Role of reactive oxygen species (ROS) in MAPK-mediated chemotropism and infectious growth of the plant pathogenic fungus Fusarium oxysporum

• Applicant: Dr. Daniela Elisabeth Nordzieke
• Subject Area: Metabolism, Biochemistry and Genetics of Microorganisms ; General Genetics and Functional Genome Biology
• Term: from 2015 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 280327700

• Final Report Year: 2017

Final Report Abstract

Soil-inhabiting plant-interacting fungi such as the tomato pathogen Fusarium oxysporum are able to locate the roots of the host plant in the soil. Recently, it was shown that class III peroxidases secreted by roots function as stimuli to direct hyphal growth. Since peroxidases catalyze the reductive cleavage of hydrogen peroxide, the awardee examined in this project the role of fungal-derived hydrogen peroxide in peroxidase-triggered directed growth. She applied a combination of phenotypic assays, Western Blot analyses and microscopy approaches to provide new evidence that cooperative enzymatic activity of the fungal NADPH oxidase B complex and superoxide dismutases (SOD) provide hydrogen peroxide for the enzymatic activity of plant-derived peroxidases. This interplay results in activation of two fungal MAPK pathways. Further, she proposes that the tetraspanin Pls1 functions as a downstream target of peroxidase-mediated chemotropic signaling. Taken together, the results of this project provide new insights into the adaptation processes of plant-associated fungi allowing chemotropic detection of plant hosts.

Publications

• (2015) Interplay of MAPK and ROS signaling in chemotrophic growth of Fusarium oxysporum; 28th Fungal Genetics Conference and Fusarium Workshop, Asilomar, USA
  Dirschnabel D, Turrà D, Di Pietro A
  
• (2016) Hyphal chemotropism in fungal pathogenicity; Seminars in Cell & Developmental Biology 57:69-75
  Turrà D, Nordzieke D, Vitale S, El Ghalid M, Di Pietro A
  (See online at https://doi.org/10.1016/j.semcdb.2016.04.020)
• (2016) Link between ROS and MAPK signaling in peroxidase induced chemotropism of Fusarium oxysporum; Fusarium Workshop 2016, satellite meeting of the 13th European Conference on Fungal Genetics, Paris, France
  Nordzieke D
  
• (2016) The fungal NOX complex is required for chemotropic sensing of plant peroxidases; Interdisciplinary Forum on Virulence Mechanisms of Phyto- and Human-Pathogenic Fungi, Erlangen, Germany
  Nordzieke D