Phylogeny of Plant CAMTAs and Role of AtCAMTAs in Nonhost Resistance to Xanthomonas oryzae pv. oryzae.
Phylogeny of Plant CAMTAs and Role of AtCAMTAs in Nonhost Resistance to Xanthomonas oryzae pv. oryzae.
复制标题
植物 CAMTA 的系统发育和 AtCAMTA 在非宿主对米黄单胞菌抗性中的作用。
DOI：
10.3389/fpls.2016.00177
复制
发表时间：
2016
影响因子：
5.6
通讯作者：
Cai XZ
中科院分区：
文献类型：
--
作者：
Rahman H;Yang J;Xu YP;Munyampundu JP;Cai XZ
钙调素结合转录激活因子（Calmodulin-bindingtranscription activator，CAMTA）是植物中最重要的钙调转录因子家族之一。然而，CAMTAs的发生、蛋白质相互作用网络以及在植物非寄主抗性中的作用还不清楚。在这项研究中，200 CAMTA基因被确定来自35个物种，代表四个主要的植物谱系。CAMTA基因在多细胞陆地植物中是保守的，但在单细胞真核生物中是不存在的，并且很可能是从两个独立的基因融合中出现的，这两个基因分别编码一个CAMTA样蛋白和一个IQ/CaM结合基序蛋白，分别在胚植物谱系祖先中。大约四分之一的植物CAMTA不包含TIG结构域。这种非TIG类CAMTAs似乎是在与非开花植物分化后，通过有花陆地植物的TIG结构域中的一些关键氨基酸的突变而新进化的。系统发育分析将CAMTA蛋白分为三大类和九个不同的亚类，蛋白质结构域和基序保守性分析的结果支持。大多数（59.0%和21.5%）的CAMTA基因分别含有12或11个内含子。在CAMTA家族的进化过程中，基因复制、内含子侵入、扩增和更新，以及外显子重排和跳跃都明显发生。此外，38个潜在的相互作用的6个拟南芥CAMTA的预测和10个预测的AtCAMTA 3的靶基因表现出变化的Atcamta 3突变体和野生型植物之间的表达。预测的相互作用物主要是转录因子和/或Ca 2 +/CaM调节蛋白，表明AtCAMTA的主要功能机制是对靶基因的转录调控，AtCAMTA可能与其他Ca 2+信号组分共同作用，调节Ca 2+相关的生物学过程。此外，采用Atcamta突变体的功能分析表明，AtCAMTA 3负调节flg 22和非宿主抗黄单胞菌黄单胞菌引起的免疫。可能通过靶向CBP 60 G、EDS 1和NDR 1并涉及SA途径抑制活性氧的积累。
Calmodulin-binding transcription activator (CAMTA) constitutes one of the most important Ca2+/CaM-regulated transcription factor families in plants. Nevertheless, the phylogeny, protein interaction network, and role in nonhost resistance of plant CAMTAs are not well understood. In this study, 200 CAMTA genes were identified from 35 species representing four major plant lineages. The CAMTA genes were conserved in multicellular land plants but absent in unicellular eukaryotes, and were likely to emerge from the fusion of two separate genes encoding a CAMTA-like protein and an IQ/CaM binding motif containing protein, respectively, in the embryophyta lineage ancestor. Approximately one fourth of plant CAMTAs did not contain a TIG domain. This non-TIG class of CAMTAs seems to have newly evolved through mutation of some key amino acids in the TIG domain of flowering land plants after divergence from the non-flowering plants. Phylogenetic analysis classified CAMTA proteins into three major groups and nine distinct subgroups, a result supported by protein domain and motif conservation analyses. Most (59.0 and 21.5%) of the identified CAMTA genes contained 12 or 11 introns, respectively. Gene duplication, intron invasion, enlargement and turnover, as well as exon rearrangements and skipping have apparently occurred during evolution of the CAMTA family. Moreover, 38 potential interactors of six Arabidopsis CAMTAs were predicted and 10 predicted target genes of AtCAMTA3 exhibited changes in expression between Atcamta3 mutants and wild-type plants. The majority of predicted interactors are transcription factors and/or Ca2+/CaM-regulated proteins, suggesting that transcriptional regulation of the target genes might be the dominant functional mechanism of AtCAMTAs, and AtCAMTAs might act together with other Ca2+ signaling components to regulate Ca2+-related biological processes. Furthermore, functional analyses employing Atcamta mutants revealed that AtCAMTA3 negatively regulated the immunity triggered by flg22 and nonhost resistance to Xanthomonas oryzae pv. oryzae via repressing accumulation of reactive oxygen species probably by targeting CBP60G, EDS1, and NDR1 and involving SA pathway.