Double mutants deficient in cytosolic and thylakoid ascorbate peroxidase reveal a complex mode of interaction between reactive oxygen species, plant development, and response to abiotic stresses1[W][OA]
Double mutants deficient in cytosolic and thylakoid ascorbate peroxidase reveal a complex mode of interaction between reactive oxygen species, plant development, and response to abiotic stresses1[W][OA]
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DOI：
10.1104/pp.107.101436
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发表时间：
2007-08-01
期刊：
影响因子：
7.4
通讯作者：
Mittler, Ron
中科院分区：
文献类型：
--
作者：
Miller, Gad;Suzuki, Nobuhiro;Mittler, Ron
活性氧（ROS）在植物中起着关键的信号传导作用，并且在细胞中由在几个不同细胞隔室中发现的复杂的ROS代谢酶网络控制。为了研究如何不同的ROS信号，在不同的细胞隔室中产生的，在细胞中整合，我们产生了一个双突变体缺乏类囊体抗坏血酸过氧化物酶（tylapx）和胞质抗坏血酸过氧化物酶1（apx 1）。我们的分析表明，两种不同的信号产生在植物缺乏胞质APX 1或tylAPX。叶绿体过氧化氢去除酶的缺乏触发细胞中的特定信号，导致对热应激的耐受性增强，而胞质过氧化氢去除酶的缺乏触发不同的信号，导致生长发育不良和对氧化应激的敏感性增强。当这两个信号在细胞中被共激活时（即tylapx/apx 1），检测到一个新的响应，表明这两个不同信号的整合导致了一个新的信号，该信号表现为开花晚，光胁迫期间蛋白质氧化低，以及花青素积累增强。我们的研究结果表明，在拟南芥（拟南芥）的ROS信号的可塑性很高，并建议存在冗余的ROS保护途径，弥补缺乏经典的ROS清除酶，如胞质和叶绿体APXs。进一步研究缺乏tylAPX的植物中增强的耐热性，使用叶绿体到核逆行信号传导缺陷的突变体，表明存在叶绿体产生的胁迫信号，其增强植物的基础耐热性。
Reactive oxygen species (ROS) play a key signaling role in plants and are controlled in cells by a complex network of ROS metabolizing enzymes found in several different cellular compartments. To study how different ROS signals, generated in different cellular compartments, are integrated in cells, we generated a double mutant lacking thylakoid ascorbate peroxidase (tylapx) and cytosolic ascorbate peroxidase1 (apx1). Our analysis suggests that two different signals are generated in plants lacking cytosolic APX1 or tylAPX. The lack of a chloroplastic hydrogen peroxide removal enzyme triggers a specific signal in cells that results in enhanced tolerance to heat stress, whereas the lack of a cytosolic hydrogen peroxide removal enzyme triggers a different signal, which results in stunted growth and enhanced sensitivity to oxidative stress. When the two signals are coactivated in cells (i.e. tylapx/apx1), a new response is detected, suggesting that the integration of the two different signals results in a new signal that manifests in late flowering, low protein oxidation during light stress, and enhanced accumulation of anthocyanins. Our results demonstrate a high degree of plasticity in ROS signaling in Arabidopsis (Arabidopsis thaliana) and suggest the existence of redundant pathways for ROS protection that compensate for the lack of classical ROS removal enzymes such as cytosolic and chloroplastic APXs. Further investigation of the enhanced heat tolerance in plants lacking tylAPX, using mutants deficient in chloroplast-to-nuclei retrograde signaling, suggests the existence of a chloroplast-generated stress signal that enhances basal thermotolerance in plants.