The role of fungal NADPH oxidase complexes in differentiation and virulence

• Applicant: Professor Dr. Paul Tudzynski
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems ; Plant Physiology
• Term: from 2013 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 244519510

• Final Report Year: 2017

Final Report Abstract

During this final project phase we have made significant progress towards an understanding of the molecular mechanisms of fungal Nox signaling. We established a model for the composition in relation to function and localization of the two Nox complexes in Botrytis cinerea. We could substantiate the ER functions of the BcNoxA complex, by showing its strong physical and functional association with the ER-bound enzyme protein disulfide isomerase. In addition we confirmed the strong link between Ca signaling and Nox activity in this fungus. A pulldown approach using BcNoxB as bait yielded unexpected interaction partners: enzymes of a putative secondary metabolite gene cluster. Our analyses indicate that these enzymes form a complex which might be physically associated to the BcNoxB complex, suggesting a direct role of Nox (as electron donator?) in this biochemical pathway, a new and fascinating perspective. The B. cinerea Nox complexes are now one of the best understood fungal Nox systems, and the exciting results obtained in this last period and the available tools/mutants will be a very good basis to gain a deeper insight into the molecular mechanisms of Nox signaling and to answer the major remaining questions.

Publications

• (2016) BcIqg1, a fungal IQGAP homolog, interacts with NADPH oxidase, MAP kinase and Calcium signaling proteins, and regulates virulence and development in B.cinerea. Mol Microbiol 101(2), 281–298
  Marschall R, Tudzynski P
  
• (2016) Chasing stress signals – Exposure to extracellular stimuli differentially affects the redox state of cell compartments in the wild type and signaling mutants of Botrytis cinerea. Fungal Genet Biol 90:12-22
  Marschall R, Schumacher J, Siegmund U, Tudzynski P
  
• (2016) ROS in development and infection processes. Seminars in Cell and Developmental Biology 57, 138-146
  Marschall R, Tudzynski P
  
• (2016) Update on Nox function, site of action and regulation in Botrytis cinerea. Fungal Biology and Biotechnology 3/8
  Marschall R, Siegmund U, Burbank J, Tudzynski P
  
• (2017) The protein disulfide isomerase of Botrytis cinerea: An ER protein involved in protein folding and redox homeostasis influences NADPH oxidase signaling processes. Frontiers in Microbiology 8:960
  Marschall R, Tudzynski P