Characterization And Functional Analysis Of Putative Chm1-regulatory Proteins In Magnaporthe Oryzae

Chml （one of the PAKs in Magnaporthe oryzae）, a homo log of ScCla4 （Cla4 in Saccharomyces cerevisiae）, has been demonstrated to involve in growth, conidiation, and appressorium formation. Further study finds that Chml can interact with MoRacl via its PBD domain, and genetically acts downstream of MoRacl to activate conidiogenesis. To further understand the MoRacl-Chml signaling pathway, the putative Chml-regulatory proteins were analyzed. ScCla4-interacting protein sequences were first used to BLAST against the M. oryzae genome database to retrieve their corresponding analogs and got three candidates including MoGvp36{MGG₀1508), MoZds2 （MGG₀3837） and MoBoi2（MGG₀7310）. First, expression patterns of their encoding genes in Δchml mutant were analyzed by qRT-PCR. The relatively expression of MoGvp36, MoZds2 and MoBoi2 were not obviously changed. Subsequently, gene-knock-out results revealed MoZds2 might involve in the vegetative growth and pathogenicity; MoBoi2 possible function in hyphae growth. However, yeast two-hybrid assay show that Chml could not intercat with MoGvp36 or MoBoi2. In addition, applying iTRAQ and RNA seq technology together to screen the differential expressed proteins and 45 genes were detected to change both on protein and RAN level in Δchml mutant, which will help better understanding MoRacl-Chml mediated conidiogenesis signaling in M. oryzae.