Zhang Xiaxiang, Zhuang Lili, Liu Yu, Yang Zhimin, Huang Bingru
College of Agro-grassland Science, Nanjing Agricultural University, 210095, Nanjing, China.
Department of Plant Biology, Rutgers University, New Brunswick, NJ, 08901, USA.
Hortic Res. 2020 Dec 1;7(1):207. doi: 10.1038/s41438-020-00440-8.
Protein phosphorylation is known to play crucial roles in plant tolerance to individual stresses, but how protein phosphorylation is associated with cross-stress tolerance, particularly drought priming-enhanced heat tolerance is largely unknown. The objectives of the present study were to identify phosphorylated proteins and phosphorylation sites that were responsive to drought priming and to determine whether drought priming-enhanced heat tolerance in temperate grass species involves changes in protein phosphorylation. Comparative analysis of phosphoproteomic profiles was performed on leaves of tall fescue (Festuca arundinacea) exposed to heat stress (38/33 °C, day/night) with or without drought priming. A total of 569 differentially regulated phosphoproteins (DRPs) with 1098 phosphorylation sites were identified in response to drought priming or heat stress individually or sequentially. Most DRPs were nuclear-localized and cytosolic proteins. Motif analysis detected [GS], [DSD], and [S..E] as major phosphorylation sites in casein kinase-II and mitogen-activated protein kinases regulated by drought priming and heat stress. Functional annotation and gene ontology analysis demonstrated that DRPs in response to drought priming and in drought-primed plants subsequently exposed to heat stress were mostly enriched in four major biological processes, including RNA splicing, transcription control, stress protection/defense, and stress perception/signaling. These results suggest the involvement of post-translational regulation of the aforementioned biological processes and signaling pathways in drought priming memory and cross-tolerance with heat stress in a temperate grass species.
已知蛋白质磷酸化在植物对单一胁迫的耐受性中发挥关键作用，但蛋白质磷酸化如何与交叉胁迫耐受性相关，特别是干旱引发增强的耐热性，在很大程度上尚不清楚。本研究的目的是鉴定对干旱引发有反应的磷酸化蛋白质和磷酸化位点，并确定温带草种中干旱引发增强的耐热性是否涉及蛋白质磷酸化的变化。对高羊茅（Festuca arundinacea）叶片进行了磷酸化蛋白质组学分析，这些叶片在有或没有干旱引发的情况下暴露于热胁迫（38/33 °C，白天/夜间）。共鉴定出569个差异调节的磷酸化蛋白质（DRP），它们具有1098个磷酸化位点，这些位点分别或依次响应干旱引发或热胁迫。大多数DRP是核定位和胞质蛋白。基序分析检测到[GS]、[DSD]和[S..E]是由干旱引发和热胁迫调节的酪蛋白激酶II和丝裂原活化蛋白激酶中的主要磷酸化位点。功能注释和基因本体分析表明，响应干旱引发以及随后暴露于热胁迫的干旱引发植物中的DRP大多富集在四个主要生物学过程中，包括RNA剪接、转录控制应激保护/防御和应激感知/信号传导。这些结果表明，上述生物学过程和信号通路的翻译后调控参与了温带草种中干旱引发记忆和对热胁迫的交叉耐受性。
