Different Chitin Synthase Genes Are Required for Various Developmental and Plant Infection Processes in the Rice Blast Fungus Magnaporthe oryzae

• DOI: 10.1371/journal.ppat.1002526
• Publication Date: 2012-02-09T22:11:07Z
• Authors: Ling-An Kong; Jun Yang; Guo-Tian Li; Lin-Lu Qi; Yu-Jun Zhang; Chen-Fang Wang; Wen-Sheng Zhao; Jin-Rong Xu; You-Liang Peng
• Keywords: Appressorium; Chitin synthase; Magnaporthe; Germ tube; Conidiation; Pathogenic fungus

Chitin is a major component of fungal cell wall and synthesized by chitin synthases (Chs). Plant pathogenic fungi normally have multiple synthase genes. To determine their roles in development pathogenesis, we functionally characterized all seven CHS genes Magnaporthe oryzae. Three them, CHS1, CHS6, CHS7, were found to be important for plant infection. While the chs6 mutant was non-pathogenic, chs1 chs7 mutants significantly reduced virulence. CHS1 plays specific role conidiogenesis, an essential step natural infection cycle. Most conidia had no septum spore tip mucilage. The hyphal growth conidiation. It failed penetrate grow invasively cells. two MMD-containing genes, CHS5 similar expression pattern. Although deletion detectable phenotype, chs5 double more severe defects than mutant, indicating that they may overlapping functions maintaining polarized vegetative invasive hyphae. Unlike other CHS7 has unique function appressorium formation. it blocked formation germ tubes on artificial hydrophobic surfaces, still produced melanized appressoria tips or distinct impacts tube. also defective penetration growth. Overall, our results indicate individual play diverse growth, development, pathogenesis M. oryzae, provided potential new leads control this devastating pathogen targeting synthases.