Importance of endocytic RabGTPases and endocytic recycling in virulence of the corn smut fungus Ustilago maydis

• Applicant: Dr. Nina-Alexandra Lehr
• Subject Area: Plant Cell and Developmental Biology
• Term: from 2009 to 2011
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 145102005

Endocytosis is essential for hyphal growth and recent results indicate that early endosomes contribute to fungal virulence in the plant pathogen U. maydis. The present proposal aims to elucidate the molecular mechanism by which endocytosis supports plant infection in the fungus U. maydis.Making use of a broad spectrum of techniques, including molecular genetics, live cell imaging and existing conditional mutants, the project will focus on 4 main objectives: (1) Endocytosis and recycling of the pheromone receptor Pra1 will be visualized using fluorescent ligands. In addition, recycling of the chitin synthase 8 (Msc1) will be analysed. (2) Preliminary data suggest the existence of a Rab11positive recycling compartment. The existence of such a compartment in filamentous fungi is unknown and will be confirmed. (3) The role of Rab4and Rab11like GTPases in endocytic recycling will be investigated. (4) Finally, temperaturesensitive Rab11 mutant strains will be generated that will be used in maize plant infection assays in order to obtain insight into the importance of endocytic recycling in fungal growth and pathogenicity.

• DFG Programme: Research Fellowships
• International Connection: Switzerland, United Kingdom
• Host: Professor Dr. Gero Steinberg
• Cooperation Partners: Professor Dr. Kai Johnsson; Dr. Mark E. Wood