimated plants grown at 23 degrees C hardly showed Ca2+ signals, but cold-acclimated plants at 2 degrees C were able to form Ca2+ signals in root cells. These findings suggest that plants sense temperature decreases with Ca2+ signals while adjusting the temperature sensitivity to their own temperature environment. Furthermore, if the temperature is constant, no Ca2+ signal is induced even during CA. Then, we also focused on the CA under field conditions, rich in temperature fluctuations. In CA under field conditions, the expression patterns of CBF/DREB1 genes were distinctly different from those in artificial CA. Pharmacological studies with Ca2+ channel blockers showed that the Ca2+-induced expression of CBF/DREB1 genes was closely correlated with the amplitude of temperature fluctuation, suggesting that Ca2+ signals regulate CBF/DREB1 gene expression during CA under natural conditions.