文献类型： 外文期刊

作者： Chang, Jingjing ¹ ; Guo, Yanliang ¹ ; Li, Jiayue ¹ ; Liu, Lingling ¹ ; Liu, Jiahe ¹ ; Yuan, Li ¹ ; Wei, Chunhua ¹ ; Ma, Jianxiang ¹ ; Zhang, Yong ¹ ; Ahammed, Golam Jalal ³ ; Luan, Feishi ⁴ ; Liu, Yunqi ⁵ ; Zhang, Xian ¹ ; Li, Hao ¹ ;

作者机构： 1.Northwest A&F Univ, Coll Hort, State Key Lab Crop Stress Biol Arid Areas, Yangling 712100, Peoples R China

2.Guangdong Acad Agr Sci, Vegetable Res Inst, Key Lab New Technol Res Vegetable, Guangzhou 510640, Peoples R China

3.Henan Univ Sci & Technol, Coll Hort & Plant Protect, Luoyang 471023, Henan, Peoples R China

4.Northeast Agr Univ, Coll Hort & Landscape Architecture, Harbin 150000, Peoples R China

5.Sci Res Promot Ctr, Zhongguancun Xuyue Noninvas Microtest Technol Ind, Beijing 10080, Peoples R China

期刊名称：PLANT PHYSIOLOGY （ 影响因子：6.9； 五年影响因子：7.7 ）

ISSN： 0032-0889

年卷期： 2024 年 197 卷 2 期

页码：

收录情况： SCI

摘要： Melatonin plays a crucial role in regulating plant cold tolerance, but the mechanisms underlying signal transduction remain elusive. In this study, we discovered that overexpression of the melatonin biosynthetic gene caffeic acid O-methyltransferase1 (COMT1) enhanced watermelon (Citrullus lanatus) cold tolerance, accompanied by the accumulation of cytosolic free calcium ([Ca2+]cyt), a stimulation of Ca2+ influx, and upregulation of 4 Ca2+-permeable channel genes (CNGC2/10/17/20). Conversely, the knockout of COMT1 exhibited contrasting effects compared with its overexpression. Knocking out the 4 CNGC genes revealed that only cyclic nucleotide-gated ion channel 20 (CNGC20) mediates melatonin-induced Ca2+ influx in response to cold stimuli. CNGC20 deletion impeded watermelon callus redifferentiation, prompting us to employ a virus-induced gene silencing strategy to suppress its expression. Silencing CNGC20 compromised COMT1 overexpression-induced [Ca2+]cyt accumulation, Ca2+ influx, and watermelon cold tolerance. Yeast 2-hybrid, bimolecular fluorescence complementation, firefly luciferase complementation imaging, and pull-down assays revealed an interaction between CNGC20 and calmodulin7 (CaM7). Overexpressing CaM7 inhibited melatonin-induced [Ca2+]cyt accumulation, Ca2+ influx, and watermelon cold tolerance. Conversely, silencing CaM7 increased [Ca2+]cyt accumulation, Ca2+ influx, and cold tolerance, whereas COMT1 overexpression failed to further enhance these responses in CaM7-silenced plants, indicating the negative regulation role of CaM7 in melatonin-mediated cold responses. Overall, these findings provide insights into the molecular mechanisms underlying melatonin-enhanced plant cold tolerance via Ca2+ signaling, holding potential for breeding/engineering cold-tolerant cucurbit varieties. The interaction between cyclic nucleotide-gated ion channel 20 and calmodulin7 mediates Ca2+ signaling in Citrullus lanatus, playing a pivotal role in melatonin-induced plant tolerance to cold stress.