Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin, Xiqing, China.
School of Basic Medical Sciences, Fudan University, Shanghai, Yangpu, China.
Plant Signal Behav. 2022 Dec 31;17(1):2065114. doi: 10.1080/15592324.2022.2065114.
Anthropogenic activities cause heavy metal pollution, such as cadmium (Cd). Na/H antiporter (NHX1) transgenic duckweed showed Cd tolerance in our previous study, and the signal mechanism needs to be explored. As an important signal molecule, nitric oxide (NO) is involved in a number of functions under abiotic stress response. This study analyzed the levels of endogenous NO in wild-type (WT) duckweed and NHX1 duckweed under Cd treatment. The results showed that after 24 h Cd treatment, the endogenous NO level of WT duckweed decreased, which was significantly lower than that in NHX1 duckweed. Studies have proved that NHX1 influences pH. The level of NO in this study has been investigated at different pH. The NO level was the highest in the duckweed cultured with pH 5.3. Nitrate reductase gene expression was down-regulated and NO synthesis was decreased under Cd stress in WT duckweed. This study showed that NO level has been modified in NHX1 duckweed, which could be influcened by pH.
人为活动导致重金属污染，如镉（Cd）。在我们之前的研究中，Na/H 反向转运蛋白（NHX1）转基因浮萍表现出对 Cd 的耐受性，但其信号机制仍需探索。一氧化氮（NO）作为一种重要的信号分子，参与了非生物胁迫响应下的多种功能。本研究分析了 Cd 处理下野生型（WT）浮萍和 NHX1 浮萍内源 NO 的水平。结果表明，24 h Cd 处理后，WT 浮萍内源 NO 水平下降，明显低于 NHX1 浮萍。研究证明 NHX1 影响 pH 值。本研究还在不同 pH 值下对 NO 水平进行了调查。在 pH 值为 5.3 的条件下，浮萍的 NO 水平最高。在 WT 浮萍中，硝酸盐还原酶基因表达下调，NO 合成减少，导致 Cd 胁迫。本研究表明，NHX1 浮萍中 NO 水平发生了修饰，这可能受到 pH 值的影响。
