A novel MAP kinase-interacting protein MoSmi1 regulates development and pathogenicity in Magnaporthe oryzae

Area of Science:

• Mycology
• Molecular Biology
• Plant Pathology

Background:

• The fungal cell wall is vital for maintaining physiological functions and resisting external stress.
• MoNap1, a nucleosome assembly protein in Magnaporthe oryzae, influences cell wall integrity (CWI), stress response, and pathogenicity.
• MoNap1 negatively regulates the expression of MoSMI1.

Purpose of the Study:

• To investigate the function of MoSMI1 in Magnaporthe oryzae.
• To elucidate the role of MoSmi1 in regulating cell wall integrity, development, and pathogenicity.
• To understand the molecular mechanisms underlying MoSmi1's function, particularly its interaction with signaling pathways.

Main Methods:

• Gene deletion of MoSMI1 in Magnaporthe oryzae.
• Analysis of appressorium function, cell morphology, and pathogenicity in MoSMI1 deletion mutants.
• Protein interaction studies (MoSmi1 with MoOsm1 and MoMps1).
• Phosphorylation level analysis of key MAPK pathway components (MoOsm1, MoMps1, MoPmk1).
• Transcriptome analysis to identify regulated processes.

Main Results:

• Deletion of MoSMI1 caused significant defects in appressorium function, CWI, cell morphology, and pathogenicity.
• MoSmi1 interacts with MoOsm1 and MoMps1, affecting the phosphorylation of MoOsm1, MoMps1, and MoPmk1.
• Transcriptome data indicated MoSmi1 regulates membrane-related pathways and oxidation-reduction processes.
• MoSmi1 plays a critical role in mediating the mitogen-activated protein kinase (MAPK) signaling pathway.

Conclusions:

• MoSmi1 is essential for maintaining cell wall integrity and pathogenicity in Magnaporthe oryzae.
• MoSmi1 regulates CWI and fungal development by mediating the MAPK signaling pathway.
• The findings highlight MoSmi1 as a key regulator of infection-related processes in M. oryzae.