Characterization of oxysterol binding protein homolog MgORP1 in therice blast fungus Magnaporthe grisea

Abstract:

[Objective] To study the component of ORPs (Oxysterol-binding proteins-related proteins) family in the rice fungus (Magnaporthe grisea), and the functions of MgORP1 gene with growing development of M. grisea, we constructed two MgORP1 deletion mutants and a complementation mutant. [Methods] All proteins of ORPs have a conserved OSBP-related ligand-binding domain (ORD), which was compared by BLASTP with the sequences of M. grisea genomic DNA published in M.grisea database. One of ORP gene, designated as MgORP1, was deleted by gene replacement and then the phenotypes of △MgORP1 were characterized. [Results] Six putative ORP family proteins have been found in M. grisea, and the growth rate of hyphal colony in complete medium and conidiation of △MgORP1 were lower, whereas the ability of conidia germination, appressoria formation and pathogenicity were normal. [Conclusion] MgORP1 gene of M.grisea was probably involved in colony growth and conidiation.