Aug 2026· Journal of Fungi· Vol 12· 0 citations· 28 references
Medicine
Abstract
The SUN family protein MoSun4 in Magnaporthe oryzae has been previously implicated in mitophagy and has potential as a target for reducing rice blast, but its role as a secreted protein remains poorly understood. In this study, signal peptide prediction and yeast secretion assays confirmed MoSun4 signal peptide function, and co-localization revealed the localization of the extra-invasive hyphal membrane (EIHM)-associated apoplastic compartment or matrix, establishing MoSun4 as a secreted protein. In addition, deletion of the MoSUN4 gene reduced the hyphal growth, conidiation and virulence of M. oryzae. We further showed that MoSun4 is involved in regulating the expression of virulence-related genes, including multiple genes involved in cell wall degradation (eglC, eglD), secondary metabolism (gliK), and melanin biosynthesis (SDH1, BUF1, Cmr1, ALB1). Collectively, our study reveals that MoSun4 is a secreted protein that contributes to pathogenicity and is associated with altered expression of virulence-related genes, providing new insights into the functions of SUN family proteins.
Highlights This VdPRMT1 is a conserved arginine methyltransferase in Verticillium dahliae. VdPRMT1 contributes to fungal growth, stress adaptation, carbon utilization, and virulence. HIGS-mediated silencing of VdPRMT1 reduces Verticillium wilt severity in cotton. VdPRMT1 interacts with VdLuc7, indicating a potential link to RNA processing. Abstract Protein arginine methyltransferases (PRMTs) are key regulators of diverse cellular processes in eukaryotes, including transcriptional regulation, RNA processing, signal transduction and DNA repair. However, the biological functions of PRMTs in Verticillium dahliae remain largely unexplored. In this study, we identified a PRMT1 homolog in V. dahliae. Targeted deletion of VdPRMT1 resulted in severely impaired hyphal growth, sporulation, stress responses and pathogenicity. Subcellular localization analysis showed that VdPRMT1 is distributed in both the nucleus and cytoplasm of hyphae. Host-induced gene silencing (HIGS) of VdPRMT1 in cotton significantly reduced disease severity, supporting its important role in pathogenicity. Furthermore, VdLuc7, a U1 snRNP-associated protein containing multiple RG/RGG motifs, was identified as a putative interacting partner of VdPRMT1 through yeast two-hybrid (Y2H) screening, bimolecular fluorescence complementation (BiFC) and luciferase complementation imaging (LCI) assays. Together, our results demonstrate that VdPRMT1 is required for normal fungal development and full virulence in V. dahliae, and suggest that arginine methylation may contribute to pathogenicity through regulation of RNA processing-related pathways. These findings provide new insights into the molecular mechanisms underlying fungal virulence and identify VdPRMT1 as a potential target for disease control.
It is demonstrated that AaAtg4 is important for spore germination, siderophore biosynthesis, iron acquisition, oxidative stress resistance, and toxin production, thereby establishing its critical role in A. alternata virulence.
Hsin-Yu Lu, C. H. Y. Choo, Je-Jia Wu et al.· Fungal Genetics and Biology· 0 citations
A physical interaction is identified between AaSlt2 and Swi6/RlmA, suggesting that these components are critical for cell wall synthesis, which advances the understanding of pathogenic mechanisms of A. alternata and proposes potential strategies for controlling postharvest diseases.
Rong Li, Yiyang Liu, Li Li et al.· Virulence· 0 citations
It is demonstrated that MrFTRP1 exerts a dual-regulatory functioning as a positive regulator of conidiation and pathogenesis but a negative regulator of environmental stress tolerance, which expands the understanding of the regulatory diversity within the C6 TF family and identifies him as a promising target for the genetic improvement of mycoinsecticides.
Chentian Jiang, Hao Wu, You-Gui Tong et al.· Journal of Invertebrate Path...· 0 citations
ABSTRACT Rice blast disease, a major global threat to staple crops, is caused by the ascomycete fungus Magnaporthe oryzae. This pathogen has complex mechanisms to invade rice, with mitochondrial function crucial for infection energy. Our study looks at the impact of Mrm1, a putative rRNA methyltransferase, on mitochondrial dynamics and pathogenicity of M. oryzae. Mrm1 deficiency delays appressorium formation and reduces turgor pressure for host penetration and infection hypha expansion. The N-terminal sequence of Mrm1, with a mitochondrial targeting sequence (MTS), is vital for its localization and function. Deletions cause impaired growth and lower pathogenicity. Deleting MRM1 leads to abnormal mitochondrial morphology, with more filamentous mitochondria during invasive growth, disrupting the balance of fission and fusion. This imbalance reduces the fungus’s infection ability. Furthermore, loss of Mrm1 alters the steady-state protein levels of mitochondrial dynamics regulators Dnm1 and Fzo1, likely through translational regulation, while their transcript abundances remain unchanged. In the absence of Mrm1, the levels of these proteins are significantly reduced. Our findings deepen the understanding of epitranscriptomic regulation in fungal pathogenicity and represent a potential candidate for future target-based intervention strategies, pending validation through chemical or genetic approaches.