State Key Laboratory of Conservation and Utilization of Subtropical Agro- Bioresources, Guangdong Laboratory for Lingnan Modern Agriculture, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, China.
State Key Laboratory of Conservation and Utilization of Subtropical Agro- Bioresources, Guangdong Laboratory for Lingnan Modern Agriculture, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, 510642, China.
Plant Physiol Biochem. 2024 Nov;216:109099. doi: 10.1016/j.plaphy.2024.109099. Epub 2024 Sep 7.
Lipids and Ca are involved as intermediate messengers in temperature-sensing signaling pathways. Arbuscular mycorrhizal (AM) symbiosis is a mutualistic symbiosis between fungi and terrestrial plants that helps host plants cope with adverse environmental conditions. Nonetheless, the regulatory mechanisms of lipid- and Ca-mediated signaling pathways in mycorrhizal plants under cold and heat stress have not been determined. The present work focused on investigating the lipid- and Ca-mediated signaling pathways in arbuscular mycorrhizal (AM) and non-mycorrhizal (NM) roots under temperature stress and determining the role of Ca levels in AM symbiosis and temperature stress tolerance in perennial ryegrass (Lolium perenne L.) Compared with NM plants, AM symbiosis increased phosphatidic acid (PA) and Ca signaling in the roots of perennial ryegrass, increasing the expression of genes associated with low temperature (LT) stress, including LpICE1, LpCBF3, LpCOR27, LpCOR47, LpIRI, and LpAFP, and high temperature (HT) stress, including LpHSFC1b, LpHSFC2b, LpsHSP17.8, LpHSP22, LpHSP70, and LpHSP90, under LT and HT conditions. These effects result in modulated antioxidant enzyme activities, reduced lipid peroxidation, and suppressed growth inhibition caused by LT and HT stresses. Furthermore, exogenous Ca application enhanced AM symbiosis, leading to the upregulation of Ca signaling pathway genes in roots and ultimately promoting the growth of perennial ryegrass under LT and HT stresses. These findings shed light on lipid and Ca signal transduction in AM-associated plants under LT and HT stresses, emphasizing that Ca enhances cold and heat tolerance in mycorrhizal plants.
脂质和 Ca 作为中间信使参与温度感应信号通路。丛枝菌根（AM）共生是真菌与陆生植物之间的互利共生关系，有助于宿主植物应对不利的环境条件。然而，在冷、热胁迫下，脂类和 Ca 介导的信号通路在菌根植物中的调控机制尚不清楚。本研究主要研究了温度胁迫下丛枝菌根（AM）和非菌根（NM）根中的脂类和 Ca 介导的信号通路，并确定 Ca 水平在 AM 共生和多年生黑麦草（Lolium perenne L.）对温度胁迫耐受性中的作用。与 NM 植物相比，AM 共生增加了多年生黑麦草根中的磷脂酸（PA）和 Ca 信号，增加了与低温（LT）胁迫相关的基因的表达，包括 LpICE1、LpCBF3、LpCOR27、LpCOR47、LpIRI 和 LpAFP，以及高温（HT）胁迫相关的基因的表达，包括 LpHSFC1b、LpHSFC2b、LpsHSP17.8、LpHSP22、LpHSP70 和 LpHSP90，在 LT 和 HT 条件下。这些作用导致抗氧化酶活性的调节、脂质过氧化的减少以及 LT 和 HT 胁迫引起的生长抑制的抑制。此外，外源 Ca 处理增强了 AM 共生，导致根系 Ca 信号通路基因的上调，最终促进了 LT 和 HT 胁迫下多年生黑麦草的生长。这些发现揭示了 LT 和 HT 胁迫下 AM 相关植物中脂类和 Ca 信号转导的机制，强调了 Ca 增强了菌根植物的耐寒性和耐热性。
