title: A Cdc42 ortholog is required for penetration and virulence of Magnaporthe grisea.
abstract: Cdc42, a member of the Rho-family small GTP-binding proteins, is a pivotal signaling switch that cycles between active GTP-bound and inactive GDP-bound forms, controlling actin cytoskeleton organization and cell polarity. In this report, we show that MgCdc42, a Cdc42 ortholog in Magnaporthe grisea, is required for its plant penetration. Consequently, the deletion mutants show dramatically decreased virulence to rice due to the arrest of penetration and infectious growth, which may be attributed to the defect of turgor and superoxide generation during the appressorial development in Mgcdc42 deletion mutants. In addition, the mutants also exhibit pleotropic defects including gherkin-shaped conidia, delayed germination as well as decreased sporulation. Furthermore, dominant negative mutation leads to a similar phenotype to that of the deletion mutants, lending further support to the conclusion that MgCdc42 is required for the penetration and virulence of M. grisea.
authors.affiliation: The Key Laboratory for Bio-pesticide and Chemistry Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, PR China.
authors.forename: Wu
authors.initials: W
authors.lastname: Zheng
authors.forename: Zhiying
authors.initials: Z
authors.lastname: Zhao
authors.forename: Jisheng
authors.initials: J
authors.lastname: Chen
authors.forename: Wende
authors.initials: W
authors.lastname: Liu
authors.forename: Haiyan
authors.initials: H
authors.lastname: Ke
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.forename: Guodong
authors.initials: G
authors.lastname: Lu
authors.forename: Alan G
authors.initials: AG
authors.lastname: Darvill
authors.forename: Peter
authors.initials: P
authors.lastname: Albersheim
authors.forename: Shengcheng
authors.initials: S
authors.lastname: Wu
authors.forename: Zonghua
authors.initials: Z
authors.lastname: Wang
mesh_terms: D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D001467:Hordeum / Q000382:microbiology; D020082:Magnaporthe / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D012275:Oryza / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology*; D017384:Sequence Deletion; D014774:Virulence; D020764:cdc42 GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D020764:cdc42 GTP-Binding Protein