title: A fungal pathogen secretes plant alkalinizing peptides to increase infection.
abstract: Plant infections caused by fungi are often associated with an increase in the pH of the surrounding host tissue(1). Extracellular alkalinization is thought to contribute to fungal pathogenesis, but the underlying mechanisms are poorly understood. Here, we show that the root-infecting fungus Fusarium oxysporum uses a functional homologue of the plant regulatory peptide RALF (rapid alkalinization factor)(2,3) to induce alkalinization and cause disease in plants. An upshift in extracellular pH promotes infectious growth of Fusarium by stimulating phosphorylation of a conserved mitogen-activated protein kinase essential for pathogenicity(4,5). Fungal mutants lacking a functional Fusarium (F)-RALF peptide failed to induce host alkalinization and showed markedly reduced virulence in tomato plants, while eliciting a strong host immune response. Arabidopsis plants lacking the receptor-like kinase FERONIA, which mediates the RALF-triggered alkalinization response(6), displayed enhanced resistance against Fusarium. RALF homologues are found across a number of phylogenetically distant groups of fungi, many of which infect plants. We propose that fungal pathogens use functional homologues of alkalinizing peptides found in their host plants to increase their infectious potential and suppress host immunity.
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: Sara
authors: S
authors: Masachis
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: David
authors: D
authors: Segorbe
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: David
authors: D
authors: Turrà
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: Mercedes
authors: M
authors: Leon-Ruiz
authors: Zentrum für Molekularbiologie der Pflanzen, University Tübingen, 72076 Tübingen, Germany.
authors: Ursula
authors: U
authors: Fürst
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: Mennat
authors: M
authors: El Ghalid
authors: Biosciences, University of Exeter, Exeter, EX4 4QD, UK.
authors: Guy
authors: G
authors: Leonard
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: Manuel S
authors: MS
authors: López-Berges
authors: Biosciences, University of Exeter, Exeter, EX4 4QD, UK.
authors: Thomas A
authors: TA
authors: Richards
authors: Zentrum für Molekularbiologie der Pflanzen, University Tübingen, 72076 Tübingen, Germany.
authors: Georg
authors: 0000-0002-6746-6185
authors: G
authors: Felix
authors: Departamento de Genética, Campus de Excelencia Internacional Agroalimentario ceiA3, Universidad de Córdoba, Córdoba, Spain.
authors: Antonio
authors: A
authors: Di Pietro
mesh_terms: D017360:Arabidopsis / Q000254:growth & development / Q000382:microbiology; D005656:Fungal Proteins / Q000378:metabolism*; D005670:Fusarium / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity*; D054884:Host-Pathogen Interactions; D006863:Hydrogen-Ion Concentration; D018551:Solanum lycopersicum / Q000254:growth & development / Q000382:microbiology*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010455:Peptides / Q000378:metabolism*; D010766:Phosphorylation; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology*
chemical_list: D005656:Fungal Proteins; D010455:Peptides; D020928:Mitogen-Activated Protein Kinases