Studies On The Mechanism Of PMT Protein Family Genes In Magnaporthe Oryzae During The Growth And Development

Rice blast is the destructive fungal disease in paddy,which causes massive grain losses every year.Its pathogenic fungus is Magnaporthe oryzae.Research and analysis of Magnaporthe oryzae growth and molecular mechanisms of disease has important significance to control the occurrence and prevalence.In recent years,the study of rice blast fungus at the molecular level has a rapid development,a large number of disease related genes have been found.Mannosyltransferase is the important catalyst in eukaryotic protein glycosylation,and plays an important role in the structure and multi-function of protein.This paper based on amino acid sequence of Saccharomyces cerevisiae,has found three pathogenesis-related genes in Magnaporthe oryzae.The three genes encode proteins belong to the PMT protein family.Phylogenetic tree analysis showed that amino acid sequence of the PMT protein family are highly conservative in fungi.According to the principle of homologous recombination,respectively build the corresponding gene knockout carrier,and import to wild type strains of rice blast fungus Guy11 through the method of protoplast transformation,respectively obtain the deletion mutants MoPMT1-7 and MoPMT1-8,MoPMT2-28 and MoPMT2-30,MoPMT4-9 and MoPMT4-22.Studies have shown that lack PMT genes,rice blast fungus conidium production decrease,abnormal morphology,the formation of appressorium is affected,pathogenic also decreases.Further study found that in the aspect of mycelial growth compare to the wild type strain,PMT deletion mutants has different degree of slowing down,and more sensitive to external stress factors;besides PMT deletion mutunts cell walls chitin contents is significantly reduced,integrity is destroyed.