MoPtc6, a Type 2C Protein Phosphatase Plays Critical Roles in the Development and Virulence of <i>Magnaporthe oryzae</i>

Rice blast caused by Magnaporthe oryzae pathotype is the worst disease that leads to serious food insecurity globally. Understanding rice blast disease pathogenesis is therefore essential for development of blast disease mitigation strategy. Reverse phosphorylation mediated by phosphatases perform a vital function in the activation of diverse biological mechanisms within eukaryotic. However, little has been reported on the roles of PP2Cs in the virulence of blast fungus. In this current work, we deployed functional genomics and biochemical approach to characterize type 2C protein phosphatase MoPtc6 in blast fungus. Deletion of MoPTC6 led to drastic reduction in conidiophore development, conidia production, hyphal growth, and stresses tolerance. Western blotting assay demonstrated that phosphorylation level of MoOsm1 was decreased while MoMps1 was increased in the MoPtc6 deletion mutant, comparative transcriptome assay revealed higher number of expressed genes between mutant and wild type. Localization assay confirmed that MoPtc6 is sub localized in the cytoplasm of mycelia, spores, and in the appressoria of M. oryzae. Furthermore, disruption of MoPTC6 impaired appressoria turgor pressure and glycogen utilization; more findings revealed attenuation of hyphal penetration and virulence upon deletion of MoPTC6. Generally, present findings suggested the role of MoPtc6 in the growth and virulence of M. oryzae.