The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
Brett J Ferguson - One of the best experts on this subject based on the ideXlab platform.
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Systemic Regulation of Soybean Nodulation by Acidic Growth Conditions
Plant physiology, 2012Co-Authors: Meng-han Lin, Peter M Gresshoff, Brett J FergusonAbstract:Mechanisms inhibiting legume Nodulation by low soil pH, although highly prevalent and economically significant, are poorly understood. We addressed this in soybean (Glycine max) using a combination of physiological and genetic approaches. Split-root and grafting studies using an autoregulation-of-Nodulation-deficient mutant line, altered in the autoregulation-of-Nodulation receptor kinase GmNARK, determined that a systemic, shoot-controlled, and GmNARK-dependent mechanism was critical for facilitating the inhibitory effect. Acid inhibition was independent of aluminum ion concentration and occurred early in nodule development, between 12 and 96 h post inoculation with Bradyrhizobium japonicum. Biological effects were confirmed by measuring transcript numbers of known early Nodulation genes. Transcripts decreased on both sides of split-root systems, where only one side was subjected to low-pH conditions. Our findings enhance the present understanding of the innate mechanisms regulating legume Nodulation control under acidic conditions, which could benefit future attempts in agriculture to improve nodule development and biological nitrogen fixation in acid-stressed soils.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Plant Biotechnology Journal, 2012Co-Authors: Dugald Reid, Brett J Ferguson, Peter M Gresshoff, Satomi Hayashi, Michal T Lorenc, Jiri Stiller, David EdwardsAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean (Glycine max) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium-produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant (nodC-) strain of Bradyrhizobium japonicum. Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-beta-glucanase, a cytochrome P450 and a TIR-LRR-NBS receptor kinase, was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Centre for Tropical Crops and Biocommodities; Science & Engineering Faculty, 2012Co-Authors: Satomi Hayashi, Dugald Reid, Peter M Gresshoff, Michal T Lorenc, Jiri Stiller, David Edwards, Brett J FergusonAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean ( Glycine max ) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium -produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant ( nodC - ) strain of Bradyrhizobium japonicum . Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-β-glucanase , a cytochrome P450 and a TIR-LRR-NBS receptor kinase , was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation
Peter M Gresshoff - One of the best experts on this subject based on the ideXlab platform.
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Systemic Regulation of Soybean Nodulation by Acidic Growth Conditions
Plant physiology, 2012Co-Authors: Meng-han Lin, Peter M Gresshoff, Brett J FergusonAbstract:Mechanisms inhibiting legume Nodulation by low soil pH, although highly prevalent and economically significant, are poorly understood. We addressed this in soybean (Glycine max) using a combination of physiological and genetic approaches. Split-root and grafting studies using an autoregulation-of-Nodulation-deficient mutant line, altered in the autoregulation-of-Nodulation receptor kinase GmNARK, determined that a systemic, shoot-controlled, and GmNARK-dependent mechanism was critical for facilitating the inhibitory effect. Acid inhibition was independent of aluminum ion concentration and occurred early in nodule development, between 12 and 96 h post inoculation with Bradyrhizobium japonicum. Biological effects were confirmed by measuring transcript numbers of known early Nodulation genes. Transcripts decreased on both sides of split-root systems, where only one side was subjected to low-pH conditions. Our findings enhance the present understanding of the innate mechanisms regulating legume Nodulation control under acidic conditions, which could benefit future attempts in agriculture to improve nodule development and biological nitrogen fixation in acid-stressed soils.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Plant Biotechnology Journal, 2012Co-Authors: Dugald Reid, Brett J Ferguson, Peter M Gresshoff, Satomi Hayashi, Michal T Lorenc, Jiri Stiller, David EdwardsAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean (Glycine max) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium-produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant (nodC-) strain of Bradyrhizobium japonicum. Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-beta-glucanase, a cytochrome P450 and a TIR-LRR-NBS receptor kinase, was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Centre for Tropical Crops and Biocommodities; Science & Engineering Faculty, 2012Co-Authors: Satomi Hayashi, Dugald Reid, Peter M Gresshoff, Michal T Lorenc, Jiri Stiller, David Edwards, Brett J FergusonAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean ( Glycine max ) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium -produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant ( nodC - ) strain of Bradyrhizobium japonicum . Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-β-glucanase , a cytochrome P450 and a TIR-LRR-NBS receptor kinase , was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation
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plant genetic control of Nodulation
Annual Review of Microbiology, 1991Co-Authors: Gustavo Caetanoanolles, Peter M GresshoffAbstract:INTRODUCTION 345 LEGUME Nodulation . . ........ ....... ... .. ... . . ....... ..... ........ . 346 ROLE OF THE BACTERIAL SYMBIONT: SIGNAL EXCHANGE 348 Nodulation AS A DEVELOPMENTALLY REGULATED PHENOMENON....... 354 PLANT Nodulation MUTANTS 357 Nodulation CONTROL IN LEGUMES 361 AUTOREGULATION ...... ........ 362 What Is the Signal Transduction Mechanism? an Example of Systemic Root-Shoot Interaction .... .. . .. .... .. ....... ""'''''''''''''''''''''''''' .. " .. ,," 363 How Is Nodulation Suppressed? " 364 What Triggers the Systemic Response?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365 A Working Hypothesis. . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . ..... . . . . . . . . . . . . . ... .. . 367 Nodulation IN THE ABSENCE OF RHIZOBIUM SPP. 368 PERSPECTIVES 370
Satomi Hayashi - One of the best experts on this subject based on the ideXlab platform.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Plant Biotechnology Journal, 2012Co-Authors: Dugald Reid, Brett J Ferguson, Peter M Gresshoff, Satomi Hayashi, Michal T Lorenc, Jiri Stiller, David EdwardsAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean (Glycine max) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium-produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant (nodC-) strain of Bradyrhizobium japonicum. Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-beta-glucanase, a cytochrome P450 and a TIR-LRR-NBS receptor kinase, was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation.
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transient nod factor dependent gene expression in the Nodulation competent zone of soybean glycine max l merr roots
Centre for Tropical Crops and Biocommodities; Science & Engineering Faculty, 2012Co-Authors: Satomi Hayashi, Dugald Reid, Peter M Gresshoff, Michal T Lorenc, Jiri Stiller, David Edwards, Brett J FergusonAbstract:All lateral organ development in plants, such as Nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. A total mRNA profiling approach using RNA-seq to target the specific soybean ( Glycine max ) root tissues responding to compatible rhizobia [i.e. the Zone Of Nodulation (ZON)] revealed a large number of novel, often transient, mRNA changes occurring during the early stages of Nodulation. Focusing on the ZON enabled us to discard the majority of root tissues and their developmentally diverse gene transcripts, thereby highlighting the lowly and transiently expressed Nodulation-specific genes. It also enabled us to concentrate on a precise moment in early nodule development at each sampling time. We focused on discovering genes regulated specifically by the Bradyrhizobium -produced Nod factor signal, by inoculating roots with either a competent wild-type or incompetent mutant ( nodC - ) strain of Bradyrhizobium japonicum . Collectively, 2915 genes were identified as being differentially expressed, including many known soybean Nodulation genes. A number of unknown Nodulation gene candidates and soybean orthologues of Nodulation genes previously reported in other legume species were also identified. The differential expression of several candidates was confirmed and further characterized via inoculation time-course studies and qRT-PCR. The expression of many genes, including an endo-1,4-β-glucanase , a cytochrome P450 and a TIR-LRR-NBS receptor kinase , was transient, peaking quickly during the initiation of nodule ontogeny. Additional genes were found to be down-regulated. Significantly, a set of differentially regulated genes acting in the gibberellic acid (GA) biosynthesis pathway was discovered, suggesting a novel role of GAs in Nodulation
Priyanka Singla - One of the best experts on this subject based on the ideXlab platform.
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Stimulation of nitrogen fixation and trehalose biosynthesis by naringenin (Nar) and arbuscular mycorrhiza (AM) in chickpea under salinity stress
Plant Growth Regulation, 2016Co-Authors: Neera Garg, Priyanka SinglaAbstract:Legumes are extremely susceptible to soil salinity because of high sensitivity of nitrogen‐fixing nodules, where root hair infection and Nodulation are particularly salt sensitive. Arbuscular mycorrhiza (AM) inoculation is a promising approach to improve rhizobial symbiosis and hence growth. Flavonoids such as naringenin (Nar), play an imperative role in tripartite symbiosis of rhizobia and AM with legumes by signalling both symbioses. Modulation in flavonoids content is one of the important factors limiting Nodulation and mycorrhization in salt stressed plants. Green house study investigated the potential of Nar (4 µM) and mycorrhiza ( Funneliformis mosseae ) in enhancing Nodulation and nitrogen fixation in Cicer arietinum L. genotypes (PBG 5, DCP 92-3) under NaCl (0–100 mM). High sodium concentration in the nodules deleteriously affected Nodulation, rate of nitrogen fixation, endogenous Nar and nutrient status, with higher negative effects in DCP 92-3 than PBG 5, which could be directly correlated with higher mycorrhizal dependency and lower colonization. Exogenous Nar partly restored Nodulation and mycorrhization indicating its involvement as signal molecule in symbiosis. Mycorrhization and Nar enhanced salt induced trehalose 6-P-synthase and phosphatase and reduced trehalase activity, ensuing higher trehalose biosynthesis in nodules. Relative assessment of AM and Nar indicated a more prominent contribution of AM in reducing Na^+ uptake and improving phosphorus, with Nodulation and trehalose synthesis exhibiting higher dependency on Nar. Complete amelioration of negative effects of salinity were observed with +Nar+AM, thereby suggesting complementation of Nar and AM in improving symbiotic efficiency of chickpea under salt stress.
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Stimulation of nitrogen fixation and trehalose biosynthesis by naringenin (Nar) and arbuscular mycorrhiza (AM) in chickpea under salinity stress
Plant Growth Regulation, 2016Co-Authors: Neera Garg, Priyanka SinglaAbstract:Legumes are extremely susceptible to soil salinity because of high sensitivity of nitrogen‐fixing nodules, where root hair infection and Nodulation are particularly salt sensitive. Arbuscular mycorrhiza (AM) inoculation is a promising approach to improve rhizobial symbiosis and hence growth. Flavonoids such as naringenin (Nar), play an imperative role in tripartite symbiosis of rhizobia and AM with legumes by signalling both symbioses. Modulation in flavonoids content is one of the important factors limiting Nodulation and mycorrhization in salt stressed plants. Green house study investigated the potential of Nar (4 µM) and mycorrhiza ( Funneliformis mosseae ) in enhancing Nodulation and nitrogen fixation in Cicer arietinum L. genotypes (PBG 5, DCP 92-3) under NaCl (0–100 mM). High sodium concentration in the nodules deleteriously affected Nodulation, rate of nitrogen fixation, endogenous Nar and nutrient status, with higher negative effects in DCP 92-3 than PBG 5, which could be directly correlated with higher mycorrhizal dependency and lower colonization. Exogenous Nar partly restored Nodulation and mycorrhization indicating its involvement as signal molecule in symbiosis. Mycorrhization and Nar enhanced salt induced trehalose 6-P-synthase and phosphatase and reduced trehalase activity, ensuing higher trehalose biosynthesis in nodules. Relative assessment of AM and Nar indicated a more prominent contribution of AM in reducing Na^+ uptake and improving phosphorus, with Nodulation and trehalose synthesis exhibiting higher dependency on Nar. Complete amelioration of negative effects of salinity were observed with +Nar+AM, thereby suggesting complementation of Nar and AM in improving symbiotic efficiency of chickpea under salt stress.
Marion Cerri - One of the best experts on this subject based on the ideXlab platform.
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NIN Acts as a Network Hub Controlling a Growth Module Required for Rhizobial Infection
Plant Physiology, 2019Co-Authors: Cheng-wu Liu, Andrew Breakspear, Dian Guan, Marion Cerri, Kirsty Jackson, Suyu Jiang, Fran Robson, Guru Radhakrishnan, Sonali Roy, Caitlin BoneAbstract:The symbiotic infection of root cells by nitrogen-fixing rhizobia during Nodulation requires the transcription factor Nodule Inception (NIN). Our root hair transcriptomic study extends NIN's regulon to include Rhizobium Polar Growth and genes involved in cell wall modification, gibberellin biosynthesis, and a comprehensive group of nutrient (N, P, and S) uptake and assimilation genes, suggesting that NIN's recruitment to Nodulation was based on its role as a growth module, a role shared with other NIN-Like Proteins. The expression of jasmonic acid genes in nin suggests the involvement of NIN in the resolution of growth versus defense outcomes. We find that the regulation of the growth module component Nodulation Pectate Lyase by NIN, and its function in rhizobial infection, are conserved in hologalegina legumes, highlighting its recruitment as a major event in the evolution of Nodulation. We find that Nodulation Pectate Lyase is secreted to the infection chamber and the lumen of the infection thread. Gene network analysis using the transcription factor mutants for ERF Required for Nodulationl and Nuclear Factor-Y Subunit Al confirms hierarchical control of NIN over Nuclear Factor-Y Subunit Al and shows that ERF Required for Nodulationl acts independently to control infection. We conclude that while NIN shares functions with other NIN-Like Proteins, the conscription of key infection genes to NIN's control has made it a central regulatory hub for rhizobial infection.
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The Symbiosis-Related ERN Transcription Factors Act in Concert to Coordinate Rhizobial Host Root Infection
Plant Physiology, 2016Co-Authors: Marion Cerri, Lisa Frances, Marie-christine Auriac, Joëlle Fournier, Audrey Kelner, Patrick Middleton, Kirankumar Mysore, Jiangqi Wen, Monique Erard, David BarkerAbstract:Legumes improve their mineral nutrition through nitrogen-fixing root nodule symbioses with soil rhizobia. Rhizobial infection of legumes is regulated by a number of transcription factors, including ERF Required for Nodulation1 (ERN1). Medicago truncatula plants defective in ERN1 are unable to nodulate, but still exhibit early symbiotic responses including rhizobial infection. ERN1 has a close homolog, ERN2, which shows partially overlapping expression patterns. Here we show that ern2 mutants exhibit a later Nodulation phenotype than ern1, being able to form nodules but with signs of premature senescence. Molecular characterization of the ern2-1 mutation reveals a key role for a conserved threonine for both DNA binding and transcriptional activity. In contrast to either single mutant, the double ern1-1 ern2-1 line is completely unable to initiate infection or nodule development. The strong ern1-1 ern2-1 phenotype demonstrates functional redundancy between these two transcriptional regulators and reveals the essential role of ERN1/ERN2 to coordinately induce rhizobial infection and nodule organogenesis. While ERN1/ERN2 act in concert in the root epidermis, only ERN1 can efficiently allow the development of mature nodules in the cortex, probably through an independent pathway. Together, these findings reveal the key roles that ERN1/ERN2 play at the very earliest stages of root nodule development.
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Medicago truncatula ERN Transcription Factors: Regulatory Interplay with NSP1/NSP2 GRAS Factors and Expression Dynamics throughout Rhizobial Infection
Plant Physiology, 2012Co-Authors: Marion Cerri, Lisa Frances, Tom Laloum, Marie-christine Auriac, Andréas Niebel, Giles E. D. Oldroyd, David Barker, Joëlle Fournier, Fernanda De Carvalho-niebelAbstract:Rhizobial Nodulation factors (NFs) activate a specific signaling pathway in Medicago truncatula root hairs that involves the complex interplay of Nodulation Signaling Pathway1 (NSP1)/NSP2 GRAS and Ethylene Response Factor Required for Nodulation1 (ERN1) transcription factors (TFs) to achieve full ENOD11 transcription. ERN1 acts as a direct transcriptional regulator of ENOD11 through the activation of the NF-responsive "NF box." Here, we show that NSP1, when combined with NSP2, can act as a strong positive regulator of ERN1 and ENOD11 transcription. Although ERN1 and NSP1/NSP2 both activate ENOD11, two separate promoter regions are involved that regulate expression during consecutive symbiotic stages. Our findings indicate that ERN1 is required to activate NF-elicited ENOD11 expression exclusively during early preinfection,while NSP1/NSP2 mediates ENOD11 expression during subsequent rhizobial-infection. The relative contributions of ERN1 and the closely related ERN2 to the rhizobial symbiosis were then evaluated by comparing their regulation and in vivo dynamics. ERN1 and ERN2 exhibit expression profiles compatible with roles during NF signaling and subsequent infection. However, differences in expression levels and spatiotemporal profiles suggest specialized functions for these two TFs, ERN1 being involved in stages preceding and accompanying infection thread progression while ERN2 is only involved in certain stages of infection. By cross complementation, we show that ERN2, when expressed under the control of the ERN1 promoter, can restore both NF-elicited ENOD11 expression and nodule formation in an ern1 mutant background. This indicates that ERN1 and ERN2 possess similar biological activities and that functional diversification of these closely related TFs relies primarily on changes in tissue-specific expression patterns.