拟南芥乙烯信号传递途径

植物激素乙烯早在一百多年前就已经被确认,相关的研究使得乙烯广泛地被应用于农业上.一直到十年前第一个植物激素乙烯受体拟南芥ETR1基因被发现之后,人们对于乙烯信号传递的研究并才真正开始有所突破.以遗传学为基础对乙烯反应突变体所做的分析,使得乙烯信号传递已经成为目前植物信号传递领域中被研究得最清楚的信号传递途径之一.该文着重于回顾乙烯信号传递途径上各个元件的发现和确认,以及如何利用遗传学的方法将现有的突变体相关基因构建出目前广为接受的信号传递的遗传模式.最后,该文就目前所知的乙烯信号传递理论及相关研究,做了总结和深入的讨论.     

配子体自交不亲和信号转导的研究进展

自然界中大多数自交不亲和（self-incompatibility, SI）显花植物表现为配子体SI。配子体SI植物虽然都具有其SI的功能而阻止自我受精,但它们采取的信号转导途径是不同的。目前关于配子体SI信号转导的途径主要有两种：一是茄科、玄参科、蔷薇科中以雌蕊S-RNase为基础的信号转导途径;另一是罂粟科中以花粉管胞质自由钙离子为第二信使的转导途径。文章就配子体SI信号转导的研究进展作一综述。     

植物对盐胁迫响应的信号转导途径

植物通过调控复杂的信号网络来应对盐胁迫。近年来,随着植物基因工程技术的发展,对植物在盐胁迫下信号转导系统的研究取得了一定进展。本文以拟南芥为代表,对盐胁迫下参与调控植物耐盐生理响应的两大类主要信号转导途径——Ca2＋依赖型信号转导通路和丝裂原活化蛋白激酶（MAPK）级联反应途径的研究进展进行综述,主要介绍参与各信号转导通路的组件及诱发的耐盐生理响应等方面,并对该研究领域存在的问题及今后可能的研究方向进行展望。     

Comparative analysis of plant and animal calcium signal transduction element using plant full-length cDNA data

We obtained 32K full-length cDNA sequence data from the rice full-length cDNA project and performed a homology search against NCBI GenBank data. We have also searched homologs of Arabidopsis and other plants' genes with the databases. Comparative analysis of calcium ion transport proteins revealed that the genes specific for muscle and nerve calcium signal transduction systems (VDCC, IP3 receptor, ryanodine receptor) are very different in animals and plants. In contrast, Ca elements with basic functions in cell responses (CNGC, iGlu receptor, Ca(2+)ATPase, Ca2+/Na(+)-K+ ion exchanger) are basically conserved between plants and animals. We also performed comparative analyses of calcium ion binding and/or controlling signal transduction proteins. Many genes specific for muscle and nerve tissue do not exist in plants. However, calcium ion signal transduction genes of basic functions of cell homeostasis and responses were well conserved; plants have developed a calcium ion interacting system that is more direct than in animals. Many species of plants have specifically modified calcium ion binding proteins (CPK, CRK), Ca2+/phospholipid-binding domains, and calcium storage proteins.     

Thylakoid Membrane Protein Kinase Activity as a Signal Transduction Pathway in Chloroplasts

In plants external stimuli are perceived through a cascade of signals and signal transduction pathways. Protein phosphorylation and de-phosphorylation is one of the most important transduction paths for the perception of signals in plants. The highest concentrations of plant phospho-proteins are located in chloroplasts. This facilitates the protection of thylakoid membranes from stress-induced damage and augments adaptive strategies in plants. In this review, the protein kinases associated with phosphorylation of thylakoid membrane protein, and the adaptive changes in thylakoid membrane architecture and developmental cues are given. The presence of membrane bound kinases in thylakoid membranes have evolutionary implications for the signal transduction pathways and the photosynthetic gene expression for thylakoid membrane protein dynamics. This revised version was published online in August 2006 with corrections to the Cover Date.     

植物中丛枝菌根形成的信号途径研究进展

丛枝菌根(arbuscular mycorrhizal, AM)共生是丛枝菌根真菌与大多数陆地植物的根系之间形成的一种互利共生关系。植物给菌根真菌提供碳水化合物; 作为回报, 菌根真菌能够增强植物对矿质营养元素(尤其是磷)的吸收。菌根的形成过程是一系列信号交换和转导的结果, 具有严格并且一致的顺序。本文以植物中菌根形成的信号途径为主线, 对菌根真菌的形成过程和信号转导途径及其方式进行了分析和讨论。高等植物中菌根形成的信号途径与豆科植物的结瘤信号途径部分共享, 并且与钙离子信号途径相关, 但前者更为广泛。尽管该途径中很多过程目前还不十分清楚, 但是相信在不久的将来就可以揭开菌根形成过程中的众多谜团。     

植物中丛枝菌根形成的信号途径研究进展

丛枝菌根(arbuscular mycorrhizal,AM)共生是丛枝菌根真菌与大多数陆地植物的根系之间形成的一种互利共生关系。植物给菌根真菌提供碳水化合物;作为回报,菌根真菌能够增强植物对矿质营养元素(尤其是磷)的吸收。菌根的形成过程是一系列信号交换和转导的结果,具有严格并且一致的顺序。本文以植物中菌根形成的信号途径为主线,对菌根真菌的形成过程和信号转导途径及其方式进行了分析和讨论。高等植物中菌根形成的信号途径与豆科植物的结瘤信号途径部分共享,并且与钙离子信号途径相关,但前者更为广泛。尽管该途径中很多过程目前还不十分清楚,但是相信在不久的将来就可以揭开菌根形成过程中的众多谜团。     

The Rop GTPase: an emerging signaling switch in plants

G proteins are ubiquitous molecular switches in eukaryotic signal transduction, but their roles in plant signal transduction had not been clearly established until recent studies of the plant-specific Rop subfamily of RHO GTPases. Rop participates in signaling to an array of physiological processes including cell polarity establishment, cell growth, morphogenesis, actin dynamics, H₂O₂ generation, hormone responses, and probably many other cellular processes in plants. Evidence suggests that plants have developed unique molecular mechanisms to control this universal molecular switch through novel GTPase-activating proteins and potentially through a predominant class of plant receptor-like serine/threonine kinases. Furthermore, the mechanism by which Rop regulates specific processes may also be distinct from that for other GTPases. These advances have raised the exciting possibility that the elucidation of Rop GTPase signaling may lead to the establishment of a new paradigm for G protein-dependent signal transduction in plants.     

高等植物赤霉素的代谢与信号转导

赤霉素是一种重要的二萜类植物激素,有着广泛而复杂的生物学功能,调节植物整个生命周期不同阶段的生长和发育。本文在分子生物学水平上对高等植物中的赤霉素代谢以及信号转导的最新研究进展进行了总结。     

Genetic bases and functioning of plant signal transduction at virus resistance

Recent insights into virus-host interaction have been compiled in this review, focusing on the genetic basis and the modern conception of the molecular mechanisms of pathogen (mostly viral) recognition by plants. The significance of plant signal transduction systems and their key factors are discussed. The possible role of different elicitors in signal transduction processes has been considered.     

Protein kinases in elicitor signal transduction in plant cells

Plants have the ability to respond to pathogen invasion by specific defense reactions. Components of mammalian signal transduction chains have been identified in plants, and several lines of evidence have implicated such components in elicitor signal transmission in defense responses. In particular, it has been assumed that elicitor signals are transduced via a protein kinase cascade, although the identity of the protein kinases and the function of the phosphorylated proteins remain to be determined. The purpose of this review is to discuss the roles of protein kinases in elicitor signal transduction pathways in plant cells based on recent progress in this field.     

Plant response regulators implicated in signal transduction and circadian rhythm

The so-called 'response regulators' were originally discovered as common components of the widespread histidine (His)-->aspartate (Asp) phosphorelay signal transduction system in prokaryotes. Through the course of evolution, higher plants have also come to employ such prokaryotic response regulators (RRs) for their own signal transduction, such as the elicitation of plant hormone (e.g. cytokinin) responses. Furthermore, plants have evolved their own atypical variants of response regulators, pseudo response regulators (PRRs), which are used to modulate sophisticated biological processes, including circadian rhythms and other light-signal responses. Recent studies using the model plant Arabidopsis thaliana have begun to shed light on the interesting functions of these plant response regulators.     

The evolutionary origin of eukaryotic transmembrane signal transduction

1. A comparison was made of transmembrane signal transduction mechanisms in different eukaryotes and prokaryotes. 2. Much attention was given to eukaryotic microbes and their signal transduction mechanisms, since these organisms are intermediate in complexity between animals, plants and bacteria. 3. Signal transduction mechanisms in eukaryotic microbes, however, do not appear to be intermediate between those in animals, plants and bacteria, but show features characteristic of the higher eukaryotes. 4. These similarities include the regulation of receptor function, adenylate cyclase activity, the presence of a phosphatidylinositol cycle and of GTP-binding regulatory proteins. 5. It is proposed that the signal transduction systems known to operate in present-day eukaryotes evolved in the earliest eukaryotic cells.     

Endomycorrhizal and rhizobial symbiosis: How much do they share?

Abstract

Legume plants enter two important endosymbioses – with soil fungi, forming phosphorus acquiring arbuscular mycorrhiza (AM), and with nitrogen-fixing bacteria, leading to the formation of nitrogen-fixing root nodules. Both symbioses have been studied extensively because these symbioses have great potential for agricultural applications. Although 80% of all living land plants form AM, the nitrogen-fixing root nodule symbiosis with rhizobia is almost exclusively restricted to legumes. Despite varying degree of differences in the morphological responses induced by both endosymbionts in the host plants, significant similarities in the development of both fungal and bacterial symbioses have been reported. The signal perception and signal transduction cascades that initiate nodulation and mycorrhization in legumes partially overlap. Legume genes have been identified that are required for the establishment of both AM and root nodule symbiosis and are referred to as the common SYM genes. Genetic dissection of the common SYM signal transduction pathway required for bacterial and fungal root endosymbiosis has not only unraveled the players involved but also provided a first glimpse at conservation and specialization of signaling cascades essential for nodulation and mycorrhiza development. Based on the observation of common signaling cascades, it is tempting to speculate that the root nodule symbiosis, where fossil records date back to the late Cretaceaous, adopted and subsequently modified more ancient signal transduction pathways leading to AM formation, having already been in place 400 million years ago. This review discusses the common aspects of recognition of mycorrhizal fungi and Rhizobium by the host, and further signal transduction that leads to an effective symbiosis.     

丛枝菌根真菌诱导植物信号物质研究进展

丛枝菌根(AM)真菌侵染植物根系形成菌根共生体过程中能诱导植物合成多种信号物质,如水杨酸(SA)、茉莉酸(JA)、类黄酮、一氧化氮(NO)和过氧化氢(H2O2)等。这些信号分子的传导途径和作用机制备受关注。本文从AM真菌诱导植物信号物质的种类和数量入手,探讨这些信号分子在植物体内的传导途径、生理效应和可能的作用机制,旨在为研究AM真菌与植物之间的共生关系、功能与进化等提供依据。     

植物系统获得的抗病性和信号传导

植物在长期的进化过程中,需要不断地抵抗病原微生物的侵害。在这种长期相互影响的共进化过程中,植物逐渐形成一系列复杂而行之有效的保护机制来抵御病原微生物的侵染。在植物抵御病原微生物侵染的过程中,宿主植物的抗病基因（R）产物与病原微生物无毒基因（Avr）产物的...     

植物抗寒及其基因表达研究进展

植物经过逐渐降低的温度从而提高抗寒能力 ,这个过程被人们称为低温驯化。植物低温驯化过程是一个复杂的生理、生化和能量代谢变化过程 ,这些变化主要包括膜系统的稳定性、可溶性蛋白的积累和小分子渗透物质 ,比如脯氨酸、糖等 ,这些变化中的一些是植物抗寒必需的 ,而另外一些变化不是必需的。主要对冷害和低温生理生化变化、低温诱导表达基因的功能和作用、低温驯化的调节机制及其信号转导方面进行了综述。通过差别筛选 c DNA文库的方法已经鉴定了许多低温诱导表达、进而提高植物抗寒能力的基因 ,其中有脱水素、COR基因和 CBF1转录因子等。低温信号的感受、转导和调节表达是低温驯化的关键环节 ,低温信号的转导过程与干旱胁迫之间具有一定的交叉 ,这为利用 ABA等来提高植物抗寒能力成为可能 ,相信不久的将来人们可以通过提高植物抗寒能力从而增加经济产量成为现实。     

Regulated nuclear targeting

Extracellular signals are transduced to the nucleus through respective signal transduction pathways. Evidence in animals and yeast indicates the importance of regulated nuclear targeting in these processes. Although little is known about plants in this regard, some plant signaling factors have recently been shown to translocate to the nucleus upon receipt of a signal.