Institute of Technology and Life Sciences, Falenty, Al. Hrabska 3, 05-090 Raszyn, Poland.
Department of Botany, Institute of Biology, Warsaw University of Life Sciences, Nowoursynowska Street 159, 02-776 Warsaw, Poland.
Cells. 2021 Apr 20;10(4):962. doi: 10.3390/cells10040962.
Salicylic acid (SA) is well known hormonal molecule involved in cell death regulation. In response to a broad range of environmental factors (e.g., high light, UV, pathogens attack), plants accumulate SA, which participates in cell death induction and spread in some foliar cells. LESION SIMULATING DISEASE 1 (LSD1) is one of the best-known cell death regulators in . The mutant, lacking functional LSD1 protein, accumulates SA and is conditionally susceptible to many biotic and abiotic stresses. In order to get more insight into the role of LSD1-dependent regulation of SA accumulation during cell death, we crossed the with the mutant, caring mutation in ) gene and having deregulated SA synthesis, and with plants expressing the bacterial gene and thus decomposing SA to catechol. In response to UV A+B irradiation, the mutant exhibited clear cell death phenotype, which was reversed in and / plants. The expression of -genes and the HO content in UV-treated were significantly higher when compared with the wild type. In contrast, and / plants demonstrated comparability with the wild-type level of -genes expression and HO. Our results demonstrate that SA accumulation is crucial for triggering cell death in , while the reduction of excessive SA accumulation may lead to a greater tolerance toward abiotic stress.
水杨酸（SA）是一种众所周知的参与细胞死亡调控的激素分子。植物对广泛的环境因素（如高光、UV、病原体攻击）做出反应时会积累 SA，SA 参与诱导和扩散某些叶片细胞的死亡。LESION SIMULATING DISEASE 1（LSD1）是 中最著名的细胞死亡调节剂之一。突变体缺乏功能性 LSD1 蛋白，会积累 SA，并且对许多生物和非生物胁迫条件具有易感性。为了更深入地了解 LSD1 依赖的 SA 积累在细胞死亡过程中的调节作用，我们将 突变体与 突变体（在 基因中带有突变，导致 SA 合成失调）和表达细菌 基因的植物（能够将 SA 分解为儿茶酚）进行杂交。在 UV A+B 照射下，突变体表现出明显的细胞死亡表型，而在 和 /植物中则得到了逆转。与野生型相比，UV 处理的 中 -基因的表达和 HO 含量显著升高。相比之下，和 /植物的 -基因表达和 HO 水平与野生型相当。我们的结果表明，SA 积累对于触发 中的细胞死亡至关重要，而减少过量的 SA 积累可能会导致对非生物胁迫的耐受性更强。
