Department of Life Science (BK21 Program), Chung-Ang University , Seoul, South Korea.
Plant Signal Behav. 2020 Dec 1;15(12):1822019. doi: 10.1080/15592324.2020.1822019. Epub 2020 Sep 29.
Mitogen-activated protein kinase kinase kinases (MAPKKKs or MEKKs) are crucial components of the MAPK signaling cascades, which play central roles in the signaling transduction pathways for plant growth, development, and response to abiotic stresses such as drought. The MAPKKK gene families in pepper have not been functionally characterized yet. Here, from the pepper genome, we predicted 27 putative MAPKKK genes belonging to the MEKK subfamily (named ), based on analysis. Phylogenetic analysis revealed that 14 genes were clustered into A5 of the five groups (A1-A5), of which 9 genes are primarily on chromosomes 2 and 7, and are located close to each other. These nine genes showed transcriptional regulation by treatment with abscisic acid (ABA) and drought stress in quantitative reverse-transcription PCR analysis. Among the ABA- and/or drought-induced genes, in a previous study, we isolated ( ABA Induced MAP Kinase 1), which plays a positive role in drought resistance via an ABA-dependent pathway. Our expression analysis and functional characterization of the MEKK subfamily genes will provide a better understanding of the functional roles of pepper MAPK cascades in ABA-mediated drought responses.
丝裂原活化蛋白激酶激酶激酶（MAPKKKs 或 MEKKs）是 MAPK 信号级联反应的关键组成部分，在植物生长、发育以及对干旱等非生物胁迫的响应信号转导途径中发挥着核心作用。辣椒中的 MAPKKK 基因家族尚未进行功能表征。在这里，我们根据 分析，从辣椒基因组中预测了 27 个属于 MEKK 亚家族的假定 MAPKKK 基因（命名为 ）。系统发育分析表明，14 个 基因聚类为 5 个组（A1-A5）的 A5，其中 9 个基因主要位于染色体 2 和 7 上，彼此靠近。通过定量逆转录 PCR 分析，这些 9 个基因显示出对脱落酸（ABA）和干旱胁迫的转录调控。在 ABA 和/或干旱诱导的 基因中，我们之前分离了 （ABA 诱导的 MAP 激酶 1），它通过 ABA 依赖的途径在抗旱性中发挥积极作用。我们对 MEKK 亚家族基因的表达分析和功能表征将有助于更好地理解辣椒 MAPK 级联在 ABA 介导的干旱响应中的功能作用。
