Department of Pomology, College of Horticulture, South China Agricultural University, Guangzhou 510642, China.
Centre of the Region Haná for Biotechnological and Agricultural Research, Department of Cell Biology, Faculty of Science, Palacký University, 783 71 Olomouc, Czech Republic.
Int J Mol Sci. 2020 Dec 7;21(23):9326. doi: 10.3390/ijms21239326.
Banana is one of the most important food and fruit crops in the world and its growth is ceasing at 10-17 °C. However, the mechanisms determining the tolerance of banana to mild (>15 °C) and moderate chilling (10-15 °C) are elusive. Furthermore, the biochemical controls over the photosynthesis in tropical plant species at low temperatures above 10 °C is not well understood. The purpose of this research was to reveal the response of chilling-sensitive banana to mild (16 °C) and moderate chilling stress (10 °C) at the molecular (transcripts, proteins) and physiological levels. The results showed different transcriptome responses between mild and moderate chilling stresses, especially in pathways of plant hormone signal transduction, ABC transporters, ubiquinone, and other terpenoid-quinone biosynthesis. Interestingly, functions related to carbon fixation were assigned preferentially to upregulated genes/proteins, while photosynthesis and photosynthesis-antenna proteins were downregulated at 10 °C, as revealed by both digital gene expression and proteomic analysis. These results were confirmed by qPCR and immunofluorescence labeling methods. Conclusion: Banana responded to the mild chilling stress dramatically at the molecular level. To compensate for the decreased photosynthesis efficiency caused by mild and moderate chilling stresses, banana accelerated its carbon fixation, mainly through upregulation of phosphoenolpyruvate carboxylases.
香蕉是世界上最重要的粮食和水果作物之一，其生长在 10-17°C 时会停止。然而，决定香蕉对轻度（>15°C）和中度冷藏（10-15°C）的耐受性的机制尚不清楚。此外，在 10°C 以上的低温下，热带植物物种光合作用的生化控制也没有得到很好的理解。本研究的目的是揭示对低温敏感的香蕉在分子（转录本、蛋白质）和生理水平上对轻度（16°C）和中度冷藏胁迫的反应。结果表明，轻度和中度冷藏胁迫之间存在不同的转录组反应，特别是在植物激素信号转导、ABC 转运蛋白、泛醌和其他萜类-醌生物合成途径中。有趣的是，与碳固定相关的功能被优先分配给上调的基因/蛋白质，而光合作用和光合作用天线蛋白在 10°C 时被下调，这一点通过数字基因表达和蛋白质组学分析都得到了证实。这些结果通过 qPCR 和免疫荧光标记方法得到了验证。结论：香蕉在分子水平上对轻度冷藏胁迫有显著反应。为了弥补轻度和中度冷藏胁迫导致的光合作用效率降低，香蕉加速了其碳固定，主要通过上调磷酸烯醇丙酮酸羧化酶。
