Dataset Information

The regulatory factor X protein MoRfx1 is required for development and pathogenicity in the rice blast fungus Magnaporthe oryzae.

ABSTRACT: Magnaporthe oryzae is a cereal pathogen causing 20%-30% rice yield losses. Regulatory factor X transcription factors are highly conserved proteins with diverse functions among organisms. Here, we show that MoRfx1 is required for cell division, development and pathogenicity in M. oryzae. Deletion of MoRFX1 resulted in reduced growth and conidiation, decreased appressorium turgor and impaired virulence. ?Morfx1 displayed increased sensitivity to UV light, four DNA-damaging agents and three cell wall-perturbing compounds. However, ?Morfx1 showed decreased sensitivity to bleomycin, a DNA/cell wall-damaging agent, and increased chitin content of the cell wall in vegetative mycelium. In addition, cell division speed was reduced in ?Morfx1, and ?Morfx1 did not produce three-celled conidia. RNA-sequencing and quantitative polymerase chain reaction analyses suggested that MoRfx1 has bipartite functions in the control of the expression of genes required for cell division and chitin metabolism, not only as a transcriptional repressor, but also as a transcriptional activator. In particular, the expression of chitin deacetylase genes MoCDA2 and MoCDA1 was greatly down-regulated in ?Morfx1, and deletion of MoCDA2 and MoCDA1, similar to ?Morfx1, increased resistance to bleomycin. Taken together, our results indicate that MoRFX1 regulates development and pathogenicity by modulating the expression of genes involved in cell division and cell wall integrity.

SUBMITTER: Sun D

PROVIDER: S-EPMC6638216 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The regulatory factor X protein MoRfx1 is required for development and pathogenicity in the rice blast fungus Magnaporthe oryzae.

Sun Dandan D Cao Huijuan H Shi Yongkai Y Huang Pengyun P Dong Bo B Liu Xiaohong X Lin Fucheng F Lu Jianping J

Molecular plant pathology 20160920 8

Magnaporthe oryzae is a cereal pathogen causing 20%-30% rice yield losses. Regulatory factor X transcription factors are highly conserved proteins with diverse functions among organisms. Here, we show that MoRfx1 is required for cell division, development and pathogenicity in M. oryzae. Deletion of MoRFX1 resulted in reduced growth and conidiation, decreased appressorium turgor and impaired virulence. ΔMorfx1 displayed increased sensitivity to UV light, four DNA-damaging agents and three cell wa ...[more]

PMID: 27434465

Similar Datasets

Project description:Rice blast disease caused by Magnaporthe oryzae is a devastating disease of cultivated rice worldwide. Infections by this fungus lead to a significant reduction in rice yields and threats to food security. To gain better insight into growth and cell death in M. oryzae during infection, we characterized two predicted M. oryzae metacaspase proteins, MoMca1 and MoMca2. These proteins appear to be functionally redundant and can complement the yeast Yca1 homologue. Biochemical analysis revealed that M. oryzae metacaspases exhibited Ca2+-dependent caspase activity in vitro Deletion of both MoMca1 and MoMca2 in M. oryzae resulted in reduced sporulation, delay in conidial germination, and attenuation of disease severity. In addition, the double ?Momca1mca2 mutant strain showed increased radial growth in the presence of oxidative stress. Interestingly, the ?Momca1mca2 strain showed an increased accumulation of insoluble aggregates compared to the wild-type strain during vegetative growth. Our findings suggest that MoMca1 and MoMca2 promote the clearance of insoluble aggregates in M. oryzae, demonstrating the important role these metacaspases have in fungal protein homeostasis. Furthermore, these metacaspase proteins may play additional roles, like in regulating stress responses, that would help maintain the fitness of fungal cells required for host infection.IMPORTANCE Magnaporthe oryzae causes rice blast disease that threatens global food security by resulting in the severe loss of rice production every year. A tightly regulated life cycle allows M. oryzae to disarm the host plant immune system during its biotrophic stage before triggering plant cell death in its necrotrophic stage. The ways M. oryzae navigates its complex life cycle remain unclear. This work characterizes two metacaspase proteins with peptidase activity in M. oryzae that are shown to be involved in the regulation of fungal growth and development prior to infection by potentially helping maintain fungal fitness. This study provides new insights into the role of metacaspase proteins in filamentous fungi by illustrating the delays in M. oryzae morphogenesis in the absence of these proteins. Understanding the mechanisms by which M. oryzae morphology and development promote its devastating pathogenicity may lead to the emergence of proper methods for disease control.

Project description:BACKGROUND: Magnaporthe oryzae, the causal agent of blast disease of rice, is the most destructive disease of rice worldwide. The genome of this fungal pathogen has been sequenced and an automated annotation has recently been updated to Version 6 http://www.broad.mit.edu/annotation/genome/magnaporthe_grisea/MultiDownloads.html. However, a comprehensive manual curation remains to be performed. Gene Ontology (GO) annotation is a valuable means of assigning functional information using standardized vocabulary. We report an overview of the GO annotation for Version 5 of M. oryzae genome assembly. METHODS: A similarity-based (i.e., computational) GO annotation with manual review was conducted, which was then integrated with a literature-based GO annotation with computational assistance. For similarity-based GO annotation a stringent reciprocal best hits method was used to identify similarity between predicted proteins of M. oryzae and GO proteins from multiple organisms with published associations to GO terms. Significant alignment pairs were manually reviewed. Functional assignments were further cross-validated with manually reviewed data, conserved domains, or data determined by wet lab experiments. Additionally, biological appropriateness of the functional assignments was manually checked. RESULTS: In total, 6,286 proteins received GO term assignment via the homology-based annotation, including 2,870 hypothetical proteins. Literature-based experimental evidence, such as microarray, MPSS, T-DNA insertion mutation, or gene knockout mutation, resulted in 2,810 proteins being annotated with GO terms. Of these, 1,673 proteins were annotated with new terms developed for Plant-Associated Microbe Gene Ontology (PAMGO). In addition, 67 experiment-determined secreted proteins were annotated with PAMGO terms. Integration of the two data sets resulted in 7,412 proteins (57%) being annotated with 1,957 distinct and specific GO terms. Unannotated proteins were assigned to the 3 root terms. The Version 5 GO annotation is publically queryable via the GO site http://amigo.geneontology.org/cgi-bin/amigo/go.cgi. Additionally, the genome of M. oryzae is constantly being refined and updated as new information is incorporated. For the latest GO annotation of Version 6 genome, please visit our website http://scotland.fgl.ncsu.edu/smeng/GoAnnotationMagnaporthegrisea.html. The preliminary GO annotation of Version 6 genome is placed at a local MySql database that is publically queryable via a user-friendly interface Adhoc Query System. CONCLUSION: Our analysis provides comprehensive and robust GO annotations of the M. oryzae genome assemblies that will be solid foundations for further functional interrogation of M. oryzae.

Dataset Information

The regulatory factor X protein MoRfx1 is required for development and pathogenicity in the rice blast fungus Magnaporthe oryzae.

Publications

The regulatory factor X protein MoRfx1 is required for development and pathogenicity in the rice blast fungus Magnaporthe oryzae.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure