Variations on conserved signaling pathways in biocontrol and development:G protein and MAPK genes of Trichoderma. atroviride and T. virens

Filamentous fungi employ conserved eukaryotic signaling pathway to detect and respond to environmental signals, including the presence of the host. Genetic experiment in which a particular signaling protein is lost, or its activity enhanced, have defined some of the function of heterotrimeric G proteins and MAP kinases in development and virulence. A hallmark of these studies is that orthologs in different species may have different functions. Antagonistic fungal-fungal interactions form …     

Study of signal transduction factors involved in mycoparasitic response of Trichoderma atroviride

Numerous Trichoderma spp. are mycoparasites and commercially applied as biological control agents against a large number of plant pathogenic fungi. The mycoparasitic interaction is host-specific and several research strategies have been applied to identify the main genes and compounds involved in the antagonist-plant-pathogen three-way interaction. During mycoparasitism, signals from the host fungus are recognised by Trichoderma, stimulating antifungal activities that are accompanied by mo…     

Applications of Trichoderma formulations in crop protection

The choice of active Trichoderma strains is important in designing effective and safe biocontrol applications. Many species of Trichoderma have multiple strategies for fungal antagonism and indirect effects on plant health, such as growth promotion, systemic resistance induction and fertility improvements. Some strains are powerful antibiotic producers, and their suitability for use in biocontrol systems must be carefully assessed. However, many other active strains have no antibiotic cap…     

Heterologous expression of the glucose oxidase gene in Trichoderma atroviride leads enhanced ability to attack phytopathogenic fungi and induction of plant systemic disease resistance

A transgenic strain of Trichoderma atroviride that expresses the Aspergillus niger glucose oxidase gene goxA under a homologous pathogen-inducible promoter (nag1) has been constructed, with the aim of increasing the ability of this biocontrol agent (BCA) to attack phytopathogenic fungi and enhance plant systemic disease resistance. The sporulation and growth rate of the transgenic progenies were similar to the wild-type strain P1. goxA expression occurred immediately after contact with the p…     

植物中异三体G蛋白结构与功能

综述了植物中异三体G蛋白结构与功能研究概况。总结了植物异三体G蛋白的类型与亚基结构,归纳了该种蛋白的生物化学功能、所涉及的信号通路和参与的多种植物激素信号的调控。     

Mechanisms involved in biocontrol and plant induced resistance by richoderma. asperellum (T. harzianum T-203)

Growing awareness of the environmental damage caused by the use of chemical substances for plant disease control in agriculture has raised the need to study biological alternatives, such as activating the defense response of plant crops by inducers not toxic to the environment. Trichoderma spp. are effective biocontrol agents for a number of soilborne pathogens, and are also known for their ability to enhance plant growth and to induce systemic resistance (ISR) in plants. In our laborator…     

Advances in biocontrol mechanism and application of Trichoderma spp. for plant diseases

Trichoderma spp.is a filamentous soil fungus known as an effective biocontrol agent of a range of important airborne and soilborne pathogens,it has universal distribution and economic importance.This article reviewed the researches on biocontrol mech- anism for plant diseases and application of Trichoderma spp.,especially Trichoderma harzianum in recent years.     

Are mycoparasitism and chitinase production species or isolate dependent in Trichoderma ?

The relationship between taxonomic status of Trichoderma spp., chitinase production in solid substrate fermentation (SSF) on four media and mycoparasitism in dual culture (confrontation assay)against four plant pathogenic fungi was studied. Seventy five Trichoderma isolates belonging to 35species have been screened. The plant pathogenic fungi used in confrontation assay were Botrytis cinerea , Fusarium oxysporum f. sp. dianthi , Rhizoctonia solani and Sclerotinia sclerotiorum . The SSF media contained wheat bran, crude chitin (from crab shells, SIGMA) and salt solutions. The best performing isolates in mycoparasitism tests were Trichoderma flavofuscum, T. harzianum, T.inhamatum, T. koningii and T. strigosum. Some isolates exhibiting good mycoparasitism produced chitinase in SSF only at low or medium level. In contrary there were isolates with excellent extracellular chitinase production but their biocontrol potential did not belong to the leading group.Statistical methods have been used to evaluate the data.……     

影响野蚕黑卵蜂寄主识别和接受的一些因素

对野蚕黑卵蜂寄主识别和接受的研究结果表明，野蚕黑卵蜂接受寄主除化学因子外，还与寄主卵的物理性状有关．野蚕黑卵蜂优先接受那些大小与其寄主卵相仿的人造卵，大于寄主卵的检验和接受率明显降低．在２５℃下，随着涂利它素人造卵保存时间的延长，野蚕黑卵蜂对其识别接受率有所下降，至４５天仍有８０％的人造卵对野蚕黑卵蜂有引诱作用，到６０天时有２３．３３％的人造卵有引诱作用．     

G蛋白在暗调控气孔运动中的作用

通过药理学试验和暗诱导调控的蚕豆叶片气孔运动变化分析,来证明异源三聚体GTP-结合蛋白(G蛋白)参与暗诱导的气孔关闭过程.结果表明,百日咳毒素能够阻止暗诱导的气孔关闭,而该效应同样可被H2O2清除剂维生素C、过氧化氢酶所实现.表明暗中活化的G蛋白水平较高,G蛋白与H2O2共同在暗诱导的气孔关闭中作为信号分子参与其中.     

植物G蛋白的种类及异三聚体G蛋白在植物细胞信号转导中的作用

近年来,植物G蛋白（包括异三聚体G蛋白、小G蛋白及超大G蛋白）的存在受到人们的普遍关注,同时它在细胞信号转导过程中起着重要作用,已成为人们研究信号调控的热点问题。阐述了已发现的植物G蛋白的种类,总结了异三聚体G蛋白在植物细胞信号转导中的作用。     

植物异三聚体G蛋白在细胞信号转导中的作用机制研究进展

对近年来植物异三聚体G蛋白在细胞跨膜信号转导过程中作用机制的研究进展进行了综述,重点阐述了植物异三聚体G蛋白在植物细胞信号转导、调节气孔运动、调控花粉萌发及花粉管伸长等方面的重要作用,展望了植物异三聚体G蛋白的研究前景及方向。     

降解多菌灵木霉菌株的分离及其生防与降解特性

从长期施用多菌灵的葡萄园土壤中分离纯化得到一株能够降解多菌灵的木霉(Trichoderma sp.)菌株Tr1.在以多菌灵为惟一碳源的无机盐培养基中培养14 d后,该菌株对多菌灵的降解率为45.74％.在无机盐培养基中添加少量氨源,可以提高木霉Tr1对多菌灵的降解率,尤其是添加0.1％酵母粉,降解率达到了66.57％.木霉Tr1在含氮的无机盐培养基上的最适生长温度为28℃,最适初始pH为6.5.木霉Tr1还对所测定的6种植物病原真菌(Rhizoctonia solani,Phytophthora capsici,Verticillium dahliae Kleb,Phoma uvicola Berk,Bipolaris sorokiniana( Sacc.)hoemaker,Fusarium moniliforrne Sheld)都具有抑菌活性.该项研究为木霉在植物病害生物防治及多菌灵污染土壤修复方面的应用提供了基础.     

深绿木霉菌发酵代谢物与芸苔素内酯复配效果评价

研究了深绿木霉菌(Trichoderma atroviride)发酵代谢物与芸苔素内酯复配对辣椒、黄瓜、番茄、小青菜4种蔬菜种子萌发与生长的影响及对番茄灰霉病防治效果。结果表明,深绿木霉菌发酵代谢物稀释10、50、100倍后与0.1%芸苔素内酯稀释5 000倍液复配,对上述4种种子的发芽势及芽长有显著促生作用。深绿木霉菌发酵代谢物稀释50倍与0.1%芸苔素内酯稀释5 000倍液复配后浸种,可使番茄的株高、根长、鲜重、干重分别比对照提高20.00%、35.17%、59.20%、29.03%,同时对番茄灰霉病的防效达到56.62%。多组试验均表明,木霉菌发酵代谢产物与芸苔素内酯在促生及防病方面具有协同增效作用。     

Mechanisms involved in biocontrol and plant induced resistance by Trichoderna asperellun (T. harzianum T-203)

Growing awareness of the environmental damage caused by the use of chemical substances for plant disease control in agriculture has raised the need to study biological alternatives, such as activating the defense response of plant crops by inducers not toxic to the environment. Trichoderna spp. are effective biocontrol agents for a number of soilborne pathogens, and are also known for their ability to enhance plant growth and to induce systemic resistance (ISR) in plants.     

Quantification of the expression of chitinolytic enzyme encoding genes ech30, ech42 and nag1 in Trichoderma atroviride P1 under varying growth conditions using a real-time RT-PCR assay

The quantitative expression and the regulation of chitinase-encoding genes ech30, ech42 and nag1 in Trichoderma atroviride P1 under varying growth conditions were investigated using real-time RT-PCR, principle component and multivariate analyses. Twelve media combinations including 0.1% and 3% glucose as carbon source and no (0 mmol/L), low (10 mmol/L) and high (100 mmol/L) ammonium acetate as nitrogen source combined with or without colloidal chitin at 3 time intervals and 2 replicat…     

植物异三聚体G蛋白功能与相关机制研究进展

异三聚体G蛋白参与许多植物进程,包括种子萌发,茎的伸长,根的生长,果实发育以及植物对光,臭氧,激素,病原菌的反应等。文章就植物中异三聚体G蛋白偶联信号途径的研究进展作了综述,并重点讨论了植物异三聚体G蛋白的功能及相关机制。     

信号转导抑制剂对囊素刺激杂交瘤细胞抗体分泌及其mRNA表达的影响

以杂交瘤细胞为模型 ,在培养液中加入不同的信号转导抑制剂和囊素 ,用间接ELISA法测定抗体分泌水平 ,用定量RT PCR法检测抗体mRNA的表达水平。结果表明 ,加入Gα 蛋白选择性抑制剂NF 0 2 3、蛋白激酶C抑制剂GF10 92 0 3X、磷脂酰肌醇 3激酶抑制剂heparin、Ca2 /calmodulin依赖蛋白激酶Ⅱ抑制剂KN 6 2、磷脂酶C抑制剂U 7312 2和蛋白激酶G抑制剂后 ,囊素对杂交瘤细胞抗体分泌速度的影响明显 (P <0 0 1)。而加入蛋白激酶A抑制剂 4 Cyano 3 M thylisoquinoline、酪氨酸蛋白激酶抑制剂 genistein和丝裂原活化的蛋白激酶抑制剂PD 980 5 9后 ,囊素对杂交瘤细胞抗体分泌速度的影响不明显 (P >0 0 5 ) ,这 3种抑制剂对杂交瘤细胞抗体分泌速度的抑制率分别为 74 5 5 % ,91 13%和80 6 9%。加入 4 Cyano 3 M thylisoquinoline、genistein和PD 980 5 9后 ,囊素处理组与对照组γ1mRNA的表达水平差异不显著 (P >0 0 5 ) ,说明这 3种抑制剂阻断了囊素刺激的杂交瘤细胞抗体mRNA的表达。以上结果表明 ,蛋白激酶A、酪氨酸蛋白激酶和丝裂原活化的蛋白激酶参与了囊素在杂交瘤细胞中的信号转导。     

Plant mitogen-activated protein kinases and their roles in mediation of signal transduction in abiotic stresses

Mitogen-activated protein kinase (MAPK) cascade plays a central role in transfer information from diverse receptors/sensors to a wide range of cellular responses in plants. MAP kinases are organized into a complex network for efficient transmission of specific stimuli, including the abiotic stress signaling. In recent years, the mutants of loss-offunction and gain-of-function, and other additional tools are used to investigate the plant MAPK cascades. This review has summarized the recent progress on the MAPK cascade involved in mediation of the transduction of several pronounced abiotic stress signalings, such as salt, drought, low and high temperature, wound, hormone, and deficient nutrients. Currently, although part of the components of the MAPK cascade responding to the abiotic stresses have been identified, the integral molecular mechanisms of the abiotic stresses signaling transduction mediated viaMAPK cascade are largely unknown and need to be elucidated further in the future.     

黄曲条跳甲E型前列腺素受体cDNA的鉴定及表达谱研究

前列腺素(Prostaglandin,PG)的受体(E-Prostaglandin Receptors,EP)与细胞信号传导密切相关,对于昆虫免疫、生殖等具有重要意义。为促进重要蔬菜害虫黄曲条跳甲前列腺素受体的功能研究,结合转录组测序和荧光定量PCR等方法,分析了黄曲条跳甲PGE2受体EP(PsEP)的cDNA序列及基因表达情况。结果表明,PsEP的cDNA的开放阅读框为1 323 bp,编码323个氨基酸,含有典型的G-蛋白耦联受体家族1结构域,但其亚型分类还有待进一步验证。PsEP分子在成虫的多种组织器官中都有表达,但生殖系统和中肠相对较高。此外,雌雄之间对比发现,雄虫PsEP表达量均比雌虫对应组织器官的表达量要高。