Abstract：
CONCLUSIONS: Overexpression of OsDJ-1C in rice improves root architecture, photosynthesis, yield and abiotic stress tolerance through modulating methylglyoxal levels, antioxidant defense, and redox homeostasis. Exposure to abiotic stresses leads to elevated methylglyoxal (MG) levels in plants, impacting seed germination and root growth. In response, the activation of NADPH-dependent aldo-keto reductase and glutathione (GSH)-dependent glyoxalase enzymes helps to regulate MG levels and reduce its toxic effects. However, detoxification may not be carried out effectively due to the limitation of GSH and NADPH in plants under stress. Recently, a novel enzyme called glyoxalase III (GLY III) has been discovered which can detoxify MG in a single step without needing GSH. To understand the physiological importance of this pathway in rice, we overexpressed the gene encoding GLYIII enzyme (OsDJ-1C) in rice. It was observed that OsDJ-1C overexpression in rice regulated MG levels under stress conditions thus, linked well with plants\' abiotic stress tolerance potential. The OsDJ-1C overexpression lines displayed better root architecture, improved photosynthesis, and reduced yield penalty compared to the WT plants under salinity, and drought stress conditions. These plants demonstrated an improved GSH/GSSG ratio, reduced level of reactive oxygen species, increased antioxidant capacity, and higher anti-glycation activity thereby indicating that the GLYIII mediated MG detoxification plays a significant role in plants\' ability to reduce the impact of abiotic stress. Furthermore, these findings imply the potential of OsDJ-1C in crop improvement programs.
摘要：
结论：在水稻中过度表达OsDJ-1C可改善根系结构，光合作用,通过调节甲基乙二醛水平的产量和非生物胁迫耐受性，抗氧化防御，和氧化还原稳态。暴露于非生物胁迫导致植物中甲基乙二醛（MG）水平升高，影响种子萌发和根系生长。作为回应,NADPH依赖性醛酮还原酶和谷胱甘肽（GSH）依赖性乙二醛酶的激活有助于调节MG水平并减少其毒性作用。然而,由于胁迫下植物中GSH和NADPH的限制，解毒可能无法有效进行。最近,已经发现了一种称为乙二醛酶III（GLYIII）的新型酶，该酶可以在不需要GSH的情况下在单个步骤中解毒MG。为了了解该途径在水稻中的生理重要性，我们在水稻中过表达了编码GLYIII酶的基因(OsDJ-1C)。观察到水稻中OsDJ-1C过表达在胁迫条件下调节MG水平，与植物的非生物胁迫耐受性潜力密切相关。OsDJ-1C过表达系表现出更好的根结构，改善光合作用，与盐度下的WT植物相比，产量损失降低，和干旱胁迫条件。这些植物表现出改善的GSH/GSSG比率，降低活性氧的水平，增加抗氧化能力，和更高的抗糖基化活性，从而表明GLYIII介导的MG解毒在植物减少非生物胁迫影响的能力中起着重要作用。此外，这些发现暗示了OsDJ-1C在作物改良计划中的潜力。
