Involvement of Histone Modifications in Plant Abiotic Stress Responses

As sessile organisms, plants encounter various environmental stimuli including abiotic stresses during their lifecycle. To survive under adverse conditions, plants have evolved intricate mechanisms to ...     

Ultrastructural Reorganization of Chloroplasts during Plant Adaptation to Abiotic Stress Factors

Russian Journal of Plant Physiology - This review presents a comparative analysis of the literature and the authors’ data on the ultrastructural reorganization of plant chloroplasts adapting...     

生物和非生物胁迫下的植物细胞中丝裂原活化蛋白激酶(MAPK)信号转导

介绍了生物和非生物胁迫下植物细胞中MAPK信号转导的研究进展。     

Molecular Mechanisms of Stress Adaptation in Plant Natural Populations

Recent advances in studies of genetic variation at protein and DNA levels in plant natural populations and its relationship with environmental changes were reviewed with special reference to the works on the wild barley ( Hordeum spontaneum C. Koch.). On one side, adaptation was shown in statistic data, on the other side, the fact that a considerable part of genetic variation does exist within populations (subpopulations) under same ecological condition indicated its maintainability of neutral or near-neutral mutations in natural populations. The researches on adaptive populations of plants, especially on wild soybean ( Glycine soja Sieb. et Zucc.) mainly conducted in author's laboratory, have shown that the most part of molecular variation within and among populations can not be explained by selection particularly as far as the individual uniqueness was concerned. There are some data shown that adaptation may be caused by accumulation of a few near-neutral mutations. Recent publications on molecular mechanisms of morphological evolution has been received special attention to elucidate the discrepancy between molecular evolution and morphological adaptive evolution. A frame on the unified evolution theory has been built. Finally some related viewpoints of philosophy were discussed.     

Glutathione as an Antioxidant and Regulatory Molecule in Plants Under Abiotic Stress Conditions

The glutathione (GSH)/glutathione disulfide (GSSG) redox couple is involved in several physiologic processes in plants under both optimal and stress conditions. It participates in the maintenance of redox homeostasis in the cells. The redox state of the GSH/GSSG couple is defined by its reducing capacity and the half-cell reduction potential, and differs in the various organs, tissues, cells, and compartments, changing during the growth and development of the plants. When characterizing this redox couple, the synthesis, degradation, oxidation, and transport of GSH and its conjugation with the sulfhydryl groups of other compounds should be considered. Under optimal growth conditions, the high GSH/GSSG ratio results in a reducing environment in the cells which maintains the appropriate structure and activity of protein molecules because of the inhibition of the formation of intermolecular disulfide bridges. In response to abiotic stresses, the GSH/GSSG ratio decreases due to the oxidation of GSH during the detoxification of reactive oxygen species (ROS) and changes in its metabolism. The lower GSH/GSSG ratio activates various defense mechanisms through a redox signalling pathway, which includes several oxidants, antioxidants, and stress hormones. In addition, GSH may control gene expression and the activity of proteins through glutathionylation and thiol-disulfide conversion. This review discusses the size and redox state of the GSH pool, including their regulation, their role in redox signalling and defense processes, and the changes caused by abiotic stress.     

SUMO E3连接酶在植物适应非生物胁迫中的作用研究进展

SUMO化(Sumoylation)作为一种广泛存在于真核生物的重要翻译后修饰,在调控植物生长、发育和逆境应答等方面发挥着重要作用。SUMO E3连接酶具有底物识别和选择的作用,直接促进SUMO蛋白与靶蛋白的结合。目前,在植物中已经鉴定出多种SUMO E3连接酶。综述了SUMO E3连接酶在植物适应干旱、盐害、高/低温、营养元素匮缺和重金属毒害等非生物胁迫过程中的作用,并展望了未来植物SUMO化研究的方向,以期为今后植物SUMO化方面的研究提供参考。     

BRs在植物响应非生物胁迫中的作用

油菜素甾体(brassinosteroids,BRs)是植物界普遍存在的一类多羟基化的植物甾体激素,不仅调节植物的生长发育过程,还参与植物对生物和非生物胁迫的响应.概述了BRs的生物合成途径以及信号转导途径,重点阐述了BRs参与非生物胁迫应答的分子机制,展望了BRs未来的研究方向,为深入理解BRs介导的非生物胁迫调控网...     

Accumulation of Natural Growth Inhibiting Substances under Stress Conditions and Its Relation to Adaptation of Plants to Unfavorable Environments

Changes of levels of growth inhibiting substances under drought, salinity, chilling and heat stress in different types of plants were investigated. The presence of ABA in leaf extracts of several plants was identified. Levels of ABA and other inhibitors were increased under stress to different extents, depending on species of the plant and the nature of the stress. The inhibitor contents of two xerophytes, Hedysarum scoparium and Haloxylon ammoderdron, from desert region were also increased by 11.6-fold and 5.2-fold respectively when subjected to water stress, whereas that of mesophyte Robinia pseudoacacia increased 4.5-fold. Correlation between inhibitor level and drought resistance of different wheat cultivars was also noted, The resistant cv. “Hongnong No. 1” accumulated 2–3-fold more inhibitors than the nonresistant cv. “Gansu No.8” when subjected to water or saline stress. The role of growth inhibitors is the adaptation of plants to unfavorable environments was discussed.     

外来入侵植物假臭草的黄酮类成分研究

从外来入侵植物假臭草的70%乙醇提取物的乙酸乙酯萃取物中分离得到5个黄酮化合物,利用波谱方法鉴定为5,6,7,4′-四甲氧基黄酮(1),7-羟基-5,6,4′-三甲氧基黄酮(2),4′-羟基-5,6,7-三甲氧基黄酮(3),5,4′-二羟基-6,7-二甲氧基黄酮(4),5,7,4′-三羟基-6-甲氧基黄酮(5).化合物1～5均首次从该植物中分离得到.     

类受体蛋白激酶与植物非生物胁迫应答

类受体蛋白激酶(receptor-like protein kinase,RLK)是植物信号转导网络中的重要成员,参与介导生长、发育以及逆境胁迫应答等多种细胞代谢过程．在植物细胞中已发现和克隆了富含亮氨酸重复区型(LRR)、凝集素型(lectin-like)和细胞壁相联型(WAK)等不同的RLK亚家族．这些RLK能够感受多种发育和外界环境胁迫信号, 并在植物对非生物胁迫的响应过程中发挥重要的调控作用．本文结合当今国内外研究进展,简述植物RLK的典型结构域特征,详细介绍多种RLK在植物逆境信号识别与转导中发挥的作用,同时对RLK在非生物胁迫应答中的具体作用机制进行了探讨．     

核黄素参与水稻非生物胁迫响应的分析

为探究核黄素在水稻非生物胁迫响应中的作用,以粳稻Kitaake和籼稻T98B为试验材料,考察了核黄素对2种材料的盐、高温、渗透、碱和氧化胁迫响应的影响,重点测定了盐和高温胁迫下水稻体内核黄素合成基因的表达和相关生理指标。结果表明,(1)施加外源核黄素有效提高了2种水稻材料的盐和高温胁迫耐受性,降低了渗透胁迫耐受性,而其氧化和碱胁迫耐受性不受影响。(2)逆境胁迫均不同程度地促进了核黄素在2种水稻材料中的积累,尤其在盐和高温胁迫下促进效果最明显。(3)盐和高温胁迫均诱导了核黄素合成酶基因的表达,促进了核黄素的生物合成,改善了水稻的胁迫耐受性。研究表明,非生物逆境胁迫能促进核黄素在水稻体内的合成和积累,外源核黄素也能明显提高水稻对盐和高温胁迫的耐受性,但却降低了其对渗透胁迫的耐受性。     

Plant Polyamines in Reproductive Activity and Response to Abiotic Stress*

In this review we will focus on two areas in which the accumulated evidence for a critical physiological role of polyamines is becoming compelling, i.e. reproductive activity and response to abiotic stress. Regarding reproductive behavior, it seems clear that polyamines are members of the array of internal compounds required for flower initiation, normal floral organ morphogenesis, fruit growth and fruit ripening in particular plant species. Abiotic stresses such as osmotic stress can “turn on” arginine decarboxylase (ADC) genes, resulting in a rapid increase in their mRNA levels. Localization of ADC enzyme in the chloroplast suggests a role of PAs in the maintenance of photosynthetic activity during senescence responses induced by osmotic stress. We envisage that the use of transgenic plants and improved molecular probes will resolve in the near future the physiological significance of stress-induced changes in PA metabolism as well as the role of these compounds in reproductive activity.     

植物microRNAs在植物发育和非生物胁迫响应中的作用

microRNAs(miRNAs)是一类内源的长度约为22个核苷酸的非编码小分子RNA,其通过对靶基因mRNA进行切割或翻译抑制调节mRNA的表达,在植物中起到重要的作用.主要介绍了植物miRNAs的特征、合成和作用机制,综述了miRNAs在植物生长发育和非生物胁迫响应中的作用.     

NaCl胁迫对西瓜嫁接苗叶片抗氧化酶活性及光合特性的影响

以耐盐性较强的葫芦品种‘超丰抗生王’为砧木,耐盐性较弱的西瓜品种‘秀丽’为接穗,采用营养液水培法,研究了NaCl胁迫对西瓜自根苗和嫁接苗保护酶活性、膜质过氧化及光合特性的影响。结果表明,NaCl胁迫下,嫁接苗和自根苗生物量显著下降,但嫁接苗下降幅度小于自根苗;NaCl胁迫抑制了西瓜自根苗和嫁接苗的气体交换参数,但是嫁接苗的净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)及叶绿素含量显著高于自根苗;NaCl胁迫下西瓜嫁接苗叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均显著高于自根苗,丙二醛含量较自根苗低。上述结果表明,NaCl胁迫下嫁接苗通过维持较高的抗氧化酶活性来提高清除活性氧(ROS)的能力,从而降低氧化损伤,并保持较高光合速率,从而增强西瓜幼苗对盐胁迫的耐性。     

Potato Responds to Salt Stress by Increased Activity of Antioxidant Enzymes

To understand the response of potato to salt stress, antioxidant enzyme activities and ion content were analyzed for a sensitive and a tolerant cultivar. Nodal cuttings of the tolerant cultivar, Kennebec, and the sensitive cultivar, Concord, were exposed to media without or with 30, 60, 90 or 120 mmol/L NaCl for 4 weeks. On exposure to NaCl, the length and fresh and dry weight of both shoots and roots of Concord showed greater decrease than those of Kennebec. The decrease in shoot growth was more severe than that of the root for both cultivars. The K+ content of shoots and roots of both cultivars was reduced in a dose-dependent manner by exposure to NaCl; the Na+ content Increased. Activities of ascorbate peroxidase, catalase and glutathione reductase were increased in NaCl-exposed shoots of Kennebec; the corresponding activities inNaCl-exposed shoots of Concord were decreased. Roots of both cultivars showed similar changes in the activities of these enzymes on exposure to NaCl. These studies established that enzyme activities In Concord shoots are inversely related to the NaCl concentration, whereas those in Kennebec do not show a dose dependency, which is also the case for the roots of both cultivars. Our findings suggest that an Increase in activity of antioxidant enzymes, such as ascorbate peroxidase,cetalase and glutathione reductase, can contribute to salt tolerance in Kennebec, a salt resistant cultivar of potato.     

脯氨酸在植物非生物胁迫耐性形成中的作用

植物作为固着生活的有机体,经常暴露在多变且对其生长发育不利的环境条件中,这些生物或非生物的胁迫因子严重影响着植物的生长、发育、生存和分布。脯氨酸在植物抵抗逆境胁迫过程中起着重要的作用。根据国内外的最新研究进展,结合我们的研究成果,对植物体内脯氨酸的代谢途径、渗透调节、抗氧化、分子伴侣、生长发育信号和毒性等方面进行了综述,并对该研究领域作了展望。     

Potato Responds to Salt Stress by Increased Activity of Antioxidant Enzymes

To understand the response of potato to salt stress, antioxidant enzyme activities and ion content were analyzed for a sensitive and a tolerant cultivar. Nodal cuttings of the tolerant cultivar, Kennebec, and the sensitive cultivar, Concord, were exposed to media without or with 30, 60, 90 or 120 mmol/L NaCI for 4 weeks. On exposure to NaCI, the length and fresh and dry weight of both shoots and roots of Concord showed greater decrease than those of Kennebec. The decrease in shoot growth was more severe than that of the root for both cultivars. The K^＋ content of shoots and roots of both cultivars was reduced in a dose-dependent manner by exposure to NaCl; the Na^＋ content increased. Activities of ascorbate peroxidase, catalase and glutathione reductase were increased in NaCl-exposed shoots of Kennebec; the corresponding activities in NaCI-exposed shoots of Concord were decreased. Roots of both cultivars showed similar changes in the activities of these enzymes on exposure to NaCI. These studies established that enzyme activities in Concord shoots are inversely related to the NaCI concentration, whereas those in Kennebec do not show a dose dependency, which is also the case for the roots of both cultivars. Our findings suggest that an increase in activity of antioxidant enzymes, such as ascorbate peroxidase, catalase and glutathione reductase, can contribute to salt tolerance in Kennebec, a salt resistant cultivar of potato.