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Hu J, Chang R, Yuan Y, Li Z, Wang Y. Identification of Key Residues Essential for the Activation of Plant Immunity by Subtilisin From Bacillus velezensis LJ02. Front Microbiol 2022; 13:869596. [PMID: 36046019 PMCID: PMC9421249 DOI: 10.3389/fmicb.2022.869596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 06/17/2022] [Indexed: 11/13/2022] Open
Abstract
Subtilisin, a serine protease, can trigger defense responses in a wide variety of plants, both locally and systemically, to protect against pathogens. However, key residues of subtilisin to improve resistance to plant diseases remain unknown. In this study, Nicotiana benthamiana (N. benthamiana) leaves expressing subtilisin from Bacillus velezensis LJ02 were shown to improve protection against Botrytis cinerea (B. cinerea). Furthermore, the underlying mechanism that LJ02 subtilisin improved the protective effect was explored, and the direct inhibitory effect of subtilisin on B. cinerea was excluded in vitro. Subsequently, reactive oxygen species (ROS) burst and upregulation of resistance-related genes in systemic leaves of N. benthamiana further verified that subtilisin could induce systemic protection against B. cinerea. G307A/T308A and S213A/L214A/G215A subtilisin significantly reduced the ability to resist B. cinerea infection in N. benthamiana. Furthermore, the ROS content and expression levels of resistance-related genes of both mutants were significantly decreased compared with that of wild-type subtilisin. This work identified key residues essential for the activation function of subtilisin plant immunity and was crucial in inducing plant defense responses against B. cinerea.
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Affiliation(s)
- Jianan Hu
- College of Horticulture and Landscape Architecture, Tianjin Agricultural University, Tianjin, China
| | - Ruokui Chang
- College of Engineering and Technology, Tianjin Agricultural University, Tianjin, China
| | - Yujin Yuan
- College of Horticulture and Landscape Architecture, Tianjin Agricultural University, Tianjin, China
| | - Zhuoran Li
- College of Horticulture and Landscape Architecture, Tianjin Agricultural University, Tianjin, China
- Zhuoran Li,
| | - Yuanhong Wang
- College of Horticulture and Landscape Architecture, Tianjin Agricultural University, Tianjin, China
- *Correspondence: Yuanhong Wang,
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Li Y, Jiao Y, Shi J, Xie J, Yin J, Zhao X, Chen H. BLB8, an antiviral protein from Brevibacillus laterosporus strain B8, inhibits Tobacco mosaic virus infection by triggering immune response in tobacco. PEST MANAGEMENT SCIENCE 2021; 77:4383-4392. [PMID: 33969944 DOI: 10.1002/ps.6472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 05/05/2021] [Accepted: 05/10/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Tobacco mosaic virus (TMV) is one of destructive plant viruses, causing serious economic losses in the world. Using antiviral proteins or elicitors to inhibit viral infection or promote plant immunity is one of the efficient strategies against TMV. Our previous study identified that the fermentation broth of Brevibacillus laterosporus strain B8 showed strong antiviral activity against TMV. However, the active antiviral ingredient is still unclear. RESULTS Here, BLB8 (B. laterosporus strain B8 protein, BLB8), an antiviral protein from B. laterosporus strain B8 was isolated and characterized. BLB8 showed protective, inactive and curative effects against TMV, and the inhibition rate reached up to 63%, 83% and 55%, respectively. BLB8 infiltrated around the infection site of the recombinant virus TMV-GFP inhibited the systemic extend and movement of TMV. Pretreatment of the bottom leaves with BLB8 inhibited the spread and accumulation of TMV in upper systemic leaves. Furthermore, BLB8 caused hypersensitive response (HR) in a dose-dependent way, promoted H2 O2 accumulation, and induced the expression of defense-relative genes in Nicotiana benthamiana. CONCLUSION The antiviral protein BLB8 from B. laterosporus strain B8 effectively inhibits TMV infection in inactivation, protective and curative effects through triggering plant immunity in tobacco. Therefore, the present study provides a new antiviral agent for prevention and control of viral disease. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Yanfang Li
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Yubing Jiao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Jia Shi
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jingjing Xie
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Jing Yin
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Xiuxiang Zhao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, China
| | - Huamin Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Jatoi GH, Lihua G, Xiufen Y, Gadhi MA, Keerio AU, Abdulle YA, Qiu D. A Novel Protein Elicitor PeBL2, from Brevibacillus laterosporus A60, Induces Systemic Resistance against Botrytis cinerea in Tobacco Plant. THE PLANT PATHOLOGY JOURNAL 2019; 35:208-218. [PMID: 31244567 PMCID: PMC6586191 DOI: 10.5423/ppj.oa.11.2018.0276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 02/26/2019] [Accepted: 03/28/2019] [Indexed: 06/09/2023]
Abstract
Here, we reported a novel secreted protein elicitor PeBL2 from Brevibacillus laterosporus A60, which can induce hypersensitive response in tobacco (Nicotiana benthamiana). The ion-exchange chromatography, high-performance liquid chromatography (HPLC) and mass spectrometry were performed for identification of protein elicitor. The 471 bp PeBL2 gene produces a 17.22 kDa protein with 156 amino acids containing an 84-residue signal peptide. Consistent with endogenous protein, the recombinant protein expressed in Escherichia coli induced the typical hypersensitive response (HR) and necrosis in tobacco leaves. Additionally, PeBL2 also triggered early defensive response of generation of reactive oxygen species (H2O2 and O2 -) and systemic resistance against of B. cinerea. Our findings shed new light on a novel strategy for biocontrol using B. laterosporus A60.
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Affiliation(s)
- Ghulam Hussain Jatoi
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
- Department of Plant Pathology Sindh Agriculture University Tandojam, Sindh,
Pakistan
| | - Guo Lihua
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
| | - Yang Xiufen
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
| | - Muswar Ali Gadhi
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
| | - Azhar Uddin Keerio
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
| | - Yusuf Ali Abdulle
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
| | - Dewen Qiu
- State Key Laboratory of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081,
China
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Cheng XX, Zhao LH, Klosterman SJ, Feng HJ, Feng ZL, Wei F, Shi YQ, Li ZF, Zhu HQ. The endochitinase VDECH from Verticillium dahliae inhibits spore germination and activates plant defense responses. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2017; 259:12-23. [PMID: 28483050 DOI: 10.1016/j.plantsci.2017.03.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 03/01/2017] [Accepted: 03/06/2017] [Indexed: 05/06/2023]
Abstract
Chitinases function in the digestion of chitin molecules, which are present principally in insects and fungi. In plants, chitinase genes play important roles in defense, and their expression can be triggered in response to both biotic and abiotic stresses. In this study, we cloned and characterized an endochitinase (VDECH) from Verticillium dahliae, strain Vd080. The VDECH coding region consists of 1845bp with two exons and one 54bp intron, encoding a 615 amino acid protein with the predicted molecular weight (MW) of 63.9kDa. The VDECH cDNA without signal peptide-encoding region was introduced into pCold-TF vector and the recombinant protein HIS-VDECH with a predicted MW of ∼114kDa was expressed. HIS-VDECH showed high tolerance to extreme temperature, exhibiting efficient chitinolytic activity at 50°C. In addition, VDECH triggered typical plant defense responses, including a hypersensitive response, oxidative burst, and elicited increased expression of defense-related genes in both Arabidopsis and cotton. VDECH-treatment of the conidial spores of V. dahliae and Fusarium oxysporum resulted in marked reductions in the germination of these spores in both fungi. After 36h of incubation with VDECH, the inhibition rate of germination was recorded at 99.57% for V. dahliae, and 96.89% for F. oxysporum. These results provide evidence that VDECH is recognized by the plant to elicit defense responses, and also that VDECH is an effective inhibitor of conidia germination, both of which may be exploited for disease control.
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Affiliation(s)
- Xiao-Xiao Cheng
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | - Li-Hong Zhao
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | | | - Hong-Jie Feng
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | - Zi-Li Feng
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | - Feng Wei
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | - Yong-Qiang Shi
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China
| | - Zhi-Fang Li
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China.
| | - He-Qin Zhu
- State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan, 455000, China.
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Wang N, Liu M, Guo L, Yang X, Qiu D. A Novel Protein Elicitor (PeBA1) from Bacillus amyloliquefaciens NC6 Induces Systemic Resistance in Tobacco. Int J Biol Sci 2016; 12:757-67. [PMID: 27194952 PMCID: PMC4870718 DOI: 10.7150/ijbs.14333] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/02/2016] [Indexed: 01/09/2023] Open
Abstract
Here we reported a novel protein elicitor from Bacillus amyloliquefaciens NC6 induced systemic resistance (ISR) in tobacco. The purification was executed by ion-exchange chromatography, native-page extraction and HPLC, and the amino acid sequence was identified by mass spectrometry. This recombinant elicitor protein, expressed in Escherichia coli by an E1 expression vector, had good thermal stability, and the elicitor caused a clearly defined hypersensitive response (HR) necrosis in tobacco leaves. It could also trigger early defence events, including generation of reactive oxygen species (H2O2 and O2 (-)) and phenolic-compound accumulation. Quantitative real-time PCR (Q-RT-PCR) results indicated that several plant defence genes, including the salicylic acid (SA)-responsive PR1a, PR1b, PR5, and phenylalanine ammonia lyase (PAL), as well as the jasmonic acid (JA)-responsive PDF1.2 and CORONATINE INSENSITIVE 1 (COI1), were all up-regulated. Moreover, infiltration conferred systemic resistance against a broad spectrum of pathogens, including Tobacco mosaic virus (TMV) and the fungal pathogen Botrytis cinerea.
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Affiliation(s)
| | | | | | | | - Dewen Qiu
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant protection, Chinese Academy of Agricultural sciences, No. 12 Zhongguancun South Street, Beijing 100081, China
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Wang H, Yang X, Guo L, Zeng H, Qiu D. PeBL1, a novel protein elicitor from Brevibacillus laterosporus strain A60, activates defense responses and systemic resistance in Nicotiana benthamiana. Appl Environ Microbiol 2015; 81:2706-16. [PMID: 25662975 PMCID: PMC4375336 DOI: 10.1128/aem.03586-14] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 01/30/2015] [Indexed: 11/20/2022] Open
Abstract
We report the identification, characterization, and gene cloning of a novel protein elicitor (PeBL1) secreted from Brevibacillus laterosporus strain A60. Through a purification process consisting of ion-exchange chromatography and high-performance liquid chromatography (HPLC), we isolated a protein that was identified by electrospray ionization quadrupole time of flight tandem mass spectrometry (ESI-Q-TOF-MS-MS). The 351-bp PeBL1 gene produces a 12,833-Da protein with 116 amino acids that contains a 30-residue signal peptide. The PeBL1 protein was expressed in Escherichia coli. The recombinant protein can induce a typical hypersensitive response (HR) and systemic resistance in Nicotiana benthamiana, like the endogenous protein. PeBL1-treated N. benthamiana exhibited strong resistance to the infection of tobacco mosaic virus-green fluorescent protein (TMV-GFP) and Pseudomonas syringae pv. tabaci compared to control N. benthamiana. In addition, PeBL1 triggered a cascade of events that resulted in defense responses in plants, including reactive oxygen species (ROS) production, extracellular-medium alkalization, phenolic-compound deposition, and expression of several defense-related genes. Real-time quantitative-PCR analysis indicated that the known defense-related genes PR-1, PR-5, PDF1.2, NPR1, and PAL were upregulated to varying degrees by PeBL1. This research not only provides insights into the mechanism by which beneficial bacteria activate plant systemic resistance, but also sheds new light on a novel strategy for biocontrol using strain A60.
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Affiliation(s)
- Haoqian Wang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Xiufen Yang
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Lihua Guo
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Hongmei Zeng
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
| | - Dewen Qiu
- State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, Beijing, China
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Zhang Y, Yang X, Zeng H, Guo L, Yuan J, Qiu D. Fungal elicitor protein PebC1 from Botrytis cinerea improves disease resistance in Arabidopsis thaliana. Biotechnol Lett 2014; 36:1069-78. [PMID: 24563295 DOI: 10.1007/s10529-014-1462-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 01/08/2014] [Indexed: 12/16/2022]
Abstract
We previously identified a novel protein elicitor, PebC1, from Botrytis cinerea and described its enhancement of plant growth, drought tolerance and disease resistance in tomato. Here, we have investigated the defense-associated molecular responses in Arabidopsis thaliana after treatment with recombinant PebC1. PebC1 was expressed in Escherichia coli. Recombinant protein treatments improved plant resistance to Botrytis infection and maintained plant defenses for more than 21 days. The purified protein at 10 μg ml(-1) activated extracellular medium alkalization (pH) and reactive oxygen species and nitric oxide generation and also induced defense gene expression. Arabidopsis mutants that are insensitive to salicylic acid had increased resistance to Botrytis infection after PebC1 treatment but PebC1 did not affect the resistance of mutants with jasmonic acid and ethylene transduction pathways. The results suggest that PebC1 can function as an activator of plant disease resistance and can promote disease resistance to Botrytis in A. thaliana through the ethylene signal transduction pathway.
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Affiliation(s)
- Yunhua Zhang
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 12 Zhongguancun South Street, Beijing, 100081, China
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Arencibia AD, Bernal A, Zayas C, Carmona E, Cordero C, González G, García R, Santana I. Hydrogen peroxide induced phenylpropanoids pathway eliciting a defensive response in plants micropropagated in Temporary Immersion Bioreactors (TIBs). PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2012; 195:71-79. [PMID: 22921000 DOI: 10.1016/j.plantsci.2012.06.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 06/21/2012] [Accepted: 06/25/2012] [Indexed: 06/01/2023]
Abstract
The relation between the oxidative burst and phenylpropanoid pathways has been studied using the sugarcane cultivar C86-56, which does not release phenolics in agar-base micropropagation systems. In stationary liquid culture, a significant production of phenolic compounds and plant survival were determined in sugarcane plants treated with 5mM H(2)O(2). The spectrophotometer determinations and the gene expression analysis corroborated that releasing of phenolics and soluble θ-quinones was induced during the first 24h of treatment. In comparison with the control treatments, sugarcane plants treated with H(2)O(2) demonstrated differences in the micropropagation-related variables when multiplied in Temporary Immersion Bioreactors (TIBs) supplemented with polyethyleneglycol (PEG 20%). Expression of selected genes related to photosynthesis, ethylene, auxins, oxidative burst, and defense pathways were confirmed during the entire PEG 20% stress in the plants coming from the 5mM H(2)O(2) treatment; whereas, much more heterogeneous expression patterns were evidenced in plants stressed with PEG but not previously treated with H(2)O(2). RT-PCR expression analysis supports the hypothesis that while H(2)O(2) induces the oxidative burst, the phenylpropanoids pathways elicit and maintain the defensive response mechanism in micropropagated sugarcane plants.
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Affiliation(s)
- Ariel D Arencibia
- National Institute for Sugarcane Research, CUJAE Road km 2½, Boyeros 19390, Havana, Cuba.
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Chen M, Zeng H, Qiu D, Guo L, Yang X, Shi H, Zhou T, Zhao J. Purification and characterization of a novel hypersensitive response-inducing elicitor from Magnaporthe oryzae that triggers defense response in rice. PLoS One 2012; 7:e37654. [PMID: 22624059 PMCID: PMC3356297 DOI: 10.1371/journal.pone.0037654] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 04/22/2012] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Magnaporthe oryzae, the rice blast fungus, might secrete certain proteins related to plant-fungal pathogen interactions. METHODOLOGY/PRINCIPAL FINDINGS In this study, we report the purification, characterization, and gene cloning of a novel hypersensitive response-inducing protein elicitor (MoHrip1) secreted by M. oryzae. The protein fraction was purified and identified by de novo sequencing, and the sequence matched the genomic sequence of a putative protein from M. oryzae strain 70-15 (GenBank accession No. XP_366602.1). The elicitor-encoding gene mohrip1 was isolated; it consisted of a 429 bp cDNA, which encodes a polypeptide of 142 amino acids with a molecular weight of 14.322 kDa and a pI of 4.53. The deduced protein, MoHrip1, was expressed in E. coli. And the expression protein collected from bacterium also forms necrotic lesions in tobacco. MoHrip1 could induce the early events of the defense response, including hydrogen peroxide production, callose deposition, and alkalization of the extracellular medium, in tobacco. Moreover, MoHrip1-treated rice seedlings possessed significantly enhanced systemic resistance to M. oryzae compared to the control seedlings. The real-time PCR results indicated that the expression of some pathogenesis-related genes and genes involved in signal transduction could also be induced by MoHrip1. CONCLUSION/SIGNIFICANCE The results demonstrate that MoHrip1 triggers defense responses in rice and could be used for controlling rice blast disease.
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Affiliation(s)
| | - Hongmei Zeng
- Key Laboratory of Integrated Pest Management in Crops, Ministry of Agriculture, Institute of Plant Protection, Chinses Academy of Agricultural Sciences, Beijing, China
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Wang B, Yang X, Zeng H, Liu H, Zhou T, Tan B, Yuan J, Guo L, Qiu D. The purification and characterization of a novel hypersensitive-like response-inducing elicitor from Verticillium dahliae that induces resistance responses in tobacco. Appl Microbiol Biotechnol 2012; 93:191-201. [PMID: 21691787 DOI: 10.1007/s00253-011-3405-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 05/18/2011] [Accepted: 05/19/2011] [Indexed: 12/25/2022]
Abstract
PevD1, a novel protein elicitor from the pathogenic cotton verticillium wilt fungus, Verticillium dahliae, induced a hypersensitive response in tobacco plants. In this paper, the elicitor was purified and analyzed using de novo sequencing. The protein-encoding pevD1 gene consists of a 468-bp open reading frame that produces a polypeptide of 155 amino acids, with a theoretical molecular weight of 16.23 kDa. The sequence of elicitor protein PevD1 was matched to the genomic sequence (GenBank accession no. ABJE 01000445.1) of a putative protein from V. dahliae strain vdls.17, but a function had not yet been reported. The pevD1 gene was expressed in Escherichia coli, and the recombinant protein was characterized for its ability to confer systemic acquired resistance to tobacco mosaic virus (TMV). Recombinant PevD1-treated plants exhibited enhanced systemic resistance compared to control, including a significant reduction in the number and size of TMV lesions on tobacco leaves. The elicitor protein-induced hydrogen peroxide production, extracellular-medium alkalization, callose deposition, phenolics metabolism, and lignin synthesis in tobacco. Our results demonstrate that elicitor-PevD1 triggers defense responses in intact tobacco plants.
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Affiliation(s)
- Bingnan Wang
- Key Laboratory for Biological Control of Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People's Republic of China
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