Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Pampulha, Belo Horizonte, MG, Brazil.
Departamento de Ciências Biológicas, Universidade de São Paulo/ESALQ, Piracicaba, SP, Brazil.
Nitric Oxide. 2018 Jun 1;76:164-173. doi: 10.1016/j.niox.2017.09.008. Epub 2017 Sep 28.
High salinity greatly impacts agriculture, particularly in tomato (Solanum lycopersicum), a crop that is a model to study this abiotic stress. This work investigated whether hydrogen sulfide (HS) acts upstream or downstream of nitric oxide (NO) in the signaling cascade during tomato response to salt stress. An NO-donor incremented HS levels by 12-18.9% while an HS-donor yielded 10% more NO in roots. The NO accumulated in roots one-hour after NaCl treatment while HS accumulation started two-hour later. The NO stimulated HS accumulation in roots/leaves, but not the opposite (i.e HS was unable to stimulate NO accumulation) two-hour post NaCl treatment. Also, NO accumulation was accompanied by an increment of transcript levels of genes that encode for HS-synthesizing enzymes. Our results indicate that HS acts downstream of NO in the mitigation of oxidative stress, which helps tomato plants to tolerate high salinity.
高盐度对农业有很大影响，尤其是在番茄（Solanum lycopersicum）中，番茄是研究这种非生物胁迫的模式作物。本研究探讨了在番茄响应盐胁迫过程中，硫化氢（HS）是否在一氧化氮（NO）信号级联中上游或下游起作用。NO 供体使 HS 水平增加了 12-18.9%，而 HS 供体使根中的 NO 增加了 10%。NO 在 NaCl 处理后一小时在根中积累，而 HS 积累则在两小时后开始。NO 刺激根/叶中 HS 的积累，但反之则不行（即在 NaCl 处理后两小时，HS 不能刺激 NO 的积累）。此外，NO 的积累伴随着编码 HS 合成酶的基因转录水平的增加。我们的结果表明，在缓解氧化应激方面，HS 位于 NO 的下游，这有助于番茄植物耐受高盐度。
