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Zhang S, Wang X, Zhao T, Zhou C. Effector CLas0185 targets methionine sulphoxide reductase B1 of Citrus sinensis to promote multiplication of 'Candidatus Liberibacter asiaticus' via enhancing enzymatic activity of ascorbate peroxidase 1. MOLECULAR PLANT PATHOLOGY 2024; 25:e70002. [PMID: 39215961 PMCID: PMC11365454 DOI: 10.1111/mpp.70002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 07/17/2024] [Accepted: 08/12/2024] [Indexed: 09/04/2024]
Abstract
Citrus huanglongbing (HLB) has been causing enormous damage to the global citrus industry. As the main causal agent, 'Candidatus Liberibacter asiaticus' (CLas) delivers a set of effectors to modulate host responses, while the modes of action adopted remain largely unclear. Here, we demonstrated that CLIBASIA_00185 (CLas0185) could attenuate reactive oxygen species (ROS)-mediated cell death in Nicotiana benthamiana. Transgenic expression of CLas0185 in Citrus sinensis 'Wanjincheng' enhanced plant susceptibility to CLas. We found that methionine sulphoxide reductase B1 (CsMsrB1) was targeted by the effector, and its abundance was elevated in CLas0185-transgenic citrus plants. Their interaction promoted CLas proliferation. We then determined that CsMsrB1 sustained redox state and enzymatic activity of ascorbate peroxidase 1 (CsAPX1) under oxidative stress. The latter reduced H2O2 accumulation and was associated with host susceptibility to CLas infection. Consistently, citrus plants expressing CLas0185 and CsMsrB1 conferred enhanced APX activity and decreased H2O2 content. Taken together, these findings revealed how CLas0185 benefits CLas colonization by targeting CsMsrB1, which facilitated the antioxidant activity and depressed ROS during pathogen infection.
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Affiliation(s)
- Shushe Zhang
- Citrus Research InstituteSouthwest University, National Citrus Engineering Research CenterChongqingChina
- State Key Laboratory for Biology of Plant Diseases and Insect PestsChinese Academy of Agriculture Sciences, Institute of Plant ProtectionBeijingChina
| | - Xuefeng Wang
- Citrus Research InstituteSouthwest University, National Citrus Engineering Research CenterChongqingChina
| | - Tingchang Zhao
- State Key Laboratory for Biology of Plant Diseases and Insect PestsChinese Academy of Agriculture Sciences, Institute of Plant ProtectionBeijingChina
| | - Changyong Zhou
- Citrus Research InstituteSouthwest University, National Citrus Engineering Research CenterChongqingChina
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Zhu L, Chen L, Wu C, Shan W, Cai D, Lin Z, Wei W, Chen J, Lu W, Kuang J. Methionine oxidation and reduction of the ethylene signaling component MaEIL9 are involved in banana fruit ripening. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2023; 65:150-166. [PMID: 36103229 DOI: 10.1111/jipb.13363] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
The ethylene insensitive 3/ethylene insensitive 3-like (EIN3/EIL) plays an indispensable role in fruit ripening. However, the regulatory mechanism that links post-translational modification of EIN3/EIL to fruit ripening is largely unknown. Here, we studied the expression of 13 MaEIL genes during banana fruit ripening, among which MaEIL9 displayed higher enhancement particularly in the ripening stage. Consistent with its transcript pattern, abundance of MaEIL9 protein gradually increased during the ripening process, with maximal enhancement in the ripening. DNA affinity purification (DAP)-seq analysis revealed that MaEIL9 directly targets a subset of genes related to fruit ripening, such as the starch hydrolytic genes MaAMY3D and MaBAM1. Stably overexpressing MaEIL9 in tomato fruit hastened fruit ripening, whereas transiently silencing this gene in banana fruit retarded the ripening process, supporting a positive role of MaEIL9 in fruit ripening. Moreover, oxidation of methionines (Met-129, Met-130, and Met-282) in MaEIL9 resulted in the loss of its DNA-binding capacity and transcriptional activation activity. Importantly, we identified MaEIL9 as a potential substrate protein of methionine sulfoxide reductase A MaMsrA4, and oxidation of Met-129, Met-130, and Met-282 in MaEIL9 could be restored by MaMsrA4. Collectively, our findings reveal a novel regulatory network controlling banana fruit ripening, which involves MaMsrA4-mediated redox regulation of the ethylene signaling component MaEIL9.
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Affiliation(s)
- Lisha Zhu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Lin Chen
- Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (South China), Ministry of Agriculture and Rural Affairs, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Chaojie Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Wei Shan
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Danling Cai
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Zengxiang Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Wei Wei
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Jianye Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Wangjin Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
| | - Jianfei Kuang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources/Guangdong Provincial Key Laboratory of Postharvest Science of Fruits and Vegetables/Engineering Research Center of Southern Horticultural Products Preservation, Ministry of Education, College of Horticulture, South China Agricultural University, Guangzhou, 510642, China
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Si Z, Guan N, Zhou Y, Mei L, Li Y, Li Y. A Methionine Sulfoxide Reductase B Is Required for the Establishment of Astragalus sinicus-Mesorhizobium Symbiosis. PLANT & CELL PHYSIOLOGY 2020; 61:1631-1645. [PMID: 32618998 DOI: 10.1093/pcp/pcaa085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Methionine sulfoxide reductase B (MsrB) is involved in oxidative stress or defense responses in plants. However, little is known about its role in legume-rhizobium symbiosis. In this study, an MsrB gene was identified from Astragalus sinicus and its function in symbiosis was characterized. AsMsrB was induced under phosphorus starvation and displayed different expression patterns under symbiotic and nonsymbiotic conditions. Hydrogen peroxide or methyl viologen treatment enhanced the transcript level of AsMsrB in roots and nodules. Subcellular localization showed that AsMsrB was localized in the cytoplasm of onion epidermal cells and co-localized with rhizobia in nodules. Plants with AsMsrB-RNAi hairy roots exhibited significant decreases in nodule number, nodule nitrogenase activity and fresh weight of the aerial part, as well as an abnormal nodule and symbiosome development. Statistical analysis of infection events showed that plants with AsMsrB-RNAi hairy roots had significant decreases in the number of root hair curling events, infection threads and nodule primordia compared with the control. The content of hydrogen peroxide increased in AsMsrB-RNAi roots but decreased in AsMsrB overexpression roots at the early stage of infection. The transcriptome analysis showed synergistic modulations of the expression of genes involved in reactive oxygen species generation and scavenging, defense and pathogenesis and early nodulation. In addition, a candidate protein interacting with AsMsrB was identified and confirmed by bimolecular fluorescence complementation. Taken together, our results indicate that AsMsrB plays an essential role in nodule development and symbiotic nitrogen fixation by affecting the redox homeostasis in roots and nodules.
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Affiliation(s)
- Zaiyong Si
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Ning Guan
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yuan Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Lingli Mei
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yixing Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Youguo Li
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
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Ding P, Fang L, Wang G, Li X, Huang S, Gao Y, Zhu J, Xiao L, Tong J, Chen F, Xia G. Wheat methionine sulfoxide reductase A4.1 interacts with heme oxygenase 1 to enhance seedling tolerance to salinity or drought stress. PLANT MOLECULAR BIOLOGY 2019; 101:203-220. [PMID: 31297725 DOI: 10.1007/s11103-019-00901-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 07/04/2019] [Indexed: 06/10/2023]
Abstract
Here, a functional characterization of a wheat MSR has been presented: this protein makes a contribution to the plant's tolerance of abiotic stress, acting through its catalytic capacity and its modulation of ROS and ABA pathways. The molecular mechanism and function of certain members of the methionine sulfoxide reductase (MSR) gene family have been defined, however, these analyses have not included the wheat equivalents. The wheat MSR gene TaMSRA4.1 is inducible by salinity and drought stress and in this study, we demonstrate that its activity is restricted to the Met-S-SO enantiomer, and its subcellular localization is in the chloroplast. Furthermore, constitutive expression of TaMSRA4.1 enhanced the salinity and drought tolerance of wheat and Arabidopsis thaliana. In these plants constitutively expressing TaMSRA4.1, the accumulation of reactive oxygen species (ROS) was found to be influenced through the modulation of genes encoding proteins involved in ROS signaling, generation and scavenging, while the level of endogenous abscisic acid (ABA), and the sensitivity of stomatal guard cells to exogenous ABA, was increased. A yeast two-hybrid screen, bimolecular fluorescence complementation and co-immunoprecipitation assays demonstrated that heme oxygenase 1 (HO1) interacted with TaMSRA4.1, and that this interaction depended on a TaHO1 C-terminal domain. In plants subjected to salinity or drought stress, TaMSRA4.1 reversed the oxidation of TaHO1, activating ROS and ABA signaling pathways, but not in the absence of HO1. The aforementioned properties advocate TaMSRA4.1 as a candidate for plant genetic enhancement.
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Affiliation(s)
- Pengcheng Ding
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Linlin Fang
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Guangling Wang
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Xiang Li
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Shu Huang
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Yankun Gao
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Jiantang Zhu
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Langtao Xiao
- Hunan Provincial Key Laboratory of Phytohormones, Southern Regional Collaborative Innovation Center for Grain and Oil Crops, Hunan Agricultural University, Changsha, 410128, China
| | - Jianhua Tong
- Hunan Provincial Key Laboratory of Phytohormones, Southern Regional Collaborative Innovation Center for Grain and Oil Crops, Hunan Agricultural University, Changsha, 410128, China
| | - Fanguo Chen
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China.
| | - Guangmin Xia
- The Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
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Le DT, Nguyen KL, Chu HD, Vu NT, Pham TTL, Tran LSP. Function of the evolutionarily conserved plant methionine-S-sulfoxide reductase without the catalytic residue. PROTOPLASMA 2018; 255:1741-1750. [PMID: 29808313 DOI: 10.1007/s00709-018-1266-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 05/15/2018] [Indexed: 06/08/2023]
Abstract
In plants, two types of methionine sulfoxide reductase (MSR) exist, namely methionine-S-sulfoxide reductase (MSRA) and methionine-R-sulfoxide reductase (MSRB). These enzymes catalyze the reduction of methionine sulfoxides (MetO) back to methionine (Met) by a catalytic cysteine (Cys) and one or two resolving Cys residues. Interestingly, a group of MSRA encoded by plant genomes does not have a catalytic residue. We asked that if this group of MSRA did not have any function (as fitness), why it was not lost during the evolutionary process. To challenge this question, we analyzed the gene family encoding MSRA in soybean (GmMSRAs). We found seven genes encoding GmMSRAs, which included three segmental duplicated pairs. Among them, a pair of duplicated genes, namely GmMSRA1 and GmMSRA6, was without a catalytic Cys residue. Pseudogenes were ruled out as their transcripts were detected in various tissues and their Ka/Ks ratio indicated a negative selection pressure. In vivo analysis in Δ3MSR yeast strain indicated that the GmMSRA6 did not have activity toward MetO, contrasting to GmMSRA3 which had catalytic Cys and had activity. When exposed to H2O2-induced oxidative stress, GmMSRA6 did not confer any protection to the Δ3MSR yeast strain. Overexpression of GmMSRA6 in Arabidopsis thaliana did not alter the plant's phenotype under physiological conditions. However, the transgenic plants exhibited slightly higher sensitivity toward salinity-induced stress. Taken together, this data suggested that the plant MSRAs without the catalytic Cys are not enzymatically active and their existence may be explained by a role in regulating plant MSR activity via dominant-negative substrate competition mechanism.
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Affiliation(s)
- Dung Tien Le
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Street, Hanoi, Vietnam.
- DEKALB Viet Nam Company Limited (a Monsanto Company), Ho Chi Minh City, Viet Nam.
| | - Kim-Lien Nguyen
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Street, Hanoi, Vietnam
| | - Ha Duc Chu
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Street, Hanoi, Vietnam
| | - Nam Tuan Vu
- The Metabolic Network Biology Laboratory, Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Thu Thi Ly Pham
- Agricultural Genetics Institute, Vietnam Academy of Agricultural Sciences, Pham Van Dong Street, Hanoi, Vietnam
| | - Lam-Son Phan Tran
- Stress Adaptation Research Unit, RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, 230-0045, Japan.
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Physiological Roles of Plant Methionine Sulfoxide Reductases in Redox Homeostasis and Signaling. Antioxidants (Basel) 2018; 7:antiox7090114. [PMID: 30158486 PMCID: PMC6162775 DOI: 10.3390/antiox7090114] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/24/2018] [Accepted: 08/26/2018] [Indexed: 01/09/2023] Open
Abstract
Oxidation of methionine (Met) leads to the formation of two S- and R-diastereoisomers of Met sulfoxide (MetO) that are reduced back to Met by methionine sulfoxide reductases (MSRs), A and B, respectively. Here, we review the current knowledge about the physiological functions of plant MSRs in relation with subcellular and tissue distribution, expression patterns, mutant phenotypes, and possible targets. The data gained from modified lines of plant models and crop species indicate that MSRs play protective roles upon abiotic and biotic environmental constraints. They also participate in the control of the ageing process, as shown in seeds subjected to adverse conditions. Significant advances were achieved towards understanding how MSRs could fulfil these functions via the identification of partners among Met-rich or MetO-containing proteins, notably by using redox proteomic approaches. In addition to a global protective role against oxidative damage in proteins, plant MSRs could specifically preserve the activity of stress responsive effectors such as glutathione-S-transferases and chaperones. Moreover, several lines of evidence indicate that MSRs fulfil key signaling roles via interplays with Ca2+- and phosphorylation-dependent cascades, thus transmitting ROS-related information in transduction pathways.
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Dong B, Wu B, Hong W, Li X, Li Z, Xue L, Huang Y. Transcriptome analysis of the tea oil camellia (Camellia oleifera) reveals candidate drought stress genes. PLoS One 2017; 12:e0181835. [PMID: 28759610 PMCID: PMC5536306 DOI: 10.1371/journal.pone.0181835] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 07/08/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The tea-oil camellia (Camellia oleifera) is the most important oil plant in southern China, and has a strong resistance to drought and barren soil. Understanding the molecular mechanisms of drought tolerance would greatly promote its cultivation and molecular breeding. RESULTS In total, we obtained 76,585 unigenes with an average length of 810 bp and an N50 of 1,092 bp. We mapped all the unigenes to the NCBI 'nr' (non-redundant), SwissProt, KEGG, and clusters of orthologous groups (COG) databases, where 52,531 (68.6%) unigenes were functionally annotated. According to the annotation, 46,171 (60.8%) unigenes belong to 338 KEGG pathways. We identified a series of unigenes that are related to the synthesis and regulation of abscisic acid (ABA), the activity of protective enzymes, vitamin B6 metabolism, the metabolism of osmolytes, and pathways related to the biosynthesis of secondary metabolites. After exposed to drought for 12 hours, the number of differentially-expressed genes (DEGs) between treated plants and control plants increased in the G4 cultivar, while there was no significant increase in the drought-tolerant C3 cultivar. DEGs associated with drought stress responsive pathways were identified by KEGG pathway enrichment analysis. Moreover, we found 789 DEGs related to transcription factors. Finally, according to the results of qRT-PCR, the expression levels of the 20 unigenes tested were consistent with the results of next-generation sequencing. CONCLUSIONS In the present study, we identified a large set of cDNA unigenes from C. oleifera annotated using public databases. Further studies of DEGs involved in metabolic pathways related to drought stress and transcription will facilitate the discovery of novel genes involved in resistance to drought stress in this commercially important plant.
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Affiliation(s)
- Bin Dong
- South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Agriculture Industry Business Polytechnic, Guangzhou, Guangdong, China
| | - Bin Wu
- DRIGEN Company Limited, Shenzhen, Guangdong, China
| | - Wenhong Hong
- South China Agricultural University, Guangzhou, Guangdong, China
| | - Xiuping Li
- South China Agricultural University, Guangzhou, Guangdong, China
- Guangdong Agriculture Industry Business Polytechnic, Guangzhou, Guangdong, China
| | - Zhuo Li
- The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Li Xue
- South China Agricultural University, Guangzhou, Guangdong, China
- * E-mail: (YH); (LX)
| | - Yongfang Huang
- South China Agricultural University, Guangzhou, Guangdong, China
- * E-mail: (YH); (LX)
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Selim S, Sanssené J, Rossard S, Courtois J. Systemic Induction of the Defensin and Phytoalexin Pisatin Pathways in Pea (Pisum sativum) against Aphanomyces euteiches by Acetylated and Nonacetylated Oligogalacturonides. Molecules 2017; 22:E1017. [PMID: 28629201 PMCID: PMC6152630 DOI: 10.3390/molecules22061017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 06/16/2017] [Accepted: 06/17/2017] [Indexed: 01/15/2023] Open
Abstract
Oligogalacturonides (OGs) are known for their powerful ability to stimulate the plant immune system but little is known about their mode of action in pea (Pisum sativum). In the present study, we investigated the elicitor activity of two fractions of OGs, with polymerization degrees (DPs) of 2-25, in pea against Aphanomyces euteiches. One fraction was nonacetylated (OGs - Ac) whereas the second one was 30% acetylated (OGs + Ac). OGs were applied by injecting the upper two rachises of the plants at three- and/or four-weeks-old. Five-week-old roots were inoculated with 10⁵ zoospores of A. euteiches. The root infection level was determined at 7, 10 and 14 days after inoculation using the quantitative real-time polymerase chain reaction (qPCR). Results showed significant root infection reductions namely 58, 45 and 48% in the plants treated with 80 µg OGs + Ac and 59, 56 and 65% with 200 µg of OGs - Ac. Gene expression results showed the upregulation of genes involved in the antifungal defensins, lignans and the phytoalexin pisatin pathways and a priming effect in the basal defense, SA and ROS gene markers as a response to OGs. The reduction of the efficient dose in OGs + Ac is suggesting that acetylation is necessary for some specific responses. Our work provides the first evidence for the potential of OGs in the defense induction in pea against Aphanomyces root rot.
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Affiliation(s)
- Sameh Selim
- HydrISE, UniLaSalle, Beauvais, SFR Condorcet 3417, 19 Rue Pierre Waguet, BP 30313, F-60026 Beauvais CEDEX, France.
| | - Jean Sanssené
- Current address: JS Consulting, 17c Avenue Jean Jaurès, 31290 Villefranche de Lauragais, France.
| | - Stéphanie Rossard
- Current address: University of Technology of Compiègne (UTC), Centre Pierre Guillaumat, Rue du Docteur Schweitzer, F-60203 Compiègne CEDEX, France.
| | - Josiane Courtois
- Laboratoire des Polysaccharides Microbiens et Végétaux, Université de Picardie Jules Verne, Avenue des Facultés, Le Bailly, F-80025 Amiens CEDEX, France.
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