MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource & Environmental Sciences, Zhejiang University, Hangzhou, 310058, China.
Key Laboratory of Subtropical Soil Science and Plant Nutrition of Zhejiang Province, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
J Integr Plant Biol. 2015 Jun;57(6):550-61. doi: 10.1111/jipb.12298. Epub 2014 Dec 9.
The possible association with nitric oxide (NO) and ascorbate-glutathione (AsA-GSH) cycle in regulating aluminum (Al) tolerance of wheat (Triticum aestivum L.) was investigated using two genotypes with different Al resistance. Exposure to Al inhibited root elongation, and triggered lipid peroxidation and oxidation of AsA to dehydroascorbate and GSH to glutathione disulfide in wheat roots. Exogenous NO significantly increased endogenous NO levels, and subsequently alleviated Al-induced inhibition of root elongation and oxidation of AsA and GSH to maintain the redox molecules in the reduced form in both wheat genotypes. Under Al stress, significantly increased activities and gene transcriptional levels of ascorbate peroxidase, glutathione reductase, and dehydroascorbate reductase, were observed in the root tips of the Al-tolerant genotype Jian-864. Nitric oxide application enhanced the activity and gene transcriptional level of these enzymes in both wheat genotypes. γ-Glutamylcysteine synthetase was not significantly affected by Al or NO, but NO treatments increased the activity of glutathione peroxidase and glutathione S-transferase to a greater extent than the Al-treated wheat seedlings. Proline was significantly decreased by Al, while it was not affected by NO. These results clearly suggest that NO protects wheat root against Al-induced oxidative stress, possibly through its regulation of the AsA-GSH cycle.
使用两种具有不同耐铝性的基因型研究了一氧化氮（NO）和抗坏血酸-谷胱甘肽（AsA-GSH）循环在调节小麦耐铝性中的可能关联。铝暴露抑制根伸长，并引发小麦根中的脂质过氧化和抗坏血酸向脱氢抗坏血酸和谷胱甘肽向谷胱甘肽二硫化物的氧化。外源性 NO 显著增加内源性 NO 水平，随后缓解 Al 诱导的根伸长抑制和 AsA 和 GSH 的氧化，以维持两种小麦基因型中还原形式的氧化还原分子。在 Al 胁迫下，耐铝基因型 Jian-864 的根尖观察到抗坏血酸过氧化物酶、谷胱甘肽还原酶和脱氢抗坏血酸还原酶的活性和基因转录水平显著增加。NO 处理在两种小麦基因型中均增强了这些酶的活性和基因转录水平。γ-谷氨酰半胱氨酸合成酶不受 Al 或 NO 的显著影响，但 NO 处理比 Al 处理的小麦幼苗更能增加谷胱甘肽过氧化物酶和谷胱甘肽 S-转移酶的活性。脯氨酸被 Al 显著降低，而不受 NO 影响。这些结果清楚地表明，NO 通过调节 AsA-GSH 循环来保护小麦根免受 Al 诱导的氧化应激。
