Abstract Plants treated with metals better fend off infection by pathogens. This activity is mediated, at least in part, by the activation of the salicylic acid (SA) signaling pathway. Previous work in our laboratory demonstrated that silicon (Si) could alleviate copper (Cu) toxicity stress in Nicotiana tabacum. However, how Si affected expression of genes involved in SA biosynthesis and signaling in N. tabacum under Cu stress was unclear. Therefore, we investigated this at two time points. Roots of plants treated with Cu toxicity for one week exhibited increased transcript levels for Isochorismate Synthase1, a gene encoding a key enzyme involved in SA biosynthesis and the addition of Si further enhanced expression. Microarray analysis identified a number of disease defense-associated genes up-regulated in N. tabacum roots after one week of Cu toxicity treatment and further increased when plants were also supplemented with Si. However, the effect of Si on expression of these genes was lost after three weeks of treatment, indicating these effects are dynamic.

中文翻译：

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硅在减轻烟草铜中毒过程中调节病原体防御相关基因的表达

摘要 用金属处理过的植物可以更好地抵御病原体的感染。这种活性至少部分是由水杨酸 (SA) 信号通路的激活介导的。我们实验室之前的工作表明，硅 (Si) 可以减轻烟草中铜 (Cu) 的毒性压力。然而，在铜胁迫下，Si 如何影响烟草中 SA 生物合成和信号传导相关基因的表达尚不清楚。因此，我们在两个时间点对此进行了调查。用铜毒性处理一周的植物根部表现出异分支酸合成酶 1 的转录水平增加，异分支酸合成酶 1 是一种编码参与 SA 生物合成的关键酶的基因，并且添加 Si 进一步增强了表达。微阵列分析确定了许多疾病防御相关基因在 N 中上调。Cu 毒性处理 1 周后的烟草根，当植物也补充 Si 时进一步增加。然而，Si 对这些基因表达的影响在治疗三周后消失，表明这些影响是动态的。