植物细胞一氧化氮信号转导研究进展

一氧化氮(nitric oxide, NO)作为重要的信号分子, 调控植物的种子萌发、根形态建成和花器官发生等许多生长发育过程, 并参与气孔运动的调节以及植物对多种非生物胁迫和病原体侵染的应答过程。已经知道, 精氨酸依赖的NOS途径和亚硝酸盐依赖的NR途径是植物细胞NO产生的主要酶促合成途径。NO及其衍生物能够直接修饰底物蛋白的金属基团、半胱氨酸和酪氨酸残基, 通过金属亚硝基化、巯基亚硝基化和Tyr-硝基化等化学修饰方式, 调节靶蛋白的活性, 并影响cGMP和Ca²⁺信使系统等下游信号途径, 调控相应的生理过程。最新的一些研究结果也显示, MAPK级联系统与NO信号转导途径之间存在复杂的交叉调控。此外, 作为活跃的小分子信号, NO和活性氧相互依赖并相互影响, 共同介导了植物的胁迫应答和激素响应过程。文章综述了植物NO信号转导研究领域中一些新的研究进展, 对NO与活性氧信号途径间的交叉作用等也作了简要介绍。     

植物一氧化氮信号分子的研究进展

一氧化氮(NO)作为一种重要的信号分子,不仅参与植物的种子休眠和萌发以及根的形态建成等生长发育过程,还参与调节植物细胞的气孔运动以及植物抗逆应答反应。该文结合最新研究成果,总结了植物NO信号调控机理的研究进展,主要包括NO合成途径、信号转导途径及其与其它信号分子之间的交叉反应和对植物抗逆的调控作用等。     

一氧化氮调控植物缺铁响应的研究进展

一氧化氮(nitric oxide,NO)是植物体内一种重要的信号分子,不仅对植物的生长发育具有重要的调控作用,而且在植物应答缺铁胁迫中同样扮演着关键角色。近年来,有关NO介导的植物缺铁响应调控机制研究取得了一系列重要进展。本文重点针对植物体内NO的合成及其信号转导途径在缺铁胁迫应答中的作用和NO与其他信号分子互作介导植物缺铁响应调控研究进行系统综述与展望,以加深NO在植物缺铁响应调控功能的认识。     

一氧化氮对植物重金属胁迫抗性的影响研究进展

一氧化氮(NO)作为一种重要的信号分子,在调节植物重金属胁迫抗性方面上起着非常重要的作用。综述了NO在植物体内的产生途径,重金属胁迫下植物体内内源NO含量的变化以及外源NO与内源NO对植物重金属胁迫抗性的影响。大量研究表明外源NO能够增强植物对重金属胁迫的抗性,一方面是通过增强植物细胞的抗氧化系统或直接清除活性氧,另一方面是通过影响植物对重金属的吸收以及重金属在植物细胞内的分布。然而内源NO在调节植物重金属胁迫抗性上的功能角色仍存在争议。有些研究表明内源NO是有益的,能够缓解重金属胁迫诱导的毒性;但是也有证据表明内源NO是有害的,能够通过促进植物对重金属的吸收以及对植物螯合素进行S-亚硝基化弱化其解毒功能,从而参与重金属诱导的毒害反应和细胞凋亡过程。     

AP2/ERF转录因子调控植物非生物胁迫响应研究进展

低温、干旱、高盐和缺氧等多种不良环境影响植物的生长发育, 植物通过长期进化形成复杂的调节机制来适应这些不利条件。AP2/ERF是植物特有的转录因子, 在各种胁迫响应过程中发挥关键调控作用。近年来, 越来越多的研究表明, 植物激素介导的信号级联通路与逆境胁迫响应关系密切, AP2/ERF转录因子可与激素信号转导协同形成交叉调控网络。许多AP2/ERF转录因子通过响应植物激素脱落酸和乙烯, 激活依赖或不依赖于脱落酸和乙烯的胁迫响应基因的表达。此外, AP2/ERF转录因子参与赤霉素、细胞分裂素和油菜素内酯介导的生长发育和胁迫应答。该文简要综述了AP2/ERF转录因子的结构特征、转录调控、翻译后修饰、结合位点、协同互作蛋白及其参与调控依赖或不依赖激素信号转导途径的非生物胁迫响应研究进展, 为解析不同AP2/ERF转录因子在调控激素和胁迫响应网络中的作用提供理论依据。     

AP2/ERF转录因子调控植物非生物胁迫响应研究进展

低温、干旱、高盐和缺氧等多种不良环境影响植物的生长发育,植物通过长期进化形成复杂的调节机制来适应这些不利条件。AP2/ERF是植物特有的转录因子,在各种胁迫响应过程中发挥关键调控作用。近年来,越来越多的研究表明,植物激素介导的信号级联通路与逆境胁迫响应关系密切,AP2/ERF转录因子可与激素信号转导协同形成交叉调控网络。许多AP2/ERF转录因子通过响应植物激素脱落酸和乙烯,激活依赖或不依赖于脱落酸和乙烯的胁迫响应基因的表达。此外,AP2/ERF转录因子参与赤霉素、细胞分裂素和油菜素内酯介导的生长发育和胁迫应答。该文简要综述了AP2/ERF转录因子的结构特征、转录调控、翻译后修饰、结合位点、协同互作蛋白及其参与调控依赖或不依赖激素信号转导途径的非生物胁迫响应研究进展,为解析不同AP2/ERF转录因子在调控激素和胁迫响应网络中的作用提供理论依据。     

植物亚硝基谷胱甘肽还原酶在胁迫反应中的作用研究

信号分子一氧化氮(Nitric oxide,NO)参与植物的许多生理反应过程,例如:萌发、气孔的关闭、侧根的发育以及生物与非生物的胁迫反应过程等,主要的调控形式是与半胱氨酸上的硫基发生可逆的S-亚硝基化作用。NO的半衰期很短,这限制了它在细胞中的生理功能,与胞内含硫基的分子形成的S-亚硝基硫醇(S-nitrosothiols,SNOs)的化学性质稳定,在植物的生长发育及抗逆过程中SNOs参与NO的运输、扩散、储存以及蛋白的翻译后修饰过程。谷胱甘肽(Glutathione,GSH)与NO发生S-亚硝基化作用形成S-亚硝基谷胱甘肽(S-nitrosoglutathione,GSNO),GSNO作为NO的储存与转运形式,可以把NO转到靶蛋白上,使靶蛋白发生亚硝基化。亚硝基谷胱甘肽还原酶(S-Nitrosoglutathione reductase,GSNOR)是生物体中的一类保守蛋白,通过还原亚硝基谷胱甘肽从而调节细胞内NO及亚硝基硫醇(S-nitrosothiols,SNOs)水平,保护机体免受亚硝化的胁迫,间接的调控的细胞的氧化状态。GSNO是一个天然的NO储存库,GSNOR是调节机体亚硝基化水平的关键基因。主要对GSNOR参与的植物生长发育、生物与非生物胁迫等过程进行了概述,探讨GSNOR在植物生长发育及胁迫反应中的作用机制,将有助于我们对NO生理功能的了解,旨在为将来GSNOR的研究提供理论参考和思路。     

植物免疫应答过程中 Ca2 ＋及 CaM/CML 的功能

钙离子是一个多功能的第二信使,在植物响应各种生理刺激时,Ca2＋参与调节植物的多种生长发育和胁迫适应过程。在这些过程中,Ca2＋信号带有特异性标签,通过Ca2＋结合蛋白及其下游靶蛋白感知不同刺激并翻译成响应的细胞反应。钙调素（CaM）和钙调素类蛋白（CML）是Ca2＋主要感受器,通过调节不同靶蛋白的活性调控多种细胞功能。最近在植物对抗病原菌的防卫反应中有关Ca2＋／CaM信号转导系统的研究取得了一定进展。重点关注植物免疫应答过程中受CaM／CML调控的信号组分的研究,包括参与Ca2＋信号产生和Ca2＋依赖的表达基因组分调控。     

NO在植物中的调控作用

一氧化氮（NO）是一种易扩散的生物活性分子,是生物体内重要的信号分子。植物细胞通过NO合酶、硝酸还原酶、或非生化反应途径产生NO。NO参与植物生长发育调控和对生物与非生物环境胁迫的应答反应,大量证据表明NO是植物防御反应中的关键信使,其信号转导机制也受到越来越多的关注。本文主要通过讨论NO的产生、对植物生长周期的影响、在植物代谢中的信号调节以及参与细胞凋亡来阐述NO在植物中的作用。     

NO在植物中的调控作用

一氧化氮(NO)是一种易扩散的生物活性分子,是生物体内重要的信号分子.植物细胞通过NO合酶、硝酸还原酶、或非生化反应途径产生NO.NO参与植物生长发育调控和对生物与非生物环境胁迫的应答反应,大量证据表明NO是植物防御反应中的关键信使,其信号转导机制也受到越来越多的关注.本文主要通过讨论NO的产生、对植物生长周期的影响、在植物代谢中的信号调节以及参与细胞凋亡来阐述NO在植物中的作用.     

The diversity of nitric oxide function in plant responses to metal stress

Nitric oxide (NO) emerges as signalling molecule, which is involved in diverse physiological processes in plants. High mobility metal interferes with NO signaling. The exogenous NO alleviates metal stress, whereas endogenous NO contributes to metal toxicity in plants. Owing to different cellular localization and concentration, NO may act as multifunctional regulator in plant responses to metal stress. It not only plays a crucial role in the regulation of gene expression, but serves as a long-distance signal. Through tight modulation of redox signaling, the integration among NO, reactive oxygen species and stress-related hormones in plants determines whether plants stimulate death pathway or activate survival signaling.     

活性氧中间体和NO在植物抗病中的作用

植物与病原菌互作时,活性氧中间体（reactive oxygen intermediates,ROI）和一氧化氮(NO)参与了植物抗病性的建立。寄主与病原菌非亲合性互作产生二次氧爆发高峰,体内NO增加。许多氧化酶可以催化氧爆发产生ROI。ROI和NO通过氧化还原信号启动寄主细胞局部的过敏性坏死反应和全株系统获得性抗病性。     

Phospholipase D in the signaling networks of plant response to abscisic acid and reactive oxygen species

Phospholipase D (PLD) has been implicated in different cellular processes in plant growth, development, and stress responses. Recent results have provided insights into the molecular mechanism by which PLD and its lipid product phosphatidic acid (PA) participate in cell signaling. Effector proteins that have been identified for PLD and PA in plants include a heterotrimeric G protein, protein phosphatase, and protein kinase. Evidence has been presented for a direct link from a PLD, PA, to a target protein in specific physiological processes. PLD and PA play multiple roles in the signaling networks of plant response to abscisic acid and reactive oxygen species.     

Nitric Oxide Signaling in Plant Responses to Abiotic Stresses

Nitric oxide (NO) plays important roles in diverse physiological processes In plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.     

Nitric Oxide Signaling in Plant Responses to Abiotic Stresses

Nitric oxide (NO) plays important roles in diverse physiological processes In plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.     

Nitric oxide is critical for inducing phosphatidic acid accumulation in xylanase-elicited tomato cells

Nitric Oxide (NO) is a second messenger related to development and (a)biotic stress responses in plants. We have studied the role of NO in signaling during plant defense responses upon xylanase elicitation. Treatment of tomato cell cultures with the fungal elicitor xylanase resulted in a rapid and dose-dependent NO accumulation. We have demonstrated that NO is required for the production of the lipid second messenger phosphatidic acid (PA) via the activation of the phospholipase C (PLC) and diacylglycerol kinase (DGK) pathway. Defense-related responses downstream of PA were studied. PA and, correspondingly, xylanase were shown to induce reactive oxygen species production. Scavenging of NO or inhibition of either the PLC or the DGK enzyme diminished xylanase-induced reactive oxygen species production. Xylanase-induced PLDbeta1 and PR1 mRNA levels decreased when NO or PA production were compromised. Finally, we have shown that NO and PA are involved in the induction of cell death by xylanase. Treatment with NO scavenger cPTIO, PLC inhibitor U73122, or DGK inhibitor R59022 diminished xylanase-induced cell death. On the basis of biochemical and pharmacological experimental results, we have shown that PLC/DGK-derived PA represents a novel downstream component of NO signaling cascade during plant defense.     

Protein S‐Nitrosylation in plants: Current progresses and challenges

Nitric oxide(NO) is an important signaling molecule regulating diverse biological processes in all living organisms. A major physiological function of NO is executed via protein S-nitrosylation, a redox-based the past decade, significant progress has been made in functional characterization of S-nitrosylated proteins Inviteposttranslational modification by covalently adding a NO molecule to a reactive cysteine thiol of a target protein.S-nitrosylation is an evolutionarily conserved mechanism modulating multiple aspects of cellular signaling. Duringin plants. Emerging evidence indicates that protein Snitrosylation is ubiquitously involved in the regulation of plant development and stress responses. Here we review current understanding on the regulatory mechanisms of protein S-nitrosylation in various biological processes in plants and highlight key challenges in this field.     

MAPK级联途径参与ABA信号转导调节的植物生长发育过程

植物激素ABA参与调控植物生长发育和生理代谢以及多种胁迫应答过程,促分裂原活化蛋白激酶（MAPK）级联途径应答于多种生物和非生物胁迫,广泛参与调控植物的生长发育。MAPK级联途径与ABA信号转导协同作用参与调控植物种子萌发、气孔运动和生长发育,本文主要归纳了植物中受ABA调控激活的MAPK级联途径成员,阐述了它们参与ABA信号转导调控植物生理反应和生长发育的过程,并对MAPK级联途径与ABA信号转导的研究方向作出了展望,指出对MAPK下游底物的筛选是完善MAPK级联途径的重要组成部分。     

CDPK-mediated abiotic stress signaling

Calcium-dependent protein kinases (CDPKs) constitute a large multigene family in various plant species. CDPKs have been shown to have important roles in various physiological processes, including plant growth and development and abiotic and biotic stress responses in plants. Functional analysis using gain-of-function and loss-of-function mutants has revealed the biological function of CDPKs in planta. Several CDPKs have been shown to be essential factors in abiotic stress tolerance, positively or negatively regulating stress tolerance by modulating ABA signaling and reducing the accumulation of reactive oxygen species (ROS). This review summarizes recent results describing the biological function of CDPKs that are involved in abiotic stress tolerance.