Yan Huizhuan, Yoo Mi-Jeong, Koh Jin, Liu Lihong, Chen Yazhou, Acikgoz Dogukan, Wang Qiaomei, Chen Sixue
Department of Biology, ‡Interdisciplinary Center for Biotechnology Research, and §Plant Molecular and Cellular Biology, University of Florida , Gainesville, Florida 32611, United States.
J Proteome Res. 2014 Dec 5;13(12):5751-66. doi: 10.1021/pr500739v. Epub 2014 Oct 29.
Jasmonates (JAs) are important phytohormones that regulate a wide range of plant processes including growth, development, senescence, and defense. Jasmonate ZIM-domain (JAZ) proteins are repressors in JA signaling. In Arabidopsis thaliana, 12 JAZ encoding genes were identified, but only a few have been studied in detail. In this study, we focused on characterizing the molecular networks involving JAZ2 and JAZ7. To understand the phenotypes and elucidate the regulatory functions of JAZ2 and JAZ7, shoot and root tissues from wild type (WT), jaz2, and jaz7 were harvested for RNA sequencing and metabolomics. Distinct changes of transcripts and metabolites in JA biosynthesis, primary and specialized metabolism, and oxidative stress were observed among the three genotypes. In particular, many defense or stress-associated metabolites and specialized metabolites were increased in response to methyl jasmonate (MeJA) treatment. Most importantly, these changes were subjected to quantitative modulation by the JAZ proteins at both transcriptional and metabolic levels, the degree of which may control resource allocation between growth and defense. This study not only reveals MeJA-induced molecular reprogramming but also demonstrates the functions of JAZ proteins as key regulators in fine-tuning JA signal transduction.
茉莉酸（JAs）是一类重要的植物激素，可调节包括生长、发育、衰老和防御在内的多种植物生理过程。茉莉酸ZIM结构域（JAZ）蛋白是茉莉酸信号通路中的阻遏蛋白。在拟南芥中，已鉴定出12个编码JAZ的基因，但只有少数得到了详细研究。在本研究中，我们着重于对涉及JAZ2和JAZ7的分子网络进行表征。为了解JAZ2和JAZ7的表型并阐明其调控功能，我们采集了野生型（WT）、jaz2和jaz7的地上部和根部组织用于RNA测序和代谢组学分析。在这三种基因型中，观察到了茉莉酸生物合成、初生代谢和次生代谢以及氧化应激过程中转录本和代谢物的明显变化。特别是，许多与防御或胁迫相关的代谢物以及次生代谢物在茉莉酸甲酯（MeJA）处理后有所增加。最重要的是，这些变化在转录和代谢水平上均受到JAZ蛋白的定量调控，其调控程度可能控制着生长和防御之间的资源分配。本研究不仅揭示了MeJA诱导的分子重编程，还证明了JAZ蛋白作为微调茉莉酸信号转导关键调节因子的功能。
