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Habte N, Girma G, Xu X, Liao CJ, Adeyanju A, Hailemariam S, Lee S, Okoye P, Ejeta G, Mengiste T. Haplotypes at the sorghum ARG4 and ARG5 NLR loci confer resistance to anthracnose. Plant J 2024; 118:106-123. [PMID: 38111157 DOI: 10.1111/tpj.16594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 12/01/2023] [Accepted: 12/06/2023] [Indexed: 12/20/2023]
Abstract
Sorghum anthracnose caused by the fungus Colletotrichum sublineola (Cs) is a damaging disease of the crop. Here, we describe the identification of ANTHRACNOSE RESISTANCE GENES (ARG4 and ARG5) encoding canonical nucleotide-binding leucine-rich repeat (NLR) receptors. ARG4 and ARG5 are dominant resistance genes identified in the sorghum lines SAP135 and P9830, respectively, that show broad-spectrum resistance to Cs. Independent genetic studies using populations generated by crossing SAP135 and P9830 with TAM428, fine mapping using molecular markers, comparative genomics and gene expression studies determined that ARG4 and ARG5 are resistance genes against Cs strains. Interestingly, ARG4 and ARG5 are both located within clusters of duplicate NLR genes at linked loci separated by ~1 Mb genomic region. SAP135 and P9830 each carry only one of the ARG genes while having the recessive allele at the second locus. Only two copies of the ARG5 candidate genes were present in the resistant P9830 line while five non-functional copies were identified in the susceptible line. The resistant parents and their recombinant inbred lines carrying either ARG4 or ARG5 are resistant to strains Csgl1 and Csgrg suggesting that these genes have overlapping specificities. The role of ARG4 and ARG5 in resistance was validated through sorghum lines carrying independent recessive alleles that show increased susceptibility. ARG4 and ARG5 are located within complex loci displaying interesting haplotype structures and copy number variation that may have resulted from duplication. Overall, the identification of anthracnose resistance genes with unique haplotype stucture provides a foundation for genetic studies and resistance breeding.
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Affiliation(s)
- Nida Habte
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Gezahegn Girma
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Xiaochen Xu
- Department of Agronomy, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Adedayo Adeyanju
- Department of Agronomy, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Sara Hailemariam
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Pascal Okoye
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, Indiana, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, 47907, USA
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Li D, Song F, Mengiste T. Editorial: Molecular biology of plant-fungal interactions. Front Plant Sci 2024; 15:1392149. [PMID: 38504904 PMCID: PMC10949945 DOI: 10.3389/fpls.2024.1392149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 02/28/2024] [Indexed: 03/21/2024]
Affiliation(s)
- Dayong Li
- Ministry of Agriculture and Rural Affairs Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Fengming Song
- Ministry of Agriculture and Rural Affairs Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou, China
- State Key Laboratory for Rice Biology and Breeding, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
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Bi K, Liang Y, Mengiste T, Sharon A. Killing softly: a roadmap of Botrytis cinerea pathogenicity. Trends Plant Sci 2023; 28:211-222. [PMID: 36184487 DOI: 10.1016/j.tplants.2022.08.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 08/23/2022] [Accepted: 08/31/2022] [Indexed: 06/16/2023]
Abstract
Botrytis cinerea, a widespread plant pathogen with a necrotrophic lifestyle, causes gray mold disease in many crops. Massive secretion of enzymes and toxins was long considered to be the main driver of infection, but recent studies have uncovered a rich toolbox for B. cinerea pathogenicity. The emerging picture is of a multilayered infection process governed by the exchange of factors that collectively contribute to disease development. No plant shows complete resistance against B. cinerea, but pattern-triggered plant immune responses have the potential to significantly reduce disease progression, opening new possibilities for producing B. cinerea-tolerant plants. We examine current B. cinerea infection models, highlight knowledge gaps, and suggest directions for future studies.
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Affiliation(s)
- Kai Bi
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan City, Hubei Province, China
| | - Yong Liang
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, 915 West State Street, West Lafayette, IN 47907, USA
| | - Amir Sharon
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
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Mewa DB, Lee S, Liao C, Adeyanju A, Helm M, Lisch D, Mengiste T. ANTHRACNOSE RESISTANCE GENE2 confers fungal resistance in sorghum. Plant J 2023; 113:308-326. [PMID: 36441009 PMCID: PMC10108161 DOI: 10.1111/tpj.16048] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 11/16/2022] [Accepted: 11/22/2022] [Indexed: 06/16/2023]
Abstract
Sorghum is an important food and feed crop globally; its production is hampered by anthracnose disease caused by the fungal pathogen Colletotrichum sublineola (Cs). Here, we report identification and characterization of ANTHRACNOSE RESISTANCE GENE 2 (ARG2) encoding a nucleotide-binding leucine-rich repeat (NLR) protein that confers race-specific resistance to Cs strains. ARG2 is one of a cluster of several NLR genes initially identified in the sorghum differential line SC328C that is resistant to some Cs strains. This cluster shows structural and copy number variations in different sorghum genotypes. Different sorghum lines carrying independent ARG2 alleles provided the genetic validation for the identity of the ARG2 gene. ARG2 expression is induced by Cs, and chitin induces ARG2 expression in resistant but not in susceptible lines. ARG2-mediated resistance is accompanied by higher expression of defense and secondary metabolite genes at early stages of infection, and anthocyanin and zeatin metabolisms are upregulated in resistant plants. Interestingly, ARG2 localizes to the plasma membrane when transiently expressed in Nicotiana benthamiana. Importantly, ARG2 plants produced higher shoot dry matter than near-isogenic lines carrying the susceptible allele suggesting an absence of an ARG2 associated growth trade-off. Furthermore, ARG2-mediated resistance is stable at a wide range of temperatures. Our observations open avenues for resistance breeding and for dissecting mechanisms of resistance.
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Affiliation(s)
- Demeke B. Mewa
- Department of Botany and Plant Pathology, Purdue University915 W. State St.West LafayetteIN47907USA
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University915 W. State St.West LafayetteIN47907USA
| | - Chao‐Jan Liao
- Department of Botany and Plant Pathology, Purdue University915 W. State St.West LafayetteIN47907USA
| | - Adedayo Adeyanju
- Department of Agronomy, Purdue University915 W. State St.West LafayetteIN47907USA
| | - Matthew Helm
- United States Department of Agriculture, Agricultural Research Service, Crop Production and Pest Control Research UnitWest LafayetteIN47907USA
| | - Damon Lisch
- Department of Botany and Plant Pathology, Purdue University915 W. State St.West LafayetteIN47907USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University915 W. State St.West LafayetteIN47907USA
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Bvindi C, Tang L, Lee S, Patrick RM, Yee ZR, Mengiste T, Li Y. Histone methyltransferases SDG33 and SDG34 regulate organ-specific nitrogen responses in tomato. Front Plant Sci 2022; 13:1005077. [PMID: 36311072 PMCID: PMC9606235 DOI: 10.3389/fpls.2022.1005077] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Histone posttranslational modifications shape the chromatin landscape of the plant genome and affect gene expression in response to developmental and environmental cues. To date, the role of histone modifications in regulating plant responses to environmental nutrient availability, especially in agriculturally important species, remains largely unknown. We describe the functions of two histone lysine methyltransferases, SET Domain Group 33 (SDG33) and SDG34, in mediating nitrogen (N) responses of shoots and roots in tomato. By comparing the transcriptomes of CRISPR edited tomato lines sdg33 and sdg34 with wild-type plants under N-supplied and N-starved conditions, we uncovered that SDG33 and SDG34 regulate overlapping yet distinct downstream gene targets. In response to N level changes, both SDG33 and SDG34 mediate gene regulation in an organ-specific manner: in roots, SDG33 and SDG34 regulate a gene network including Nitrate Transporter 1.1 (NRT1.1) and Small Auxin Up-regulated RNA (SAUR) genes. In agreement with this, mutations in sdg33 or sdg34 abolish the root growth response triggered by an N-supply; In shoots, SDG33 and SDG34 affect the expression of photosynthesis genes and photosynthetic parameters in response to N. Our analysis thus revealed that SDG33 and SDG34 regulate N-responsive gene expression and physiological changes in an organ-specific manner, thus presenting previously unknown candidate genes as targets for selection and engineering to improve N uptake and usage in crop plants.
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Affiliation(s)
- Carol Bvindi
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
| | - Liang Tang
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, United States
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
| | - Ryan M. Patrick
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, United States
| | - Zheng Rong Yee
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, United States
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
| | - Ying Li
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN, United States
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, United States
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Liao CJ, Hailemariam S, Sharon A, Mengiste T. Pathogenic strategies and immune mechanisms to necrotrophs: Differences and similarities to biotrophs and hemibiotrophs. Curr Opin Plant Biol 2022; 69:102291. [PMID: 36063637 DOI: 10.1016/j.pbi.2022.102291] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 07/20/2022] [Accepted: 07/23/2022] [Indexed: 06/15/2023]
Abstract
Pathogenesis in plant diseases is complex comprising diverse pathogen virulence and plant immune mechanisms. These pathogens cause damaging plant diseases by deploying specialized and generic virulence strategies that are countered by intricate resistance mechanisms. The significant challenges that necrotrophs pose to crop production are predicted to increase with climate change. Immunity to biotrophs and hemibiotrophs is dominated by intracellular receptors that recognize specific effectors and activate resistance. These mechanisms play only minor roles in resistance to necrotrophs. Pathogen- or host-derived conserved pattern molecules trigger immune responses that broadly contribute to plant immunity. However, certain pathogen or host-derived immune elicitors are enriched by the virulence activities of necrotrophs. Different plant hormones modulate systemic resistance and cell death that have differential impacts on resistance to pathogens of different lifestyles. Knowledge of mechanisms that contribute to resistance to necrotrophs has expanded. Besides toxins and cell wall degrading enzymes that dominate the pathogenesis of necrotrophs, other effectors with subtle contributions are being identified.
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Affiliation(s)
- Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN 47907, USA
| | - Sara Hailemariam
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN 47907, USA
| | - Amir Sharon
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN 47907, USA.
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Bvindi C, Lee S, Tang L, Mickelbart MV, Li Y, Mengiste T. Improved pathogen and stress tolerance in tomato mutants of SET domain histone 3 lysine methyltransferases. New Phytol 2022; 235:1957-1976. [PMID: 35633111 DOI: 10.1111/nph.18277] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Histone lysine methylations (HLMs) are implicated in control of gene expression in different eukaryotes. However, the role of HLMs in regulating desirable crop traits and the enzymes involved in these modifications are poorly understood. We studied the functions of tomato histone H3 lysine methyltransferases SET Domain Group 33 (SDG33) and SDG34 in biotic and abiotic stress responses. SDG33 and SDG34 gene edited mutants were altered in H3K36 and H3K4 methylations, and expression of genes involved in diverse processes and responses to biotic and abiotic stimuli. The double but not the single mutants show resistance to the fungal pathogen Botrytis cinerea. Interestingly, single mutants were tolerant to drought and the double mutant showed superior tolerance and plant growth consistent with independent and additive functions. Mutants maintained higher water status during drought and improved recovery and survival after lapse of drought. Notably, diminution of H3K4 and H3K36 trimethylation and expression of negative regulators in challenged plants contributes to stress tolerance of the mutants. Mutations in SDG33 and SDG34 are likely to remove predisposition to biotic and abiotic stress by disrupting permissive transcriptional context promoting expression of negative regulatory factors. These allows improvement of stress and pathogen tolerance, without growth trade-offs, through modification of histone epigenetic marks.
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Affiliation(s)
- Carol Bvindi
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Liang Tang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
| | - Michael V Mickelbart
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
| | - Ying Li
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
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Lee S, Fu F, Liao CJ, Mewa DB, Adeyanju A, Ejeta G, Lisch D, Mengiste T. Broad-spectrum fungal resistance in sorghum is conferred through the complex regulation of an immune receptor gene embedded in a natural antisense transcript. Plant Cell 2022; 34:1641-1665. [PMID: 35018449 PMCID: PMC9048912 DOI: 10.1093/plcell/koab305] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 12/09/2021] [Indexed: 06/12/2023]
Abstract
Sorghum (Sorghum bicolor), the fifth most widely grown cereal crop globally, provides food security for millions of people. Anthracnose caused by the fungus Colletotrichum sublineola is a major disease of sorghum worldwide. We discovered a major fungal resistance locus in sorghum composed of the nucleotide-binding leucine-rich repeat receptor gene ANTHRACNOSE RESISTANCE GENE1 (ARG1) that is completely nested in an intron of a cis-natural antisense transcript (NAT) gene designated CARRIER OF ARG1 (CARG). Susceptible genotypes express CARG and two alternatively spliced ARG1 transcripts encoding truncated proteins lacking the leucine-rich repeat domains. In resistant genotypes, elevated expression of an intact allele of ARG1, attributed to the loss of CARG transcription and the presence of miniature inverted-repeat transposable element sequences, resulted in broad-spectrum resistance to fungal pathogens with distinct virulence strategies. Increased ARG1 expression in resistant genotypes is also associated with higher histone H3K4 and H3K36 methylation. In susceptible genotypes, lower ARG1 expression is associated with reduced H3K4 and H3K36 methylation and increased expression of NATs of CARG. The repressive chromatin state associated with H3K9me2 is low in CARG-expressing genotypes within the CARG exon and higher in genotypes with low CARG expression. Thus, ARG1 is regulated by multiple mechanisms and confers broad-spectrum, strong resistance to fungal pathogens.
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Affiliation(s)
| | | | - Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907, USA
| | - Demeke B Mewa
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907, USA
| | - Adedayo Adeyanju
- Department of Agronomy, Purdue University, West Lafayette, Indiana 47907, USA
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, Indiana 47907, USA
| | - Damon Lisch
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907, USA
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Jaiswal N, Liao CJ, Mengesha B, Han H, Lee S, Sharon A, Zhou Y, Mengiste T. Regulation of plant immunity and growth by tomato receptor-like cytoplasmic kinase TRK1. New Phytol 2022; 233:458-478. [PMID: 34655240 DOI: 10.1111/nph.17801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 10/11/2021] [Indexed: 05/27/2023]
Abstract
The molecular mechanisms of quantitative resistance (QR) to fungal pathogens and their relationships with growth pathways are poorly understood. We identified tomato TRK1 (TPK1b Related Kinase1) and determined its functions in tomato QR and plant growth. TRK1 is a receptor-like cytoplasmic kinase that complexes with tomato LysM Receptor Kinase (SlLYK1). SlLYK1 and TRK1 are required for chitin-induced fungal resistance, accumulation of reactive oxygen species, and expression of immune response genes. Notably, TRK1 and SlLYK1 regulate SlMYC2, a major transcriptional regulator of jasmonic acid (JA) responses and fungal resistance, at transcriptional and post-transcriptional levels. Further, TRK1 is also required for maintenance of proper meristem growth, as revealed by the ectopic meristematic activity, enhanced branching, and altered floral structures in TRK1 RNAi plants. Consistently, TRK1 interacts with SlCLV1 and SlWUS, and TRK1 RNAi plants show increased expression of SlCLV3 and SlWUS in shoot apices. Interestingly, TRK1 suppresses chitin-induced gene expression in meristems but promotes expression of the same genes in leaves. SlCLV1 and TRK1 perform contrasting functions in defense but similar functions in plant growth. Overall, through molecular and biochemical interactions with critical regulators, TRK1 links upstream defense and growth signals to downstream factor in fungal resistance and growth homeostasis response regulators.
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Affiliation(s)
- Namrata Jaiswal
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Bemnet Mengesha
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Han Han
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Amir Sharon
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Yun Zhou
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA
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Bi K, Scalschi L, Jaiswal N, Mengiste T, Fried R, Sanz AB, Arroyo J, Zhu W, Masrati G, Sharon A. The Botrytis cinerea Crh1 transglycosylase is a cytoplasmic effector triggering plant cell death and defense response. Nat Commun 2021; 12:2166. [PMID: 33846308 PMCID: PMC8042016 DOI: 10.1038/s41467-021-22436-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 03/10/2021] [Indexed: 02/01/2023] Open
Abstract
Crh proteins catalyze crosslinking of chitin and glucan polymers in fungal cell walls. Here, we show that the BcCrh1 protein from the phytopathogenic fungus Botrytis cinerea acts as a cytoplasmic effector and elicitor of plant defense. BcCrh1 is localized in vacuoles and the endoplasmic reticulum during saprophytic growth. However, upon plant infection, the protein accumulates in infection cushions; it is then secreted to the apoplast and translocated into plant cells, where it induces cell death and defense responses. Two regions of 53 and 35 amino acids are sufficient for protein uptake and cell death induction, respectively. BcCrh1 mutant variants that are unable to dimerize lack transglycosylation activity, but are still able to induce plant cell death. Furthermore, Arabidopsis lines expressing the bccrh1 gene exhibit reduced sensitivity to B. cinerea, suggesting a potential use of the BcCrh1 protein in plant immunization against this necrotrophic pathogen.
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Affiliation(s)
- Kai Bi
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan City, Hubei Province, China
| | - Loredana Scalschi
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- Plant Physiology Area, Biochemistry and Biotechnology Group, Department CAMN, University Jaume I, Castellón, Spain
| | - Namrata Jaiswal
- Department of Botany and Plant Pathology, College of Agriculture, Purdue University, West Lafayette, IN, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, College of Agriculture, Purdue University, West Lafayette, IN, USA
| | - Renana Fried
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Ana Belén Sanz
- Dpto. Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense, IRYCIS, Madrid, Spain
| | - Javier Arroyo
- Dpto. Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense, IRYCIS, Madrid, Spain
| | - Wenjun Zhu
- College of Life Science and Technology, Wuhan Polytechnic University, Wuhan City, Hubei Province, China
| | - Gal Masrati
- School of Neurobiology, Biochemistry and Biophysics, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Amir Sharon
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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Nida H, Girma G, Mekonen M, Tirfessa A, Seyoum A, Bejiga T, Birhanu C, Dessalegn K, Senbetay T, Ayana G, Tesso T, Ejeta G, Mengiste T. Genome-wide association analysis reveals seed protein loci as determinants of variations in grain mold resistance in sorghum. Theor Appl Genet 2021; 134:1167-1184. [PMID: 33452894 DOI: 10.1007/s00122-020-03762-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/30/2020] [Indexed: 06/12/2023]
Abstract
GWAS analysis revealed variations at loci harboring seed storage, late embryogenesis abundant protein, and a tannin biosynthesis gene associated with sorghum grain mold resistance. Grain mold is the most important disease of sorghum [Sorghum bicolor (L.) Moench]. It starts at the early stages of grain development due to concurrent infection by multiple fungal species. The genetic architecture of resistance to grain mold is poorly understood. Using a diverse set of 635 Ethiopian sorghum accessions, we conducted a multi-stage disease rating for resistance to grain mold under natural infestation in the field. Through genome-wide association analyses with 173,666 SNPs and multiple models, two novel loci were identified that were consistently associated with grain mold resistance across environments. Sequence variation at new loci containing sorghum KAFIRIN gene encoding a seed storage protein affecting seed texture and LATE EMBRYOGENESIS ABUNDANT 3 (LEA3) gene encoding a protein that accumulates in seeds, previously implicated in stress tolerance, were significantly associated with grain mold resistance. The KAFIRIN and LEA3 loci were also significant factors in grain mold resistance in accessions with non-pigmented grains. Moreover, we consistently detected the known SNP (S4_62316425) in TAN1 gene, a regulator of tannin accumulation in sorghum grain to be significantly associated with grain mold resistance. Identification of loci associated with new mechanisms of resistance provides fresh insight into genetic control of the trait, while the highly resistant accessions can serve as sources of resistance genes for breeding. Overall, our association data suggest the critical role of loci harboring seed protein genes and implicate grain chemical and physical properties in sorghum grain mold resistance.
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Affiliation(s)
- Habte Nida
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Gezahegn Girma
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Moges Mekonen
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Alemu Tirfessa
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Amare Seyoum
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Tamirat Bejiga
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Chemeda Birhanu
- Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia
| | - Kebede Dessalegn
- Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia
| | - Tsegau Senbetay
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Getachew Ayana
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Tesfaye Tesso
- Department of Agronomy, Kansas State University, 3007 Throckmorton PSC, 1712 Claflin Road, Manhattan, KS, 66506, USA
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA.
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12
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Zhu Y, Huang P, Guo P, Chong L, Yu G, Sun X, Hu T, Li Y, Hsu CC, Tang K, Zhou Y, Zhao C, Gao W, Tao WA, Mengiste T, Zhu JK. CDK8 is associated with RAP2.6 and SnRK2.6 and positively modulates abscisic acid signaling and drought response in Arabidopsis. New Phytol 2020; 228:1573-1590. [PMID: 32619295 DOI: 10.1111/nph.16787] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 06/20/2020] [Indexed: 06/11/2023]
Abstract
CDK8 is a key subunit of Mediator complex, a large multiprotein complex that is a fundamental part of the conserved eukaryotic transcriptional machinery. However, the biological functions of CDK8 in plant abiotic stress responses remain largely unexplored. Here, we demonstrated CDK8 as a critical regulator in the abscisic acid (ABA) signaling and drought response pathways in Arabidopsis. Compared to wild-type, cdk8 mutants showed reduced sensitivity to ABA, impaired stomatal apertures and hypersensitivity to drought stress. Transcriptomic and chromatin immunoprecipitation analysis revealed that CDK8 positively regulates the transcription of several ABA-responsive genes, probably through promoting the recruitment of RNA polymerase II to their promoters. We discovered that both CDK8 and SnRK2.6 interact physically with an ERF/AP2 transcription factor RAP2.6, which can directly bind to the promoters of RD29A and COLD-REGULATED 15A (COR15A) with GCC or DRE elements, thereby promoting their expression. Importantly, we also showed that CDK8 is essential for the ABA-induced expression of RAP2.6 and RAP2.6-mediated upregulation of ABA-responsive genes, indicating that CDK8 could link the SnRK2.6-mediated ABA signaling to RNA polymerase II to promote immediate transcriptional response to ABA and drought signals. Overall, our data provide new insights into the roles of CDK8 in modulating ABA signaling and drought responses.
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Affiliation(s)
- Yingfang Zhu
- State Key Laboratory of Crop Stress Adaptation and Improvement, Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475001, China
| | - Pengcheng Huang
- State Key Laboratory of Crop Stress Adaptation and Improvement, Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475001, China
| | - Pengcheng Guo
- State Key Laboratory of Crop Stress Adaptation and Improvement, Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475001, China
| | - Leelyn Chong
- State Key Laboratory of Crop Stress Adaptation and Improvement, Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475001, China
| | - Gaobo Yu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163711, China
| | - Xiaoli Sun
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
- Crop Stress Molecular Biology Laboratory, Heilongjiang Bayi Agricultural University, Daqing, 163711, China
| | - Tao Hu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Yuan Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Chuan-Chih Hsu
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Kai Tang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Yun Zhou
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Chunzhao Zhao
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Wei Gao
- State Key Laboratory of Crop Stress Adaptation and Improvement, Key Laboratory of Cotton Biology, School of Life Sciences, Henan University, Kaifeng, 475001, China
| | - W Andy Tao
- Department of Biochemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Jian-Kang Zhu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47907, USA
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
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13
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Abstract
BACKGROUND Anthracnose is a damaging disease of sorghum caused by the fungal pathogen Colletotrichum sublineolum. Genome-wide mRNA and microRNA (miRNA) profiles of resistant and susceptible sorghum genotypes were studied to understand components of immune responses, and fungal induced miRNA and target gene networks. RESULTS A total of 18 mRNA and 12 miRNA libraries from resistant and susceptible sorghum lines were sequenced prior to and after inoculation with C. sublineolum. Significant differences in transcriptomes of the susceptible and resistant genotypes were observed with dispersion distance and hierarchical cluster tree analyses. Of the total 33,032 genes predicted in the sorghum genome, 19,593 were induced by C. sublineolum, and 15,512 were differentially expressed (DEGs) between the two genotypes. The resistant line was marked by significant reprogramming of the transcriptome at 24 h post inoculation (hpi), and a decrease at 48 hpi, whereas the susceptible line displayed continued changes in gene expression concordant with elevated fungal growth in the susceptible genotype. DEGs encode proteins implicated in diverse functions including photosynthesis, synthesis of tetrapyrrole, carbohydrate and secondary metabolism, immune signaling, and chitin binding. Genes encoding immune receptors, MAPKs, pentatricopeptide repeat proteins, and WRKY transcription factors were induced in the resistant genotype. In a parallel miRNA profiling, the susceptible line displayed greater number of differentially expressed miRNAs than the resistant line indicative of a widespread suppression of gene expression. Interestingly, we found 75 miRNAs, including 36 novel miRNAs, which were differentially expressed in response to fungal inoculation. The expression of 50 miRNAs was significantly different between resistant and susceptible lines. Subsequently, for 35 differentially expressed miRNAs, the corresponding 149 target genes were identified. Expression of 56 target genes were significantly altered after inoculation, showing inverse expression with the corresponding miRNAs. CONCLUSIONS We provide insights into genome wide dynamics of mRNA and miRNA profiles, biological and cellular processes underlying host responses to fungal infection in sorghum. Resistance is correlated with early transcriptional reprogramming of genes in various pathways. Fungal induced genes, miRNAs and their targets with a potential function in host responses to anthracnose were identified, opening avenues for genetic dissection of resistance mechanisms.
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Affiliation(s)
- Fuyou Fu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 USA
- Present address: Agriculture and Agri-Food Canada, Plant Gene Resources of Canada, Saskatoon Research and Development Centre, 107 Science Place, Saskatoon, SK S7N 0X2 Canada
| | - Gezahegn Girma
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907 USA
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14
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Girma G, Nida H, Tirfessa A, Lule D, Bejiga T, Seyoum A, Mekonen M, Nega A, Dessalegn K, Birhanu C, Bekele A, Gebreyohannes A, Ayana G, Tesso T, Ejeta G, Mengiste T. A comprehensive phenotypic and genomic characterization of Ethiopian sorghum germplasm defines core collection and reveals rich genetic potential in adaptive traits. Plant Genome 2020; 13:e20055. [PMID: 33217211 DOI: 10.1002/tpg2.20055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Understanding population genetic structure and diversity of a crop is essential in designing selection strategies in plant breeding. About 2010 Ethiopian sorghum accessions were phenotyped for different traits at multiple locations. A subset of the collection, 1628 accessions, predominantly landraces, some improved varieties, and inbred lines were genotyped by sequencing. Phenotypic data revealed association of important traits with different sorghum growing agro-climatic regions, high genetic diversity and the presence of rare natural variation in the Ethiopian sorghum germplasm. Subsequent genotypic analysis determined optimum number of sub-populations, distinct cluster groups and ancestries of each sorghum accessions. To improve utilization of germplasm, a core subset of 387 lines were selected following posteriori grouping of genotypes based on cluster groups obtained through GBS analysis followed by stratified random sampling using quantitative traits. In order to evaluate how well this new sorghum and millet innovation lab (SMIL) collection from Ethiopia is represented within the largest world sorghum collection at United States Department of Agriculture - National Plant Germplasm System (USDA-NPGS) and the sorghum association panel (SAP), comparisons were conducted based on SNP data. The SMIL collection displayed high genetic diversity with some redundancy with the USDA-NPGS germplasm but SAP showed clear distinction. Furthermore, genome-environment association analysis identified candidate genes associated with adaptation to abiotic factors, that will be important for exploitation of adaptive potential to different environments. In summary, our results described the diversity and relationship of sorghum collections, representativeness of developed core and provide novel insights into candidate genes associated to abiotic stress tolerance.
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Affiliation(s)
- Gezahegn Girma
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Habte Nida
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
| | - Alemu Tirfessa
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Dagnachew Lule
- Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia
| | - Tamirat Bejiga
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Amare Seyoum
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Moges Mekonen
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Amare Nega
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Kebede Dessalegn
- Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia
| | - Chemeda Birhanu
- Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia
| | | | - Adane Gebreyohannes
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Getachew Ayana
- Ethiopian Institute of Agricultural Research, P.O. Box 2003, Addis Ababa, Ethiopia
| | - Tesfaye Tesso
- Department of Agronomy, Kansas State University, 3007 Throckmorton PSC 1712 Claflin Road, Manhattan, KS, 66506, USA
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, 47907, USA
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15
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Abdelrazek S, Choudhari S, Thimmapuram J, Simon P, Colley M, Mengiste T, Hoagland L. Changes in the core endophytic mycobiome of carrot taproots in response to crop management and genotype. Sci Rep 2020; 10:13685. [PMID: 32792547 PMCID: PMC7426841 DOI: 10.1038/s41598-020-70683-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 07/30/2020] [Indexed: 12/24/2022] Open
Abstract
Fungal endophytes can influence production and post-harvest challenges in carrot, though the identity of these microbes as well as factors affecting their composition have not yet been determined, which prevents growers from managing these organisms to improve crop performance. Consequently, we characterized the endophytic mycobiome in the taproots of three carrot genotypes that vary in resistance to two pathogens grown in a trial comparing organic and conventional crop management using Illumina sequencing of the internal transcribed spacer (ITS) gene. A total of 1,480 individual operational taxonomic units (OTUs) were identified. Most were consistent across samples, indicating that they are part of a core mycobiome, though crop management influenced richness and diversity, likely in response to differences in soil properties. There were also differences in individual OTUs among genotypes and the nematode resistant genotype was most responsive to management system indicating that it has greater control over its endophytic mycobiome, which could potentially play a role in resistance. Members of the Ascomycota were most dominant, though the exact function of most taxa remains unclear. Future studies aimed at overcoming difficulties associated with isolating fungal endophytes are needed to identify these microbes at the species level and elucidate their specific functional roles.
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Affiliation(s)
- Sahar Abdelrazek
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, USA
| | - Sulbha Choudhari
- Advanced Biomedical and Computational Sciences, Frederick National Laboratory for Cancer Research, Frederick, MD, USA.,Bioinformatics Core, Purdue University, West Lafayette, IN, USA
| | | | - Philipp Simon
- USDA-ARS Agriculture Research Service, Madison, WI, USA
| | | | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, USA
| | - Lori Hoagland
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, USA.
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16
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Abdelrazek S, Simon P, Colley M, Mengiste T, Hoagland L. Crop management system and carrot genotype affect endophyte composition and Alternaria dauci suppression. PLoS One 2020; 15:e0233783. [PMID: 32497087 PMCID: PMC7272071 DOI: 10.1371/journal.pone.0233783] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 05/12/2020] [Indexed: 11/23/2022] Open
Abstract
Managing pests in carrot production is challenging. Endophytic microbes have been demonstrated to improve the health and productivity of many crops, but factors affecting endophyte dynamics in carrot is still not well understood. The goal of this study was to determine how crop management system and carrot genotype interact to affect the composition and potential of endophytes to mitigate disease caused by Alternaria dauci, an important carrot pathogen. Twenty-eight unique isolates were collected from the taproots of nine diverse genotypes of carrot grown in a long-term trial comparing organic and conventional management. Antagonistic activity was quantified using an in vitro assay, and potential for individual isolates to mitigate disease was evaluated in greenhouse trials using two carrot cultivars. Results confirm that carrot taproots are colonized by an abundant and diverse assortment of bacteria and fungi representing at least distinct 13 genera. Soils in the organic system had greater total organic matter, microbial biomass and activity than the conventional system and endophyte composition in taproots grown in this system were more abundant and diverse, and had greater antagonistic activity. Carrot genotype also affected endophyte abundance as well as potential for individual isolates to affect seed germination, seedling growth and tolerance to A. dauci. The benefits of endophytes on carrot growth were greatest when plants were subject to A. dauci stress, highlighting the importance of environmental conditions in the functional role of endophytes. Results of this study provide evidence that endophytes can play an important role in improving carrot performance and mediating resistance to A. dauci, and it may someday be possible to select for these beneficial plant-microbial relationships in carrot breeding programs. Implementing soil-building practices commonly used in organic farming systems has potential to promote these beneficial relationships and improve the health and productivity of carrot crops.
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Affiliation(s)
- Sahar Abdelrazek
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United State of America
| | - Philipp Simon
- USDA-ARS Agriculture Research Service, Madison, Wisconsin, United States of America
| | - Micaela Colley
- Organic Seed Alliance, Port Townsend, Washington, United States of America
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana, United States of America
| | - Lori Hoagland
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana, United State of America
- * E-mail:
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17
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Chen J, Mohan R, Zhang Y, Li M, Chen H, Palmer IA, Chang M, Qi G, Spoel SH, Mengiste T, Wang D, Liu F, Fu ZQ. NPR1 Promotes Its Own and Target Gene Expression in Plant Defense by Recruiting CDK8. Plant Physiol 2019; 181:289-304. [PMID: 31110139 PMCID: PMC6716257 DOI: 10.1104/pp.19.00124] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 05/10/2019] [Indexed: 05/19/2023]
Abstract
NPR1 (NONEXPRESSER OF PR GENES1) functions as a master regulator of the plant hormone salicylic acid (SA) signaling and plays an essential role in plant immunity. In the nucleus, NPR1 interacts with transcription factors to induce the expression of PR (PATHOGENESIS-RELATED) genes and thereby promote defense responses. However, the underlying molecular mechanism of PR gene activation is poorly understood. Furthermore, despite the importance of NPR1 in plant immunity, the regulation of NPR1 expression has not been extensively studied. Here, we show that SA promotes the interaction of NPR1 with both CDK8 (CYCLIN-DEPENDENT KINASE8) and WRKY18 (WRKY DNA-BINDING PROTEIN18) in Arabidopsis (Arabidopsis thaliana). NPR1 recruits CDK8 and WRKY18 to the NPR1 promoter, facilitating its own expression. Intriguingly, CDK8 and its associated Mediator subunits positively regulate NPR1 and PR1 expression and play a pivotal role in local and systemic immunity. Moreover, CDK8 interacts with WRKY6, WRKY18, and TGA transcription factors and brings RNA polymerase II to NPR1 and PR1 promoters and coding regions to facilitate their expression. Our studies reveal a mechanism in which NPR1 recruits CDK8, WRKY18, and TGA transcription factors along with RNA polymerase II in the presence of SA and thereby facilitates its own and target gene expression for the establishment of plant immunity.
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Affiliation(s)
- Jian Chen
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, People's Republic of China
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Rajinikanth Mohan
- Department of Biology, Duke University, Durham, North Carolina 27708
| | - Yuqiang Zhang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, People's Republic of China
| | - Min Li
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Huan Chen
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, People's Republic of China
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Ian Arthur Palmer
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Ming Chang
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, People's Republic of China
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
| | - Guang Qi
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
- State Key Laboratory of Wheat and Maize Crop Science and College of Agronomy, Henan Agricultural University, Zhengzhou 450002, People's Republic of China
| | - Steven H Spoel
- Department of Biology, Duke University, Durham, North Carolina 27708
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Daowen Wang
- State Key Laboratory of Wheat and Maize Crop Science and College of Agronomy, Henan Agricultural University, Zhengzhou 450002, People's Republic of China
| | - Fengquan Liu
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Nanjing 210014, People's Republic of China
| | - Zheng Qing Fu
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina 29208
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18
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Huang L, Li X, Li Y, Yin X, Li Y, Wu B, Mo H, Liao CJ, Mengiste T, Guo W, Dai M, Zhang C. Endosidin2-14 Targets the Exocyst Complex in Plants and Fungal Pathogens to Inhibit Exocytosis. Plant Physiol 2019; 180:1756-1770. [PMID: 31072814 PMCID: PMC6752926 DOI: 10.1104/pp.18.01457] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 04/29/2019] [Indexed: 05/29/2023]
Abstract
The evolutionarily conserved octameric exocyst complex tethers secretory vesicles to the site of membrane fusion during exocytosis. The plant exocyst complex functions in cell wall biosynthesis, polarized growth, stress responses, and hormone signaling. In fungal pathogens, the exocyst complex is required for growth, development, and pathogenesis. Endosidin2 (ES2) is known to inhibit exocytosis in plant and mammalian cells by targeting the EXO70 subunit of the exocyst complex. Here we show that an analog of ES2, ES2-14, targets plant and two fungal EXO70s. A lower dosage of ES2-14 than of ES2 is required to inhibit plant growth, plant exocytic trafficking, and fungal growth. ES2-14 treatments inhibit appressorium formation and reduce lesion sizes caused by Magnaporthe oryzae Inhibition of EXO70 by ES2-14 in Botrytis cinerea also reduces its virulence in Arabidopsis (Arabidopsis thaliana). Interestingly, ES2-14 did not affect EXO70 localization or transferrin recycling in mammalian cells. Overall, our results indicate that a minor change in ES2 affects its specificity in targeting EXO70s in different organisms and they demonstrate the potential of using ES2-14 to study the mechanisms of plant and fungal exocytosis and the roles of exocytosis in fungus-plant interactions.
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Affiliation(s)
- Lei Huang
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
- Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana 47907
| | - Xiaohui Li
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
- Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana 47907
| | - Yang Li
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Xianglin Yin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907
| | - Yong Li
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907
| | - Bin Wu
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Huaping Mo
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907
| | - Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Wei Guo
- Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Mingji Dai
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907
| | - Chunhua Zhang
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
- Purdue Center for Plant Biology, Purdue University, West Lafayette, Indiana 47907
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19
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Girma G, Nida H, Seyoum A, Mekonen M, Nega A, Lule D, Dessalegn K, Bekele A, Gebreyohannes A, Adeyanju A, Tirfessa A, Ayana G, Taddese T, Mekbib F, Belete K, Tesso T, Ejeta G, Mengiste T. A Large-Scale Genome-Wide Association Analyses of Ethiopian Sorghum Landrace Collection Reveal Loci Associated With Important Traits. Front Plant Sci 2019; 10:691. [PMID: 31191590 PMCID: PMC6549537 DOI: 10.3389/fpls.2019.00691] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/08/2019] [Indexed: 05/20/2023]
Abstract
The eastern Africa region, Ethiopia and its surroundings, is considered as the center of origin and diversity for sorghum, and has contributed to global sorghum genetic improvement. The germplasm from this region harbors enormous genetic variation for various traits but little is known regarding the genetic architecture of most traits. Here, 1425 Ethiopian landrace accessions were phenotyped under field conditions for presence or absence of awns, panicle compactness and shape, panicle exsertion, pericarp color, glume cover, plant height and smut resistance under diverse environmental conditions in Ethiopia. In addition, F1 hybrids obtained from a subset of 1341 accessions crossed to an A1 cytoplasmic male sterile line, ATx623, were scored for fertility/sterility reactions. Subsequently, genotyping-by-sequencing generated a total of 879,407 SNPs from which 72,190 robust SNP markers were selected after stringent quality control (QC). Pairwise distance-based hierarchical clustering identified 11 distinct groups. Of the genotypes assigned to either one of the 11 sub-populations, 65% had high ancestry membership coefficient with the likelihood of more than 0.60 and the remaining 35% represented highly admixed accessions. A genome-wide association study (GWAS) identified loci and SNPs associated with aforementioned traits. GWAS based on compressed mixed linear model (CMLM) identified SNPs with significant association (FDR ≤ 0.05) to the different traits studied. The percentage of total phenotypic variation explained with significant SNPs across traits ranged from 2 to 43%. Candidate genes showing significant association with different traits were identified. The sorghum bHLH transcription factor, ABORTED MICROSPORES was identified as a strong candidate gene conditioning male fertility. Notably, sorghum CLAVATA1 receptor like kinase, known for regulation of plant growth, and the ETHYLENE RESPONSIVE TRANSCRIPTION FACTOR gene RAP2-7, known to suppress transition to flowering, were significantly associated with plant height. In addition, the YELLOW SEED1 like MYB transcription factor and TANNIN1 showed strong association with pericarp color validating previous observations. Overall, the genetic architecture of natural variation representing the complex Ethiopian sorghum germplasm was established. The study contributes to the characterization of genes and alleles controlling agronomic traits, and will serve as a source of markers for molecular breeding.
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Affiliation(s)
- Gezahegn Girma
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Habte Nida
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Amare Seyoum
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Moges Mekonen
- Chiro Agricultural Research Center, Ethiopian Institute of Agricultural Research, Chiro, Ethiopia
| | - Amare Nega
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Dagnachew Lule
- Bako Agricultural Research Center, Oromia Agricultural Research Institute, Bako, Ethiopia
| | - Kebede Dessalegn
- Bako Agricultural Research Center, Oromia Agricultural Research Institute, Bako, Ethiopia
| | - Alemnesh Bekele
- School of Plant Sciences, Haramaya University, Dire Dawa, Ethiopia
| | - Adane Gebreyohannes
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Adedayo Adeyanju
- Department of Agronomy, Purdue University, West Lafayette, IN, United States
| | - Alemu Tirfessa
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Getachew Ayana
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Taye Taddese
- Malkassa Agricultural Research Center, Ethiopian Institute of Agricultural Research, Adama, Ethiopia
| | - Firew Mekbib
- School of Plant Sciences, Haramaya University, Dire Dawa, Ethiopia
| | - Ketema Belete
- School of Plant Sciences, Haramaya University, Dire Dawa, Ethiopia
| | - Tesfaye Tesso
- Department of Agronomy, Kansas State University, Manhattan, KS, United States
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, IN, United States
- *Correspondence: Gebisa Ejeta,
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
- Tesfaye Mengiste,
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20
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Nida H, Girma G, Mekonen M, Lee S, Seyoum A, Dessalegn K, Tadesse T, Ayana G, Senbetay T, Tesso T, Ejeta G, Mengiste T. Identification of sorghum grain mold resistance loci through genome wide association mapping. J Cereal Sci 2019. [DOI: 10.1016/j.jcs.2018.12.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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21
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Xu S, Liao CJ, Jaiswal N, Lee S, Yun DJ, Lee SY, Garvey M, Kaplan I, Mengiste T. Tomato PEPR1 ORTHOLOG RECEPTOR-LIKE KINASE1 Regulates Responses to Systemin, Necrotrophic Fungi, and Insect Herbivory. Plant Cell 2018; 30:2214-2229. [PMID: 30131419 PMCID: PMC6181013 DOI: 10.1105/tpc.17.00908] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 07/23/2018] [Accepted: 08/15/2018] [Indexed: 05/20/2023]
Abstract
Endogenous peptides regulate plant immunity and growth. Systemin, a peptide specific to the Solanaceae, is known for its functions in plant responses to insect herbivory and pathogen infections. Here, we describe the identification of the tomato (Solanum lycopersicum) PEPR1/2 ORTHOLOG RECEPTOR-LIKE KINASE1 (PORK1) as the TOMATO PROTEIN KINASE1b (TPK1b) interacting protein and demonstrate its biological functions in systemin signaling and tomato immune responses. Tomato PORK1 RNA interference (RNAi) plants with significantly reduced PORK1 expression showed increased susceptibility to tobacco hornworm (Manduca sexta), reduced seedling growth sensitivity to the systemin peptide, and compromised systemin-mediated resistance to Botrytis cinerea. Systemin-induced expression of Proteinase Inhibitor II (PI-II), a classical marker for systemin signaling, was abrogated in PORK1 RNAi plants. Similarly, in response to systemin and wounding, the expression of jasmonate pathway genes was attenuated in PORK1 RNAi plants. TPK1b, a key regulator of tomato defense against B. cinerea and M. sexta, was phosphorylated by PORK1. Interestingly, wounding- and systemin-induced phosphorylation of TPK1b was attenuated when PORK1 expression was suppressed. Our data suggest that resistance to B. cinerea and M. sexta is dependent on PORK1-mediated responses to systemin and subsequent phosphorylation of TPK1b. Altogether, PORK1 regulates tomato systemin, wounding, and immune responses.
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Affiliation(s)
- Siming Xu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Namrata Jaiswal
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Dae-Jin Yun
- Department of Biomedical Science and Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, South Korea
| | - Sang Yeol Lee
- Division of Applied Life Sciences (BK 21 Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Michael Garvey
- Department of Entomology, Smith Hall, Purdue University, West Lafayette, Indiana 47907-2089
| | - Ian Kaplan
- Department of Biomedical Science and Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, South Korea
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
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22
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Park J, Lim CJ, Shen M, Park HJ, Cha JY, Iniesto E, Rubio V, Mengiste T, Zhu JK, Bressan RA, Lee SY, Lee BH, Jin JB, Pardo JM, Kim WY, Yun DJ. Epigenetic switch from repressive to permissive chromatin in response to cold stress. Proc Natl Acad Sci U S A 2018; 115:E5400-E5409. [PMID: 29784800 PMCID: PMC6003311 DOI: 10.1073/pnas.1721241115] [Citation(s) in RCA: 113] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Switching from repressed to active status in chromatin regulation is part of the critical responses that plants deploy to survive in an ever-changing environment. We previously reported that HOS15, a WD40-repeat protein, is involved in histone deacetylation and cold tolerance in Arabidopsis However, it remained unknown how HOS15 regulates cold responsive genes to affect cold tolerance. Here, we show that HOS15 interacts with histone deacetylase 2C (HD2C) and both proteins together associate with the promoters of cold-responsive COR genes, COR15A and COR47 Cold induced HD2C degradation is mediated by the CULLIN4 (CUL4)-based E3 ubiquitin ligase complex in which HOS15 acts as a substrate receptor. Interference with the association of HD2C and the COR gene promoters by HOS15 correlates with increased acetylation levels of histone H3. HOS15 also interacts with CBF transcription factors to modulate cold-induced binding to the COR gene promoters. Our results here demonstrate that cold induces HOS15-mediated chromatin modifications by degrading HD2C. This switches the chromatin structure status and facilitates recruitment of CBFs to the COR gene promoters. This is an apparent requirement to acquire cold tolerance.
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Affiliation(s)
- Junghoon Park
- Department of Biomedical Science and Engineering, Konkuk University, 05029 Seoul, South Korea
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Chae Jin Lim
- Department of Biomedical Science and Engineering, Konkuk University, 05029 Seoul, South Korea
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Mingzhe Shen
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Hee Jin Park
- Department of Biomedical Science and Engineering, Konkuk University, 05029 Seoul, South Korea
- Institute of Glocal Disease Control, Konkuk University, 05029 Seoul, Republic of Korea
| | - Joon-Yung Cha
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Elisa Iniesto
- Plant Molecular Genetics Department, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Cientificas, Campus de la Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Vicente Rubio
- Plant Molecular Genetics Department, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Cientificas, Campus de la Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - Jian-Kang Zhu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907
| | - Ray A Bressan
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907
| | - Sang Yeol Lee
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Byeong-Ha Lee
- Department of Life Science, Sogang University, 04107 Seoul, South Korea
| | - Jing Bo Jin
- Institute of Botany, Chinese Academy of Sciences, 100093 Beijing, China
| | - Jose M Pardo
- Institute of Plant Biochemistry and Photosynthesis, Consejo Superior de Investigaciones Cientificas, 41092 Seville, Spain
| | - Woe-Yeon Kim
- Division of Applied Life Science (BK21 plus Program), Plant Molecular Biology and Biotechnology Research Center, Institute of Agriculture and Life Science, Gyeongsang National University, 52828 Jinju, Republic of Korea
| | - Dae-Jin Yun
- Department of Biomedical Science and Engineering, Konkuk University, 05029 Seoul, South Korea;
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23
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Lapham R, Lee LY, Tsugama D, Lee S, Mengiste T, Gelvin SB. VIP1 and Its Homologs Are Not Required for Agrobacterium-Mediated Transformation, but Play a Role in Botrytis and Salt Stress Responses. Front Plant Sci 2018; 9:749. [PMID: 29946325 PMCID: PMC6005860 DOI: 10.3389/fpls.2018.00749] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/15/2018] [Indexed: 05/02/2023]
Abstract
The bZIP transcription factor VIP1 interacts with the Agrobacterium virulence protein VirE2, but the role of VIP1 in Agrobacterium-mediated transformation remains controversial. Previously tested vip1-1 mutant plants produce a truncated protein containing the crucial bZIP DNA-binding domain. We generated the CRISPR/Cas mutant vip1-2 that lacks this domain. The transformation susceptibility of vip1-2 and wild-type plants is similar. Because of potential functional redundancy among VIP1 homologs, we tested transgenic lines expressing VIP1 fused to a SRDX repression domain. All VIP1-SRDX transgenic lines showed wild-type levels of transformation, indicating that neither VIP1 nor its homologs are required for Agrobacterium-mediated transformation. Because VIP1 is involved in innate immune response signaling, we tested the susceptibility of vip1 mutant and VIP1-SRDX plants to Pseudomonas syringae and Botrytis cinerea. vip1 mutant and VIP1-SRDX plants show increased susceptibility to B. cinerea but not to P. syringae infection, suggesting a role for VIP1 in B. cinerea, but not in P. syringae, defense signaling. B. cinerea susceptibility is dependent on abscisic acid (ABA) which is also important for abiotic stress responses. The germination of vip1 mutant and VIP1-SRDX seeds is sensitive to exogenous ABA, suggesting a role for VIP1 in response to ABA. vip1 mutant and VIP1-SRDX plants show increased tolerance to growth in salt, indicating a role for VIP1 in response to salt stress.
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Affiliation(s)
- Rachelle Lapham
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
| | - Lan-Ying Lee
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
| | - Daisuke Tsugama
- Laboratory of Crop Physiology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Stanton B. Gelvin
- Department of Biological Sciences, Purdue University, West Lafayette, IN, United States
- *Correspondence: Stanton B. Gelvin, ;
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24
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Gobena D, Shimels M, Rich PJ, Ruyter-Spira C, Bouwmeester H, Kanuganti S, Mengiste T, Ejeta G. Mutation in sorghum LOW GERMINATION STIMULANT 1 alters strigolactones and causes Striga resistance. Proc Natl Acad Sci U S A 2017; 114:4471-4476. [PMID: 28396420 PMCID: PMC5410831 DOI: 10.1073/pnas.1618965114] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Striga is a major biotic constraint to sorghum production in semiarid tropical Africa and Asia. Genetic resistance to this parasitic weed is the most economically feasible control measure. Mutant alleles at the LGS1 (LOW GERMINATION STIMULANT 1) locus drastically reduce Striga germination stimulant activity. We provide evidence that the responsible gene at LGS1 codes for an enzyme annotated as a sulfotransferase and show that functional loss of this gene results in a change of the dominant strigolactone (SL) in root exudates from 5-deoxystrigol, a highly active Striga germination stimulant, to orobanchol, an SL with opposite stereochemistry. Orobanchol, although not previously reported in sorghum, functions in the multiple SL roles required for normal growth and environmental responsiveness but does not stimulate germination of Striga This work describes the identification of a gene regulating Striga resistance and the underlying protective chemistry resulting from mutation.
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Affiliation(s)
- Daniel Gobena
- Department of Agronomy, Purdue University, West Lafayette, IN 47907
| | - Mahdere Shimels
- Laboratory of Plant Physiology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Patrick J Rich
- Department of Agronomy, Purdue University, West Lafayette, IN 47907
| | - Carolien Ruyter-Spira
- Laboratory of Plant Physiology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Harro Bouwmeester
- Laboratory of Plant Physiology, Wageningen University, 6708 PB Wageningen, The Netherlands
| | - Satish Kanuganti
- Department of Agronomy, Purdue University, West Lafayette, IN 47907
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
| | - Gebisa Ejeta
- Department of Agronomy, Purdue University, West Lafayette, IN 47907;
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25
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Liao CJ, Lai Z, Lee S, Yun DJ, Mengiste T. Arabidopsis HOOKLESS1 Regulates Responses to Pathogens and Abscisic Acid through Interaction with MED18 and Acetylation of WRKY33 and ABI5 Chromatin. Plant Cell 2016; 28:1662-81. [PMID: 27317674 PMCID: PMC4981130 DOI: 10.1105/tpc.16.00105] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 06/16/2016] [Indexed: 05/03/2023]
Abstract
Arabidopsis thaliana HOOKLESS1 (HLS1) encodes a putative histone acetyltransferase with known functions in seedling growth. Here, we show that HLS1 regulates plant responses to pathogens and abscisic acid (ABA) through histone acetylation at chromatin of target loci. The hls1 mutants show impaired responses to bacterial and fungal infection, accelerated senescence, and impaired responses to ABA. HLS1 modulates the expression of WRKY33 and ABA INSENSITIVE5 (ABI5), known regulators of pathogen and ABA responses, respectively, through direct association with these loci. Histone 3 acetylation (H3Ac), a positive mark of transcription, at WRKY33 and ABI5 requires HLS1 function. ABA treatment and pathogen infection enhance HLS1 recruitment and H3Ac at WRKY33. HLS1 associates with Mediator, a eukaryotic transcription coregulatory complex, through direct interaction with mediator subunit 18 (MED18), with which it shares multiple functions. HLS1 recruits MED18 to the WRKY33 promoter, boosting WKRY33 expression, suggesting the synergetic action of HLS1 and MED18. By contrast, MED18 recruitment to ABI5 and transcriptional activation are independent of HLS1. ABA-mediated priming of resistance to fungal infection was abrogated in hls1 and wrky33 mutants but correlated with ABA-induced HLS1 accumulation. In sum, HLS1 provides a regulatory node in pathogen and hormone response pathways through interaction with the Mediator complex and important transcription factors.
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Affiliation(s)
- Chao-Jan Liao
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Zhibing Lai
- National Key Laboratory of Crop Genetics Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Dae-Jin Yun
- Division of Applied Life Sciences (BK 21 Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
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26
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Lee S, Fu F, Xu S, Lee SY, Yun DJ, Mengiste T. Global Regulation of Plant Immunity by Histone Lysine Methyl Transferases. Plant Cell 2016; 28:1640-61. [PMID: 27354553 PMCID: PMC4981126 DOI: 10.1105/tpc.16.00012] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 05/25/2016] [Accepted: 06/24/2016] [Indexed: 05/17/2023]
Abstract
Posttranslational modification of histones modulates gene expression affecting diverse biological functions. We showed that the Arabidopsis thaliana histone methyl transferases SET DOMAIN GROUP8 (SDG8) and SDG25 regulate pep1-, flg22-, and effector-triggered immunity as well as systemic acquired resistance. Genome-wide basal and induced transcriptome changes regulated by SDG8 and/or SDG25 showed that two genes of the SDG-dependent transcriptome, CAROTENOID ISOMERASE2 (CCR2) and ECERIFERUM3 (CER3), were also required for plant immunity, establishing mechanisms in defense functions for SDG8 and SDG25. CCR2 catalyzes the biosynthesis of carotenoids, whereas CER3 is involved in the biosynthesis of cuticular wax. SDG8 and SDG25 affected distinct and overlapping global and locus-specific histone H3 lysine 4 (H3K4) and histone H3 lysine 36 (H3K36) methylations. Loss of immunity in sdg mutants was attributed to altered global and CCR2- and CER3-specific histone lysine methylation (HLM). Loss of immunity in sdg, ccr2, and cer3 mutants was also associated with diminished accumulation of lipids and loss of cuticle integrity. In addition, sdg8 and sdg25 mutants were impaired in H2B ubiquitination (H2Bubn) at CCR2, CER3, and H2Bubn regulated R gene, SNC1, revealing crosstalk between the two types of histone modifications. In summary, SDG8 and SDG25 contribute to plant immunity directly through HLM or indirectly through H2Bubn and by regulating expression of plant immunity genes, accumulation of lipids, biosynthesis of carotenoids, and maintenance of cuticle integrity.
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Affiliation(s)
- Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Fuyou Fu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Siming Xu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Sang Yeol Lee
- Division of Applied Life Sciences (BK 21 Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Dae-Jin Yun
- Division of Applied Life Sciences (BK 21 Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
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27
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Yoo JY, Ko KS, Seo HK, Park S, Fanata WID, Harmoko R, Ramasamy NK, Thulasinathan T, Mengiste T, Lim JM, Lee SY, Lee KO. Limited Addition of the 6-Arm β1,2-linked N-Acetylglucosamine (GlcNAc) Residue Facilitates the Formation of the Largest N-Glycan in Plants. J Biol Chem 2015; 290:16560-72. [PMID: 26001781 DOI: 10.1074/jbc.m115.653162] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Indexed: 12/22/2022] Open
Abstract
The most abundant N-glycan in plants is the paucimannosidic N-glycan with core β1,2-xylose and α1,3-fucose residues (Man3XylFuc(GlcNAc)2). Here, we report a mechanism in Arabidopsis thaliana that efficiently produces the largest N-glycan in plants. Genetic and biochemical evidence indicates that the addition of the 6-arm β1,2-GlcNAc residue by N-acetylglucosaminyltransferase II (GnTII) is less effective than additions of the core β1,2-xylose and α1,3-fucose residues by XylT, FucTA, and FucTB in Arabidopsis. Furthermore, analysis of gnt2 mutant and 35S:GnTII transgenic plants shows that the addition of the 6-arm non-reducing GlcNAc residue to the common N-glycan acceptor GlcNAcMan3(GlcNAc)2 inhibits additions of the core β1,2-xylose and α1,3-fucose residues. Our findings indicate that plants limit the rate of the addition of the 6-arm GlcNAc residue to the common N-glycan acceptor as a mechanism to facilitate formation of the prevalent N-glycans with Man3XylFuc(GlcNAc)2 and (GlcNAc)2Man3XylFuc(GlcNAc)2 structures.
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Affiliation(s)
- Jae Yong Yoo
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Ki Seong Ko
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Hyun-Kyeong Seo
- Department of Chemistry, Changwon National University, 9-Sarim, Changwon 641-773, Korea, and
| | - Seongha Park
- Department of Chemistry, Changwon National University, 9-Sarim, Changwon 641-773, Korea, and
| | - Wahyu Indra Duwi Fanata
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Rikno Harmoko
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Nirmal Kumar Ramasamy
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Thiyagarajan Thulasinathan
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | - Jae-Min Lim
- Department of Chemistry, Changwon National University, 9-Sarim, Changwon 641-773, Korea, and
| | - Sang Yeol Lee
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea
| | - Kyun Oh Lee
- From the Division of Applied Life Science and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, 501 Jinju-daero, Jinju 660-701, Korea,
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28
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Park HC, Lee S, Park B, Choi W, Kim C, Lee S, Chung WS, Lee SY, Sabir J, Bressan RA, Bohnert HJ, Mengiste T, Yun DJ. Pathogen associated molecular pattern (PAMP)-triggered immunity is compromised under C-limited growth. Mol Cells 2015; 38:40-50. [PMID: 25387755 PMCID: PMC4314131 DOI: 10.14348/molcells.2015.2165] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/24/2013] [Accepted: 10/14/2014] [Indexed: 11/27/2022] Open
Abstract
In the interaction between plants and pathogens, carbon (C) resources provide energy and C skeletons to maintain, among many functions, the plant immune system. However, variations in C availability on pathogen associated molecular pattern (PAMP) triggered immunity (PTI) have not been systematically examined. Here, three types of starch mutants with enhanced susceptibility to Pseudomonas syringae pv. tomato DC3000 hrcC were examined for PTI. In a dark period-dependent manner, the mutants showed compromised induction of a PTI marker, and callose accumulation in response to the bacterial PAMP flagellin, flg22. In combination with weakened PTI responses in wild type by inhibition of the TCA cycle, the experiments determined the necessity of C-derived energy in establishing PTI. Global gene expression analyses identified flg22 responsive genes displaying C supply-dependent patterns. Nutrient recycling-related genes were regulated similarly by C-limitation and flg22, indicating re-arrangements of expression programs to redirect resources that establish or strengthen PTI. Ethylene and NAC transcription factors appear to play roles in these processes. Under C-limitation, PTI appears compromised based on suppression of genes required for continued biosynthetic capacity and defenses through flg22. Our results provide a foundation for the intuitive perception of the interplay between plant nutrition status and pathogen defense.
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Affiliation(s)
- Hyeong Cheol Park
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
- Bureau of Ecological Conservation Reseach, National Institute of Ecology, Seocheon 325-813,
Korea
| | - Shinyoung Lee
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907,
USA
| | - Bokyung Park
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
| | - Wonkyun Choi
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
- Bureau of Ecological Conservation Reseach, National Institute of Ecology, Seocheon 325-813,
Korea
| | - Chanmin Kim
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
| | - Sanghun Lee
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907,
USA
| | - Woo Sik Chung
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
| | - Sang Yeol Lee
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
| | - Jamal Sabir
- College of Science, King Abdulaziz University, Jeddah 21589,
Kingdom of Saudi Arabia
| | - Ray A. Bressan
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907,
USA
- College of Science, King Abdulaziz University, Jeddah 21589,
Kingdom of Saudi Arabia
| | - Hans J. Bohnert
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
- College of Science, King Abdulaziz University, Jeddah 21589,
Kingdom of Saudi Arabia
- Departments of Plant Biology and of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801,
USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907,
USA
| | - Dae-Jin Yun
- Division of Applied Life Science (BK21 Plus Program) and Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701,
Korea
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Zhu Y, Schluttenhoffer CM, Wang P, Fu F, Thimmapuram J, Zhu JK, Lee SY, Yun DJ, Mengiste T. CYCLIN-DEPENDENT KINASE8 differentially regulates plant immunity to fungal pathogens through kinase-dependent and -independent functions in Arabidopsis. Plant Cell 2014; 26:4149-70. [PMID: 25281690 PMCID: PMC4247566 DOI: 10.1105/tpc.114.128611] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/28/2014] [Accepted: 09/17/2014] [Indexed: 05/18/2023]
Abstract
CYCLIN-DEPENDENT KINASE8 (CDK8) is a widely studied component of eukaryotic Mediator complexes. However, the biological and molecular functions of plant CDK8 are not well understood. Here, we provide evidence for regulatory functions of Arabidopsis thaliana CDK8 in defense and demonstrate its functional and molecular interactions with other Mediator and non-Mediator subunits. The cdk8 mutant exhibits enhanced resistance to Botrytis cinerea but susceptibility to Alternaria brassicicola. The contributions of CDK8 to the transcriptional activation of defensin gene PDF1.2 and its interaction with MEDIATOR COMPLEX SUBUNIT25 (MED25) implicate CDK8 in jasmonate-mediated defense. Moreover, CDK8 associates with the promoter of AGMATINE COUMAROYLTRANSFERASE to promote its transcription and regulate the biosynthesis of the defense-active secondary metabolites hydroxycinnamic acid amides. CDK8 also interacts with the transcription factor WAX INDUCER1, implying its additional role in cuticle development. In addition, overlapping functions of CDK8 with MED12 and MED13 and interactions between CDK8 and C-type cyclins suggest the conserved configuration of the plant Mediator kinase module. In summary, while CDK8's positive transcriptional regulation of target genes and its phosphorylation activities underpin its defense functions, the impaired defense responses in the mutant are masked by its altered cuticle, resulting in specific resistance to B. cinerea.
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Affiliation(s)
- Yingfang Zhu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | | | - Pengcheng Wang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907
| | - Fuyou Fu
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
| | | | - Jian-Kang Zhu
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907
| | - Sang Yeol Lee
- Division of Applied Life Sciences (BK21 Plus Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Dae-Jin Yun
- Division of Applied Life Sciences (BK21 Plus Program), Gyeongsang National University, Jinju City 660-701, Korea
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907
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Smith JE, Mengesha B, Tang H, Mengiste T, Bluhm BH. Resistance to Botrytis cinerea in Solanum lycopersicoides involves widespread transcriptional reprogramming. BMC Genomics 2014; 15:334. [PMID: 24885798 PMCID: PMC4035065 DOI: 10.1186/1471-2164-15-334] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 04/25/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Tomato (Solanum lycopersicum), one of the world's most important vegetable crops, is highly susceptible to necrotrophic fungal pathogens such as Botrytis cinerea and Alternaria solani. Improving resistance through conventional breeding has been hampered by a shortage of resistant germplasm and difficulties in introgressing resistance into elite germplasm without linkage drag. The goal of this study was to explore natural variation among wild Solanum species to identify new sources of resistance to necrotrophic fungi and dissect mechanisms underlying resistance against B. cinerea. RESULTS Among eight wild species evaluated for resistance against B. cinerea and A. solani, S. lycopersicoides expressed the highest levels of resistance against both pathogens. Resistance against B. cinerea manifested as containment of pathogen growth. Through next-generation RNA sequencing and de novo assembly of the S. lycopersicoides transcriptome, changes in gene expression were analyzed during pathogen infection. In response to B. cinerea, differentially expressed transcripts grouped into four categories: genes whose expression rapidly increased then rapidly decreased, genes whose expression rapidly increased and plateaued, genes whose expression continually increased, and genes with decreased expression. Homology-based searches also identified a limited number of highly expressed B. cinerea genes. Almost immediately after infection by B. cinerea, S. lycopersicoides suppressed photosynthesis and metabolic processes involved in growth, energy generation, and response to stimuli, and simultaneously induced various defense-related genes, including pathogenesis-related protein 1 (PR1), a beta-1,3-glucanase (glucanase), and a subtilisin-like protease, indicating a shift in priority towards defense. Moreover, cluster analysis revealed novel, uncharacterized genes that may play roles in defense against necrotrophic fungal pathogens in S. lycopersicoides. The expression of orthologous defense-related genes in S. lycopersicum after infection with B. cinerea revealed differences in the onset and intensity of induction, thus illuminating a potential mechanism explaining the increased susceptibility. Additionally, metabolic pathway analyses identified putative defense-related categories of secondary metabolites. CONCLUSIONS In sum, this study provided insight into resistance against necrotrophic fungal pathogens in the Solanaceae, as well as novel sequence resources for S. lycopersicoides.
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Affiliation(s)
- Jonathon E Smith
- />Department of Plant Pathology, University of Arkansas Division of Agriculture, 217 Plant Sciences, Fayetteville, AR 72701 USA
| | - Bemnet Mengesha
- />Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN USA
| | - Hua Tang
- />Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN USA
| | - Tesfaye Mengiste
- />Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN USA
| | - Burton H Bluhm
- />Department of Plant Pathology, University of Arkansas Division of Agriculture, 217 Plant Sciences, Fayetteville, AR 72701 USA
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Sardesai N, Laluk K, Mengiste T, Gelvin SB. The Arabidopsis Myb transcription factor MTF1 is a unidirectional regulator of susceptibility to Agrobacterium. Plant Signal Behav 2014; 9:28983. [PMID: 24785741 PMCID: PMC4091474 DOI: 10.4161/psb.28983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 04/23/2014] [Indexed: 05/28/2023]
Abstract
We recently described the Arabidopsis Myb transcription factor MTF1 that negatively regulates plant susceptibility to Agrobacterium-mediated transformation. Roots of mtf1 mutant plants show increased susceptibility to several Agrobacterium strains, and complementing the mutants with a MTF1 cDNA decreases transformation susceptibility to wild-type levels. Here, we show that overexpression of MTF1 in a wild-type Arabidopsis background does not result in altered transformation susceptibility. However, MTF1 overexpressing plants show increased root length and larger and darker leaves, indicating that MTF1 plays a role in plant growth and development. MTF1 decreases Arabidopsis root susceptibility specifically to Agrobacterium but plant responses to the pathogens Alternaria brassicicola or Pseudomonas syringae pv Tomato were not altered. However, the homozygous MTF1 mutant mtf1-4 is resistant to Botrytis cinerea strain BO5-10 and is regulated through the ethylene signaling pathway mediated by upregulation of the AP2/ERF transcription factor ORA59.
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Affiliation(s)
- Nagesh Sardesai
- Department of Biological Sciences; Purdue University; West Lafayette, IN USA
| | - Kristin Laluk
- Department of Botany and Plant Pathology; Purdue University; West Lafayette, IN USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology; Purdue University; West Lafayette, IN USA
| | - Stanton B Gelvin
- Department of Biological Sciences; Purdue University; West Lafayette, IN USA
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Sardesai N, Laluk K, Mengiste T, Gelvin SB. The Arabidopsis Myb transcription factor MTF1 is a unidirectional regulator of susceptibility to Agrobacterium. Plant Signal Behav 2014; 9:e28983. [PMID: 24785741 PMCID: PMC4091474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 04/23/2014] [Indexed: 02/28/2024]
Abstract
We recently described the Arabidopsis Myb transcription factor MTF1 that negatively regulates plant susceptibility to Agrobacterium-mediated transformation. Roots of mtf1 mutant plants show increased susceptibility to several Agrobacterium strains, and complementing the mutants with a MTF1 cDNA decreases transformation susceptibility to wild-type levels. Here, we show that overexpression of MTF1 in a wild-type Arabidopsis background does not result in altered transformation susceptibility. However, MTF1 overexpressing plants show increased root length and larger and darker leaves, indicating that MTF1 plays a role in plant growth and development. MTF1 decreases Arabidopsis root susceptibility specifically to Agrobacterium but plant responses to the pathogens Alternaria brassicicola or Pseudomonas syringae pv Tomato were not altered. However, the homozygous MTF1 mutant mtf1-4 is resistant to Botrytis cinerea strain BO5-10 and is regulated through the ethylene signaling pathway mediated by upregulation of the AP2/ERF transcription factor ORA59.
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Affiliation(s)
- Nagesh Sardesai
- Department of Biological Sciences; Purdue University; West Lafayette, IN USA
| | - Kristin Laluk
- Department of Botany and Plant Pathology; Purdue University; West Lafayette, IN USA
| | - Tesfaye Mengiste
- Department of Botany and Plant Pathology; Purdue University; West Lafayette, IN USA
| | - Stanton B Gelvin
- Department of Biological Sciences; Purdue University; West Lafayette, IN USA
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Lai Z, Mengiste T. Genetic and cellular mechanisms regulating plant responses to necrotrophic pathogens. Curr Opin Plant Biol 2013; 16:505-12. [PMID: 23859758 DOI: 10.1016/j.pbi.2013.06.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 06/14/2013] [Indexed: 05/04/2023]
Abstract
Necrotrophs are plant pathogens that kill host cells and proliferate on nutrients from dead or dying tissues causing devastating diseases of horticultural and agronomic crops. Their interactions with plants involve a complex network of pathogen disease factors and corresponding plant immune response regulators. Mechanisms of quantitative resistance and the major regulators intersect regardless of pathogen life style. By contrast, some plant immune responses, such as effector-triggered immunity (ETI), a major source of qualitative resistance to biotrophs, are co-opted by necrotrophs to promote disease, which highlights the disparate plant immunity systems. Advances towards understanding mechanisms and processes underlying host responses to necrotrophs are summarized.
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Affiliation(s)
- Zhibing Lai
- Purdue University, Department of Botany and Plant Pathology, 915 W. State Street, West Lafayette, IN 47907, United States
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Abstract
Insidious fungal infections by postharvest pathogens remain quiescent during fruit growth until, at a particular phase during fruit ripening and senescence, the pathogens switch to the necrotrophic lifestyle and cause decay. During ripening, fruits undergo physiological processes, such as activation of ethylene biosynthesis, cuticular changes, and cell-wall loosening-changes that are accompanied by a decline of antifungal compounds, both those that are preformed and those that are inducible secondary metabolites. Pathogen infection of the unripe host fruit initiates defensive signal-transduction cascades, culminating in accumulation of antifungal proteins that limit fungal growth and development. In contrast, development of the same pathogens during fruit ripening and storage activates a substantially different signaling network, one that facilitates aggressive fungal colonization. This review focuses on responses induced by the quiescent pathogens of postharvest diseases in unripe host fruits. New genome-scale experimental approaches have begun to delineate the complex and multiple networks of host and pathogen responses activated to maintain or to facilitate the transition from the quiescent to the necrotrophic lifestyle.
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Affiliation(s)
- Dov Prusky
- Department of Postharvest Science of Fresh Produce, ARO, Volcani Center, Bet Dagan, 50250 Israel.
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35
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Nambeesan S, AbuQamar S, Laluk K, Mattoo AK, Mickelbart MV, Ferruzzi MG, Mengiste T, Handa AK. Polyamines attenuate ethylene-mediated defense responses to abrogate resistance to Botrytis cinerea in tomato. Plant Physiol 2012; 158:1034-45. [PMID: 22128140 PMCID: PMC3271740 DOI: 10.1104/pp.111.188698] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 11/21/2011] [Indexed: 05/02/2023]
Abstract
Transgenic tomato (Solanum lycopersicum) lines overexpressing yeast spermidine synthase (ySpdSyn), an enzyme involved in polyamine (PA) biosynthesis, were developed. These transgenic lines accumulate higher levels of spermidine (Spd) than the wild-type plants and were examined for responses to the fungal necrotrophs Botrytis cinerea and Alternaria solani, bacterial pathogen Pseudomonas syringae pv tomato DC3000, and larvae of the chewing insect tobacco hornworm (Manduca sexta). The Spd-accumulating transgenic tomato lines were more susceptible to B. cinerea than the wild-type plants; however, responses to A. solani, P. syringae, or M. sexta were similar to the wild-type plants. Exogenous application of ethylene precursors, S-adenosyl-Met and 1-aminocyclopropane-1-carboxylic acid, or PA biosynthesis inhibitors reversed the response of the transgenic plants to B. cinerea. The increased susceptibility of the ySpdSyn transgenic tomato to B. cinerea was associated with down-regulation of gene transcripts involved in ethylene biosynthesis and signaling. These data suggest that PA-mediated susceptibility to B. cinerea is linked to interference with the functions of ethylene in plant defense.
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Affiliation(s)
| | | | | | | | | | | | | | - Avtar K. Handa
- Department of Horticulture and Landscape Architecture, Center for Plant Environmental Stress Physiology (S.N., M.V.M., A.K.H.), Department of Botany and Plant Pathology (K.L., T.M.), and Department of Food Science (M.G.F.), Purdue University, West Lafayette, Indiana 47907; Department of Biology, United Arab Emirates University, Al-Ain, Abu Dhabi, United Arab Emirates (S.A.); and Sustainable Agricultural Systems Laboratory, U.S. Department of Agriculture, Agricultural Research Service, The Henry A. Wallace Beltsville Agricultural Research Center, Beltsville, Maryland 20705 (A.K.M.)
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Abstract
Plants inhabit environments crowded with infectious microbes that pose constant threats to their survival. Necrotrophic pathogens are notorious for their aggressive and wide-ranging virulence strategies that promote host cell death and acquire nutrients for growth and reproduction from dead cells. This lifestyle constitutes the axis of their pathogenesis and virulence strategies and marks contrasting immune responses to biotrophic pathogens. The diversity of virulence strategies in necrotrophic species corresponds to multifaceted host immune response mechanisms. When effective, the plant immune system disarms the infectious necrotroph of its pathogenic arsenal or attenuates its effect, restricting further ingress and disease symptom development. Simply inherited resistance traits confer protection against host-specific necrotrophs (HSNs), whereas resistance to broad host-range necrotrophs (BHNs) is complex. Components of host genetic networks, as well as the molecular and cellular processes that mediate host immune responses to necrotrophs, are being identified. In this review, recent advances in our understanding of plant immune responses to necrotrophs and comparison with responses to biotrophic pathogens are summarized, highlighting common and contrasting mechanisms.
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Affiliation(s)
- Tesfaye Mengiste
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907, USA.
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37
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Laluk K, Mengiste T. The Arabidopsis extracellular UNUSUAL SERINE PROTEASE INHIBITOR functions in resistance to necrotrophic fungi and insect herbivory. Plant J 2011; 68:480-94. [PMID: 21749505 DOI: 10.1111/j.1365-313x.2011.04702.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Protease inhibitors (PIs) function in the precise regulation of proteases, and are thus involved in diverse biological processes in many organisms. Here, we studied the functions of the Arabidopsis UNUSUAL SERINE PROTEASE INHIBITOR (UPI) gene, which encodes an 8.8 kDa protein of atypical sequence relative to other PIs. Plants harboring a loss-of-function UPI allele displayed enhanced susceptibility to the necrotrophic fungi Botrytis cinerea and Alternaria brassicicola as well as the generalist herbivore Trichoplusia ni. Further, ectopic expression conferred increased resistance to B. cinerea and T. ni. In contrast, the mutant has wild-type responses to virulent, avirulent and non-pathogenic strains of Pseudomonas syringae, thus limiting the defense function of UPI to necrotrophic fungal infection and insect herbivory. Expression of UPI is significantly induced by jasmonate, salicylic acid and abscisic acid, but is repressed by ethylene, indicating complex phytohormone regulation of UPI expression. The upi mutant also shows significantly delayed flowering, associated with decreased SOC1 expression and elevated levels of MAF1, two regulators of floral transition. Recombinant UPI strongly inhibits the serine protease chymotrypsin but also weakly blocks the cysteine protease papain. Interestingly, jasmonate induces intra- and extracellular UPI accumulation, suggesting a possible role in intercellular or extracellular functions. Overall, our results show that UPI is a dual-specificity PI that functions in plant growth and defense, probably through the regulation of endogenous proteases and/or those of biotic invaders.
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Affiliation(s)
- Kristin Laluk
- Department of Botany and Plant Pathology, Purdue University, 915 W. State Street, West Lafayette, IN 47907, USA
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38
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Laluk K, AbuQamar S, Mengiste T. The Arabidopsis mitochondria-localized pentatricopeptide repeat protein PGN functions in defense against necrotrophic fungi and abiotic stress tolerance. Plant Physiol 2011; 156:2053-68. [PMID: 21653783 PMCID: PMC3149943 DOI: 10.1104/pp.111.177501] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Accepted: 06/07/2011] [Indexed: 05/18/2023]
Abstract
Pentatricopeptide repeat (PPR) proteins (PPRPs) are encoded by a large gene family in Arabidopsis (Arabidopsis thaliana), and their functions are largely unknown. The few studied PPRPs are implicated in different developmental processes through their function in RNA metabolism and posttranscriptional regulation in plant organelles. Here, we studied the functions of Arabidopsis PENTATRICOPEPTIDE REPEAT PROTEIN FOR GERMINATION ON NaCl (PGN) in plant defense and abiotic stress responses. Inactivation of PGN results in susceptibility to necrotrophic fungal pathogens as well as hypersensitivity to abscisic acid (ABA), glucose, and salinity. Interestingly, ectopic expression of PGN results in the same phenotypes as the pgn null allele, indicating that a tight regulation of the PGN transcript is required for normal function. Loss of PGN function dramatically enhanced reactive oxygen species accumulation in seedlings in response to salt stress. Inhibition of ABA synthesis and signaling partially alleviates the glucose sensitivity of pgn, suggesting that the mutant accumulates high endogenous ABA. Accordingly, induction of NCED3, encoding the rate-limiting enzyme in stress-induced ABA biosynthesis, is significantly higher in pgn, and the mutant has higher basal ABA levels, which may underlie its phenotypes. The pgn mutant has altered expression of other ABA-related genes as well as mitochondria-associated transcripts, most notably elevated levels of ABI4 and ALTERNATIVE OXIDASE1a, which are known for their roles in retrograde signaling induced by changes in or inhibition of mitochondrial function. These data, coupled with its mitochondrial localization, suggest that PGN functions in regulation of reactive oxygen species homeostasis in mitochondria during abiotic and biotic stress responses, likely through involvement in retrograde signaling.
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Laluk K, Luo H, Chai M, Dhawan R, Lai Z, Mengiste T. Biochemical and genetic requirements for function of the immune response regulator BOTRYTIS-INDUCED KINASE1 in plant growth, ethylene signaling, and PAMP-triggered immunity in Arabidopsis. Plant Cell 2011; 23:2831-49. [PMID: 21862710 PMCID: PMC3180795 DOI: 10.1105/tpc.111.087122] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/31/2011] [Accepted: 08/09/2011] [Indexed: 05/18/2023]
Abstract
Arabidopsis thaliana BOTRYTIS-INDUCED KINASE1 (BIK1) regulates immune responses to a distinct class of pathogens. Here, mechanisms underlying BIK1 function and its interactions with other immune response regulators were determined. We describe BIK1 function as a component of ethylene (ET) signaling and PAMP-triggered immunity (PTI) to fungal pathogens. BIK1 in vivo kinase activity increases in response to flagellin peptide (flg22) and the ET precursor 1-aminocyclopropane-1-carboxylic acid (ACC) but is blocked by inhibition of ET perception. BIK1 induction by flg22, ACC, and pathogens is strictly dependent on EIN3, and the bik1 mutation results in altered expression of ET-regulated genes. BIK1 site-directed mutants were used to determine residues essential for phosphorylation and biological functions in planta, including PTI, ET signaling, and plant growth. Genetic analysis revealed flg22-induced PTI to Botrytis cinerea requires BIK1, EIN2, and HUB1 but not genes involved in salicylate (SA) functions. BIK1-mediated PTI to Pseudomonas syringae is modulated by SA, ET, and jasmonate signaling. The coi1 mutation suppressed several bik1 phenotypes, suggesting that COI1 may act as a repressor of BIK1 function. Thus, common and distinct mechanisms underlying BIK1 function in mediating responses to distinct pathogens are uncovered. In sum, the critical role of BIK1 in plant immune responses hinges upon phosphorylation, its function in ET signaling, and complex interactions with other immune response regulators.
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Gutensohn M, Klempien A, Kaminaga Y, Nagegowda DA, Negre-Zakharov F, Huh JH, Luo H, Weizbauer R, Mengiste T, Tholl D, Dudareva N. Role of aromatic aldehyde synthase in wounding/herbivory response and flower scent production in different Arabidopsis ecotypes. Plant J 2011; 66:591-602. [PMID: 21284755 DOI: 10.1111/j.1365-313x.2011.04515.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Aromatic L-amino acid decarboxylases (AADCs) are key enzymes operating at the interface between primary and secondary metabolism. The Arabidopsis thaliana genome contains two genes, At2g20340 and At4g28680, encoding pyridoxal 5'-phosphate-dependent AADCs with high homology to the recently identified Petunia hybrida phenylacetaldehyde synthase involved in floral scent production. The At4g28680 gene product was recently biochemically characterized as an L-tyrosine decarboxylase (AtTYDC), whereas the function of the other gene product remains unknown. The biochemical and functional characterization of the At2g20340 gene product revealed that it is an aromatic aldehyde synthase (AtAAS), which catalyzes the conversion of phenylalanine and 3,4-dihydroxy-L-phenylalanine to phenylacetaldehyde and dopaldehyde, respectively. AtAAS knock-down and transgenic AtAAS RNA interference (RNAi) lines show significant reduction in phenylacetaldehyde levels and an increase in phenylalanine, indicating that AtAAS is responsible for phenylacetaldehyde formation in planta. In A. thaliana ecotype Columbia (Col-0), AtAAS expression was highest in leaves, and was induced by methyl jasmonate treatment and wounding. Pieris rapae larvae feeding on Col-0 leaves resulted in increased phenylacetaldehyde emission, suggesting that the emitted aldehyde has a defensive activity against attacking herbivores. In the ecotypes Sei-0 and Di-G, which emit phenylacetaldehyde as a predominant flower volatile, the highest expression of AtAAS was found in flowers and RNAi AtAAS silencing led to a reduction of phenylacetaldehyde formation in this organ. In contrast to ecotype Col-0, no phenylacetaldehyde accumulation was observed in Sei-0 upon wounding, suggesting that AtAAS and subsequently phenylacetaldehyde contribute to pollinator attraction in this ecotype.
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Affiliation(s)
- Michael Gutensohn
- Department of Horticulture and Landscape Architecture, Purdue University, 625 Agriculture Mall Drive, West Lafayette, IN 47907, USA
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Luo H, Laluk K, Lai Z, Veronese P, Song F, Mengiste T. The Arabidopsis Botrytis Susceptible1 Interactor defines a subclass of RING E3 ligases that regulate pathogen and stress responses. Plant Physiol 2010; 154:1766-82. [PMID: 20921156 PMCID: PMC2996010 DOI: 10.1104/pp.110.163915] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Accepted: 09/30/2010] [Indexed: 05/18/2023]
Abstract
We studied the function of Arabidopsis (Arabidopsis thaliana) Botrytis Susceptible1 Interactor (BOI) in plant responses to pathogen infection and abiotic stress. BOI physically interacts with and ubiquitinates Arabidopsis BOS1, an R2R3MYB transcription factor previously implicated in stress and pathogen responses. In transgenic plants expressing the BOS1-β-glucuronidase transgene, β-glucuronidase activity could be detected only after inhibition of the proteosome, suggesting that BOS1 is a target of ubiquitin-mediated degradation by the proteosome. Plants with reduced BOI transcript levels generated through RNA interference (BOI RNAi) were more susceptible to the necrotrophic fungus Botrytis cinerea and less tolerant to salt stress. In addition, BOI RNAi plants exhibited increased cell death induced by the phytotoxin α-picolinic acid and by a virulent strain of the bacterial pathogen Pseudomonas syringae, coincident with peak disease symptoms. However, the hypersensitive cell death associated with different race-specific resistance genes was unaffected by changes in the level of BOI transcript. BOI expression was enhanced by B. cinerea and salt stress but repressed by the plant hormone gibberellin, indicating a complex regulation of BOI gene expression. Interestingly, BOI RNAi plants exhibit reduced growth responsiveness to gibberellin. We also present data revealing the function of three Arabidopsis BOI-RELATED GENES (BRGs), which contribute to B. cinerea resistance and the suppression of disease-associated cell death. In sum, BOI and BRGs represent a subclass of RING E3 ligases that contribute to plant disease resistance and abiotic stress tolerance through the suppression of pathogen-induced as well as stress-induced cell death.
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Abstract
Necrotrophic pathogens cause major pre- and post-harvest diseases in numerous agronomic and horticultural crops inflicting significant economic losses. In contrast to biotrophs, obligate plant parasites that infect and feed on living cells, necrotrophs promote the destruction of host cells to feed on their contents. This difference underpins the divergent pathogenesis strategies and plant immune responses to biotrophic and necrotrophic infections. This chapter focuses on Arabidopsis immunity to necrotrophic pathogens. The strategies of infection, virulence and suppression of host defenses recruited by necrotrophs and the variation in host resistance mechanisms are highlighted. The multiplicity of intraspecific virulence factors and species diversity in necrotrophic organisms corresponds to variations in host resistance strategies. Resistance to host-specific necrotophs is monogenic whereas defense against broad host necrotrophs is complex, requiring the involvement of many genes and pathways for full resistance. Mechanisms and components of immunity such as the role of plant hormones, secondary metabolites, and pathogenesis proteins are presented. We will discuss the current state of knowledge of Arabidopsis immune responses to necrotrophic pathogens, the interactions of these responses with other defense pathways, and contemplate on the directions of future research.
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Affiliation(s)
- Kristin Laluk
- Purdue University, Department of Botany and Plant Pathology, 915 W. State Street, West Lafayette, IN 47907
- Address correspondence to
and
| | - Tesfaye Mengiste
- Purdue University, Department of Botany and Plant Pathology, 915 W. State Street, West Lafayette, IN 47907
- Address correspondence to
and
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Wang X, Basnayake BMVS, Zhang H, Li G, Li W, Virk N, Mengiste T, Song F. The Arabidopsis ATAF1, a NAC transcription factor, is a negative regulator of defense responses against necrotrophic fungal and bacterial pathogens. Mol Plant Microbe Interact 2009; 22:1227-1238. [PMID: 19737096 DOI: 10.1016/j.ppnp.2008.12.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Transcription factors of the NAC family are known to be involved in various growth or developmental processes and in regulation of response to environmental stresses. In the present study, we report that Arabidopsis ATAF1 is a negative regulator of defense responses against both necrotrophic fungal and bacterial pathogens. Expression of ATAF1 was downregulated after infection with Botrytis cinerea or Pseudomonas syringae pv. tomato or after treatment with salicylic acid (SA), jasmonic acid, and 1-amino cyclopropane-1-carboxylic acid (the precursor of ethylene biosynthesis). Transgenic plants that overexpress the ATAF1 gene (ATAF1-OE) showed increased susceptibility while expression of an ATAF1 chimeric repressor construct (ATAF1-SRDX) exhibited enhanced resistance to P. syringae pv. tomato DC3000, B. cinerea, and Alternaria brassicicola. The ataf1 mutant plants showed no significant resistance against the pathogens tested. After inoculation with B. cinerea or P. syringae pv. tomato DC3000, expressions of defense-related genes PR-1, PR-5. and PDF1.2 were upregulated in the ATAF1-SRDX plants but attenuated or unchanged in the ATAF1-OE plants. In ATAF1-OE plants, SA-induced expression of pathogenesis-related genes and disease resistance against P. syringae pv. tomato DC3000 was partially suppressed. Increased levels of reactive oxygen species (i.e., H(2)O(2) and superoxide anion) accumulated only in the ATAF1-OE but not in the ATAF1-SRDX plants after Botrytis spp. infection. Our studies provide direct genetic evidence for the role of ATAF1 as a negative regulator of defense response against different type of pathogens.
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Affiliation(s)
- Xiao'e Wang
- State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University-Huajiachi Campus, Hangzhou, Zhejiang 310029, People's Republic of China
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Wang X, Basnayake BMVS, Zhang H, Li G, Li W, Virk N, Mengiste T, Song F. The Arabidopsis ATAF1, a NAC transcription factor, is a negative regulator of defense responses against necrotrophic fungal and bacterial pathogens. Mol Plant Microbe Interact 2009; 22:1227-38. [PMID: 19737096 DOI: 10.1094/mpmi-22-10-1227] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Transcription factors of the NAC family are known to be involved in various growth or developmental processes and in regulation of response to environmental stresses. In the present study, we report that Arabidopsis ATAF1 is a negative regulator of defense responses against both necrotrophic fungal and bacterial pathogens. Expression of ATAF1 was downregulated after infection with Botrytis cinerea or Pseudomonas syringae pv. tomato or after treatment with salicylic acid (SA), jasmonic acid, and 1-amino cyclopropane-1-carboxylic acid (the precursor of ethylene biosynthesis). Transgenic plants that overexpress the ATAF1 gene (ATAF1-OE) showed increased susceptibility while expression of an ATAF1 chimeric repressor construct (ATAF1-SRDX) exhibited enhanced resistance to P. syringae pv. tomato DC3000, B. cinerea, and Alternaria brassicicola. The ataf1 mutant plants showed no significant resistance against the pathogens tested. After inoculation with B. cinerea or P. syringae pv. tomato DC3000, expressions of defense-related genes PR-1, PR-5. and PDF1.2 were upregulated in the ATAF1-SRDX plants but attenuated or unchanged in the ATAF1-OE plants. In ATAF1-OE plants, SA-induced expression of pathogenesis-related genes and disease resistance against P. syringae pv. tomato DC3000 was partially suppressed. Increased levels of reactive oxygen species (i.e., H(2)O(2) and superoxide anion) accumulated only in the ATAF1-OE but not in the ATAF1-SRDX plants after Botrytis spp. infection. Our studies provide direct genetic evidence for the role of ATAF1 as a negative regulator of defense response against different type of pathogens.
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Affiliation(s)
- Xiao'e Wang
- State Key Laboratory for Rice Biology, Institute of Biotechnology, Zhejiang University-Huajiachi Campus, Hangzhou, Zhejiang 310029, People's Republic of China
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Mang HG, Laluk KA, Parsons EP, Kosma DK, Cooper BR, Park HC, AbuQamar S, Boccongelli C, Miyazaki S, Consiglio F, Chilosi G, Bohnert HJ, Bressan RA, Mengiste T, Jenks MA. The Arabidopsis RESURRECTION1 gene regulates a novel antagonistic interaction in plant defense to biotrophs and necrotrophs. Plant Physiol 2009; 151:290-305. [PMID: 19625635 PMCID: PMC2735982 DOI: 10.1104/pp.109.142158] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 07/17/2009] [Indexed: 05/18/2023]
Abstract
We report a role for the Arabidopsis (Arabidopsis thaliana) RESURRECTION1 (RST1) gene in plant defense. The rst1 mutant exhibits enhanced susceptibility to the biotrophic fungal pathogen Erysiphe cichoracearum but enhanced resistance to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola. RST1 encodes a novel protein that localizes to the plasma membrane and is predicted to contain 11 transmembrane domains. Disease responses in rst1 correlate with higher levels of jasmonic acid (JA) and increased basal and B. cinerea-induced expression of the plant defensin PDF1.2 gene but reduced E. cichoracearum-inducible salicylic acid levels and expression of pathogenesis-related genes PR1 and PR2. These results are consistent with rst1's varied resistance and susceptibility to pathogens of different life styles. Cuticular lipids, both cutin monomers and cuticular waxes, on rst1 leaves were significantly elevated, indicating a role for RST1 in the suppression of leaf cuticle lipid synthesis. The rst1 cuticle exhibits normal permeability, however, indicating that the disease responses of rst1 are not due to changes in this cuticle property. Double mutant analysis revealed that the coi1 mutation (causing defective JA signaling) is completely epistatic to rst1, whereas the ein2 mutation (causing defective ethylene signaling) is partially epistatic to rst1, for resistance to B. cinerea. The rst1 mutation thus defines a unique combination of disease responses to biotrophic and necrotrophic fungi in that it antagonizes salicylic acid-dependent defense and enhances JA-mediated defense through a mechanism that also controls cuticle synthesis.
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Affiliation(s)
- Hyung Gon Mang
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana 47907-2054, USA
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Abuqamar S, Luo H, Laluk K, Mickelbart MV, Mengiste T. Crosstalk between biotic and abiotic stress responses in tomato is mediated by the AIM1 transcription factor. Plant J 2009; 58:347-60. [PMID: 19143995 DOI: 10.1111/j.1365-313x.2008.03783.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Plants deploy diverse molecular and cellular mechanisms to survive in stressful environments. The tomato (Solanum lycopersicum) abscisic acid-induced myb1 (SlAIM1) gene encoding an R2R3MYB transcription factor is induced by pathogens, plant hormones, salinity and oxidative stress, suggesting a function in pathogen and abiotic stress responses. Tomato SlAIM1 RNA interference (RNAi) plants with reduced SlAIM1 gene expression show an increased susceptibility to the necrotrophic fungus Botrytis cinerea, and increased sensitivity to salt and oxidative stress. Ectopic expression of SlAIM1 is sufficient for tolerance to high salinity and oxidative stress. These responses correlate with reduced sensitivity to abscisic acid (ABA) in the SlAIM1 RNAi, but increased sensitivity in the overexpression plants, suggesting SlAIM1-mediated ABA responses are required to integrate tomato responses to biotic and abiotic stresses. Interestingly, when exposed to high root-zone salinity levels, SlAIM1 RNAi plants accumulate more Na(+), whereas the overexpression lines accumulate less Na(+) relative to wild-type plants, suggesting that SlAIM1 regulates ion fluxes. Transmembrane ion flux is a hallmark of early responses to abiotic stress and pathogen infection preceding hypersensitive cell death and necrosis. Misregulation of ion fluxes can result in impaired plant tolerance to necrotrophic infection or abiotic stress. Our data reveal a previously uncharacterized connection between ABA, Na(+) homeostasis, oxidative stress and pathogen response, and shed light on the genetic control of crosstalk between plant responses to pathogens and abiotic stress. Together, our data suggest SlAIM1 integrates plant responses to pathogens and abiotic stresses by modulating responses to ABA.
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Affiliation(s)
- Synan Abuqamar
- Department of Botany and Plant Pathology, Purdue University, 915 West state street, West Lafayette, IN 47907-2054, USA
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Dhawan R, Luo H, Foerster AM, Abuqamar S, Du HN, Briggs SD, Mittelsten Scheid O, Mengiste T. HISTONE MONOUBIQUITINATION1 interacts with a subunit of the mediator complex and regulates defense against necrotrophic fungal pathogens in Arabidopsis. Plant Cell 2009; 21:1000-19. [PMID: 19286969 PMCID: PMC2671699 DOI: 10.1105/tpc.108.062364] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 02/11/2009] [Accepted: 02/26/2009] [Indexed: 05/17/2023]
Abstract
This work examines the role of the Arabidopsis thaliana RING E3 ligase, HISTONE MONOUBIQUITINATION1 (HUB1) in disease resistance. Loss-of-function alleles of HUB1 show increased susceptibility to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola, whereas HUB1 overexpression conferred resistance to B. cinerea. By contrast, responses to the bacterial pathogen Pseudomonas syringae are unaltered in hub1 plants. hub1 mutants have thinner cell walls but increased callose around an infection site. HUB1 acts independently of jasmonate, but ethylene (ET) responses and salicylate modulate the resistance of hub1 mutants to necrotrophic fungi. The ET response factor ETHYLENE INSENSITIVE2 is epistatic to HUB1 for A. brassicicola resistance but additive to HUB1 for B. cinerea resistance. HUB1 interacts with MED21, a subunit of the Arabidopsis Mediator, a conserved complex that regulates RNA polymerase II. RNA interference lines with reduced MED21 expression are highly susceptible to A. brassicicola and B. cinerea, whereas T-DNA insertion alleles are embryonic lethal, suggesting an essential role for MED21. However, HUB1-mediated histone H2B modification is independent of histone H3 and DNA methylation. In sum, histone H2B monoubiquitination is an important chromatin modification with regulatory roles in plant defense against necrotrophic fungi most likely through modulation of gene expression.
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Affiliation(s)
- Rahul Dhawan
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907-2054, USA
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Dhawan R, Luo H, Foerster AM, Abuqamar S, Du HN, Briggs SD, Mittelsten Scheid O, Mengiste T. HISTONE MONOUBIQUITINATION1 interacts with a subunit of the mediator complex and regulates defense against necrotrophic fungal pathogens in Arabidopsis. Plant Cell 2009. [PMID: 19286969 DOI: 10.2307/40537446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
This work examines the role of the Arabidopsis thaliana RING E3 ligase, HISTONE MONOUBIQUITINATION1 (HUB1) in disease resistance. Loss-of-function alleles of HUB1 show increased susceptibility to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola, whereas HUB1 overexpression conferred resistance to B. cinerea. By contrast, responses to the bacterial pathogen Pseudomonas syringae are unaltered in hub1 plants. hub1 mutants have thinner cell walls but increased callose around an infection site. HUB1 acts independently of jasmonate, but ethylene (ET) responses and salicylate modulate the resistance of hub1 mutants to necrotrophic fungi. The ET response factor ETHYLENE INSENSITIVE2 is epistatic to HUB1 for A. brassicicola resistance but additive to HUB1 for B. cinerea resistance. HUB1 interacts with MED21, a subunit of the Arabidopsis Mediator, a conserved complex that regulates RNA polymerase II. RNA interference lines with reduced MED21 expression are highly susceptible to A. brassicicola and B. cinerea, whereas T-DNA insertion alleles are embryonic lethal, suggesting an essential role for MED21. However, HUB1-mediated histone H2B modification is independent of histone H3 and DNA methylation. In sum, histone H2B monoubiquitination is an important chromatin modification with regulatory roles in plant defense against necrotrophic fungi most likely through modulation of gene expression.
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Affiliation(s)
- Rahul Dhawan
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907-2054, USA
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Abuqamar S, Chai MF, Luo H, Song F, Mengiste T. Tomato protein kinase 1b mediates signaling of plant responses to necrotrophic fungi and insect herbivory. Plant Cell 2008; 20:1964-83. [PMID: 18599583 PMCID: PMC2518242 DOI: 10.1105/tpc.108.059477] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 06/11/2008] [Accepted: 06/16/2008] [Indexed: 05/18/2023]
Abstract
The tomato protein kinase 1 (TPK1b) gene encodes a receptor-like cytoplasmic kinase localized to the plasma membrane. Pathogen infection, mechanical wounding, and oxidative stress induce expression of TPK1b, and reducing TPK1b gene expression through RNA interference (RNAi) increases tomato susceptibility to the necrotrophic fungus Botrytis cinerea and to feeding by larvae of tobacco hornworm (Manduca sexta) but not to the bacterial pathogen Pseudomonas syringae. TPK1b RNAi seedlings are also impaired in ethylene (ET) responses. Notably, susceptibility to Botrytis and insect feeding is correlated with reduced expression of the proteinase inhibitor II gene in response to Botrytis and 1-aminocyclopropane-1-carboxylic acid, the natural precursor of ET, but wild-type expression in response to mechanical wounding and methyl-jasmonate. TPK1b functions independent of JA biosynthesis and response genes required for resistance to Botrytis. TPK1b is a functional kinase with autophosphorylation and Myelin Basis Protein phosphorylation activities. Three residues in the activation segment play a critical role in the kinase activity and in vivo signaling function of TPK1b. In sum, our findings establish a signaling role for TPK1b in an ET-mediated shared defense mechanism for resistance to necrotrophic fungi and herbivorous insects.
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Affiliation(s)
- Synan Abuqamar
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907-2054, USA
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Kemmerling B, Schwedt A, Rodriguez P, Mazzotta S, Frank M, Qamar SA, Mengiste T, Betsuyaku S, Parker JE, Müssig C, Thomma BPHJ, Albrecht C, de Vries SC, Hirt H, Nürnberger T. The BRI1-Associated Kinase 1, BAK1, Has a Brassinolide-Independent Role in Plant Cell-Death Control. Curr Biol 2007; 17:1116-22. [PMID: 17583510 DOI: 10.1016/j.cub.2007.05.046] [Citation(s) in RCA: 247] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Revised: 05/16/2007] [Accepted: 05/17/2007] [Indexed: 10/23/2022]
Abstract
Programmed cell death (PCD) is a common host response to microbial infection [1-3]. In plants, PCD is associated with immunity to biotrophic pathogens, but it can also promote disease upon infection by necrotrophic pathogens [4]. Therefore, plant cell-suicide programs must be strictly controlled. Here we demonstrate that the Arabidopsis thaliana Brassinosteroid Insensitive 1 (BRI1)-associated receptor Kinase 1 (BAK1), which operates as a coreceptor of BRI1 in brassinolide (BL)-dependent plant development, also regulates the containment of microbial infection-induced cell death. BAK1-deficient plants develop spreading necrosis upon infection. This is accompanied by production of reactive oxygen intermediates and results in enhanced susceptibility to necrotrophic fungal pathogens. The exogenous application of BL rescues growth defects of bak1 mutants but fails to restore immunity to fungal infection. Moreover, BL-insensitive and -deficient mutants do not exhibit spreading necrosis or enhanced susceptibility to fungal infections. Together, these findings suggest that plant steroid-hormone signaling is dispensable for the containment of infection-induced PCD. We propose a novel, BL-independent function of BAK1 in plant cell-death control that is distinct from its BL-dependent role in plant development.
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Affiliation(s)
- Birgit Kemmerling
- Department of Plant Biochemistry, Center for Plant Molecular Biology, Eberhard-Karls-University Tübingen, Tübingen, Germany
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