title: 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. ΔMorfx1 displayed increased sensitivity to UV light, four DNA-damaging agents and three cell wall-perturbing compounds. However, ΔMorfx1 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 ΔMorfx1, and ΔMorfx1 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 ΔMorfx1, and deletion of MoCDA2 and MoCDA1, similar to ΔMorfx1, 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.
authors.affiliation: State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Sun
authors.affiliation: State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.|State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Cao
authors.affiliation: State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Yongkai
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Pengyun
authors.initials: P
authors.lastname: Huang
authors.affiliation: Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang Province, 310021, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Dong
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Rice Biology, Biotechnology Institute, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Fucheng
authors.initials: F
authors.lastname: Lin
authors.affiliation: State Key Laboratory for Rice Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang Province, 310058, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lu
mesh_terms: D002455:Cell Division; D002467:Cell Nucleus / Q000378:metabolism; D002473:Cell Wall / Q000378:metabolism; D002686:Chitin / Q000378:metabolism; D004249:DNA Damage; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D020082:Magnaporthe / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity*; D009154:Mutation / Q000235:genetics; D025282:Mycelium / Q000235:genetics / Q000378:metabolism; D012275:Oryza / Q000382:microbiology*; D010641:Phenotype; D010935:Plant Diseases / Q000382:microbiology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013172:Spores, Fungal / Q000254:growth & development
chemical_list: D005656:Fungal Proteins; D012333:RNA, Messenger; D002686:Chitin
keywords: Magnaporthe oryzae; cell division; conidiation; pathogenicity; regulatory factor X; rice blast; transcription factor