Hirakawa Takeshi, Tanno Seia, Ohara Kazuaki
Kirin Central Research Institute, Kirin Holdings Company, Ltd., 26-1, Muraoka-Higashi 2, Fujisawa, Kanagawa 251-8555, Japan.
Plant Biotechnol (Tokyo). 2024 Mar 25;41(1):71-76. doi: 10.5511/plantbiotechnology.23.1211a.
Heat stress, which occurs when temperatures exceed the optimal range for growth, challenges the maintenance of crop yield because it disrupts plant homeostasis at the cellular and developmental levels. Chemical priming, which can activate the response to environmental stress using chemical compounds, is a promising method of maintaining plant growth under stressful conditions. Recently, we found that the non-proteogenic amino acid N-acetylglutamic acid (NAG) confers tolerance to oxidative stress through the activation of genes related to scavenging reactive oxygen species in plants. However, it has been unknown whether NAG alleviates environmental stress except oxidative stress. Here, we revealed that the response to heat stress was enhanced by exogenous treatment with NAG in plants. NAG alleviated the reduction in chlorophyll content induced by heat stress in . Gene expression analysis showed that NAG activates the transcription factor , which is regarded as a master regulator of the transcriptional cascade in response to heat stress. NAG induces histone H4 acetylation, an active histone modification, at the locus, suggesting that NAG could activate the expression of based on epigenetic modifications such as histone acetylation. Additionally, we found that treated with NAG showed tolerance to heat stress. These results suggest that NAG could be used for chemical priming in the maintenance of plant growth under heat-stress conditions.
当温度超过生长的最佳范围时会发生热应激，这对作物产量的维持构成挑战，因为它会在细胞和发育水平上破坏植物的体内平衡。化学引发是一种利用化合物激活对环境胁迫的反应的方法，是在胁迫条件下维持植物生长的一种有前景的方法。最近，我们发现非蛋白质氨基酸N-乙酰谷氨酸（NAG）通过激活植物中与清除活性氧相关的基因来赋予对氧化应激的耐受性。然而，除了氧化应激外，NAG是否能缓解环境胁迫尚不清楚。在这里，我们揭示了在植物中用NAG进行外源处理可增强对热应激的反应。NAG减轻了热应激诱导的叶绿素含量的降低。基因表达分析表明，NAG激活了转录因子，该转录因子被认为是热应激反应中转录级联的主要调节因子。NAG在基因座处诱导组蛋白H4乙酰化，这是一种活跃的组蛋白修饰，表明NAG可以基于组蛋白乙酰化等表观遗传修饰激活基因的表达。此外，我们发现用NAG处理的植物对热应激表现出耐受性。这些结果表明，NAG可用于在热应激条件下维持植物生长的化学引发。
