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Giles E D Oldroyd - One of the best experts on this subject based on the ideXlab platform.
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rhizobial and mycorrhizal symbioses in lotus japonicus require lectin nucleotide phosphohydrolase which acts upstream of calcium signaling
Plant Physiology, 2013Co-Authors: N Roberts, Giles E D Oldroyd, Gurpreet Kalsi, Peter M Gresshoff, Jiri Stiller, Anne Edwards, Giulia Morieri, Alan B Rose, Fang Xie, Allan J DownieAbstract:Nodulation in legumes requires the recognition of rhizobially made Nod Factors. Genetic studies have revealed that the perception of Nod Factors involves LysM domain receptor-like kinases, while biochemical approaches have identified LECTIN NUCLEOTIDE PHOSPHOHYDROLASE (LNP) as a Nod Factor-binding protein. Here, we show that antisense inhibition of LNP blocks Nodulation in Lotus japonicus. This absence of Nodulation was due to a defect in Nod Factor signaling based on the observations that the early Nodulation gene NodULE INCEPTION was not induced and that both Nod Factor-induced perinuclear calcium spiking and calcium influx at the root hair tip were blocked. However, Nod Factor did induce root hair deformation in the LNP antisense lines. LNP is also required for infection by the mycorrhizal fungus Glomus intraradices, suggesting that LNP plays a role in the common signaling pathway shared by the rhizobial and mycorrhizal symbioses. Taken together, these observations indicate that LNP acts at a novel position in the early stages of symbiosis signaling. We propose that LNP functions at the earliest stage of the common Nodulation and mycorrhization symbiosis signaling pathway downstream of the Nod Factor receptors; it may act either by influencing signaling via changes in external nucleotides or in conjunction with the LysM receptor-like kinases for recognition of Nod Factor.
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gras proteins form a dna binding complex to induce gene expression during Nodulation signaling in medicago truncatula
The Plant Cell, 2009Co-Authors: Sibylle Hirsch, Allan J Downie, Jiyoung Kim, Alfonso Munoz, Anne B Heckmann, Giles E D OldroydAbstract:The symbiotic association of legumes with rhizobia involves bacterially derived Nod Factor, which is sufficient to activate the formation of Nodules on the roots of the host plant. Perception of Nod Factor by root hair cells induces calcium oscillations that are a component of the Nod Factor signal transduction pathway. Perception of the calcium oscillations is a function of a calcium- and calmodulin-dependent protein kinase, and this activates Nodulation gene expression via two GRAS domain transcriptional regulators, Nodulation Signaling Pathway1 (NSP1) and NSP2, and an ERF transcription Factor required for Nodulation. Here, we show that NSP1 and NSP2 form a complex that is associated with the promoters of early Nodulin genes. We show that NSP1 binds directly to ENod promoters through the novel cis-element AATTT. While NSP1 shows direct binding to the ENod11 promoter in vitro, this association in vivo requires NSP2. The NSP1-NSP2 association with the ENod11 promoter is enhanced following Nod Factor elicitation. Mutations in the domain of NSP2 responsible for its interaction with NSP1 highlight the significance of the NSP1-NSP2 heteropolymer for Nodulation signaling. Our work reveals direct binding of a GRAS protein complex to DNA and highlights the importance of the NSP1-NSP2 complex for efficient Nodulation in the model legume Medicago truncatula.
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Abscisic Acid Coordinates Nod Factor and Cytokinin Signaling during the Regulation of Nodulation in Medicago truncatula
The Plant Cell, 2008Co-Authors: Yiliang Ding, Jongho Sun, Péter Kaló, John F. Marsh, Jeanne M. Harris, Craig R. Yendrek, Yan Liang, Giles E D OldroydAbstract:Nodulation is tightly regulated in legumes to ensure appropriate levels of nitrogen fixation without excessive depletion of carbon reserves. This balance is maintained by intimately linking Nodulation and its regulation with plant hormones. It has previously been shown that ethylene and jasmonic acid (JA) are able to regulate Nodulation and Nod Factor signal transduction. Here, we characterize the nature of abscisic acid (ABA) regulation of Nodulation. We show that application of ABA inhibits Nodulation, bacterial infection, and Nodulin gene expression in Medicago truncatula. ABA acts in a similar manner as JA and ethylene, regulating Nod Factor signaling and affecting the nature of Nod Factor-induced calcium spiking. However, this action is independent of the ethylene signal transduction pathway. We show that genetic inhibition of ABA signaling through the use of a dominant-negative allele of ABSCISIC ACID INSENSITIVE1 leads to a hyperNodulation phenotype. In addition, we characterize a novel locus of M. truncatula, SENSITIVITY TO ABA, that dictates the sensitivity of the plant to ABA and, as such, impacts the regulation of Nodulation. We show that ABA can suppress Nod Factor signal transduction in the epidermis and can regulate cytokinin induction of the Nodule primordium in the root cortex. Therefore, ABA is capable of coordinately regulating the diverse developmental pathways associated with Nodule formation and can intimately dictate the nature of the plants' response to the symbiotic bacteria.
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Mastoparan activates calcium spiking analogous to Nod Factor-induced responses in Medicago truncatula root hair cells
Plant Physiology, 2007Co-Authors: Jongho Sun, Hiroki Miwa, J. Allan Downie, Giles E D OldroydAbstract:The rhizobial-derived signaling molecule Nod Factor is essential for the establishment of the Medicago truncatula / Sinorhizobium meliloti symbiosis. Nod Factor perception and signal transduction in the plant involve calcium spiking and lead to the induction of Nodulation gene expression. It has previously been shown that the heterotrimeric G-protein agonist mastoparan can activate Nodulation gene expression in a manner analogous to Nod Factor activation of these genes and this requires DOESN9T MAKE INFECTIONS3 ( DMI3 ), a calcium- and calmodulin-dependent protein kinase (CCaMK) that is required for Nod Factor signaling. Here we show that mastoparan activates oscillations in cytosolic calcium similar but not identical to Nod Factor-induced calcium spiking. Mastoparan-induced calcium changes occur throughout the cell, whereas Nod Factor-induced changes are restricted to the region associated with the nucleus. Mastoparan-induced calcium spiking occurs in plants mutated in the receptor-like kinases Nod Factor PERCEPTION and DMI2 and in the putative cation channel DMI1 , which are all required for Nod Factor induction of calcium spiking, indicating either that mastoparan functions downstream of these components or that it uses an alternative mechanism to Nod Factor for activation of calcium spiking. However, both mastoparan and Nod Factor-induced calcium spiking are inhibited by cyclopiazonic acid and n -butanol, suggesting some common mechanisms underpinning these two calcium agonists. The fact that mastoparan and Nod Factor both activate calcium spiking and can induce Nodulation gene expression in a DMI3 -dependent manner strongly implicates CCaMK in the perception and transduction of the calcium signal.
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analysis of Nod Factor induced calcium signaling in root hairs of symbiotically defective mutants of lotus japonicus
Molecular Plant-microbe Interactions, 2006Co-Authors: Hiroki Miwa, Giles E D Oldroyd, Allan J DownieAbstract:Nodulation (Nod)-Factor signaling molecules are essential for rhizobia to initiate the nitrogen-fixing symbiotic interaction with legumes. Using a dual dye ratiometric calcium imaging technique, we have shown that 10 nM Nod Factor added to roots of Lotus japonicus seedlings induces an intra-cellular calcium increase (calcium flux) that precedes oscillations in intracellular calcium (calcium spiking). The calcium flux was not observed with 1 or 0.1 nM Nod Factor, which did induce calcium spiking. The calcium flux was variable in timing of initiation and duration and was observed in approximately half of the root hairs examined. Representatives from 11 complementation groups of symbiotically defective mutants were analyzed for the calcium flux. Mutants from four groups (sym6, ccamk, sym35, and nin) which retained calcium spiking all showed a normal calcium flux. Two classes of mutants (nfr1 and nfr5) lacked both calcium influx and calcium spiking, whereas five classes of mutants (symRK, castor, pollux, nup1...
Donald L Smith - One of the best experts on this subject based on the ideXlab platform.
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Nod Factor Nod bj v c18 1 mefuc and lumichrome enhance photosynthesis and growth of corn and soybean
Journal of Plant Physiology, 2008Co-Authors: Wajahatullah Khan, Balakrishnan Prithiviraj, Donald L SmithAbstract:The foliar application of Nod Factor [Nod Bj V (C 18:1 , MeFuc)] enhanced (P<0.05) the photosynthetic rate of corn; the increases were 36%, 23% and 12% for 10 -6 , 10 -8 and 10 -10 M treated plants, respectively. Similarly, lumichrome at 10 -5 and 10 -6 M stimulated the photosynthetic rate of corn plants 1 and 2 days after application. Lumichrome (10 -5 and 10 -6 M) also increased the photosynthetic rates of soybean plants 3 days after treatment. Foliar applications of LCO (10 -6 M) to corn and soybean and of lumichrome (10 -5 M) to soybean increased leaf area, shoot dry mass and total dry mass relative to control plants. However, lumichrome treatments did not affect any growth variable of corn. Results of this study indicate that this signal compound can enhance the photosynthetic rate and growth of plants.
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Nod Factor induces soybean resistance to powdery mildew.
Plant Physiology and Biochemistry, 2005Co-Authors: Haifa M Duzan, Fazli Mabood, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Plants possess highly sensitive perception systems by which microbial signal molecules are recognized. In the Bradyrhizobium-soybean (Glycine max (L.) Merr.) symbiosis, recognition is initiated through exchange of signal molecules, generally flavonoids from soybean and lipo-chitooligosaccharides (Nod Factors) from the microsymbiont. Application of the Nod Factor Nod Bj-V (C18:1, MeFuc) induced soybean resistance to powdery mildew caused by Microsphaera diffusa. Addition of Nod Factor (concentrations ranging from 10(-6) to 10(-10) M) to soybean root systems led to reductions in disease incidence. The lowest disease incidence was caused by Nod Factor treatment at 10(-6) M. The effect of Nod Factor application on fungal growth and development was measured at 4, 12, 48, and 96 h after inoculation. Colony diameter and number of germ tubes per conidium were decreased by 10(-6) M Nod Factor. Phenylalanine ammonia lyase (PAL, EC.4.3.1.1.) is the first enzyme of the phenyl propanoid pathway, and is commonly activated as part of plant responses to disease. Treatment of soybean seedlings with Nod Factor, through stem wounds, induced PAL activity; the most rapid increase followed treatment with 10(-6) M Nod Factor. These data show that soybean plants are able to detect root applied LCO and respond by increased disease resistance.
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perception of bradyrhizobium japonicum Nod Factor by soybean glycine max l merr root hairs under abiotic stress conditions
Journal of Experimental Botany, 2004Co-Authors: Haifa M Duzan, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Suboptimal growth conditions, such as low rhizosphere temperature, high salinity, and low pH can negatively affect the rhizobia–legume symbioses, resulting in poor Nodulation and lower amounts of nitrogen fixed. Early stages of the Bradyrhizobium japonicum–soybean [Glycine max (L.) Merr.] symbiosis, such as excretion of genistein (the plant-to-bacteria signal) and infection initiation can be inhibited by abiotic stresses; however, the effect on early events modulated by Nod Factors (bacteria-to-plant signalling), particularly root hair deformations is unknown. Thus, the objective of this study was to evaluate the perception of Nod Factor by soybean root hairs under three stress conditions: low temperature, low pH, and high salinity. Three experiments were conducted using a 1:1 ratio of Nod Bj-V (C18:1, MeFuc) and Nod Bj-V (Ac, C16:0, MeFuc). Nod Factor induced four types of root hair deformation (HAD), wiggling, bulging, curling, and branching. Under optimal experimental conditions root hair response to the three levels of Nod Factor tested (10 26 ,1 0 28 , and 10 210 M) was dosedependent. The highest frequency of root hair deformations was elicited by the 10 26 M level. Root hair deformation decreased with temperature (25, 17, and 15 8C), low pH, and high salinity. Nod Factor concentration did not interact with either low temperature or pH. However, salinity strongly inhibited HAD responses to increases in Nod Factor concentration. Thus, the addition of higher levels of Nod Factor is able to overcome the effects of low pH and temperature stress, but not salinity.
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perception of bradyrhizobium japonicum Nod Factor by soybean glycine max l merr root hairs under abiotic stress conditions
Journal of Experimental Botany, 2004Co-Authors: Haifa M Duzan, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Suboptimal growth conditions, such as low rhizosphere temperature, high salinity, and low pH can negatively affect the rhizobia–legume symbioses, resulting in poor Nodulation and lower amounts of nitrogen fixed. Early stages of the Bradyrhizobium japonicum–soybean [Glycine max (L.) Merr.] symbiosis, such as excretion of genistein (the plant-to-bacteria signal) and infection initiation can be inhibited by abiotic stresses; however, the effect on early events modulated by Nod Factors (bacteria-to-plant signalling), particularly root hair deformations is unknown. Thus, the objective of this study was to evaluate the perception of Nod Factor by soybean root hairs under three stress conditions: low temperature, low pH, and high salinity. Three experiments were conducted using a 1:1 ratio of Nod Bj-V (C18:1, MeFuc) and Nod Bj-V (Ac, C16:0, MeFuc). Nod Factor induced four types of root hair deformation (HAD), wiggling, bulging, curling, and branching. Under optimal experimental conditions root hair response to the three levels of Nod Factor tested (10 26 ,1 0 28 , and 10 210 M) was dosedependent. The highest frequency of root hair deformations was elicited by the 10 26 M level. Root hair deformation decreased with temperature (25, 17, and 15 8C), low pH, and high salinity. Nod Factor concentration did not interact with either low temperature or pH. However, salinity strongly inhibited HAD responses to increases in Nod Factor concentration. Thus, the addition of higher levels of Nod Factor is able to overcome the effects of low pH and temperature stress, but not salinity.
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a host specific bacteria to plant signal molecule Nod Factor enhances germination and early growth of diverse crop plants
Planta, 2003Co-Authors: Balakrishnan Prithiviraj, Xiaomin Zhou, Alfred Souleimanov, W M Kahn, Donald L SmithAbstract:Lipo-chitooligosaccharides (LCOs), or Nod Factors, are host-specific bacteria-to-plant signal molecules essential for the establishment of a successful N2-fixing legume–rhizobia symbiosis. At submicromolar concentrations Nod Factors induce physiological changes in host and non-host plants. Here we show that the Nod Factor Nod Bj V(C18:1,MeFuc) of Bradyrhizobium japonicum 532C enhances germination of a variety of economically important plants belonging to diverse botanical families: Zea mays, Oryza sativa (Poaceae), Beta vulgaris (Chenopodaceae), Glycine max, Phaseolus vulgaris (Fabaceae), and Gossypium hirsutum (Malvaceae), under laboratory, greenhouse and field conditions. Similar increases in germination were observed for filtrates of genistein-induced cultures of B. japonicum 532C, while non-induced B. japonicum, induced Bj 168 (a NodC mutant of B. japonicum deficient in Nod Factor synthesis) or the pentamer of chitin did not invoke such responses, demonstrating the role of Nod Factor in the observed effects. In addition, three out of four synthetic LCOs evaluated also promoted germination of corn, soybean and Arabidopsis thaliana seeds. LCO also enhanced the early growth of corn seedlings under greenhouse conditions. These findings suggest the possible use of LCOs for improved crop production.
Ton Bisseling - One of the best experts on this subject based on the ideXlab platform.
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Nod Factor Receptors Form Heteromeric Complexes and Are Essential for Intracellular Infection in Medicago Nodules
The Plant Cell, 2014Co-Authors: Sjef Moling, Erik Limpens, Anna Pietraszewska-bogiel, Marten Postma, Elena Fedorova, Mark A. Hink, Theodorus W. J. Gadella, Ton BisselingAbstract:Rhizobial Nod Factors are the key signaling molecules in the legume-rhizobium Nodule symbiosis. In this study, the role of the Nod Factor receptors Nod Factor PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root Nodules was investigated. It was found that inside Medicago truncatula Nodules, NFP and LYK3 localize at the cell periphery in a narrow zone of about two cell layers at the Nodule apex. This restricted accumulation is narrower than the region of promoter activity/mRNA accumulation and might serve to prevent the induction of defense-like responses and/or to restrict the rhizobium release to precise cell layers. The distal cell layer where the receptors accumulate at the cell periphery is part of the meristem, and the proximal layer is part of the infection zone. In these layers, the receptors can most likely perceive the bacterial Nod Factors to regulate the formation of symbiotic interface. Furthermore, our Forster resonance energy transfer-fluorescence lifetime imaging microscopy analysis indicates that NFP and LYK3 form heteromeric complexes at the cell periphery in M. truncatula Nodules.
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Evolutionary origin of rhizobium Nod Factor signaling.
Plant Signaling & Behavior, 2011Co-Authors: Arend Streng, Ton Bisseling, Rik Op Den Camp, René GeurtsAbstract:For over two decades now, it is known that the Nodule symbiosis between legume plants and nitrogen fixing rhizobium bacteria is set in motion by the bacterial signal molecule named Nodulation (Nod) Factor.1 Upon Nod Factor perception a signaling cascade is activated that is also essential for endomycorrhizal symbiosis (Fig. 1). This suggests that rhizobium co-opted the evolutionary far more ancient mycorrhizal signaling pathway in order to establish an endosymbiotic interaction with legumes.2 As arbuscular mycorrhizal fungi of the Glomeromycota phylum can establish a symbiosis with the fast majority of land plants, it is most probable that this signaling cascade is wide spread in plant kingdom.3 However, Nod Factor perception generally is considered to be unique to legumes. Two recent breakthroughs on the evolutionary origin of Rhizobium Nod Factor signaling demonstrate that this is not the case.4,5 The purification of Nod Factor-like molecules excreted by the mycorrhizal fungus Glomus intraradices and th...
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medicago lyk3 an entry receptor in rhizobial Nodulation Factor signaling
Plant Physiology, 2007Co-Authors: Patrick Smit, Clare Gough, René Geurts, Erik Limpens, Elena Fedorova, Elena A Dolgikh, Ton BisselingAbstract:Rhizobia secrete Nodulation (Nod) Factors, which set in motion the formation of nitrogen-fixing root Nodules on legume host plants. Nod Factors induce several cellular responses in root hair cells within minutes, but also are essential for the formation of infection threads by which rhizobia enter the root. Based on studies using bacterial mutants, a two-receptor model was proposed, a signaling receptor that induces early responses with low requirements toward Nod Factor structure and an entry receptor that controls infection with more stringent demands. Recently, putative Nod Factor receptors were shown to be LysM domain receptor kinases. However, mutants in these receptors, in both Lotus japonicus (nfr1 and nfr5) and Medicago truncatula (Medicago; nfp), do not support the two-receptor model because they lack all Nod Factor-induced responses. LYK3, the putative Medicago ortholog of NFR1, has only been studied by RNA interference, showing a role in infection thread formation. Medicago hair curling (hcl) mutants are unable to form curled root hairs, a step preceding infection thread formation. We identified the weak hcl-4 allele that is blocked during infection thread growth. We show that HCL encodes LYK3 and, thus, that this receptor, besides infection, also controls root hair curling. By using rhizobial mutants, we also show that HCL controls infection thread formation in a Nod Factor structure-dependent manner. Therefore, LYK3 functions as the proposed entry receptor, specifically controlling infection. Finally, we show that LYK3, which regulates a subset of Nod Factor-induced genes, is not required for the induction of NodULE INCEPTION.
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Nod Factor signaling genes and their function in the early stages of rhizobium infection
Current Opinion in Plant Biology, 2005Co-Authors: René Geurts, Elena Fedorova, Ton BisselingAbstract:A lipochitosaccharide-based signal molecule that is secreted by Rhizobium, named Nod Factor (NF), induces root Nodule formation in legumes. This molecule is also essential for the establishment of bacterial infection. Genetic analyses in the legume species Lotus japonicus and Medicago truncatula have led to the identification of many components of the NF signaling cascade. At least three of these genes do not function exclusively in the Rhizobium symbiosis but are also essential for the formation of mycorrhiza, an endosymbiosis found in many higher plant species. Recent studies have advanced our understanding of the functions of NF signaling genes in the Rhizobium infection process and the extent to which these genes are unique to legumes.
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nsp1 of the gras protein family is essential for rhizobial Nod Factor induced transcription
Science, 2005Co-Authors: Patrick Smit, Ton Bisseling, John Raedts, Vladimir Portyanko, Frederic Debelle, René GeurtsAbstract:Rhizobial Nod Factors induce in their legume hosts the expression of many genes and set in motion developmental processes leading to root Nodule formation. Here we report the identification of the Medicago GRAS-type protein Nodulation signaling pathway 1 (NSP1), which is essential for all known Nod Factor-induced changes in gene expression. NSP1 is constitutively expressed, and so it acts as a primary transcriptional regulator mediating all known Nod Factor-induced transcriptional responses, and therefore, we named it a Nod Factor response Factor.
Jens Stougaard - One of the best experts on this subject based on the ideXlab platform.
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Dynamics of ethylene production in response to compatible Nod Factor
Plant Physiology, 2018Co-Authors: Dugald Reid, Huijun Liu, Simon Kelly, Yasuyuki Kawaharada, Terry Mun, Stig U. Andersen, Guilhem Desbrosses, Jens StougaardAbstract:Establishment of symbiotic nitrogen-fixation in legumes is regulated by the plant hormone ethylene, but it has remained unclear whether and how its biosynthesis is regulated by the symbiotic pathway. We established a sensitive ethylene detection system for Lotus japonicus and found that ethylene production increased as early as 6 hours after inoculation with Mesorhizobium loti. This ethylene response was dependent on Nod Factor production by compatible rhizobia. Analyses of Nodulation mutants showed that perception of Nod Factor was required for ethylene emission, while downstream transcription Factors including CYCLOPS, NIN, and ERN1 were not required for this response. Activation of the Nodulation signaling pathway in spontaneously Nodulating mutants was also sufficient to elevate ethylene production. Ethylene signaling is controlled by EIN2, which is duplicated in L. japonicus. We obtained a L. japonicus Ljein2a Ljein2b double mutant that exhibits complete ethylene insensitivity and confirms that these two genes act redundantly in ethylene signaling. Consistent with this redundancy, both LjEin2a and LjEin2b are required for negative regulation of Nodulation and Ljein2a Ljein2b double mutants are hyperNodulating and hyperinfected. We also identified an unexpected role for ethylene in the onset of nitrogen fixation, with the Ljein2a Ljein2b double mutant showing severely reduced nitrogen fixation. These results demonstrate that ethylene production is an early and sustained Nodulation response that acts at multiple stages to regulate infection, Nodule organogenesis, and nitrogen fixation in L. japonicus.
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regulation of Nod Factor biosynthesis by alternative Nodd proteins at distinct stages of symbiosis provides additional compatibility scrutiny
Environmental Microbiology, 2018Co-Authors: Simon Kelly, Simona Radutoiu, Yasuyuki Kawaharada, John T Sullivan, Clive W Ronson, Jens StougaardAbstract:The Lotus japonicus symbiont Mesorhizobium loti R7A encodes two copies of NodD and here we identify striking differences in Nod Factor biosynthesis gene induction by NodD1 and NodD2 both in vitro and in planta. We demonstrate that induction of Nod Factor biosynthesis genes is preferentially controlled by NodD1 and NodD2 at specific stages of symbiotic infection. NodD2 is primarily responsible for induction in the rhizosphere and within Nodules, while NodD1 is primarily responsible for induction within root hair infection threads. NodD1 and NodD2 mutants showed significant symbiotic phenotypes and competition studies establish that NodD1 and NodD2 mutants were severely outcompeted by wild-type R7A, indicating that both proteins are required for proficient symbiotic infection. These results suggest preferential activation of NodD1 and NodD2 by different inducing compounds produced at defined stages of symbiotic infection. We identified Lotus chalcone isomerase CHI4 as a root hair induced candidate involved in the biosynthesis of an inducer compound that may be preferentially recognized by NodD1 within root hair infection threads. We propose an alternative explanation for the function of multiple copies of NodD that provides the host plant with another level of compatibility scrutiny at the stage of infection thread development.
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sinorhizobium fredii hh103 invades lotus burttii by crack entry in a Nod Factor and surface polysaccharide dependent manner
Molecular Plant-microbe Interactions, 2016Co-Authors: Niels Sandal, Yasuyuki Kawaharada, Sebastian Acostajurado, D N Rodrigueznavarro, Juan Fernandez Perea, Antonio M Gilserrano, Haojie Jin, Miguel A Rodriguezcarvajal, Stig Uggerhoj Andersen, Jens StougaardAbstract:Sinorhizobium fredii HH103-Rifr, a broad host range rhizobial strain, induces nitrogen-fixing Nodules in Lotus burttii but ineffective Nodules in L. japonicus. Confocal microscopy studies showed that Mesorhizobium loti MAFF303099 and S. fredii HH103-Rifr invade L. burttii roots through infection threads or epidermal cracks, respectively. Infection threads in root hairs were not observed in L. burttii plants inoculated with S. fredii HH103-Rifr. A S. fredii HH103-Rifr NodA mutant failed to Nodulate L. burttii, demonstrating that Nod Factors are strictly necessary for this crack-entry mode, and a noeL mutant was also severely impaired in L. burttii Nodulation, indicating that the presence of fucosyl residues in the Nod Factor is symbiotically relevant. However, significant symbiotic impacts due to the absence of methylation or to acetylation of the fucosyl residue were not detected. In contrast S. fredii HH103-Rifr mutants showing lipopolysaccharide alterations had reduced symbiotic capacity, while mutants ...
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sinorhizobium fredii hh103 invades lotus burttii by crack entry in a Nod Factor and surface polysaccharide dependent manner
Molecular Plant-microbe Interactions, 2016Co-Authors: Sebastian Acostajurado, Niels Sandal, Yasuyuki Kawaharada, Stig U. Andersen, D N Rodrigueznavarro, Juan Fernandez Perea, Antonio M Gilserrano, Haojie Jin, Miguel A Rodriguezcarvajal, Jens StougaardAbstract:Sinorhizobium fredii HH103-Rifr, a broad host range rhizobial strain, induces nitrogen-fixing Nodules in Lotus burttii but ineffective Nodules in L. japonicus. Confocal microscopy studies showed that Mesorhizobium loti MAFF303099 and S. fredii HH103-Rifr invade L. burttii roots through infection threads or epidermal cracks, respectively. Infection threads in root hairs were not observed in L. burttii plants inoculated with S. fredii HH103-Rifr. A S. fredii HH103-Rifr NodA mutant failed to Nodulate L. burttii, demonstrating that Nod Factors are strictly necessary for this crack-entry mode, and a noeL mutant was also severely impaired in L. burttii Nodulation, indicating that the presence of fucosyl residues in the Nod Factor is symbiotically relevant. However, significant symbiotic impacts due to the absence of methylation or to acetylation of the fucosyl residue were not detected. In contrast S. fredii HH103-Rifr mutants showing lipopolysaccharide alterations had reduced symbiotic capacity, while mutants affected in production of either exopolysaccharides, capsular polysaccharides, or both were not impaired in Nodulation. Mutants unable to produce cyclic glucans and purine or pyrimidine auxotrophic mutants formed ineffective Nodules with L. burttii. Flagellin-dependent bacterial mobility was not required for crack infection, since HH103-Rifr fla mutants Nodulated L. burttii. None of the S. fredii HH103-Rifr surface-polysaccharide mutants gained effective Nodulation with L. japonicus.
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Autophosphorylation is essential for the in vivo function of the Lotus japonicus Nod Factor receptor 1 and receptor-mediated signalling in cooperation with Nod Factor receptor 5
The Plant Journal, 2010Co-Authors: Esben Bjørn Madsen, Meritxell Antolín-llovera, Christina Grossmann, Syndi Vieweg, Angelique Broghammer, Lene Krusell, Simona Radutoiu, Ole Nørregaard Jensen, Jens StougaardAbstract:Soil-living rhizobia secrete lipochitin oligosaccharides known as Nod Factors, which in Lotus japonicus are perceived by at least two Nod-Factor receptors, NFR1 and NFR5. Despite progress in identifying molecular components critical for initial legume host recognition of the microsymbiont and cloning of downstream components, little is known about the activation and signalling mechanisms of the Nod-Factor receptors themselves. Here we show that both receptor proteins localize to the plasma membrane, and present evidence for heterocomplex formation initiating downstream signalling. Expression of NFR1 and NFR5 in Nicotiana benthamiana and Allium ampeloprasum (leek) cells caused a rapid cell-death response. The signalling leading to cell death was abrogated using a kinase-inactive variant of NFR1. In these surviving cells, a clear interaction between NFR1 and NFR5 was detected in vivo through bimolecular fluorescence complementation (BiFC). To analyse the inter- and intramolecular phosphorylation events of the kinase complex, the cytoplasmic part of NFR1 was assayed for in vitro kinase activity, and autophosphorylation on 24 amino acid residues, including three tyrosine residues, was found by mass spectrometry. Substitution of the phosphorylated amino acids of NFR1 identified a single phosphorylation site to be essential for NFR1 Nod-Factor signalling in vivo and kinase activity in vitro. In contrast to NFR1, no in vitro kinase activity of the cytoplasmic domain of NFR5 was detected. This is further supported by the fact that a mutagenized NFR5 construct, substituting an amino acid essential for ATP binding, restored Nodulation of nfr5 mutant roots.
Alfred Souleimanov - One of the best experts on this subject based on the ideXlab platform.
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jasmonates induce Nod Factor production by bradyrhizobium japonicum
Plant Physiology and Biochemistry, 2006Co-Authors: Fazli Mabood, Alfred Souleimanov, Wajahatullah Khan, D L SmithAbstract:Jasmonates are signaling molecules involved in induced systemic resistance, wounding and stress responses of plants. We have previously demonstrated that jasmonates can induce Nod genes of Bradyrhizobium japonicum when measured by beta-galactosidase activity. In order to test whether jasmonates can effectively induce the production and secretion of Nod Factors (lipo-chitooligosaccharides, LCOs) from B. japonicum, we induced two B. japonicum strains, 532C and USDA3, with jasmonic acid (JA), methyl jasmonate (MeJA) and genistein (Ge). As genistein is well characterized as an inducer of Nod genes it was used a positive control. The high-performance liquid chromatography (HPLC) profile of LCOs isolated following treatment with jasmonates or genistein showed that both JA and MeJA effectively induced Nod genes and caused production of LCOs from bacterial cultures. JA and MeJA are more efficacious inducers of LCO production than genistein. Genistein plus JA or MeJA resulted in greater LCO production than either alone. A soybean root hair deformation assay showed that jasmonate induced LCOs were as effective as those induced by genistein. This is the first report that jasmonates induce Nod Factor production by B. japonicum. This report establishes the role of jasmonates as a new class of signaling molecules in the Bradyrhizobium-soybean symbiosis.
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jasmonates induce Nod Factor production by bradyrhizobium japonicum
Plant Physiology and Biochemistry, 2006Co-Authors: Fazli Mabood, Alfred Souleimanov, Wajahatullah Khan, D L SmithAbstract:Abstract Jasmonates are signaling molecules involved in induced systemic resistance, wounding and stress responses of plants. We have previously demonstrated that jasmonates can induce Nod genes of Bradyrhizobium japonicum when measured by β-galactosidase activity. In order to test whether jasmonates can effectively induce the production and secretion of Nod Factors (lipo-chitooligosaccharides, LCOs) from B. japonicum, we induced two B. japonicum strains, 532C and USDA3, with jasmonic acid (JA), methyl jasmonate (MeJA) and genistein (Ge). As genistein is well characterized as an inducer of Nod genes it was used a positive control. The high-performance liquid chromatography (HPLC) profile of LCOs isolated following treatment with jasmonates or genistein showed that both JA and MeJA effectively induced Nod genes and caused production of LCOs from bacterial cultures. JA and MeJA are more efficacious inducers of LCO production than genistein. Genistein plus JA or MeJA resulted in greater LCO production than either alone. A soybean root hair deformation assay showed that jasmonate induced LCOs were as effective as those induced by genistein. This is the first report that jasmonates induce Nod Factor production by B. japonicum. This report establishes the role of jasmonates as a new class of signaling molecules in the Bradyrhizobium–soybean symbiosis.
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Nod Factor induces soybean resistance to powdery mildew.
Plant Physiology and Biochemistry, 2005Co-Authors: Haifa M Duzan, Fazli Mabood, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Plants possess highly sensitive perception systems by which microbial signal molecules are recognized. In the Bradyrhizobium-soybean (Glycine max (L.) Merr.) symbiosis, recognition is initiated through exchange of signal molecules, generally flavonoids from soybean and lipo-chitooligosaccharides (Nod Factors) from the microsymbiont. Application of the Nod Factor Nod Bj-V (C18:1, MeFuc) induced soybean resistance to powdery mildew caused by Microsphaera diffusa. Addition of Nod Factor (concentrations ranging from 10(-6) to 10(-10) M) to soybean root systems led to reductions in disease incidence. The lowest disease incidence was caused by Nod Factor treatment at 10(-6) M. The effect of Nod Factor application on fungal growth and development was measured at 4, 12, 48, and 96 h after inoculation. Colony diameter and number of germ tubes per conidium were decreased by 10(-6) M Nod Factor. Phenylalanine ammonia lyase (PAL, EC.4.3.1.1.) is the first enzyme of the phenyl propanoid pathway, and is commonly activated as part of plant responses to disease. Treatment of soybean seedlings with Nod Factor, through stem wounds, induced PAL activity; the most rapid increase followed treatment with 10(-6) M Nod Factor. These data show that soybean plants are able to detect root applied LCO and respond by increased disease resistance.
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perception of bradyrhizobium japonicum Nod Factor by soybean glycine max l merr root hairs under abiotic stress conditions
Journal of Experimental Botany, 2004Co-Authors: Haifa M Duzan, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Suboptimal growth conditions, such as low rhizosphere temperature, high salinity, and low pH can negatively affect the rhizobia–legume symbioses, resulting in poor Nodulation and lower amounts of nitrogen fixed. Early stages of the Bradyrhizobium japonicum–soybean [Glycine max (L.) Merr.] symbiosis, such as excretion of genistein (the plant-to-bacteria signal) and infection initiation can be inhibited by abiotic stresses; however, the effect on early events modulated by Nod Factors (bacteria-to-plant signalling), particularly root hair deformations is unknown. Thus, the objective of this study was to evaluate the perception of Nod Factor by soybean root hairs under three stress conditions: low temperature, low pH, and high salinity. Three experiments were conducted using a 1:1 ratio of Nod Bj-V (C18:1, MeFuc) and Nod Bj-V (Ac, C16:0, MeFuc). Nod Factor induced four types of root hair deformation (HAD), wiggling, bulging, curling, and branching. Under optimal experimental conditions root hair response to the three levels of Nod Factor tested (10 26 ,1 0 28 , and 10 210 M) was dosedependent. The highest frequency of root hair deformations was elicited by the 10 26 M level. Root hair deformation decreased with temperature (25, 17, and 15 8C), low pH, and high salinity. Nod Factor concentration did not interact with either low temperature or pH. However, salinity strongly inhibited HAD responses to increases in Nod Factor concentration. Thus, the addition of higher levels of Nod Factor is able to overcome the effects of low pH and temperature stress, but not salinity.
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perception of bradyrhizobium japonicum Nod Factor by soybean glycine max l merr root hairs under abiotic stress conditions
Journal of Experimental Botany, 2004Co-Authors: Haifa M Duzan, Xiaomin Zhou, Alfred Souleimanov, Donald L SmithAbstract:Suboptimal growth conditions, such as low rhizosphere temperature, high salinity, and low pH can negatively affect the rhizobia–legume symbioses, resulting in poor Nodulation and lower amounts of nitrogen fixed. Early stages of the Bradyrhizobium japonicum–soybean [Glycine max (L.) Merr.] symbiosis, such as excretion of genistein (the plant-to-bacteria signal) and infection initiation can be inhibited by abiotic stresses; however, the effect on early events modulated by Nod Factors (bacteria-to-plant signalling), particularly root hair deformations is unknown. Thus, the objective of this study was to evaluate the perception of Nod Factor by soybean root hairs under three stress conditions: low temperature, low pH, and high salinity. Three experiments were conducted using a 1:1 ratio of Nod Bj-V (C18:1, MeFuc) and Nod Bj-V (Ac, C16:0, MeFuc). Nod Factor induced four types of root hair deformation (HAD), wiggling, bulging, curling, and branching. Under optimal experimental conditions root hair response to the three levels of Nod Factor tested (10 26 ,1 0 28 , and 10 210 M) was dosedependent. The highest frequency of root hair deformations was elicited by the 10 26 M level. Root hair deformation decreased with temperature (25, 17, and 15 8C), low pH, and high salinity. Nod Factor concentration did not interact with either low temperature or pH. However, salinity strongly inhibited HAD responses to increases in Nod Factor concentration. Thus, the addition of higher levels of Nod Factor is able to overcome the effects of low pH and temperature stress, but not salinity.