钙信号系统与植物激素信号

Ca2+是高等植物细胞内普遍存在的一种信使分子,能介导植物对外界信号的刺激反应,调节多种生理过程, 并参与植物体内多种刺激-反应的藕联过程。目前证实在植物里钙依赖性蛋白激酶（CDPKs）、钙调素（CaM）、钙调磷酸酶B类似蛋白（CBLs）三类钙结合蛋白,这些蛋白质可识别特定的钙签名,并依赖这些钙信号向下游转达以适应外界刺激。Ca2+信使系统与激素在植物的花发育(成花诱导、花芽分化及开花调控),有性生殖方面(在花粉萌发和花粉管生长),逆境生理等都起着非常重要的作用。近些年有关学者在植物激素受体蛋白、信号转导、基因表达等方面的研究,以及与Ca2+相关的信号传递机理的研究中发现：Ca2+/CaM、Ca2+/CDPK和Ca2+/CBL三类钙信号系统与植物激素信号密切相关。     

北京市农林科学院揭示钙网蛋白BrCRT2在大白菜干烧心抗性中的作用新机制

<正>近日,北京市农林科学院蔬菜中心张凤兰课题组(十字花科作物遗传进化与育种)在Plant, CellEnvironment(影响因子5.624)在线发表了研究论文。该研究分析了钙网蛋白BrCRT2在大白菜干烧心抗性中的作用,阐述了BrCRT2参与植物胞质Ca2+浓度调控的新机制。大白菜原产我国,是我国栽培面积最大的蔬菜作物。干烧心病是由于缺钙(Ca2+)引起的生理性病害。目前生产     

丹参钙调蛋白cDNA的克隆及其反义表达载体的构建

丹参是著名的传统中药,对心血管疾病和癌症有广泛的疗效。钙调蛋白是细胞信号转导途径中的重要蛋白,在各种生理活动中起着重要的作用,其序列比较保守。国内外对中药丹参的分子学研究很少,本文利用分子生物学手段克隆了丹参钙调蛋白基因。从丹参成熟叶片中提取总RNA,cDNA第一链经反转录合成,利用设计的引物,PCR扩增,得到丹参钙调蛋白基因,测定其全序列。在GeneBank进行了注册。其次构建了丹参钙调蛋白基因反义表达载体,以后可进行基因敲除。通过Southern杂交,进行拷贝数推测,丹参钙调蛋白cDNA至少为2个拷贝。序列分析结果表明:得到的丹参钙调蛋白基因具有完整地读码框,由454个核苷酸组成,编码150个氨基酸。与别的植物钙调蛋白基因相比有很高的同源性,核苷酸序列同源性在80%以上,编码的氨基酸序列同源性在80%以上。以上结果能使我们更加深入地研究和了解钙调蛋白。     

钙信号在植物抗病性中的作用研究进展

在植物信号转导途径中,钙离子作为第二信使,参与调控了大多数细胞生理代谢的过程。大量实验研究表明,钙信号同时参与植物与病原菌互作的信号转导过程。综述了近几年来植物在抗病反应过程中钙信号的产生、起到的作用及下游靶蛋白是如何解码的,并就存在的问题做出了展望。     

聚合酶链式反应扩增甘蔗钙调蛋白基因及其序列分析

从甘蔗茎顶端分生组织提取点ＲＮＡ,反转录合成ｃＤＮＡ第一条链,以此为模板,参考大麦钙调蛋白基因序列设计并合成５端和３端引物,ＰＣＲ扩增甘蔗钙调蛋白基因,与克隆载体ｐＧＥＭ－３Ｚｆ（＋）重组,转化Ｅ．ｃｏｌｉＨＢ１０１得到得组克隆。ＤＮＡ序列分析结果表明：甘蔗钙调蛋白基因同４５０个核甘酸组成,编码１４８个氨基酸;在核甘酸序列上与迄今知道的几种植物的钙调蛋白基因有很高的同源性,同源率在８０％以上,编码     

钙在植物营养中的作用分析

在植物生长过程中,钙是不可或缺的营养元素,其是维持植物生理的功能。目前,钙已不仅仅是营养物质,同样也是对细胞功能进行调节的主要物质之一,确保植物体内代谢活动处于正常状态。因此,钙在植物营养中的作用不容小觑。基于此,将钙作为主要研究内容,重点阐述了其在植物营养中的重要作用,以供参考。     

盐碱胁迫下植物生理和钙信号通路分子机制的研究进展

土壤的盐化和碱化往往伴随发生,在盐碱胁迫下,植物会遭受许多类型的非生物胁迫,严重影响植物的正常生长发育。本综述首先介绍了盐碱土的分类;其次从四个方面对植物在盐碱胁迫下体内产生相应生理机制进行详细介绍;接下来以植物在盐碱胁迫下产生的钙信号为重点进行阐述,包括植物首个非离子通道型盐胁迫下离子感受器GIPCs的发现、盐碱胁迫诱导的钙信号相关通道和转运蛋白、钙信号的感受与传递、以及其他与钙离子信号产生交叉的信号通路的研究进展。在碱胁迫中与钙信号的相关研究鲜有报道,本综述也介绍了此方面的最新研究。最后,对该研究领域目前需要解决的科学问题进行展望。     

科技与产品

<正>张凤兰课题组揭示钙网蛋白Br CRT2在大白菜干烧心抗性中的作用新机制近日,北京市农林科学院蔬菜中心张凤兰课题组(十字花科作物遗传进化与育种)在Plant, CellEnvironment(影响因子5.624)在线发表了研究论文。该研究分析了钙网蛋白BrCRT2(Calreticulin2)在大白菜干烧心抗性中的作用,阐述了Br CRT2参与植物胞质Ca2+浓度调控的新机制。     

促生菌调控钙代谢相关基因家族成员以提高拟南芥高钙胁迫抗性

植物中存在包括钙调蛋白(CaM)、钙依赖性蛋白激酶(CDPK)、钙调神经磷酸酶B亚基样蛋白(CBL)和环核苷酸门控通道(CNGC)等参与钙信号传导的基因家族。本研究旨在探讨拟南芥钙代谢相关基因家族在高钙胁迫响应中的作用,以及解淀粉芽孢杆菌LZ04对这些基因的调控作用。我们发现,解淀粉芽孢杆菌LZ04可提高拟南芥对高钙胁迫的抗性。在拟南芥基因组中共检测到钙代谢相关基因家族104个基因,包括34个CDPK基因、20个CNGC基因、18个CIPK基因、22个IQD基因和10个CBP基因。104个钙代谢相关基因在染色体上的分布不均匀且外显子数目丰富。解淀粉芽孢杆菌LZ04通过调控钙代谢相关基因家族中的部分成员,增强了拟南芥对高钙胁迫的抗性。功能富集分析显示,第42号表达谱中聚集的基因在蛋白磷酸化和蛋白修饰过程中富集,可能是淀粉芽孢杆菌LZ04在高钙胁迫下的调控基因。这些结果对高钙胁迫地区的农业改良有一定的参考价值。     

钙信号与植物低温响应研究进展

钙信号是一种重要的第二信使,在动植物生长发育和信号转导中具有重要的调节作用。为了深入了解其参与植物低温响应的作用机理,笔者归纳了钙离子转运系统和相关钙离子感受器的结构和功能,并从生理变化和基因表达2个方面分析了钙信号参与植物低温响应的研究进展;总结了Ca~(2+)转运系统、Ca M、CMLs、CBLs和CDPKs中参与植物低温响应的基因,并简要分析了其作用机制。分析表明钙信号能通过多条途径增强植物的低温抗性,在农业生产中具有重要的现实意义。     

植物细胞中瞬时表达系统的建立及研究进展

摘 要：瞬时表达是近年来发展的一种快速、高效的检测蛋白质表达的方法,并逐渐被应用到生物学各方面的研究中。植物细胞瞬时表达系统的建立为方便、快捷的研究启动子活性、基因功能和蛋白质定位等开辟了新途径。本文主要归纳了植物瞬时表达系统的建立和发展过程,总结了近年来的应用以及对生物学研究的意义,并指出了该系统在当前应用中存在的不足,并针对这些不足提出了合理的建议。最后,本文结合最新的研究进展,对瞬时表达系统在分子细胞生物学、蛋白质组学、病毒学等方面的研究工作做了展望。     

甘蔗ScCRT1基因克隆及其应答SCMV侵染分子机制的研究

钙网蛋白(calreticulin,CRT)在真核生物中广泛表达,是重要的分子伴侣和钙离子结合蛋白,参与调控Ca2+稳态、钙依赖信号、内质网质量控制、植物生长发育、免疫反应和逆境应答等多种生物学过程。甘蔗(Saccharum spp.hybrid)中CRT应答甘蔗花叶病毒(Sugarcane mosaic virus,SCMV)侵染尚未见报道。本研究从热带种Badila(S.officinarum)中克隆了1个CRT1/CRT2亚型的CRT编码基因,命名为ScCRT1。该基因开放读码框(open reading frame,ORF)长度为1281bp,编码长度为426aa的蛋白。生物信息学分析表明,ScCRT1具有典型的CRT蛋白结构域,为稳定的亲水性蛋白,其N端有一个信号肽,具有典型的跨膜结构域,C端有典型的内质网定位信号;二级结构多为无规则卷曲;系统进化树分析表明,该蛋白是典型的CRT蛋白,在单子叶和双子叶植物中具有明显的分化。亚细胞定位表明ScCRT1定位于内质网。实时荧光定量PCR分析发现,ScCRT1基因在甘蔗各组织中都有表达,在第8节间中的表达量最低,在心叶中的表达量较高;该基因在SCMV侵染早期表达量上调,后期下调表达。酵母双杂交(yeast two hybrid,Y2H)和双分子荧光互补(bimolecular fluorescence complementation,BiFC)试验表明,ScCRT1与SCMV-6K2蛋白互作。推测SCMV-6K2通过与ScCRT1互作调控钙离子稳态进而便于SCMV侵染。     

拟南芥ERECTA基因的研究进展

ERECTA是从拟南芥La-0(Landsberg)中分离出来的一个类受体激酶,它可以与多种基因相互协作控制植物器官的形态建成。其拟南芥突变体Ler(Landsberg erecta)被广泛应用于分子遗传学研究。目前已有文章报道该基因在花序结构,叶片形态,气孔发育,抗病性等方面具有重要的作用。随着分子生物学与遗传学的发展,ERECTA基因新的功能被逐渐发现。本文综述了ERECTA基因在拟南芥的分生组织,叶,花以及生物与非生物胁迫等方面的功能。     

The National BioResource Project (NBRP) Lotus and Glycine in Japan

The objective of the National BioResource Project (NBRP) in Japan is to collect, conserve and distribute biological materials for life sciences research. The project consists of twenty-eight bioresources, including animal, plant, microorganism and DNA resources. NBRP Lotus and Glycine aims to support the development of legume research through the collection, conservation, and distribution of these bioresources. Lotus japonicus is a perennial legume that grows naturally throughout Japan and is widely used as a model plant for legumes because of such advantages as its small genome size and short life cycle. Soybean (Glycine max) has been cultivated as an important crop since ancient times, and numerous research programs have generated a large amount of basic research information and valuable bioresources for this crop. We have also developed a “LegumeBase” a specialized database for the genera Lotus and Glycine, and are maintaining this database as a part of the NBRP. In this paper we will provide an overview of the resources available from the NBRP Lotus and Glycine database site, called “LegumeBase”.     

Proteomics: a promising approach to study biotic interaction in legumes. A review

Summary During the 1990s and early 2000s, the genomes of different organisms have been completely sequenced. Nowadays, biological research is directed to understand gene expression and function. Proteomics, understood as protein biochemistry on an unprecedented and high-throughput scale, is becoming a promising and active approach in this post-genomic period. However, its application to plants is still rather limited as compared to other biological systems. After having referred to the most recent plant proteomic reviews, we focused on legume proteomics including studies with the model species Medicago truncatula. This review is aimed at providing to non-proteomic specialists a global overview of what might be expected in entering this field.     

Retrotransposons - a major driving force in plant genome evolution and a useful tool for genome analysis

As a major part of most plant genomes, retrotransposons are distributed throughout the plant genome ubiquitously with high copy number and extensive heterogeneity. Various retrotransposon families with distinct structures differ in their distribution and roles among divergent plant species, due to unforeseen transposition activities. Regulation of transposition is relatively complex and three factors such as maintaining structure for none- or cis- or trans-acting transposition, being controlled by the host genome and induction by biotic and abiotic stress may contribute altering its transposition activity. The important roles of retrotransposons to modify genome size, remodel genome structure, and displace gene functions in the plant genome have been proven by a growing number of research studies till date, which indicates that retrotransposons are important driving force in genome evolution. For this review, we summarized the latest theoretic and practical research progresses on plant retrotransposons for their distribution, regulation of activity, the impact on the architecture of plant genomes, and put forward the future prospects.     

植物SWEET基因家族的研究进展

植物糖转运蛋白SWEET基因家族是近年来发现的一类重要的糖转运蛋白,通过调节糖分在植物体内的转运及分配等,进而在植物的生长发育、生理代谢、抗逆境胁迫等方面起着重要作用。不同物种中SWEET基因所表现的生物学功能不同,对植物生物生命活动起着重要影响。本研究报告了植物SWEET基因家族的蛋白结构、转运机制以及生物学功能的研究现状,旨在为进一步研究SWEET基因家族的其他结构与功能提供理论基础。     

甘蔗ScCRT1基因克隆及其应答SCMV侵染分子机制的研究

Calreticulin (CRT) is widely expressed in eukaryotes. As a molecular chaperone and a Ca²⁺ binding protein, CRT is involved in many biological pathways such as the regulation of calcium homeostasis, calcium-dependent signaling, endoplasmic reticulum quality control, plant growth and development, immunity and response to stress. However, the response of CRT of sugarcane (Saccharum spp. hybrid) challenged by Sugarcane mosaic virus (SCMV) has not been reported. In this study, a CRT gene was cloned from the noble cane cultivar Badila (S. officinarum) and designed as ScCRT1. ScCRT1 had an open reading frame (ORF) length of 1281 bp and encoded 426 amino acids. Bioinformatics analysis showed that ScCRT1 was a stable hydrophilic protein and possesses a signal peptide at the N-terminal, a typical transmembrane domain, and a typical endoplasmic reticulum location signal at the C-terminal. The secondary structure of ScCRT1 was composed of mostly random coils. Phylogenetic tree analysis indicated that ScCRT1 belonged to the CRT1/CRT2 subtype and was divergent between monocotyledons and dicotyledons. Subcellular location assays showed that ScCRT1 was mainly located in the endoplasmic reticulum. Real-time quantitative PCR analysis showed that ScCRT1 gene was extensively expressed in different tissues of sugarcane, with the highest expression in leaf roll and the lowest expression in the 8th internode. ScCRT1 gene was up regulated in the early stage of SCMV infection, but down regulated with time going. ScCRT1 interacted with the 6K2 from SCMV as confirmed by yeast two hybrid and bimolecular fluorescence complementation assays. Based on these foundlings, we speculated SCMV interfered the calcium homeostasis by the interaction of 6K2 with ScCRT1, thereby facilitating viral infection of sugarcane.     

Glucosinolate metabolism,functionality and breeding for the improvement of Brassicaceae vegetables

Unique secondary metabolites, glucosinolates (S-glucopyranosyl thiohydroximates), are naturally occurring S-linked glucosides found mainly in Brassicaceae plants. They are enzymatically hydrolyzed to produce sulfate ions, D-glucose, and characteristic degradation products such as isothiocyanates. The functions of glucosinolates in the plants remain unclear, but isothiocyanates possessing a pungent or irritating taste and odor might be associated with plant defense from microbes. Isothiocyanates have been studied extensively in experimental in vitro and in vivo carcinogenesis models for their cancer chemopreventive properties. The beneficial isothiocyanates, glucosinolates that are functional for supporting human health, have received attention from many scientists studying plant breeding, plant physiology, plant genetics, and food functionality. This review presents a summary of recent topics related with glucosinolates in the Brassica family, along with a summary of the chemicals, metabolism, and genes of glucosinolates in Brassicaceae. The bioavailabilities of isothiocyanates from certain functional glucosinolates and the importance of breeding will be described with emphasis on glucosinolates.     

植物草酸钙晶体的研究进展

畜牧业养殖作为农业发展的重要分支,对社会经济发展、人民生活水平的提高起着至关重要的作用。中国盐碱地分布广泛,东北、西北、华北等地区均有分布,且次生盐碱化日益加剧,严重影响牧草产量,限制了畜牧业养殖的可持续发展。发展新型畜牧业养殖,改造治理、充分利用不适宜放牧的盐碱地等闲置土地资源,不仅可以发展新型畜牧业养殖,同时对农业可持续发展、推动区域经济、促进生态环境的可持续发展具有重要意义。新近有研究表明草酸钙晶体与植物抗盐碱具有密切联系,并且对其合成与调控机制已经展开了一些研究。虽然其合成与降解机制尚不完全清楚,但已有研究表明草酸钙晶体在钙调节,植物保护、防御、结石病防治、离子平衡、食品安全、植物病虫防治、缓解逆境胁迫等方面具有重要作用。本研究通过梳理相关文献,对植物草酸钙晶体的分布特征,研究方法、合成机制、降解机制、生物功能等方面进行综述,以期对其潜在的应用价值提供理论基础。