Dual-RNA-sequencing to elucidate the interactions between sorghum and .

In warm and humid regions, the productivity of sorghum is significantly limited by the fungal hemibiotrophic pathogen , the causal agent of anthracnose, a problematic disease of sorghum ( (L.) Moench) that can result in grain and biomass yield losses of up to 50%. Despite available genomic resources of both the host and fungal pathogen, the molecular basis of sorghum- interactions are poorly understood. By employing a dual-RNA sequencing approach, the molecular crosstalk between sorghum and can be elucidated. In this study, we examined the transcriptomes of four resistant sorghum accessions from the sorghum association panel (SAP) at varying time points post-infection with . Approximately 0.3% and 93% of the reads mapped to the genomes of and , respectively. Expression profiling of versus at 1-, 3-, and 5-days post-infection (dpi) indicated that genes encoding secreted candidate effectors, carbohydrate-active enzymes (CAZymes), and membrane transporters increased in expression during the transition from the biotrophic to the necrotrophic phase (3 dpi). The hallmark of the pathogen-associated molecular pattern (PAMP)-triggered immunity in sorghum includes the production of reactive oxygen species (ROS) and phytoalexins. The majority of effector candidates secreted by were predicted to be localized in the host apoplast, where they could interfere with the PAMP-triggered immunity response, specifically in the host ROS signaling pathway. The genes encoding critical molecular factors influencing pathogenicity identified in this study are a useful resource for subsequent genetic experiments aimed at validating their contributions to pathogen virulence. This comprehensive study not only provides a better understanding of the biology of but also supports the long-term goal of developing resistant sorghum cultivars.