MoHG1 Regulates Fungal Development and Virulence in Magnaporthe oryzae

<i>Magnaporthe oryzae</i> causes rice blast disease, which threatens global rice production. The interaction between <i>M. oryzae</i> and rice is regarded as a classic model for studying the relationship between the pathogen and the host. In this study, we found a gene, <i>MoHG1</i>, regulating fungal development and virulence in <i>M. oryzae</i>. The ∆<i>Mohg1</i> mutants showed more sensitivity to cell wall integrity stressors and their cell wall is more easily degraded by enzymes. Moreover, a decreased content of chitin but higher contents of arabinose, sorbitol, lactose, rhamnose, and xylitol were found in the ∆<i>Mohg1</i> mutant. Combined with transcriptomic results, many genes in MAPK and sugar metabolism pathways are significantly regulated in the ∆<i>Mohg1</i> mutant. A hexokinase gene, <i>MGG_00623</i> was downregulated in ∆<i>Mohg1,</i> according to transcriptome results. We overexpressed <i>MGG_00623</i> in a ∆<i>Mohg1</i> mutant. The results showed that fungal growth and chitin contents in <i>MGG_00623</i>-overexpressing strains were restored significantly compared to the ∆<i>Mohg1</i> mutant. Furthermore, MoHG1 could interact with MGG_00623 directly through the yeast two-hybrid and BiFC. Overall, these results suggest that MoHG1 coordinating with hexokinase regulates fungal development and virulence by affecting chitin contents and cell wall integrity in <i>M. oryzae,</i> which provides a reference for studying the functions of <i>MoHG1</i>-like genes.