The excitability of plant cells: With a special emphasis on characean internodal cells

This review describes the basic principles of electrophysiology using the generation of an action potential in characean internodal cells as a pedagogical tool. Electrophysiology has proven to be a powerful tool in understanding animal physiology and development, yet it has been virtually neglected in the study of plant physiology and development. This review is, in essence, a written account of my personal journey over the past five years to understand the basic principles of electrophysiology so that I can apply them to the study of plant physiology and development. My formal background is in classical botany and cell biology. I have learned electrophysiology by reading many books on physics written for the lay person and by talking informally with many patient biophysicists. I have written this review for the botanist who is unfamiliar with the basics of membrane biology but would like to know that she or he can become familiar with the latest information without much effort. I also wrote it for the neurophysiologist who is proficient in membrane biology but knows little about plant biology (but may want to teach one lecture on “plant action potentials”). And lastly, I wrote this for people interested in the history of science and how the studies of electrical and chemical communication in physiology and development progressed in the botanical and zoological disciplines.     

植物转基因技术的诞生和发展

在过去的几十年里,转基因技术经历了从诞生、成长到大规模商业化应用等阶段,在农业生产中表现出巨大优势和潜力。本文简单介绍转基因技术的诞生、发展历程以及产业化情况。     

Plant tissue culture. Biotechnology. Milestones

Summary The progress in the development of the technologies of plant tissue and cell culture over the past four decades has been remarkable. This article covers my personal reflections on the various topics and is based on my involvement in the field during that period. There are three fundamental technologies which constitute most of what is referred to as plant in vitro technologies or tissue culture. The origin and some of the key persons involved in the development of each of these procedures will be discussed. The technology that is most common is growing plant tissue on gel-solidified nutrient media. That technology is being used in the most vital procedures, namely the regeneration of plants from cultured cells. The culture of plant cells in liquid suspension was developed very shortly after that, and has become a very effective technology for plant regeneration by somatic embryogenesis. The method of meristem culture arose out of a need for developing plants that were virus-free. In many species the technique is now being used to produce virus-free crop plants. Another important technology is the culture of anthers and microspores for producing haploid and homozygous plants. Included with plant tissue culture is the development of the plant protoplast and cell fusion technologies for the production of new plant hybrids. The final aspect of the development concerns the integration of tissue culture with molecular genetics, which has developed into the rapidly expanding field of biotechnology.     

Food for thought from plant and animal genomes

A report on the Plant and Animal Genome XXI meeting, held in San Diego, USA, January 12-16, 2013.

Meeting Report

On 12 January, on a morning full of blue sky and cold sunshine, the Plant and Animal Genome XXI meeting opened its doors for the 21st time at the Town and Country Hotel in San Diego. I arrived a couple of hours late, a newbie toting a roller suitcase, a little unprepared for the sheer scope of the meeting I was about to attend. The diversity of topics and attendees at the meeting, ''The Largest Ag-Genomics Meeting in the World'', was stunning. Within my first hour, I would wind up eating my boxed lunch with a member of the transitional government of Egypt, who moonlights as a grad student in Colorado; and within my first afternoon, I would hear talks about drought resistance in rice, marker-assisted breeding in sweet cherry and transgressive segregation in cotton, not to mention the 12 concurrent sessions on topics from citrus genomes to swine breeding. As a plant developmental biologist interested in international agriculture, I chose talks with an eye towards the border between basic and applied research, the brackish zone where molecular biological innovations find their way into research centers, field trials, and ultimately, farmers'' fields. In this report, I will present examples of the diverse and exciting work being done at this intersection, and will conclude by highlighting some emerging trends and challenges on the horizon.     

植物microRNA的生物合成和调控功能

植物microRNA(miRNA)是一类21～24个核苷酸长度的小RNA分子。它的生物合成机制及其对植物生长发育的重要调控作用是人们普遍关注的科学问题和深入探索的研究对象。目前,RNA分子生物学在理论和技术上日趋完善,正在成为一门独立的新兴学科,对生物相关学科的发展产生了重要影响。其中,植物miRNA的生物合成和调控功能是植物小RNA分子生物学的核心问题之一。该文提供植物miRNA领域的最新研究成果,在此基础上对未来的学科发展提出新的建议。     

Chemical biology approaches in plant stress research

In addition to their importance as essential agrochemicals and life-saving drugs, small molecules serve as powerful research tools to address questions at all levels of biological complexity from protein function to plant biotic interactions. In certain contexts, chemical tools are complementary or even preferred to genetic analysis, since not all experimental systems are amenable for genetic dissection. For example, mutants impaired in oxygen sensing cannot easily be recovered. Pharmacological and chemical genetics approaches have come to the rescue of biologists in unraveling such genetically intractable systems. In this review, I have discussed my own efforts to analyze oxygen deprivation signaling in plants to illustrate the validity of small molecular approaches in elucidating an essential pathway such as oxygen sensing. Chemical biology is also a potent approach to tease out genetically redundant biological processes. The recent breakthrough in identifying the elusive abscisic acid receptors has clearly demonstrated the power of chemical tools in dissecting redundant pathways and led to the blossoming of this area as a distinct discipline of plant biology research. I present a summary of this work and conclude the review with potential challenges in using chemical tools.     

基于高通量测序的植物群体基因组学研究进展

作为群体遗传学一种新的表现形式,群体基因组学是将基因组概念和技术与群体遗传学理论体系相结合,通过覆盖全基因组范围内的多态位点的分布式样推测位点特异性效应和全基因组效应,从而提升人们对微进化的理解。近年来,随着第二代高通量测序技术的出现和改进,完成基因组测序的植物种类迅速增加,大规模的重测序也随之开展。与此同时,在一些尚未完成基因组测序的植物物种中,也开展了一些平行测序。这些重测序和平行测序极大地促进了群体基因组学的发展,加深了人们对相关植物种群在基因组水平上的遗传多样性、连锁不平衡水平、选择作用、群体历史及复杂性状的分子机理等群体基因组学方面的认识。本文简要介绍了群体基因组学的概念、研究方法等,重点综述了基于高通量测序的植物群体基因组学的研究动态,展望了植物群体基因组学的发展前景并讨论了存在的问题,以期为相关研究提供借鉴和参考。     

植物抗病相关基因分离策略

近年来植物基因克隆技术已经取得了很大进展。文章对分离植物抗病相关基因的一系列策略及其研究进展进行了综述,并对这些技术的异同,各自的优缺点,以及它们在植物中的应用现状及前景作了评述。     

植物抗病的分子生物学基础

随着分子生物学的不断发展,人们已逐步了解植物寄主与病原之间的相互作用及植物抗病的分子机理。植物受病原侵染后出现两种类型的卫反应：局部防卫反应（过敏反应）和系统获得性防卫反应。本质素、植保素、活性氧、水杨酸等物质已被证明了在植物抗病中起了重要作用。抗病基因和防卫基因的诱导表达构成了防卫反应的遗传基础。本文综述了近年来抗病的分子生物学研究进展,并对其发展和应用前景作了展望。     

A transgenic perspective on plant functional genomics

Transgenic crops are very much in the news due to the increasing public debate on their acceptance. In the scientific community though, transgenic plants are proving to be powerful tools to study various aspects of plant sciences. The emerging scientific revolution sparked by genomics based technologies is producing enormous amounts of DNA sequence information that, together with plant transformation methodology, is opening up new experimental opportunities for functional genomics analysis. An overview is provided here on the use of transgenic technology for the functional analysis of plant genes in model plants and a link made to their utilization in transgenic crops. In transgenic plants, insertional mutagenesis using heterologous maize transposons or Agrobacterium mediated T-DNA insertions, have been valuable tools for the identification and isolation of genes that display a mutant phenotype. To discover functions of genes that do not display phenotypes when mutated, insertion sequences have been engineered to monitor or change the expression pattern of adjacent genes. These gene detector insertions can detect adjacent promoters, enhancers or gene exons and precisely reflect the expression pattern of the tagged gene. Activation tag insertions can mis-express the adjacent gene and confer dominant phenotypes that help bridge the phenotype gap. Employment of various forms of gene silencing technology broadens the scope of recovering knockout phenotypes for genes with redundant function. All these transgenic strategies describing gene-phenotype relationships can be addressed by high throughput reverse genetics methods that will help provide functions to the genes discovered by genome sequencing. The gene functions discovered by insertional mutagenesis and silencing strategies along with expression pattern analysis will provide an integrated functional genomics perspective and offer unique applications in transgenic crops. This revised version was published online in August 2006 with corrections to the Cover Date.     

Metabolic engineering of plant secondary products

Plants interact with their environment by producing a diverse array of secondary metabolites. Many of these compounds are valued for their medicinal, industrial or agricultural properties. Other secondary products are toxic or otherwise undesirable and can reduce the commercial value of crops. Gene transfer technology offers new opportunities to modify directly plant secondary product synthesis through metabolic engineering. This article reviews some of the strategies which have been used to increase or decrease the synthesis of specific plant metabolites, as well as methods for expanding the biosynthetic capabilities of individual species.     

植物丝氨酸羧肽酶及其类蛋白的研究进展

丝氨酸羧肽酶（serine carboxypeptidases,SCP）是一类属于α/β水解酶家族的蛋白酶,在植物生长发育过程中参与多肽和蛋白质的加工、修饰与降解等多个重要环节,并且在许多生化途径包括次生代谢产物的生物合成、催化酰基转移、除草剂共轭和种子萌发相关蛋白质降解中起重要作用。介绍和评述了植物丝氨酸羧肽酶及其类蛋白的种类、特点、功能及其基因的表达调控,并对植物丝氨酸羧肽酶及其类蛋白的研究方向和应用提出了展望。     

Regulation of the plant defence response in arbuscular mycorrhizal symbiosis

The response of plants to arbuscular mycorrhizal fungi involves a temporal and spatial activation of different defence mechanisms. The activation and regulation of these defences have been proposed to play a role in the maintenance of the mutualistic status of the association, however, how these defences affect the functioning and development of arbuscular mycorrhiza remains unclear. A number of regulatory mechanisms of plant defence response have been described during the establishment of the arbuscular mycorrhizal symbiosis, including elicitor degradation, modulation of second messenger concentration, nutritional and hormonal plant defence regulation, and activation of regulatory symbiotic gene expression. The functional characterization of these regulatory mechanisms on arbuscular mycorrhiza, including cross-talk between them, will be the aim and objective of future work on this topic.     

Proteomic dissection of plant responses to various pathogens

During their growth and development, plants are vulnerable to the effects of a variety of pathogens. Proteomics technology plays an important role in research studies of plant defense mechanisms by mining the expression changes of proteins in response to various biotic stresses. This review article provides a comprehensive overview of the latest developments in international proteomic research on plant biotic stress. It summarizes the methods commonly used in plant proteomic research to investigate biotic stress, analyze the protein responses of plants in adverse conditions, and reviews the applications of proteomics combined with transgenic technology in plant protection.     

约翰·韦伯斯特:来自植物病理学家的赞赏（英文）

<正>Appropriately for a man whose name is so closely associated with aquatic fungi,John Webster first came my way under water.I quite literally bumped into him when he was a large semi-submerged object barring my way across the swimming pool of a hall of residence at the University of South Florida,Tampa.We were both there as delegates to the Sec-     

Applications of DNA genetic markers to the study of plant growth and development

DNA genetic markers, such as restriction fragment length polymorphisms (RFLPs) and random amplified polymorphic DNA markers (RAPDs), are powerful tools for studying the genetics of plant growth and development. DNA markers are defined sequences of DNA that can be used in traditional linkage mapping. Using DNA marker technology, scientists can uncover relationships between cloned cDNA sequences and classically characterized genes. DNA markers make it possible to dissect the contributions of multiple genetic loci underlying complex developmental processes. Moreover, changes in genome organization that occur during development or in response to environmental signals can be monitored using RFLP technology. In the future, it may be possible to clone any gene based solely on its map position. This will involve the use of tightly linked DNA markers as entry points for chromosome walking, in which a series of overlapping genomic clones reaching from the tightly linked DNA marker to the gene of interest are identified.     

Chasing the dream: plant EST microarrays

DNA microarray technology is poised to make an important contribution to the field of plant biology. Stimulated by recent funding programs, expressed sequence tag sequencing and microarray production either has begun or is being contemplated for most economically important plant species. Although the DNA microarray technology is still being refined, the basic methods are well established. The real challenges lie in data analysis and data management. To fully realize the value of this technology, centralized databases that are capable of storing microarray expression data and managing information from a variety of sources will be needed. These information resources are under development and will help usher in a new era in plant functional genomics.     

Laser Microdissection (LM): Applications to plant materials

Abstract

In recent years, Laser Microdissection (LM), which has been widely used in animal biology, has been adapted to plant tissues. This short paper focuses on some technical aspects concerning plant sample preparation for LM technology, with particular attention to the application of gene expression and proteomics studies. Examples derived from the use of different LM methods are reported and their applications to plant–microbe interactions are explored.