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. (31st October 2018)

• Record Type: Journal Article
• Authors: Hiraki, Hayato; Uemura, Matsuo; Kawamura, Yukio
• Is Part Of: Plant & cell physiology. Volume 60:Number 2(2019)
• Page Start: 303
• Page End: 317
• Publication Date: 2018-10-31
• Subjects: Arabidopsis thaliana -- Calcium signal -- Cold acclimation -- Cold perception -- Field -- Temperature fluctuation -- Yellow Cameleon 3.60 (YC3.60); Plant physiology -- Periodicals; Microbiology -- Periodicals; Cytology -- Periodicals; Cell Physiology -- Periodicals; Plant Physiological Phenomena -- Periodicals; Cytology; Microbiology; Plant physiology; Periodicals; 571.205
• DOI: 10.1093/pcp/pcy210
• Languages: English
• ISSNs: 0032-0781

Abstract

Abstract: Environmental adaptability is essential for plant survival. Though it is well known that a simple cooling or cold shock leads to Ca 2+ signals, direct evidence has not been provided that plants use Ca 2+ signals as a second messenger in the cold acclimation (CA) process in the field. By developing a technique to analyze Ca 2+ signals using confocal cryomicroscopy, we investigated Ca 2+ signals under several temperature conditions by combining the start temperature, cooling rate and cooling time duration. In both root and leaf cells, Ca 2+ signals rapidly disappeared after cooling stopped, and thereafter under a constant low temperature no Ca 2+ signal was observed. Interestingly, under the cooling regime from 2�C to −2�C, non-acclimated plants grown at 23�C hardly showed Ca 2+ signals, but cold-acclimated plants at 2�C were able to form Ca 2+ signals in root cells. These findings suggest that plants sense temperature decreases with Ca 2+ signals while adjusting the temperature sensitivity to their own temperature environment. Furthermore, if the temperature is constant, no Ca 2+ 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 Ca 2+ channel blockers showed that the Ca 2+ -induced expression of CBF/DREB1 genes was closely correlated with the amplitude of temperature fluctuation, suggesting that Ca 2+ signals regulate CBF/DREB1 gene expression during CA under natural conditions.