Investigating the mechanisms of fungal effector uptake by plant cells
L. LO PRESTI (1), S. Uszkoreit (1), T. Heimerl (2), R. Kahmann (1) (1) Max Planck Institute For Terrestrial Microbiology, Germany; (2) Philipps University Marburg, Germany

Successful colonization of plant tissue by pathogenic and non pathogenic microbes requires the deployment of secreted effectors that manipulate host defense responses and metabolism. Secreted effectors can either display their activity in the apoplast or translocate to host cells and function therein. While bacteria and nematodes inject effectors into plant cells via specialized secretion systems, the molecular mechanisms of effector delivery by fungi remain largely elusive. To classify fungal effectors according to their site of action we have established an uptake assay that is based on biotinylation as hallmark of uptake. Here we demonstrate translocation of a subset of effectors during colonization of maize plants by the fungal pathogen Ustilago maydis. We propose that the assay may provide a powerful tool to investigate the molecular basis of effector uptake not in the U. maydis-maize pathosystem but more generally in eukaryotic microbe-plant interaction systems which are amenable to reverse genetics. Moreover we will show that U. maydis produces extracellular structures which might be involved in the crosstalk between fungus and host.

Abstract Number: P7-188
Session Type: Poster