Arabidopsis ECAP Is a New Adaptor Protein that Connects JAZ Repressors with the TPR2 Co-repressor to Suppress Jasmonate-Responsive Anthocyanin Accumulation
Arabidopsis ECAP Is a New Adaptor Protein that Connects JAZ Repressors with the TPR2 Co-repressor to Suppress Jasmonate-Responsive Anthocyanin Accumulation
复制标题
拟南芥 ECAP 是一种新的衔接蛋白，可将 JAZ 阻遏蛋白与 TPR2 辅阻遏蛋白连接起来，抑制茉莉酸响应性花青素积累
DOI：
10.1016/j.molp.2019.10.014
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发表时间：
2020-02-03
期刊：
影响因子：
27.5
通讯作者：
Fu, Ying
中科院分区：
文献类型：
--
作者：
Li, Changjiang;Shi, Lei;Fu, Ying
转录抑制因子介导的抑制机制普遍存在于多种植物激素信号通路中。在拟南芥（Arabidopsis thaliana）中，JASMONATE-ZIM结构域（JAZ）蛋白是转录抑制因子，其作为多种JA反应的负调节因子起作用。JAZ的新型相互作用子（NINJA）是一种连接JAZ和辅助阻遏物TOPLESS（TPL）的衔接蛋白，在JAZ依赖的根生长抑制和防御途径中介导基因阻遏。然而，NINJA或其他衔接蛋白是否用于其他JA响应的生物过程仍有待阐明。在本研究中，我们证明了一个以前未知的蛋白质，ECAP（含ECAP基序的衔接蛋白），直接与JAZ 6和JAZ 8相互作用，并增强其转录抑制活性。我们提供的证据表明，ECAP是一种新的衔接蛋白JAZ 6/8招聘的转录辅阻遏物，TOPLESS相关2（TPR 2），到一个转录阻遏物复合物，抑制WD重复/bHLH/MYB复合物，一个重要的转录激活因子在JA依赖的花青素生物合成途径。我们的研究结果，加上以前的报告，揭示了特定的衔接蛋白在不同的JA反应中发挥关键作用，通过配对不同的JAZ（具有重叠，但也具有特定的功能）与一般的辅阻遏物，TPL和TPR。
Suppression mechanisms mediated by transcriptional repressors commonly exist in diverse phytohormone signaling pathways. In Arabidopsis thaliana, JASMONATE-ZIM DOMAIN (JAZ) proteins are transcriptional repressors that function as negative regulators of diverse JA responses. Novel Interactor of JAZ (NINJA) is an adaptor protein connecting JAZs with the co-repressor, TOPLESS (TPL), to mediate gene repression in JA-dependent root growth inhibition and defense pathways. However, whether NINJA or other adaptor proteins are employed in other JA-responsive biological processes remains to be elucidated. In the present study, we demonstrate that a previously uncharacterized protein, ECAP (EAR motif-Containing Adaptor Protein), directly interacts with JAZ6 and JAZ8 and enhances their transcriptional repression activities. We provide evidence that ECAP is a novel adaptor protein for JAZ6/8 recruitment of the transcriptional co-repressor, TOPLESS-RELATED 2 (TPR2), into a transcriptional repressor complex that represses the WD-repeat/bHLH/MYB complex, an important transcriptional activator in the JA-dependent anthocyanin biosynthesis pathway. Our findings, together with previous reports, reveal that specific adaptor proteins play a critical role in distinct JA responses by pairing different JAZs (which possess overlapping but also specific functions) with the general co-repressors, TPL and TPRs.