Open AccessActivation of the cAMP Pathway in Ustilago maydis Reduces Fungal Proliferation and Teliospore Formation in Plant Tumors
Author(s) -
Julia Krüger,
Gabriel Loubradou,
Gerhard Wanner,
Erika Regenfelder,
Michael Feldbrügge,
Regine Kahmann
Publication year - 2000
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi.2000.13.10.1034
Subject(s) - ustilago , biology , hypha , mutant , dikaryon , protein subunit , protein kinase a , microbiology and biotechnology , fungus , mating , mutation , fungal protein , kinase , botany , genetics , gene
In the corn smut fungus Ustilago maydis, mating of two haploid sporidia is a prerequisite for subsequent colonization of the host. Cyclic AMP (cAMP) and pheromone signals have been implicated in this developmental program. The cAMP pathway is also needed for subsequent fungal development in planta, as null mutants in any component of the pathway fail to form tumors. Here we show that moderate activation of the pathway conferred either by mutation in the Gα subunit or by mutation in the regulatory subunit of the protein kinase A influences tumor morphology. In the resulting tumors, the amount of fungal material is drastically reduced and fungal development is arrested at the stage of sporogenic hyphae. We conclude that tight regulation of the cAMP pathway is crucial for fungal development within the plant but does not interfere with the tumor induction process.