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Hiroyuki Kanzaki - One of the best experts on this subject based on the ideXlab platform.
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a chloroplast localized protein lesion and lamina bending affects defence and growth responses in rice
New Phytologist, 2016Co-Authors: Muluneh Tamiru, Hiroyuki Kanzaki, Hiromasa Saitoh, Hiroki Takagi, Takao Yokota, Haruko Okamoto, Hideyuki Takahashi, Koki Fujisaki, Kaori Oikawa, Aiko UemuraAbstract:Summary Understanding how plants allocate their resources to growth or defence is of long-term importance to the development of new and improved varieties of different crops. Using molecular genetics, plant physiology, hormone analysis and Next-Generation Sequencing (NGS)-based transcript profiling, we have isolated and characterized the rice (Oryza sativa) LESION AND LAMINA BENDING (LLB) gene that encodes a chloroplast-targeted putative leucine carboxyl methyltransferase. Loss of LLB function results in reduced growth and yield, hypersensitive response (HR)-like lesions, accumulation of the antimicrobial compounds momilactones and phytocassanes, and constitutive expression of pathogenesis-related genes. Consistent with these defence-associated responses, llb shows enhanced resistance to rice blast (Magnaporthe Oryzae) and bacterial blight (Xanthomonas Oryzae pv. Oryzae). The lesion and resistance phenotypes are likely to be caused by the over-accumulation of jasmonates (JAs) in the llb mutant including the JA precursor 12-oxo-phytodienoic acid. Additionally, llb shows an increased lamina inclination and enhanced early seedling growth due to elevated brassinosteroid (BR) synthesis and/or signalling. These findings show that LLB functions in the chloroplast to either directly or indirectly repress both JA- and BR-mediated responses, revealing a possible mechanism for controlling how plants allocate resources for defence and growth.
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the rice resistance protein pair rga4 rga5 recognizes the magnaporthe Oryzae effectors avr pia and avr1 co39 by direct binding
The Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki KanzakiAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer–fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
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The rice resistance protein pair RGA4/RGA5 recognizes the Magnaporthe Oryzae effectors AVR-Pia and AVR1-CO39 by direct binding
Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki Kanzaki, Yudai OkuyamaAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer-fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
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association genetics reveals three novel avirulence genes from the rice blast fungal pathogen magnaporthe Oryzae
The Plant Cell, 2009Co-Authors: Kentaro Yoshida, Hiroyuki Kanzaki, Hiromasa Saitoh, Izumi Chuma, Yukio Tosa, Shizuko Fujisawa, Hideo Matsumura, Kakoto Yoshida, Yoshitaka Takano, Sophien KamounAbstract:To subvert rice (Oryza sativa) host defenses, the devastating ascomycete fungus pathogen Magnaporthe Oryzae produces a battery of effector molecules, including some with avirulence (AVR) activity, which are recognized by host resistance (R) proteins resulting in rapid and effective activation of innate immunity. To isolate novel avirulence genes from M. Oryzae ,w e examined DNA polymorphisms of secreted protein genes predicted from the genome sequence of isolate 70-15 and looked for an association with AVR activity. This large-scale study found significantly more presence/absence polymorphisms than nucleotide polymorphisms among 1032 putative secreted protein genes. Nucleotide diversity of M. Oryzae among 46 isolates of a worldwide collection was extremely low (u = 8.2 3 10 25 ), suggestive of recent pathogen dispersal. However, no association between DNA polymorphism and AVR was identified. Therefore, we used genome resequencing of Ina168, an M. Oryzae isolate that contains nine AVR genes. Remarkably, a total of 1.68 Mb regions, comprising 316 candidate effector genes, were present in Ina168 but absent in the assembled sequence of isolate 70-15. Association analyses of these 316 genes revealed three novel AVR genes, AVR-Pia, AVR-Pii, and AVR-Pik/km/kp, corresponding to five previously known AVR genes, whose products are recognized inside rice cells possessing the cognate R genes. AVR-Pia and AVR-Pii have evolved by gene gain/loss processes, whereas AVR-Pik/km/kp has evolved by nucleotide substitutions and gene gain/loss.
Susana Rivas - One of the best experts on this subject based on the ideXlab platform.
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the rice resistance protein pair rga4 rga5 recognizes the magnaporthe Oryzae effectors avr pia and avr1 co39 by direct binding
The Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki KanzakiAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer–fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
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The rice resistance protein pair RGA4/RGA5 recognizes the Magnaporthe Oryzae effectors AVR-Pia and AVR1-CO39 by direct binding
Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki Kanzaki, Yudai OkuyamaAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer-fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
Stella Cesari - One of the best experts on this subject based on the ideXlab platform.
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the rice resistance protein pair rga4 rga5 recognizes the magnaporthe Oryzae effectors avr pia and avr1 co39 by direct binding
The Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki KanzakiAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer–fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
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The rice resistance protein pair RGA4/RGA5 recognizes the Magnaporthe Oryzae effectors AVR-Pia and AVR1-CO39 by direct binding
Plant Cell, 2013Co-Authors: Stella Cesari, Cécile Ribot, Corinne Michel, Gaëtan Thilliez, Ludovic Alaux, Veronique Chalvon, Susana Rivas, Alain Jauneau, Hiroyuki Kanzaki, Yudai OkuyamaAbstract:Resistance (R) proteins recognize pathogen avirulence (Avr) proteins by direct or indirect binding and are multidomain proteins generally carrying a nucleotide binding (NB) and a leucine-rich repeat (LRR) domain. Two NB-LRR protein-coding genes from rice (Oryza sativa), RGA4 and RGA5, were found to be required for the recognition of the Magnaporthe Oryzae effector AVR1-CO39. RGA4 and RGA5 also mediate recognition of the unrelated M. Oryzae effector AVR-Pia, indicating that the corresponding R proteins possess dual recognition specificity. For RGA5, two alternative transcripts, RGA5-A and RGA5-B, were identified. Genetic analysis showed that only RGA5-A confers resistance, while RGA5-B is inactive. Yeast two-hybrid, coimmunoprecipitation, and fluorescence resonance energy transfer-fluorescence lifetime imaging experiments revealed direct binding of AVR-Pia and AVR1-CO39 to RGA5-A, providing evidence for the recognition of multiple Avr proteins by direct binding to a single R protein. Direct binding seems to be required for resistance as an inactive AVR-Pia allele did not bind RGA5-A. A small Avr interaction domain with homology to the Avr recognition domain in the rice R protein Pik-1 was identified in the C terminus of RGA5-A. This reveals a mode of Avr protein recognition through direct binding to a novel, non-LRR interaction domain.
Hiromasa Saitoh - One of the best experts on this subject based on the ideXlab platform.
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a chloroplast localized protein lesion and lamina bending affects defence and growth responses in rice
New Phytologist, 2016Co-Authors: Muluneh Tamiru, Hiroyuki Kanzaki, Hiromasa Saitoh, Hiroki Takagi, Takao Yokota, Haruko Okamoto, Hideyuki Takahashi, Koki Fujisaki, Kaori Oikawa, Aiko UemuraAbstract:Summary Understanding how plants allocate their resources to growth or defence is of long-term importance to the development of new and improved varieties of different crops. Using molecular genetics, plant physiology, hormone analysis and Next-Generation Sequencing (NGS)-based transcript profiling, we have isolated and characterized the rice (Oryza sativa) LESION AND LAMINA BENDING (LLB) gene that encodes a chloroplast-targeted putative leucine carboxyl methyltransferase. Loss of LLB function results in reduced growth and yield, hypersensitive response (HR)-like lesions, accumulation of the antimicrobial compounds momilactones and phytocassanes, and constitutive expression of pathogenesis-related genes. Consistent with these defence-associated responses, llb shows enhanced resistance to rice blast (Magnaporthe Oryzae) and bacterial blight (Xanthomonas Oryzae pv. Oryzae). The lesion and resistance phenotypes are likely to be caused by the over-accumulation of jasmonates (JAs) in the llb mutant including the JA precursor 12-oxo-phytodienoic acid. Additionally, llb shows an increased lamina inclination and enhanced early seedling growth due to elevated brassinosteroid (BR) synthesis and/or signalling. These findings show that LLB functions in the chloroplast to either directly or indirectly repress both JA- and BR-mediated responses, revealing a possible mechanism for controlling how plants allocate resources for defence and growth.
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host specialization of the blast fungus magnaporthe Oryzae is associated with dynamic gain and loss of genes linked to transposable elements
BMC Genomics, 2016Co-Authors: Kentaro Yoshida, Diane G O Saunders, Chikako Mitsuoka, Satoshi Natsume, Shunichi Kosugi, Hiromasa Saitoh, Yoshihiro Inoue, Izumi Chuma, Yukio TosaAbstract:Magnaporthe Oryzae (anamorph Pyricularia Oryzae) is the causal agent of blast disease of Poaceae crops and their wild relatives. To understand the genetic mechanisms that drive host specialization of M. Oryzae, we carried out whole genome resequencing of four M. Oryzae isolates from rice (Oryza sativa), one from foxtail millet (Setaria italica), three from wild foxtail millet S. viridis, and one isolate each from finger millet (Eleusine coracana), wheat (Triticum aestivum) and oat (Avena sativa), in addition to an isolate of a sister species M. grisea, that infects the wild grass Digitaria sanguinalis. Whole genome sequence comparison confirmed that M. Oryzae Oryza and Setaria isolates form a monophyletic and close to another monophyletic group consisting of isolates from Triticum and Avena. This supports previous phylogenetic analysis based on a small number of genes and molecular markers. When comparing the host specific subgroups, 1.2–3.5 % of genes showed presence/absence polymorphisms and 0–6.5 % showed an excess of non-synonymous substitutions. Most of these genes encoded proteins whose functional domains are present in multiple copies in each genome. Therefore, the deleterious effects of these mutations could potentially be compensated by functional redundancy. Unlike the accumulation of nonsynonymous nucleotide substitutions, gene loss appeared to be independent of divergence time. Interestingly, the loss and gain of genes in pathogens from the Oryza and Setaria infecting lineages occurred more frequently when compared to those infecting Triticum and Avena even though the genetic distance between Oryza and Setaria lineages was smaller than that between Triticum and Avena lineages. In addition, genes showing gain/loss and nucleotide polymorphisms are linked to transposable elements highlighting the relationship between genome position and gene evolution in this pathogen species. Our comparative genomics analyses of host-specific M. Oryzae isolates revealed gain and loss of genes as a major evolutionary mechanism driving specialization to Oryza and Setaria. Transposable elements appear to facilitate gene evolution possibly by enhancing chromosomal rearrangements and other forms of genetic variation.
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effector mediated suppression of chitin triggered immunity by magnaporthe Oryzae is necessary for rice blast disease
The Plant Cell, 2012Co-Authors: Thomas A Mentlak, Hiromasa Saitoh, Anja Kombrink, Tomonori Shinya, Lauren S Ryder, Ippei Otomo, Ryohei Terauchi, Yoko Nishizawa, Naoto Shibuya, Bart P H J ThommaAbstract:Plants use pattern recognition receptors to defend themselves from microbial pathogens. These receptors recognize pathogen-associated molecular patterns (PAMPs) and activate signaling pathways that lead to immunity. In rice (Oryza sativa), the chitin elicitor binding protein (CEBiP) recognizes chitin oligosaccharides released from the cell walls of fungal pathogens. Here, we show that the rice blast fungus Magnaporthe Oryzae overcomes this first line of plant defense by secreting an effector protein, Secreted LysM Protein1 (Slp1), during invasion of new rice cells. We demonstrate that Slp1 accumulates at the interface between the fungal cell wall and the rice plasma membrane, can bind to chitin, and is able to suppress chitin-induced plant immune responses, including generation of reactive oxygen species and plant defense gene expression. Furthermore, we show that Slp1 competes with CEBiP for binding of chitin oligosaccharides. Slp1 is required by M. Oryzae for full virulence and exerts a significant effect on tissue invasion and disease lesion expansion. By contrast, gene silencing of CEBiP in rice allows M. Oryzae to cause rice blast disease in the absence of Slp1. We propose that Slp1 sequesters chitin oligosaccharides to prevent PAMP-triggered immunity in rice, thereby facilitating rapid spread of the fungus within host tissue.
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association genetics reveals three novel avirulence genes from the rice blast fungal pathogen magnaporthe Oryzae
The Plant Cell, 2009Co-Authors: Kentaro Yoshida, Hiroyuki Kanzaki, Hiromasa Saitoh, Izumi Chuma, Yukio Tosa, Shizuko Fujisawa, Hideo Matsumura, Kakoto Yoshida, Yoshitaka Takano, Sophien KamounAbstract:To subvert rice (Oryza sativa) host defenses, the devastating ascomycete fungus pathogen Magnaporthe Oryzae produces a battery of effector molecules, including some with avirulence (AVR) activity, which are recognized by host resistance (R) proteins resulting in rapid and effective activation of innate immunity. To isolate novel avirulence genes from M. Oryzae ,w e examined DNA polymorphisms of secreted protein genes predicted from the genome sequence of isolate 70-15 and looked for an association with AVR activity. This large-scale study found significantly more presence/absence polymorphisms than nucleotide polymorphisms among 1032 putative secreted protein genes. Nucleotide diversity of M. Oryzae among 46 isolates of a worldwide collection was extremely low (u = 8.2 3 10 25 ), suggestive of recent pathogen dispersal. However, no association between DNA polymorphism and AVR was identified. Therefore, we used genome resequencing of Ina168, an M. Oryzae isolate that contains nine AVR genes. Remarkably, a total of 1.68 Mb regions, comprising 316 candidate effector genes, were present in Ina168 but absent in the assembled sequence of isolate 70-15. Association analyses of these 316 genes revealed three novel AVR genes, AVR-Pia, AVR-Pii, and AVR-Pik/km/kp, corresponding to five previously known AVR genes, whose products are recognized inside rice cells possessing the cognate R genes. AVR-Pia and AVR-Pii have evolved by gene gain/loss processes, whereas AVR-Pik/km/kp has evolved by nucleotide substitutions and gene gain/loss.
Bharat B. Chattoo - One of the best experts on this subject based on the ideXlab platform.
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Expression of a plant defensin in rice confers resistance to fungal phytopathogens
Transgenic Research, 2010Co-Authors: Bharat B. ChattooAbstract:Transgenic rice ( Oryza sativa L. cv. Pusa basmati 1), overexpressing the Rs-AFP2 defensin gene from the Raphanus sativus was generated by Agrobacterium tumefaciens -mediated transformation. Expression levels of Rs-AFP2 ranged from 0.45 to 0.53% of total soluble protein in transgenic plants. It was observed that constitutive expression of Rs-AFP2 suppresses the growth of Magnaporthe Oryzae and Rhizoctonia solani by 77 and 45%, respectively. No effect on plant morphology was observed in the Rs-AFP2 expressing rice lines. The inhibitory activity of protein extracts prepared from leaves of Rs-AFP2 plants on the in vitro growth of M. Oryzae indicated that the Rs-AFP2 protein produced by transgenic rice plants was biologically active. Transgene expression of Rs-AFP2 was not accompanied by an induction of pathogenesis-related (PR) gene expression, suggesting that the expression of Rs-AFP2 directly inhibits the pathogens. Here, we demonstrate that transgenic rice plants expressing the Rs-AFP2 gene show enhanced resistance to M. Oryzae and R. solani , two of the most important pathogens of rice.
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expression of dm amp1 in rice confers resistance to magnaporthe Oryzae and rhizoctonia solani
Transgenic Research, 2009Co-Authors: Harsukh G Tank, Bishun Deo Prasad, Bharat B. ChattooAbstract:Magnaporthe Oryzae and Rhizoctonia solani, are among the most important pathogens of rice, severely limiting its productivity. Dm-AMP1, an antifungal plant defensin from Dahlia merckii, was expressed in rice (Oryza sativa L. sp. indica cv. Pusa basmati 1) using Agrobacterium tumefaciens-mediated transformation. Expression levels of Dm-AMP1 ranged from 0.43% to 0.57% of total soluble protein in transgenic plants. It was observed that constitutive expression of Dm-AMP1 suppresses the growth of M. Oryzae and R. solani by 84% and 72%, respectively. Transgenic expression of Dm-AMP1 was not accompanied by an induction of pathogenesis-related (PR) gene expression, indicating that the expression of DmAMP1 directly inhibits the pathogen. The results of in vitro, in planta and microscopic analyses suggest that Dm-AMP1 expression has the potential to provide broad-spectrum disease resistance in rice.
