A tomato cysteine protease required for Cf-2-dependent disease resistance and suppression of autonecrosis

Little is known of how plant disease resistance (R) proteins recognize pathogens and activate plant defenses. Rcr3 is specifically required for the function of Cf-2, a Lycopersicon pimpinellifolium gene bred into cultivated tomato (Lycopersicon esculentum) for resistance to Cladosporium fulvum. Rcr3 encodes a secreted papain-like cysteine endoprotease. Genetic analysis shows Rcr3 is allelic to the L. pimpinellifolium Ne gene, which suppresses the Cf-2-dependent autonecrosis conditioned by its L. esculentum allele, ne (necrosis). Rcr3 alleles from these two species encode proteins that differ by only seven amino acids. Possible roles of Rcr3 in Cf-2-dependent defense and autonecrosis are discussed.     

Cloning and functional analysis of the genes involved in signal transduction in tomato Cf-4-Avr4 pathosystem

Hypersensitive response (HR) is one of the most efficient and common resistance mechanisms in plants. Cloning signaling genes are very important to elucidate the resistance mechanisms. A gene in tomato homologous to several resistance proteins in plant was involved in HR and named as RGL (Resistance Gene Like). RGL protein was used as a bait to screen interacting protein(s) from tomato cDNA library through the yeast two-hybrid system. Two interacting proteins were found, which were called as RGLIP-1 and RGLIP-2 (RGL Interacting Protein), respectively. RGLIP-1 is a protein of 291 amino acids with significant homology with thylakoid lumen protein. RGLIP-2 is a protein of 248 amino acids with significant homology with transducin protein. Virus-Induced Gene Silencing (VIGS) of the two genes results in a partial and complete suppression of Avr4-induced HR, which indicates that both genes are involved in hypersensitive response. __________ Translated from Acta Horticulturae Sinica, 2006, 33(1): 52–57 [译自: 园艺学报]     

The Trichoderma-plant interaction is mediated by avirulence proteins produced by this fungus

The molecular basis of Trichoderma -plant interaction is very complex and still not completely understood. The colonization of the root system by rhizosphere competent strains of Trichoderma results in increased development of root/aerial systems, in improved yields and in plant disease control. Other beneficial effects, such as the induction of plant systemic resistance, have also been described. To understand the mechanisms involved we are using different approaches, including the making…     

番茄Cf-5基因的SNP分子标记开发

根据已知的叶霉病抗性基因Cf-5基因序列,设计了3对嵌套引物。以4份抗病材料和4份非抗病材料DNA为模板,扩增番茄Cf-5基因并比较了抗感材料Cf-5基因的序列,在580、2 879 bp位点分别有T与C、G与T的碱基替换,设计了等位基因特异引物,获得了稳定的等位基因PCR产物,成功地开发了抗叶霉病基因Cf-5的SNP标记,为培育抗叶霉病番茄品种奠定了基础。     

Cleavage of Arabidopsis PBS1 by a bacterial type III effector

Plant disease-resistance (R) proteins are thought to function as receptors for ligands produced directly or indirectly by pathogen avirulence (Avr) proteins. The biochemical functions of most Avr proteins are unknown, and the mechanisms by which they activate R proteins have not been determined. In Arabidopsis, resistance to Pseudomonas syringae strains expressing AvrPphB requires RPS5, a member of the class of R proteins that have a predicted nucleotide-binding site and leucine-rich repeats, and PBS1, a protein kinase. AvrPphB was found to proteolytically cleave PBS1, and this cleavage was required for RPS5-mediated resistance, which indicates that AvrPphB is detected indirectly via its enzymatic activity.     

真菌无毒基因克隆与抗性蛋白互作研究

无毒基因（avirulence genes, Avr）是病原物遗传因子,能诱发寄主植物产生抗病性。真菌Avr基因的克隆、编码产物结构和功能分析,以及与寄主抗性蛋白的互作机制等方面的研究对于深入了解植物的抗真菌病害分子机理具有重要意义。其编码AVR蛋白（又可以称为效应子,effector）通常富含半胱氨酸,效应子通过吸器或侵入丝被分泌到寄主细胞内促发抗性反应。在抗性反应过程中,效应子能直接或间接地被植物细胞相应的抗性蛋白识别,这种识别机制与效应子和抗性蛋白的区段相关。以几个真菌病害为例,综述了近年来有关无毒基因克隆、表达、以及与抗性蛋白的互作机制等方面的主要研究进展,以期为相关研究的深入提供参考。     

Development of Molecular Marker Linked to Cf-10 Gene Using SSR and AFLP Method in Tomato

The leaf mould resistance gene Cf-10 on tomato confered resistant or immune to all prevalent physiological races of Cladosporium fulvum presented in three northeastern provinces of China in inoculation...     

盐胁迫下不同盐敏感型番茄在蛋白质表达上的差异

研究了耐盐与不耐盐番茄自交系在盐胁迫与正常栽培条件下根中蛋白质表达上的差异。耐盐番茄根系中蛋白质含量高于不耐盐番茄，正常栽培条件下番茄根系蛋白质含量高于盐处理番茄。蛋白质提取液不但在总蛋白质数量上有所不同，而且在蛋白质种类上亦有所差异。经过不同的双向凝胶电泳分离后，经过PD Quest软件和Q—TOF质谱分析结果为，在盐胁迫条件下共有8种蛋白质在表达上差异显著。磷酸葡萄糖脱氢酶、乙醇脱氢酶催化和3-异戊基苹果酸脱氢酶在盐处理的耐盐番茄根系中显著增加，异戊烯二磷酸(IDP)异构酶显著减少。     

Coupling of stress in the ER to activation of JNK protein kinases by transmembrane protein kinase IRE1

Malfolded proteins in the endoplasmic reticulum (ER) induce cellular stress and activate c-Jun amino-terminal kinases (JNKs or SAPKs). Mammalian homologs of yeast IRE1, which activate chaperone genes in response to ER stress, also activated JNK, and IRE1alpha-/- fibroblasts were impaired in JNK activation by ER stress. The cytoplasmic part of IRE1 bound TRAF2, an adaptor protein that couples plasma membrane receptors to JNK activation. Dominant-negative TRAF2 inhibited activation of JNK by IRE1. Activation of JNK by endogenous signals initiated in the ER proceeds by a pathway similar to that initiated by cell surface receptors in response to extracellular signals.     

基于 TMT和PRM 技术筛选番茄响应盐胁迫差异表达蛋白

【目的】 盐胁迫是造成番茄产量损失和品质严重下降的关键非生物胁迫之一,研究番茄耐盐的分子机制,为认识番茄幼苗应答盐胁迫分子调控机制奠定基础。【方法】 研究利用番茄耐盐渐渗系IL-7-5-5和番茄盐敏感M82为试材,采用同位素相对标记与绝对定量(TMT)技术结合定量蛋白质组平行反应监测(PRM)技术,对200 mM盐胁迫12 h的番茄幼苗叶片进行蛋白质组学研究,筛选出盐胁迫响应显著的潜在靶标蛋白。【结果】 (1)共鉴定出286个差异显著表达蛋白(DEPs)。盐胁迫下IL-7-5-5鉴定到191个DEPs,其中119个表达上调,72个表达下调。在M82中鉴定出157个DEPs,其 中84个表达上调,73个表达下调。维恩图分析显示,有129和95个差异蛋白分别特异于IL-7-5-5和M82。有62个显著差异蛋白共表达,其中 28 个在IL-7-5-5和M82中均上调,15 个均为下调,表现出对盐胁迫的一致响应。19个显著差异蛋白在表达相反,有5个蛋白质在ST中下调,在SS中上调,14个差异蛋白在ST中上调,在SS中下调;(2)番茄盐反应蛋白种类诱导能力强,主要与代谢过程、单组织过程以及细胞过程有关,细胞组成主要涉及细胞、细胞器、分子复合物和膜,基因本体分子功能显示,这些差异性蛋白主要参与催化活性、绑定和分子功能调控。(3)选择11个显著差异蛋白PRM验证结果与TMT 定量表现出相同的趋势。差异蛋白包括 A0A3Q7E8T9、A0A3Q7EK65、A0A3Q7FY19、A0A3Q7G430、A0A3Q7ITH0、A0A3Q7J1Y7、P05116、Q43779、A0A3Q7F8W6、A0A3Q7GKU3、A0A3Q7J0Z4,可能是番茄幼苗耐盐的潜在靶标蛋白。【结论】 研究采用 TMT 结合 PRM 技术,筛选出番茄幼苗响应盐胁迫差异表达蛋白。     

Signaling of rat Frizzled-2 through phosphodiesterase and cyclic GMP

The Frizzled-2 receptor (Rfz2) from rat binds Wnt proteins and can signal by activating calcium release from intracellular stores. We show that wild-type Rfz2 and a chimeric receptor consisting of the extracellular and transmembrane portions of the beta2-adrenergic receptor with cytoplasmic domains of Rfz2 also signaled through modulation of cyclic guanosine 3',5'-monophosphate (cGMP). Activation of either receptor led to a decline in the intracellular concentration of cGMP, a process that was inhibited in cells treated with pertussis toxin, reduced by suppression of the expression of the heterotrimeric GTP-binding protein (G protein) transducin, and suppressed through inhibition of cGMP-specific phosphodiesterase (PDE) activity. Moreover, PDE inhibitors blocked Rfz2-induced calcium transients in zebrafish embryos. Thus, Frizzled-2 appears to couple to PDEs and calcium transients through G proteins.     

罗尔斯通氏菌菌株H16新杀虫蛋白的纯化及活性测定

利用(NH4)2SO4盐析、超滤、Sephacryl-400HR凝胶过滤层析及DEAE-Sephadex A-50阴离子交换层析等方法,从罗尔斯通氏菌菌株H16(Ralstonia eutropha H16)中分离纯化出一种新的杀虫毒素蛋白.生物活性测定结果表明,此杀虫毒素蛋白存在于胞内和胞外上清液中,电泳结果显示胞内和分泌到胞外的杀虫毒素可能是同一种物质.此毒素对菜青虫初孵幼虫有较强的口服毒性,LD50为2.7mg/头.SDS-PAGE图谱显示此杀虫毒素是由两个亚基组成的复合蛋白.     

Effects of Ca2+/CaM Messenger System Inhibitors on Ethylene-Induced Increase in Lycopene Content

The changes of lycopene content during ripening and senescence of tomato fruit and the relationship between ethylene glycol-bis (EGTA, Ca2+ chelator), verapamil (Vp, Ca2+ channel blockers), trifluoperazine (TFP), chloropromaize (CPZ) (CaM antagonism) and ethylene-induced increase in lycopene content in tomato fruit were investigated. Lycopene content accumulated obviously during ripening and senescence of tomato fruit after harvest at pink stage. Low temperature inhibited but ethylene enhanced the lycopene content.Meanwhile, ethylene also promoted calmodulin (CaM) content in tomato fruit, which was related to the concentration of ethylene. When EGTA, Vp, TFP and CPZ with ethylene were used to treat tomato fruit, ethylene-induced increase in lycopene content could be reversed, indicating that blocking Ca2+ channel in plasma membrane or chelating extracellular Ca2+ or inhibiting the activity of CaM could decrease the action of ethylene, and suggesting that Ca2+-CaM messenger system may be involved in lycopene increase inducedby ethylene.     

蛋白质组学在番茄非生物逆境胁迫中的研究进展

【目的】回顾近年来蛋白质组学在番茄逆境胁迫中的研究进展,综述蛋白质组学技术在番茄响应非生物(盐碱、干旱、高温、低温、其它)胁迫上的研究进展,为利用蛋白质组学技术进一步研究番茄响应非生物逆境胁迫的分子机制奠定理论基础。【方法】运用统计学方法收集文献资料,并分析汇总蛋白质组学技术在番茄响应非生物(盐碱、干旱、高温、低温等)胁迫的研究文献进展情况。【结果】盐胁迫耐受性(渗透调节,渗透保护,离子稳态,消除氧清除剂,胁迫反应等)与胁迫的持续时间有关;下调的蛋白主要参与代谢和能量转换,上调的蛋白参与信号转导或运输;干旱应答蛋白包括与耐热性和渗透性保护剂的产生、脂质代谢、细胞壁修饰、神经酰胺代谢和丝裂原活化蛋白磷酸化相关的蛋白;蛋白质广泛参与了细胞过程,包括防御/应激反应,离子结合/转运,光合作用和蛋白质合成;最初如何感知胁迫条件,以及植物器官激活了哪些主要反应,可以避免低温胁迫晚期相关蛋白的干扰。【结论】在非生物逆境胁迫条件下,番茄通过改变自身的蛋白质表达水平对各种非生物胁迫作出响应。蛋白质组学研究能够全面揭示番茄响应胁迫时其细胞内蛋白质的动态变化规律,鉴定差异表达的蛋白质,是番茄抗逆生物学研究的重要组成部分。     

番茄CKX基因家族生物信息学分析

植物细胞内的细胞分裂素受到细胞分裂素脱氢酶/氧化酶(Cytokinin oxidase/dehydrogenase,CKX)的调节,来维持植物体内细胞分裂素动态平衡。为探究番茄基因组中CKX基因(SlCKX)家族成员的信息,本研究通过现代生物信息学分析,对番茄中CKX基因家族进行鉴定和分析。结果表明,在番茄全基因组中鉴定出9个CKX基因家族成员,蛋白长度在453~553氨基酸之间,编码蛋白分子量在51660.72~52493.64kDa之间,为亲水性蛋白;番茄CKX基因分在4个亚族内,并且SlCKX家族成员中含有3~5的内含子以及4~6外显子;9个番茄CKX家族基因不均匀的分布在5条染色体上,番茄CKX基因家族包含11种顺式作用元件,其中分布最广的为脱落酸响应元件。该研究将为番茄CKX基因家族的功能和应用研究提供一定的理论依据。     

BSKs mediate signal transduction from the receptor kinase BRI1 in Arabidopsis

Brassinosteroids (BRs) bind to the extracellular domain of the receptor kinase BRI1 to activate a signal transduction cascade that regulates nuclear gene expression and plant development. Many components of the BR signaling pathway have been identified and studied in detail. However, the substrate of BRI1 kinase that transduces the signal to downstream components remains unknown. Proteomic studies of plasma membrane proteins lead to the identification of three homologous BR-signaling kinases (BSK1, BSK2, and BSK3). The BSKs are phosphorylated by BRI1 in vitro and interact with BRI1 in vivo. Genetic and transgenic studies demonstrate that the BSKs represent a small family of kinases that activate BR signaling downstream of BRI1. These results demonstrate that BSKs are the substrates of BRI1 kinase that activate downstream BR signal transduction.     

分蘖洋葱-番茄套作系统中番茄叶片差异蛋白表达分析

【目的】明确套作对番茄叶片差异蛋白表达的影响,从蛋白质水平进一步揭示套作分蘖洋葱减轻番茄连作障碍的机理,探明套作控病增产的原因,推动番茄高效优质栽培模式的建立和推广。【方法】以番茄为主栽作物,分蘖洋葱为套作作物,番茄叶片为试材,将4个不同化感潜力的分蘖洋葱品种（化感潜力强的‘绥化’和‘五常红七社’,化感潜力弱的‘宁安市红城村’和‘七台河’）与番茄套作,运用蛋白质双向电泳和MALDI-TOF-MS质谱鉴定技术,鉴定套作不同化感潜力分蘖洋葱对番茄叶片蛋白质表达谱的变化,分析差异蛋白的种类和功能。【结果】套作后不同处理番茄叶片共鉴定出39个差异表达蛋白,分为7类,包括光合作用相关蛋白、代谢相关蛋白、能量代谢相关蛋白、植物抗性相关蛋白、蛋白质合成相关蛋白、核酸合成相关蛋白和未知功能蛋白,差异较大的是与光合（11个）、代谢（11个）、植物抗性（8个）相关的蛋白。套作处理后,热激蛋白、硫氧还蛋白、多酚氧化酶、景天庚酮糖-1,7-二磷酸酶、S-腺苷硫氨酸脱氢酶、ATP结合蛋白在番茄叶片中的表达量均有不同程度上调,化感潜力强的品种表达量显著高于弱的品种。【结论】套作分蘖洋葱对番茄叶片的蛋白表达存在差异,且化感潜力强的品种差异蛋白表达量高于化感潜力弱的品种,表明套作化感潜力强的品种有利于促进番茄的生长,增强其抗逆性,从而减轻连作障碍。     

利用无致病力青枯菌株防治番茄青枯病的研究

自发突变的无致病力番茄青枯菌株Ｔｍ３具有产生细菌素的能力,对番茄青枯菌株Ｔｍ４６有较强的抑菌作用,且能诱导烟草植株产生过敏性反应。盆栽和小区试验结果表明,Ｔｍ３具有较好的防治番茄青枯病的能力。防病机理可能是细菌素的抗生素和诱导植物抗病性的双重作用。