United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo, Japan.
Center for Bioscience Research and Education, Utsunomiya University, Utsunomiya, Japan.
PLoS One. 2024 Jul 22;19(7):e0307393. doi: 10.1371/journal.pone.0307393. eCollection 2024.
Global warming has led to the expansion of arid lands and more frequent droughts, which are the largest cause of global food production losses. In our previous study, we developed TaPYLox wheat overexpressing the plant hormone abscisic acid (ABA) receptor, which is important for the drought stress response in plants. TaPYLox showed resistance to drought stress and acquired water-saving traits that enable efficient grain production with less water use. In this study, we used TaPYLox to identify ABA-dependent and -independent metabolites in response to drought stress. We compared the variation of metabolites in wheat under well-watered, ABA treatment, and drought stress conditions using the ABA-sensitive TaPYLox line and control lines. The results showed that tagatose and L-serine were ABA-dependently regulated metabolites, because their stress-induced accumulation was increased by ABA treatment in TaPYLox. In contrast, L-valine, L-leucine, and DL-isoleucine, which are classified as branched chain amino acids, were not increased by ABA treatment in TaPYLox, suggesting that they are metabolites regulated in an ABA-independent manner. Interestingly, the accumulation of L-valine, L-leucine, and DL-isoleucine was suppressed in drought-tolerant TaPYLox under drought stress, suggesting that drought-tolerant wheat might be low in these amino acids. 3-dehydroshikimic acid and α-ketoglutaric acid were decreased by drought stress in an ABA-independent manner. In this study, we have succeeded in identifying metabolites that are regulated by drought stress in an ABA-dependent and -independent manner. The findings of this study should be useful for future breeding of drought-tolerant wheat.
全球变暖导致干旱土地的扩张和更频繁的干旱，这是全球粮食生产损失的最大原因。在我们之前的研究中，我们开发了过表达植物激素脱落酸（ABA）受体的 TaPYLox 小麦，ABA 受体对植物的干旱胁迫反应很重要。TaPYLox 表现出对干旱胁迫的抗性，并获得了节水特性，能够在较少用水的情况下实现高效的谷物生产。在这项研究中，我们使用 TaPYLox 来鉴定对干旱胁迫的 ABA 依赖和非依赖代谢物。我们使用 ABA 敏感的 TaPYLox 系和对照系比较了在充分浇水、ABA 处理和干旱胁迫条件下小麦中代谢物的变化。结果表明，塔格糖和 L-丝氨酸是 ABA 依赖调节的代谢物，因为它们在 TaPYLox 中的应激诱导积累是由 ABA 处理增加的。相比之下，L-缬氨酸、L-亮氨酸和 DL-异亮氨酸，它们被归类为支链氨基酸，在 TaPYLox 中没有被 ABA 处理增加，这表明它们是 ABA 非依赖调节的代谢物。有趣的是，在干旱胁迫下，耐旱性 TaPYLox 中 L-缬氨酸、L-亮氨酸和 DL-异亮氨酸的积累受到抑制，这表明耐旱性小麦可能这些氨基酸含量较低。3-脱氢莽草酸和α-酮戊二酸以 ABA 非依赖的方式因干旱胁迫而减少。在这项研究中，我们成功地鉴定了 ABA 依赖和非依赖调节的受干旱胁迫调控的代谢物。本研究的结果对于未来耐旱小麦的培育应该是有用的。
