Open AccessVirulence of the maize smut U stilago maydis is shaped by organ‐specific effectors
Author(s) -
Schilling Lena,
Matei Alexandra,
Redkar Amey,
Walbot Virginia,
Doehlemann Gunther
Publication year - 2014
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/mpp.12133
Subject(s) - ustilago , biology , virulence , effector , smut , gene , pathogen , fungus , primordium , microbiology and biotechnology , botany , genetics
Summary With the exception of U stilago maydis , smut fungi infecting monocotyledonous hosts systemically colonize infected plants and cause symptoms exclusively in the inflorescences. U stilago maydis infects primordia of all aerial organs of maize ( Z ea mays L .) and results in the formation of large plant tumours. Previously, we have found that U . maydis infection of seedling leaves, adult leaves and tassels causes organ‐specific transcriptional changes in both the pathogen and the host. Of particular interest, U . maydis genes encoding secreted proteins are differentially expressed depending on the colonized maize organ. Therefore, we hypothesized that the fungus secretes virulence‐related proteins (effectors) that act in an organ‐specific manner. Here, we present the identification and functional characterization of 20 presumptive organ‐specific U . maydis effector genes. U stilago maydis deletion strains for these genes were generated and tested for infectivity of maize seedling leaves and tassels. This approach identified 11 effector genes required for the full virulence of U . maydis. In nine cases, virulence was only affected in one of the tested plant organs. These results demonstrate that individual fungal effector proteins contribute to fungal virulence in an organ‐specific manner.