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Peroxisomes are cellular organelles present ubiquitously in eukaryotic cells and are involved in β-oxidation, glyoxylate cycle and a variety of biochemical metabolisms. Recently peroxisomes have been demonstrated to play vital roles in the host infection processes by plant fungal pathogens. The biogenesis of peroxisomes requires a category of proteins named peroxins, which are encoded by the PEX genes. So far, more than 10 PEX genes were isolated in phytopathogenic fungi, and significant research efforts are focused on the mechanism of peroxisome formation and the roles of peroxisome in the development and pathogenicity of fungal pathogens. In this review, we summarize the latest advances in peroxisome biogenesis and functions in pathogenic fungi, including the roles of PEXs in life cycle of peroxisome, peroxisome related metabolisms, and fungal development, infection and pathogenicity, in order to provide references for future studies in plant pathogenic fungi and the control of disease.

The family members of PEX11 are key factors involved in regulation of peroxisome proliferation. Sixty-six PEX11p candidates of PEX11 gene family from 26 representative fungal species were obtained and analyzed by bioinformatic strategies. In most filamentous fungi, 2 or 3 potential PEX11ps were found, in contrast with 1 or 2 in yeast species. Compared with other fungal species, the Ascomycetes tend to have more PEX11ps, and even 5 in several individuals. The data of phylogenetic analysis and protein structure indicated that all of the PEX11ps were divided into 3 groups: 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. By MEME analysis, 5-6 conserved motifs were found in each PEX11ps. Among them,motif 8 in C-terminal had the most conservation, indicating that this motif probably plays a key role in maintaining the proper function of PEX11p.

Rice blast, caused by the fungal pathogen Magnaporthe grisea, is one of the most devastating diseases of rice. The specific interaction between rice and M. grisea is an important model system for studying the host-pathogen interaction mechanisms. In this article, we summarized recent research progresses on avirulence genes, which are the most important effectors in M. grisea with the focus on chromosome mapping, cloning method, functional analysis, and evolution study of avirulence genes, and the possible hotspot of the research on avirulence genes in the future was also been discussed. This knowledge may shed a light on the molecular mechanism underlying avirulence genes function and the possible interaction relationship between the host and the pathogen.

Targeted gene replacement (TGR) is an important technique for gene function analysis. With the development of genome sequencing and transformation, TGR has been applied widely to filamentous fungi, and many new systems and approaches have been established. In this paper, strategies involved in TGR in filamentous fungi were reviewed, including transformation systems, targeting vector construction, mutant selection and so on. Compared with TGR, RNAi and other techniques of gene function analysis were introduced and reviewed as well.