title: Plant surface cues prime Ustilago maydis for biotrophic development.
abstract: Infection-related development of phytopathogenic fungi is initiated by sensing and responding to plant surface cues. This response can result in the formation of specialized infection structures, so-called appressoria. To unravel the program inducing filaments and appressoria in the biotrophic smut fungus Ustilago maydis, we exposed cells to a hydrophobic surface and the cutin monomer 16-hydroxy hexadecanoic acid. Genome-wide transcriptional profiling at the pre-penetration stage documented dramatic transcriptional changes in almost 20% of the genes. Comparisons with the U. maydis sho1 msb2 double mutant, lacking two putative sensors for plant surface cues, revealed that these plasma membrane receptors regulate a small subset of the surface cue-induced genes comprising mainly secreted proteins including potential plant cell wall degrading enzymes. Targeted gene deletion analysis ascribed a role to up-regulated GH51 and GH62 arabinofuranosidases during plant penetration. Among the sho1/msb2-dependently expressed genes were several secreted effectors that are essential for virulence. Our data also demonstrate specific effects on two transcription factors that redirect the transcriptional regulatory network towards appressorium formation and plant penetration. This shows that plant surface cues prime U. maydis for biotrophic development.
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Lanver
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Berndt
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Marie
authors.initials: M
authors.lastname: Tollot
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Vikram
authors.initials: V
authors.lastname: Naik
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute for Applied Biosciences, Department of Genetics, Karlsruhe, Germany.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Vranes
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Warmann
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Münch
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Rössel
authors.affiliation: Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany.
authors.forename: Regine
authors.initials: R
authors.lastname: Kahmann
mesh_terms: D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics; D015966:Gene Expression Regulation, Fungal / Q000502:physiology*; D055106:Genome-Wide Association Study; D008563:Membrane Lipids / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D013499:Surface Properties; D059467:Transcriptome / Q000502:physiology*; D014588:Ustilago / Q000235:genetics / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D008563:Membrane Lipids; C000521:cutin