A histone deacetylase, MoHOS2 regulates asexual development and virulence in the rice blast fungus

• Published in: The journal of microbiology 2019, 57(12), , pp.1115-1125
• Main Authors: Lee, Jongjune, Lee, Jae-Joon, Jeon, Junhyun
• Format: Article
• Language: English
• Subjects: Acetylation; Amino acids; Asexual reproduction; Biomedical and Life Sciences; Cell Wall - metabolism; Clonal deletion; Conserved sequence; Deacetylation; Defects; Deletion mutant; Epigenesis, Genetic; Epigenetics; Fungal Proteins - genetics; Fungal Proteins - metabolism; Fungi; Gene Deletion; Gene expression; Gene Expression Regulation, Fungal; Genes; Histone deacetylase; Histone Deacetylases - chemistry; Histone Deacetylases - genetics; Histone Deacetylases - metabolism; Histones; Host plants; Hyphae; Inoculation; Life Sciences; Localization; Magnaporthe - enzymology; Magnaporthe - genetics; Magnaporthe - growth & development; Magnaporthe - metabolism; Microbial Pathogenesis and Host-Microbe Interaction; Microbiology; Models, Molecular; Mutagenesis, Site-Directed; Oryza - microbiology; Phenotype; Plant Diseases - microbiology; Protein Conformation; Protein Processing, Post-Translational; Reduction; Reproduction, Asexual - genetics; Reproduction, Asexual - physiology; Rice blast; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae Proteins - genetics; Signs and symptoms; Sporulation; Symptoms; Transcription; Virulence; Virulence - genetics; Virulence - physiology; 생물학
• ISSN: 1225-8873; 1976-3794
• DOI: 10.1007/s12275-019-9363-5

Histone acetylation/deacetylation represent a general and efficient epigenetic mechanism through which fungal cells control gene expression. Here we report developmental requirement of MoHOS2-mediated histone deacetylation (HDAC) for the rice blast fungus, Magnaporthe oryzae . Structural similarity and nuclear localization indicated that MoHOS2 is an ortholog of Saccharomyces cerevisiae Hos2, which is a member of class I histone deacetylases and subunit of Set3 complex. Deletion of MoHOS2 led to 25% reduction in HDAC activity, compared to the wild-type, confirming that it is a bona-fide HDAC. Lack of MoHOS2 caused decrease in radial growth and impinged dramatically on asexual sporulation. Such reduction in HDAC activity and phenotypic defects of Δ Mohos2 were recapitulated by a single amino acid change in conserved motif that is known to be important for HDAC activity. Expression analysis revealed up-regulation of MoHOS2 and concomitant down-regulation of some of the key genes involved in asexual reproduction under sporulation-promoting condition. In addition, the deletion mutant exhibited defect in appressorium formation from both germ tube tip and hyphae. As a result, Δ Mohos2 was not able to cause disease symptoms. Wound-inoculation showed that the mutant is compromised in its ability to grow inside host plants as well. We found that some of ROS detoxifying genes and known effector genes are de-regulated in the mutant. Taken together, our data suggest that MoHOS2-dependent histone deacetylation is pivotal for proper timing and induction of transcription of the genes that coordinate developmental changes and host infection in M. oryzae .