P-175 - Identification and Characterization of Global Penetration Regulator in Plant Pathogenic Fungi

Pathogenic fungi encounter intricate host defense systems, prompting genetic mechanisms that modulate their growth and development for successful survival and proliferation within the host, particularly during infection. These mechanisms entail multifaceted and complex processes that require spatiotemporal regulation of various genes. In this study, we focused on transcription factors (TFs) involved in the initial plant penetration, directly affecting the virulence of plant pathogenic fungus F. graminearum. Notably, Fusarium graminearum Defective In Penetration 1 (FgDIP1) knockout mutants exhibited only minor growth defects but were unable to penetrate the hard-to-degrade nitrocellulose membrane, thus earmarking it as a potential penetration regulator. To identify gene candidates directly involved in the penetration process, transcriptomic analysis was conducted under penetration-mimicking conditions using a nitrocellulose membrane. Gene ontology (GO) analysis revealed that these penetration-related gene candidates are associated with the membrane transport system. In addition, ChIP-seq analysis revealed that FgDIP1 is a key regulator of the Ino80 complex. Interestingly, we identified putative regulons of FgTF51 that may influence the physical penetration process in F. graminearum. This study will expand our understanding of the molecular mechanisms underpinning plant infection processes and the pivotal regulators associated with fungal pathogenicity.