Central role of the monothiol-glutaredoxin GrxS17 in shoot apex differentiation upon flowering induction

单硫醇-谷氧还蛋白 GrxS17 在开花诱导后茎尖分化中的核心作用

• 批准号: 251961205
• 负责人: Professorin Dr. Renate Scheibe
• 金额: --
• 依托单位: Lehrstuhl Pflanzenphysiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/251961205?language=en
• 关键词: Central; role; monothiol; glutaredoxin; GrxS17

Plants possess a remarkable amount of redox-active thiol-containing proteins, namely thioredoxins (Trx), glutaredoxins (Grx), peroxiredoxins (Prx) and other redoxins. We focus on a unique member of the Grx family, the monothiol-GrxS17 from Arabidopsis thaliana that consists of a single Trx and three Grx domains. The cytosolic and nuclear-localized protein occurs as a dimer and contains three [2Fe-2S] clusters. The homozygous T-DNA insertion line (SALK_021301.56.00.X) exhibits delayed flowering induction with a complete lack of organ differentiation at the shoot apex resembling the PIN1 phenotype with disturbed auxin distribution. The interaction of GrxS17 with transcription factors and protein kinases found in preliminary work will be studied, both in vivo and in vitro, using various truncated and Cys-mutated forms. The functional importance of these molecular characteristics will be tested in transgenic lines on the knockout background. GrxS17 and its interaction with the transcription factor NF-YC11 and the PKC-like protein kinase will be in the focus of the proposed work. In order to deduce functionally important features, various constructs will be tested in transiently transformed protoplasts and in stably transformed plants. The KO background will be crossed with lines expressing indicators of GSH-redox state (roGFP2) and auxin distribution (DR5 promoter::YFP) in order monitor the induced changes in the living cells. The PIN-like phenotype in GrxS17-KO under long-day regime will be used as a read-out for an impaired differentiation programme and rescue, respectively. The redox- and metal-dependent function of this master regulator of shoot meristem differentiation is part of environmentally adjusted developmental programme. The following questions will be addressed: 1. How does GrxS17 reflect the redox-state of the cytosol/nucleus? Does it function as a metal switch with a [2Fe-2S] cluster that depends on the redox-state of the coordinating Cys residues?2. Which structural characteristics and which domains are essential for its interactions with the transcription factors NF-YC11 and the PCK-like protein kinase? 3. What induces the nuclear transfer and DNA binding of GrxS17 and of its interaction partners? 4. Which signaling pathways are interconnected by GrxS17 acting as a central hub? 5. How is the response to light regime, light quality and quantity, phytohormones and temperature affected in mutant and reconstituted lines of A. thaliana?

植物具有大量氧化还原活性硫醇的蛋白质，即硫氧还蛋白（TRX），谷毒素（GRX），过氧蛋白（PRX）和其他氧化还原蛋白。我们专注于GRX家族的独特成员，即来自拟南芥的单硫醇-grxs17，由单个TRX和三个GRX域组成。胞质和核定位蛋白作为二聚体发生，并包含三个[2FE-2S]簇。纯合T-DNA插入线（SALK_021301.56.00.x）表现出延迟的开花诱导，并且在芽顶完全缺乏类似于PIN1表型的机器人分化，并且具有干扰的生长素分布。将使用各种截短和CYS突变形式研究GRXS17与初步工作中发现的转录因子和蛋白激酶的相互作用。这些分子特征的功能重要性将在基因背景的转基因线中进行测试。 GRXS17及其与转录因子NF-YC11和PKC样蛋白激酶的相互作用将成为拟议的工作的重点。为了推断功能上重要的特征，将在瞬时转化的原生质体和稳定转化的植物中测试各种构建体。 KO背景将与表达GSH-REDOX状态（ROGFP2）和生长素分布（DR5启动子:: YFP）的线条交叉，以监视活细胞的诱导变化。在长期制度下，GRXS17-KO中的PIN样表型将分别用作差异化计划和救援的读出。该芽分生组织分化的主要调节剂的氧化还原和金属依赖性功能是环保发展计划的一部分。将解决以下问题：1。GRXS17如何反映细胞质/核的氧化还原状态？它是否充当具有[2FE-2S]群集的金属开关，取决于协调Cys残基的氧化还原状态？2。 哪些结构特征以及哪些结构域与转录因子NF-YC11和PCK样蛋白激酶的相互作用至关重要？ 3。是什么引起了GRXS17及其相互作用伙伴的核转移和DNA结合？ 4。由GRXS17互连的哪些信号通路充当中央集线器？ 5。在突变体和重建的塔利亚纳线中，对光制，光质量和数量，植物激素和温度的反应如何？