Limits...
Global genome and transcriptome analyses of Magnaporthe oryzae epidemic isolate 98-06 uncover novel effectors and pathogenicity-related genes, revealing gene gain and lose dynamics in genome evolution.

Dong Y, Li Y, Zhao M, Jing M, Liu X, Liu M, Guo X, Zhang X, Chen Y, Liu Y, Liu Y, Ye W, Zhang H, Wang Y, Zheng X, Wang P, Zhang Z - PLoS Pathog. (2015)

Bottom Line: A unique 1.4 Mb of genomic sequences was found in isolate 98-06 in comparison to reference strain 70-15.In addition, 134 candidate effectors with various segregation patterns were identified.Characterization of isolate-specific effector candidates Iug6 and Iug9 and PaR candidate Iug18 revealed that they have a role in fungal propagation and pathogenicity.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China.

ABSTRACT
Genome dynamics of pathogenic organisms are driven by pathogen and host co-evolution, in which pathogen genomes are shaped to overcome stresses imposed by hosts with various genetic backgrounds through generation of a variety of isolates. This same principle applies to the rice blast pathogen Magnaporthe oryzae and the rice host; however, genetic variations among different isolates of M. oryzae remain largely unknown, particularly at genome and transcriptome levels. Here, we applied genomic and transcriptomic analytical tools to investigate M. oryzae isolate 98-06 that is the most aggressive in infection of susceptible rice cultivars. A unique 1.4 Mb of genomic sequences was found in isolate 98-06 in comparison to reference strain 70-15. Genome-wide expression profiling revealed the presence of two critical expression patterns of M. oryzae based on 64 known pathogenicity-related (PaR) genes. In addition, 134 candidate effectors with various segregation patterns were identified. Five tested proteins could suppress BAX-mediated programmed cell death in Nicotiana benthamiana leaves. Characterization of isolate-specific effector candidates Iug6 and Iug9 and PaR candidate Iug18 revealed that they have a role in fungal propagation and pathogenicity. Moreover, Iug6 and Iug9 are located exclusively in the biotrophic interfacial complex (BIC) and their overexpression leads to suppression of defense-related gene expression in rice, suggesting that they might participate in biotrophy by inhibiting the SA and ET pathways within the host. Thus, our studies identify novel effector and PaR proteins involved in pathogenicity of the highly aggressive M. oryzae field isolate 98-06, and reveal molecular and genomic dynamics in the evolution of M. oryzae and rice host interactions.

No MeSH data available.


Related in: MedlinePlus

Heat map of 645 small candidate effectors of 98–06.645 candidate effectors were added to employ the hierarchical clustering, and divided into two groups (red rectangle and gray rectangle) according to the expression pattern of Avr-Pik and AvrPiz-t, providing 134 candidate effectors. The color bar represents the log2 of (RPKM +1) value, ranging from blue (0.0) to red (10.0).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4383609&req=5

ppat.1004801.g004: Heat map of 645 small candidate effectors of 98–06.645 candidate effectors were added to employ the hierarchical clustering, and divided into two groups (red rectangle and gray rectangle) according to the expression pattern of Avr-Pik and AvrPiz-t, providing 134 candidate effectors. The color bar represents the log2 of (RPKM +1) value, ranging from blue (0.0) to red (10.0).

Mentions: Since Avr-Pik and AvrPiz-t genes are highly expressed during infection, and studies of two M. oryzae isolate-specific sequences and Verticillium dahliae indicated that lineage-specific genomic regions are enriched in genes encoding new effectors [35], we explored the expression patterns of 645 small candidate effectors in 98–06 through CAST assay. 134 candidate effectors were found to be co-regulated with Avr-Pik and AvrPiz-t (Fig 4; S13 Table). Six known effectors BAS1, BAS2, BAS3, BAS4, SLP1, and PWL1 were among these candidates, providing a compelling argument for the presence of additional effectors among these candidates.


Global genome and transcriptome analyses of Magnaporthe oryzae epidemic isolate 98-06 uncover novel effectors and pathogenicity-related genes, revealing gene gain and lose dynamics in genome evolution.

Dong Y, Li Y, Zhao M, Jing M, Liu X, Liu M, Guo X, Zhang X, Chen Y, Liu Y, Liu Y, Ye W, Zhang H, Wang Y, Zheng X, Wang P, Zhang Z - PLoS Pathog. (2015)

Heat map of 645 small candidate effectors of 98–06.645 candidate effectors were added to employ the hierarchical clustering, and divided into two groups (red rectangle and gray rectangle) according to the expression pattern of Avr-Pik and AvrPiz-t, providing 134 candidate effectors. The color bar represents the log2 of (RPKM +1) value, ranging from blue (0.0) to red (10.0).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383609&req=5

ppat.1004801.g004: Heat map of 645 small candidate effectors of 98–06.645 candidate effectors were added to employ the hierarchical clustering, and divided into two groups (red rectangle and gray rectangle) according to the expression pattern of Avr-Pik and AvrPiz-t, providing 134 candidate effectors. The color bar represents the log2 of (RPKM +1) value, ranging from blue (0.0) to red (10.0).
Mentions: Since Avr-Pik and AvrPiz-t genes are highly expressed during infection, and studies of two M. oryzae isolate-specific sequences and Verticillium dahliae indicated that lineage-specific genomic regions are enriched in genes encoding new effectors [35], we explored the expression patterns of 645 small candidate effectors in 98–06 through CAST assay. 134 candidate effectors were found to be co-regulated with Avr-Pik and AvrPiz-t (Fig 4; S13 Table). Six known effectors BAS1, BAS2, BAS3, BAS4, SLP1, and PWL1 were among these candidates, providing a compelling argument for the presence of additional effectors among these candidates.

Bottom Line: A unique 1.4 Mb of genomic sequences was found in isolate 98-06 in comparison to reference strain 70-15.In addition, 134 candidate effectors with various segregation patterns were identified.Characterization of isolate-specific effector candidates Iug6 and Iug9 and PaR candidate Iug18 revealed that they have a role in fungal propagation and pathogenicity.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China; Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China.

ABSTRACT
Genome dynamics of pathogenic organisms are driven by pathogen and host co-evolution, in which pathogen genomes are shaped to overcome stresses imposed by hosts with various genetic backgrounds through generation of a variety of isolates. This same principle applies to the rice blast pathogen Magnaporthe oryzae and the rice host; however, genetic variations among different isolates of M. oryzae remain largely unknown, particularly at genome and transcriptome levels. Here, we applied genomic and transcriptomic analytical tools to investigate M. oryzae isolate 98-06 that is the most aggressive in infection of susceptible rice cultivars. A unique 1.4 Mb of genomic sequences was found in isolate 98-06 in comparison to reference strain 70-15. Genome-wide expression profiling revealed the presence of two critical expression patterns of M. oryzae based on 64 known pathogenicity-related (PaR) genes. In addition, 134 candidate effectors with various segregation patterns were identified. Five tested proteins could suppress BAX-mediated programmed cell death in Nicotiana benthamiana leaves. Characterization of isolate-specific effector candidates Iug6 and Iug9 and PaR candidate Iug18 revealed that they have a role in fungal propagation and pathogenicity. Moreover, Iug6 and Iug9 are located exclusively in the biotrophic interfacial complex (BIC) and their overexpression leads to suppression of defense-related gene expression in rice, suggesting that they might participate in biotrophy by inhibiting the SA and ET pathways within the host. Thus, our studies identify novel effector and PaR proteins involved in pathogenicity of the highly aggressive M. oryzae field isolate 98-06, and reveal molecular and genomic dynamics in the evolution of M. oryzae and rice host interactions.

No MeSH data available.


Related in: MedlinePlus