蛋白质组学研究揭示的植物根盐胁迫响应机制

植物根是感知外界盐胁迫信号的首要器官。近年来,人们利用高通量的差异表达蛋白质组学技术,分析了水稻(Oryzasativa)、拟南芥(Arabidopsis thaliana)、大豆(Glycine max)、大麦(Hordeum vulgare)、小麦(Triticum aestivum)、木榄(Bruguieragymnorhiza)和匍匐翦股颖(Agrostis stolonifera)等植物根应答盐胁迫过程中蛋白质组的动态变化特征。通过整合植物根响应盐胁迫蛋白质组学研究结果,揭示了植物根部响应盐胁迫的多种调节机制,包括:利用多种信号通路与蛋白质磷酸化/去磷酸化感知并传递盐胁迫信号;通过膜蛋白与转运蛋白调节离子吸收/外排与区室化;通过抗氧化酶系统活性清除活性氧,并通过合成多种渗透调节物质与防御物质减轻细胞受到的伤害;通过改变参与糖类与能量代谢相关酶的表达调节能量代谢水平;通过细胞骨架动态重塑保持正常的细胞结构、物质运输与信息传递;通过转录、翻译与翻译后调控调节各种蛋白质的动态变化与相互作用;通过调控各种基础代谢与次生代谢水平保持细胞结构与代谢状态正常。     

植物盐胁迫适应性机制研究进展北大核心CSCD

盐胁迫是最重要的非生物胁迫之一,严重威胁植物的生长发育。了解植物盐胁迫适应性机制有利于科学选育耐盐作物,进而有效利用盐地滩涂,减轻日益增加的粮食压力。盐胁迫导致植物体内离子失衡、渗透紊乱以及毒性物质积累,特别是活性氧(ROS,reactive oxygen species)。为了适应盐胁迫,植物需要平衡细胞离子、重塑渗透势并维持ROS稳态。在过去遗传学和生理生化研究揭示了大量的植物盐胁迫响应和调控因子,它们通过多重复杂的胁迫信号通路调控植物的耐盐性。本文综述了近年来盐胁迫下植物的感知、信号转导、基因表达调控、激素调控以及适应性响应,归纳了一套较为完整的植物盐胁迫响应机制。     

叶绿体中活性氧的产生和清除机制

正常情况下植物细胞内活性氧（reactive oxygen species ROS）的产生和清除是平衡的，但是，一旦植物遭受环境胁迫，ROS的积累超过抗氧化剂防护系统清除能力，就会产生氧胁迫损伤细胞。由于叶绿体作为光合作用的场所与其他细胞器相比更易遭受氧化胁迫的伤害。因此，叶绿体进化了更强的防御机制调控电子传递链的氧化还原平衡及叶绿体基质中的氧化还原状态。活性氧具有双重效应．高浓度的活性氧对植物细胞有很强的毒害作用，低浓度时可充当信号分子参与植物的某些防卫反应过程，本文就叶绿体中活性氧的产生（三线态叶绿素、PSI和PSI I电子传递链）、网络清除（抗氧化剂，SOD，As—Glu循环系统，硫氧还蛋白）机制以及功能作用进行了综述。     

蛋白质组学研究揭示的甘蓝型油菜非生物胁迫应答机制

油菜(Brassica napus L.)是我国的主要油料作物之一,在生长发育过程中经常受到干旱、高温、高盐和营养缺乏等非生物胁迫。这些胁迫通常会阻碍油菜的生长发育,导致品质和产量下降。近年来,快速发展的高通量蛋白质组学技术为揭示油菜胁迫响应分子机制提供了新线索。本文综合分析了油菜不同组织/器官(如:叶片、根、下胚轴和种子)在响应盐、高温、干旱、草酸和缺素(磷、硫和硼)等逆境过程中675种蛋白质的丰度变化特征,揭示了其胁迫应答机制,主要包括:(1)通过G蛋白介导的信号通路感知与传递胁迫信号;(2)通过改变参与糖类与能量代谢相关酶的丰度调节代谢水平;(3)通过叶绿素合成的变化调节光合作用;(4)调节转录因子、蛋白质合成与命运相关蛋白质的丰度,从而在转录、翻译以及翻译后修饰等水平上应答逆境;(5)通过调节膜联蛋白、V型H+-ATP酶等质膜蛋白质,促进细胞内物质吸收与转运;(6)通过细胞骨架动态重塑保持正常细胞结构;(7)利用调节抗氧化酶系统清除活性氧,并通过合成多种防御物质减轻细胞受到的伤害。本综述为解析油菜逆境应答网络体系中的关键调控及代谢通路的变化提供了重要信息。     

植物中参与活性氧调控的基因网络

植物体内活性氧（reactive oxygen species,ROS）是氧化还原反应的必然副产物,具极高的活性和毒性,从而对细胞产生毒害。同时,活性氧作为信号分子对很多生理过程诸如植物生长发育、细胞程序化死亡及生物和非生物胁迫应答起调控作用。植物中ROS双重作用的协调机制目前尚不明确,确定的是细胞中ROS维持于稳定水平需要精细的调节。拟南芥中至少包括152个基因组成的网络参与ROS的调控,该网络具高度的灵活性和互补性。本文综述了ROS网络中鉴定的一些关键基因及细胞学定位和协同作用,ROS信号转导,尤其是叶绿体中ROS信号的调控。     

植物活性氧的产生及其作用和危害

活性氧(ROS)是一类由O2转化而来的自由基或具有高反应活性的离子或分子。植物消耗的O2约有1%在叶绿体、线粒体、过氧化物酶体等多种亚细胞单位中被转化成了ROS。ROS有益或有害取决于它在植物体内的浓度。低浓度的ROS作为第二信使能在植物细胞信号转导途径中介导多种应答反应,高浓度的ROS则引起生物大分子的氧化损伤甚至细胞死亡。植物体内ROS产生和清除之间的平衡十分重要,并由一套有效的酶促和非酶促抗氧化系统来监控。该文主要系统介绍了植物ROS的种类、产生部位、在信号转导中的作用及其对植物细胞造成的主要伤害等方面的研究进展,为利用基因工程手段来提高植物对环境胁迫的抗性提供信息和思路。     

植物盐胁迫应答转录因子的研究进展

盐胁迫会导致植物受到初级的渗透胁迫和离子毒害以及次级的氧化胁迫和营养胁迫,严重制约了农业生产.植物盐胁迫应答转录因子能够通过调节下游靶基因的表达减轻盐胁迫对植物造成的伤害.文中基于土壤盐渍化及其对植物的危害、转录因子在植物盐胁迫信号转导网络中的中枢调节作用,综述了盐胁迫应答转录因子参与的盐胁迫信号转导途径、通过形成同源...     

蛋白质可逆磷酸化调节植物细胞离子跨膜运动研究进展

蛋白激酶和蛋白磷酸酶催化的可逆磷酸化是植物细胞中多种信号转导途径中重要的组成因子.本文对蛋白质可逆磷酸化通过调节多种离子跨膜运动而参与植物细胞激发子信号途径、毒性物质诱导的钙离子内流、盐胁迫适应、气孔运动以及蛋白质可逆磷酸化参与胞外与胞内之间Ca2 状况信息传递,调节花粉管顶端Ca2 离子通道活性进行综述,以揭示蛋白质可逆磷酸化在植物细胞离子跨膜运动中的调控作用,为蛋白质可逆磷酸化调节植物生长发育、响应逆境胁迫等机理的研究提供参考.     

利用蛋白质组学技术揭示的植物高温胁迫响应机制

高温是限制植物生长和产量的主要非生物胁迫因子.近年来,蛋白质组学研究为我们从系统生物学水平深入认识植物高温胁迫应答的复杂的分子机制提供了重要信息.目前,已经分析了模式植物拟南芥、主要粮食作物(大豆、水稻和小麦)、耐热植物(匍匐剪股颖、马齿苋、假虎刺),以及野生毛葡萄、胡杨、苜蓿、半夏等应答高温胁迫过程中的蛋白质组变化特征.这些研究共鉴定到838种响应高温胁迫的蛋白质,其中534种蛋白质表达受到高温诱导,304种蛋白质表达受到抑制.本文整合分析了上述植物在应对不同程度高温胁迫(30～45 ℃处理0～10 d)时蛋白质表达模式的变化特征,为解释高温胁迫应答网络体系中重要的信号与代谢通路(如：信号转导、胁迫防御、糖类与能量代谢、光合作用、转录、蛋白质合成与命运、膜与转运等)的变化提供了证据和线索,为深入认识植物应答高温胁迫的分子调控机制奠定了坚实的基础.     

活性氧在植物非生物胁迫响应中功能的研究进展

活性氧(ROS)是植物在响应非生物胁迫过程中不可或缺的组成部分。适量的ROS可通过参与信号转导途径调节植物响应多种胁迫,而过量的ROS致使植物处于氧化应激状态。植物中每个亚细胞室都含有一套独立的ROS产生和清除途径,各自的ROS稳态水平及氧化还原状态也在不断发生变化,表现出各自独特的ROS特征。本文综述了近年来有关ROS在植物非生物胁迫响应过程中功能的研究进展及其在介导快速系统信号转导中的作用,为深入研究ROS在植物非生物胁迫响应中的功能提供参考。     

Comparative proteomic analysis of the Arabidopsis cbl1 mutant in response to salt stress

Many environmental stimuli, including light, biotic and abiotic stress factors, induce changes in cellular Ca(2+) concentrations in plants. Such Ca(2+) signatures are perceived by sensor molecules such as calcineurin B-like (CBL) proteins. AtCBL1, a member of the CBL family which is highly inducible by multiple stress signals, is known to function in the salt stress signal transduction pathway and to positively regulate the plant tolerance to salt. To shed light into the molecular mechanisms of the salt stress response mediated by AtCBL1, a two-dimensional DIGE proteomic approach was applied to identify the differentially expressed proteins in Arabidopsis wild-type and cbl1 null mutant plants in response to salt stress. Seventy-three spots were found altered in expression by least 1.2-fold and 50 proteins were identified by MALDI-TOF/TOF-MS, including some well-known and novel salt-responsive proteins. These proteins function in various processes, such as signal transduction, ROS scavenging, energy production, carbon fixation, metabolism, mRNA processing, protein processing and structural stability. Receptor for activated C kinase 1C (RACK1C, spot 715), a WD40 repeat protein, was up-regulated in the cbl1 null mutant, and two rack1c mutant lines showed decreased tolerance to salt stress, suggesting that RACK1C plays a role in salt stress resistance. In conclusion, our work demonstrated the advantages of the proteomic approach in studies of plant biology and identified candidate proteins in CBL1-mediated salt stress signaling network.     

植物耐盐性机理研究进展

在盐胁迫下环境中某些植物会在发生一些变化。从生理学、生物化学、盐胁迫分子学机制的角度对植物对盐胁迫的反应研究进行了回顾,并提供了一些目前知识水平上能增加植物盐耐性的方法。解释了在盐胁迫下植物的离子吸收、相溶性物质、抗氧化酶、植物激素、光合作用等方面的变化规律,其中也有耐盐植物功能调节的研究,这有助于从多学科研究的角度评估盐胁迫的生态重要性。     

Proteome Dynamics and Physiological Responses to Short-Term Salt Stress in Brassica napus Leaves

Salt stress limits plant growth and crop productivity and is an increasing threat to agriculture worldwide. In this study, proteomic and physiological responses of Brassica napus leaves under salt stress were investigated. Seedlings under salt treatment showed growth inhibition and photosynthesis reduction. A comparative proteomic analysis of seedling leaves exposed to 200 mM NaCl for 24 h, 48 h and 72 h was conducted. Forty-four protein spots were differentially accumulated upon NaCl treatment and 42 of them were identified, including several novel salt-responsive proteins. To determine the functional roles of these proteins in salt adaptation, their dynamic changes in abundance were analyzed. The results suggested that the up-accumulated proteins, which were associated with protein metabolism, damage repair and defense response, might contribute to the alleviation of the deleterious effect of salt stress on chlorophyll biosynthesis, photosynthesis, energy synthesis and respiration in Brassica napus leaves. This study will lead to a better understanding of the molecular basis of salt stress adaptation in Brassica napus and provides a basis for genetic engineering of plants with improved salt tolerance in the future.     

Effects of salinity levels on proteome of Suaeda aegyptiaca leaves

Saline soils are the major problem of cultivated lands of Iran. Suaeda aegyptiaca is a salt-tolerant plant (halophytes) that grow naturally in salt-affected areas of Iran. We have employed proteomics to identify the mechanisms of salt responsiveness in leaves of S. aegyptiaca grown under different salt concentrations. Ten-day-old plants were treated with 0, 150, 300, 450, and 600 mM NaCl. After 30 days of treatment, leaf samples were collected and analyzed using 2-D-PAGE. Out of 700 protein spots reproducible detected within replications, 102 spots showed significant response to salt treatment compared to 0 mM NaCl. We analyzed expression pattern of salt-responsive proteins using a hierarchical and two nonhierarchical (Fuzzy ART and SOM) statistical methods and concluded that Fuzzy ART is the superior method. Forty proteins of 12 different expression groups were analyzed using LC/MS/MS. Of these, 27 protein spots were identified including proteins involved in oxidative stress tolerance, glycinebetain synthesis, cytoskeleton remodeling, photosynthesis, ATP production, protein degradation, cyanide detoxification, and chaperone activities. The expression pattern of these proteins and their possible roles in the adaptation of S. aegyptiaca to salinity is discussed.     

The antioxidant system in Suaeda salsa under salt stress

ABSTRACTSuaeda salsaL. is a typical euhalophyte and is widely distributed throughout the world. Suaeda plants are important halophyte resources, and the physiological and biochemical characteristics of their various organsand their response to salt stress have been intensively studied. Leaf succulence, intracellular ion localization, increased osmotic regulation and enhanced antioxidant capacities are important responses for Suaeda plants to adapt to salt stress. Among these responses, scavenging of reactive oxygen species (ROS) is an important mechanism for plants to withstand oxidative stress and improve salt tolerance. The generation and scavenging pathways of ROS, as well as the expression of scavenging enzymes change under salt stress. This article reviews the antioxidant system constitute of S. salsa, and the mechanisms by which S. salsaantioxidant capacity is improved for salt tolerance. In addition, the differences between types of antioxidant mechanisms in S. salsaare reviewed, thereby revealing the adaptation mechanisms of Suaeda to different habitats. The review provides important clues for the comprehensive understanding of the salt tolerance mechanisms of halophytes.KEYWORDS: Suaeda salsa, halophyte, salt-tolerance mechanism, oxidative stress, antioxidant system     

碱蓬属植物耐盐机理研究进展

碱蓬属(Suaeda)植物是一类典型的真盐生植物,属于重要的盐生植物资源,全球广泛分布.人们已经对20种碱蓬属植物进行了观察和盐胁迫实验,研究了不同器官或组织的生理生化特征及其对盐胁迫的反应,并基于这些研究分析了盐胁迫的应答机制.叶片肉质化、细胞内离子区域化、渗透调节物质增加和抗氧化系统能力增强是碱蓬属植物响应和适应盐胁迫的重要方式和途径.但迄今为止的研究工作尚有一定的局限性,主要包括:研究工作主要集中在植物地上部分,而对植物地下部分的研究较少;多是少数生物学指标或生理学现象的单独观察,而缺乏对生理代谢过程的整体和综合分析;针对某种碱蓬的独立分析较多,而与近缘种的比较研究较少;植物对中性盐胁迫的反应研究较多,而对碱性盐的研究较少.为进一步系统阐明碱蓬属植物的耐盐机制,今后的工作应注重碱蓬属植物响应和适应盐胁迫的信号网络和调控机制研究,基于系统生物学研究思路,采用现代组学技术探索该属植物响应盐胁迫的由复杂信号网络调控的特殊生理特征和特异代谢途径.     

Antioxidative response mechanisms in halophytes: Their role in stress defence

Normal growth and development of plants is greatly dependent on the capacity to overcome environmental stresses. Environmental stress conditions like high salinity, drought, high incident light and low or high temperature cause major crop losses worldwide. A common denominator in all these adverse conditions is the production of reactive oxygen species (ROS) within different cellular compartments of the plant cell. Plants have developed robust mechanisms including enzymatic or nonenzymatic scavenging pathways to counter the deleterious effects of ROS production. There are a number of general reviews on oxidative stress in plants and few on the role of ROS scavengers during stress conditions. Here we review the regulation of antioxidant enzymes during salt stress in halophytes, especially mangroves. We conclude that (i) antioxidant enzymes protect halophytes from deleterious ROS production during salt stress, and (ii) genetic information from mangroves and other halophytes would be helpful in defining the roles of individual isoforms. This information would be critical in using the appropriate genes for oxidative stress defence for genetic engineering of enhanced stress tolerance in crop systems.