Drought is a major threat to wheat growth and crop productivity. However, there has been only limited success in developing drought-hardy cultivars. This lack of progress is due, at least in part, to a lack of understanding of the molecular mechanisms of drought tolerance in wheat. Here, we evaluated the potential role of three cytosolic glyceraldehyde-3-phosphate dehydrogenases (TaGAPC2/5/6) under drought stress in wheat and Arabidopsis. We found that TaGAPC2/5/6 all positively responded to drought stress via reactive oxygen species (ROS) scavenging and stomatal movement. The results of yeast co-transformation and electrophoretic mobility shift assay showed that TaWRKY33 acted as a direct regulator of TaGAPC2/5/6 genes. The dual luciferase reporter assay indicated that TaWRKY33 positively activated the expression of TaGAPC2/5/6. The results of bimolecular fluorescence complementation and yeast two-hybrid system demonstrated that TaGAPC2/5/6 interacted with phospholipase Dδ (PLDδ). We then demonstrated that TaGAPC2/5/6 positively promoted the activity of TaPLDδ in vitro and in vivo. Furthermore, lower PLDδ activity in RNAi wheat could lead to less PA accumulation, causing higher stomatal aperture sizes under drought stress. In summary, our results establish a new positive regulatory mechanism of TaGAPCs which helps wheat fine-tune their drought responses.

中文翻译：

---

小麦中的胞质甘油醛-3-磷酸脱氢酶2/5/6通过气孔运动和清除活性氧来提高抗旱性。

干旱是对小麦生长和作物生产力的主要威胁。但是，在开发抗旱品种方面仅取得了有限的成功。缺乏这种进展至少部分是由于对小麦耐旱性的分子机制缺乏了解。在这里，我们评估了三种干旱和干旱下小麦和拟南芥中三种胞质甘油醛-3-磷酸脱氢酶（TaGAPC2 / 5/6）的潜在作用。我们发现TaGAPC2 / 5/6都通过活性氧（ROS）清除和气孔运动对干旱胁迫做出了积极反应。酵母共转化和电泳迁移率迁移分析的结果表明，TaWRKY33充当TaGAPC2 / 5/6基因的直接调节子。双重荧光素酶报告基因测定表明，TaWRKY33阳性激活了TaGAPC2 / 5/6的表达。双分子荧光互补和酵母双杂交系统的结果表明，TaGAPC2 / 5/6与磷脂酶Dδ（PLDδ）相互作用。然后，我们证明了TaGAPC2 / 5/6在体外和体内均可积极促进TaPLDδ的活性。此外，RNAi小麦中较低的PLDδ活性可能导致较少的PA积累，从而在干旱胁迫下导致较高的气孔孔径。总而言之，我们的结果建立了TaGAPC的新的积极调控机制，该机制有助于小麦微调其干旱响应。在干旱胁迫下导致较高的气孔孔径。总而言之，我们的结果建立了TaGAPC的新的积极调控机制，该机制有助于小麦微调其干旱响应。在干旱胁迫下导致较高的气孔孔径。总而言之，我们的结果建立了TaGAPC的新的积极调控机制，该机制有助于小麦微调其干旱响应。