Functional Analysis Of A Putative Paxillin In Magnaporthe Oryzae

Paxillin is a member of FAK protein family. As a scaffold protein, Paxillin contains multitude domain. Paxillin plays key role in development of many organisms. In mammal cells, Paxillin is involved in the regulation of polarity growth. In fission yeast, paxillin is a component of actomysin ring and functions to stabilize the actommysin ring during cytokinesis. Magnaporthe oryzae, the casuing pathogen fungus of rice blast disease, is a good model for study filamentous fungi. We supposed that paxillin can regulate infection process of Magnaporthe oryzae. In this study, we characterized the biological function of MoPaxillin and found MoPaxillin deletion mutants lost the ability of conidiation and their mycelial growth was dramatically delayed, exhibiting a little swollen in hyphal tips. The mutants completely lost the pathogenicity although it can still produce appressoria at the hyphal tips. We also analyzed the expression of MoPaxillin in three different stages of wild type strain and found MoPaxillin expressed less in the conidial stage than orther stages. We also found that the expression level of MoPaxillin increased six fold in MoRacl deletion mutants. In the strain with background of TpmA-GFP, we found MoPaxillin deletion can stablize the actin to help cytoskeleton reorganize.