The Interaction Of CK2 And Rho3 And Function Of The Several Putative Rho3 Interacting Proteins In Magnaporthe Oryzae

Rice blast fungus, Magnaporthe oryzae, is an important model organism for the study of fungal growth, development, pathogenic mechanism and the interaction between host plant and pathogenic fungus.Protein kinase CK2 that has been found in all eukaryotic organisms is a conserved serine/threonine kinase that typically consists of two catalytic subunits and two regulatory subunitsin a tetrameric complexes. The catalytic subunit of CK2 is encoded by gene MGG₀3696; the two regulatory subunits are encoded by genes MGG₀0446 and MGG₀5651. Deletion mutants of these two regulatory subunits have a defect phenotype in the vegetative growth, sporulation and pathogenicity; but the catalytic subunit deletion mutant is lethal.Predictive analysis of bio-informatics showed that there is an obvious interaction phenomenon between CK2 and MoRho3 and the yeast two hybrid has proved the conclusion. The experiment is needed to be done to detect whether the interaction is also existed in the CK2 and other small G proteins Racl,Cdc42, Rhol, Rho2 and Rho4, but this interaction phenomenon among them is not obvious. At the same time we used the qRT-PCR method to detect the relative expression of three subunits of CK2 in MoRho3 mutant. The results showed that there is a upregulated expression in every subunit. These results proclaim that there is a complex relation between CK2 and MoRho3.We further determined function of some putative MoRho3 interacting proteins MGG₁1744, MGG₀1279 and MGG₁1243 through bio-informatics. We got the mutants of these three genes and analyzed their phenotypes. Taking together, our study reveals a more profound network of MoRho3-mediated signal transduction and provides the theoretical basis for the study of pathogenic mechanism in the M. oryzae.