Park Sang-Hyun, Lee Bok-Rye, La Van Hien, Mamun Md Al, Bae Dong-Won, Kim Tae-Hwan
Department of Animal Science, Institute of Agricultural Science and Technology, College of Agriculture & Life Science, Chonnam National University, Gwangju 61186, Korea.
Department of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry, Thai Nguten 24000, Vietnam.
Plants (Basel). 2021 Mar 23;10(3):610. doi: 10.3390/plants10030610.
The aim of this study was to characterize hormonal crosstalk with the sugar signaling and metabolic pathway based on a time course analysis of drought intensity. Drought intensity-responsive changes in the assimilation of newly fixed carbon (C) into soluble sugar, the content of sugar and starch, and expression of genes involved in carbohydrate metabolism were interpreted as being linked to endogenous abscisic acid (ABA) and salicylic acid (SA) levels and their signaling genes. The ABA and SA levels in the drought-stressed leaves increased together during the early drought period (days 0-6), and additional ABA accumulation occurred with depressed SA during the late period (days 6-14). Although drought treatment decreased the assimilation of newly fixed C into soluble sugar, representing a 59.9%, 33.1%, and 62.9% reduction in C-glucose, C-fructose, and C-sucrose on day 14, respectively, the drought-responsive accumulation of soluble sugars was significant. During the early period, the drought-responsive accumulation of hexose and sucrose was concurrent with the upregulated expression of (, which, in turn, occurred parallel to the upregulation of ABA synthesis gene () and SA-related genes ( () and ()). During the late period, hexose accumulation, sucrose phloem loading, and starch degradation were dominant, with a highly enhanced expression of the starch degradation-related genes () and (), which were concomitant with the parallel enhancement of () and () expression in an ABA-dependent manner. These results indicate that the drought-responsive accumulation of sugars (especially SA-mediated sucrose accumulation) is part of the acclamatory process during the early period. Conversely, ABA-responsive hexose accumulation and sucrose phloem loading represent severe drought symptoms during the late drought period.
本研究的目的是基于干旱强度的时间进程分析，表征激素与糖信号和代谢途径之间的相互作用。新固定碳（C）同化为可溶性糖、糖和淀粉含量以及参与碳水化合物代谢的基因表达中干旱强度响应性变化被解释为与内源脱落酸（ABA）和水杨酸（SA）水平及其信号基因有关。在干旱初期（第0 - 6天），干旱胁迫叶片中的ABA和SA水平共同升高，而在后期（第6 - 14天），随着SA水平降低，ABA进一步积累。尽管干旱处理降低了新固定碳同化为可溶性糖的量，在第14天，C - 葡萄糖、C - 果糖和C - 蔗糖分别减少了59.9%、33.1%和62.9%，但干旱响应性可溶性糖积累显著。在早期，己糖和蔗糖的干旱响应性积累与 （此处原文缺失基因名称） 的上调表达同时发生，而这又与ABA合成基因 （此处原文缺失基因名称） 和SA相关基因 （此处原文缺失基因名称） 和 （此处原文缺失基因名称） 的上调平行发生。在后期，己糖积累、蔗糖韧皮部装载和淀粉降解占主导，淀粉降解相关基因 （此处原文缺失基因名称） 和 （此处原文缺失基因名称） 的表达高度增强，这与 （此处原文缺失基因名称） 和 （此处原文缺失基因名称） 表达以ABA依赖方式平行增强相伴。这些结果表明，干旱响应性糖积累（尤其是SA介导的蔗糖积累）是早期适应过程的一部分。相反，ABA响应性己糖积累和蔗糖韧皮部装载代表后期干旱阶段的严重干旱症状。
