N-Hydroxypipecolic acid

N-Hydroxypipecolic acid (N-hydroxypipecolic acid), a plant metabolite, also plays a key role in SAR (systemic acquired resistance) and to a lesser extent in basal resistance.^[1] N-hydroxypipecolic acid requires basal salicylic acid and components of the salicylic acid signaling pathway to induce systemic acquired resistance genes.^[2] N-hydroxypipecolic acid can confer immunity via the salicylic acid receptor NPR1 to reprogram plants at the level of transcription and prime plants for an enhanced defense capacity.^[4]

In vitro experiment it shown that treatment of Arabidopsis Col-0 plants with a 1 mM N-hydroxypipecolic acid solution, either applied via the soil or sprayed on the leaf rosette, triggered a strong SAR response in the leaves.^[3] In addition, when treatment with N-hydroxypipecolic acid in the individual leaves of Col-0 plants, acquired resistance developed not only in the treated leaves but also in distant, systemic leaves.^[5] There is a strong N-hydroxypipecolic acid (1 mM)-mediated priming of the pathogen-triggered accumulation of camalexin. And exogenous N-hydroxypipecolic acid also strongly primed the N-hydroxypipecolic acid-deficient fmo1 mutant for the Psm-triggered accumulation of camalexin. Pretreatment with 1mM N-hydroxypipecolic acid also significantly primed the leaves for an enhanced accumulation of Pip and SA in response to the mock-infiltration, suggesting that N-hydroxypipecolic acid also primes responses to mechanical stress in Arabidopsis.^[6]

References:
[1].Hartmann M, Zeier J. N-hydroxypipecolic acid and salicylic acid: a metabolic duo for systemic acquired resistance. Curr Opin Plant Biol. 2019 Aug;50:44-57.
[2].Nair A, et al. N-hydroxypipecolic acid-induced transcription requires the salicylic acid signaling pathway at basal SA levels. Plant Physiol. 2021 Dec 4;187(4):2803-2819.
[3].Schnake A, et al. Inducible biosynthesis and immune function of the systemic acquired resistance inducer N-hydroxypipecolic acid in monocotyledonous and dicotyledonous plants. J Exp Bot. 2020 Oct 22;71(20):6444-6459.
[4].Zeier J. Metabolic regulation of systemic acquired resistance. Curr Opin Plant Biol. 2021 Aug;62:102050.
[5].Chen YC, et al.?N-hydroxy-pipecolic acid is a mobile metabolite that induces systemic disease resistance in?Arabidopsis. Proc Natl Acad Sci U S A. 2018 May 22;115(21):E4920-E4929.
[6].Yildiz I, et al. The mobile SAR signal N-hydroxypipecolic acid induces NPR1-dependent transcriptional reprogramming and immune priming. Plant Physiol. 2021 Jul 6;186(3):1679-1705.

N-Hydroxypipecolic acid (N-hydroxypipecolic acid) 是一种植物代谢产物，在 SAR（系统获得性抗性）中也起着关键作用，并且在较小程度上在基础抗性中起着关键作用。^[1] N -羟基哌啶酸需要基础水杨酸和水杨酸信号通路的组分来诱导系统获得性抗性基因。^[2] N-羟基哌啶酸可以通过水杨酸受体 NPR1 赋予植物免疫力，从而在转录水平和启动植物以增强防御能力。^[4]

体外实验表明，用 1 mM N-羟基哌啶酸溶液处理拟南芥 Col-0 植物，无论是通过土壤施用还是喷洒在叶莲座上，都会在叶子中引发强烈的 SAR 反应。 ^[3] 此外，当用 N-羟基哌啶酸处理 Col-0 植物的单个叶片时，获得性抗性不仅在处理过的叶片中产生，而且在远处的系统叶片中也产生。^[5] 存在强 N-羟基哌啶酸 (1 mM) 介导的病原体触发的 camalexin 积累的启动。外源性 N-羟基哌啶酸也强烈引发了 N-羟基哌啶酸缺陷型 fmo1 突变体，用于 Psm 触发的 camalexin 积累。用 1mM N-羟基哌啶酸预处理也显着引发叶子以增强 Pip 和 SA 的积累以响应模拟浸润，表明 N-羟基哌啶酸也引发拟南芥对机械应力的反应。^{[6]< /sup>}