Transcriptome analysis and functional validation reveal a novel gene BcCGF1 that enhances fungal virulence by promoting infection‐related development and host penetration

摘要

Simultaneous transcriptome analyses of both host plants and pathogens, and functional validation of the identified differentially expressed genes (DEGs) allow us to better understand the mechanisms underlying their interactions. Here, we analyse the mixed transcriptome derived from (the causal agent of grey mould) infected tomato leaves at 24 hr after inoculation, a critical time point at which the pathogen has penetrated and developed in the leaf epidermis, whereas necrotic symptoms have not yet appeared. Our analyses identified a complex network of genes involved in the tomato– interaction. The expression of fungal transcripts encoding candidate effectors, enzymes for secondary metabolite biosynthesis, hormone and reactive oxygen species (ROS) production, and autophagy‐related proteins was up‐regulated, suggesting that these genes may be involved in the initial infection processes. Specifically, tomato genes involved in phytoalexin production, stress responses, ATP‐binding cassette transporters, pathogenesis‐related proteins, and WRKY DNA‐binding transcription factors were up‐regulated. We functionally investigated several DEGs via gene replacement and pathogenicity assays, and demonstrated that was a novel virulence‐associated factor that mediates fungal development and virulence via regulation of conidial germination, conidiation, infection structure formation, host penetration, and stress adaptation. The fungal infection‐related development was controlled by ‐mediated ROS production and exogenous cAMP restored the mutant infection‐related development. Our findings provide new insights into the elucidation of the simultaneous tactics of pathogen attack and host defence. Our systematic elucidation of in mediating fungal pathogenesis may open up new targets for fungal disease control.