Peroxisome Proliferator Agent Of Rice Blast Fungus And Pex11 Gene Family Bioinformatics Research

Peroxisomes play vital roles in fungal pathogenicity. Peroxisomal proliferators are chemicals which induced Peroxisomal proliferation in mammalian cells. In plant pathogenic fungi, very little was known on the peroxisome proliferation and gene regulation mechanisms involved. In this work, the effects of peroxisomal proliferators to Magnaporthe oryzae, a model plant pathogenic fungus, were investigated. We analyzed the growth and development of the fungus influenced by the peroxisomal proliferators to, the proliferation in its spores induced, and as well the expression of peroxisomal proliferation genes. PEX11genes are key regulators in peroxisomal proliferation. To investigate the mechanism of peroxisomal proliferation in filamentous fungi, we analyzed PEX11gene family members by bioinformatics methods. This study is helpful to further research on function and peroxisomal proliferation and will probably benefit the research of fungal pathogenesis and rice blast control.Firstly, the effects of6typical peroxisomal proliferators to vegetative growth, spore germination, appressorium formation and pathogenicity of wild-type M. oryzae Guy11were investigated. Then, by using the red fluorescent protein (RFP) labeling strategy, the Peroxisomal proliferation were compared in the spores treated by the peroxisomal proliferators and those untreated. Finally, we used the Real time PCR technique to detect the expression levels of3PEX genes which are probably related to peroxisomal proliferation in treated and untreated mycelia. As the results, all6peroxisomal proliferators inhibited vegetative growth, germination and pathogenicity of M. oiyzae in different levels. In certain concentration, each of the peroxisome proliferators caused lower development of M. oryzea, and this inhibition was strengthened gradually along with concentration increasing. All the peroxisomal proliferators induced the peroxisomal proliferation significantly in the spores. And the relative expression levels of the selected PEX genes were improved by the peroxisomal proliferators.For bioinformatics research of PEX11family, we retrieved the PEX11gene family members in26kinds of representative fungi, predicted the gene structure and protein structure and analyzed the conserved sequence. As the result,66Pexllp candidates of PEX11gene family from the26fungal species were obtained and analyzed. In most filamentous fungi,2or3potential Pexl lps were found, in contrast with1or2in yeast species. Compared with other fungal species, the Ascomycetes tend to have more Pexl lps, and even5in several individuals. The data of phylogenetic analysis and protein structure indicated that all of the Pexl lps were divided into3groups:Ⅰ,Ⅱ, and Ⅲ. The members of group Ⅰ and group Ⅲ existed in most species, while those in group Ⅱ were found only in Pezizomycotina. PEX11gene contains0-6introns with different sizes and phases. By MEME analysis,5-6conserved motifs were found in each Pexllps. Among them, motif8in C-terminal was most conserved, and thus maybe played a vital role in maintaining the proper function of Pexllp.