LPMO-oxidized cellulose oligosaccharides evoke immunity in Arabidopsis conferring resistance towards necrotrophic fungus B. cinerea

Commun Biol. 2021 Jun 11;4(1):727. doi: 10.1038/s42003-021-02226-7.

Abstract

Lytic Polysaccharide Monooxygenases (LPMOs) are powerful redox enzymes able to oxidatively cleave recalcitrant polysaccharides. Widely conserved across biological kingdoms, LPMOs of the AA9 family are deployed by phytopathogens to deconstruct cellulose polymers. In response, plants have evolved sophisticated mechanisms to sense cell wall damage and thus self-triggering Damage Triggered Immunity responses. Here, we show that Arabidopsis plants exposed to LPMO products triggered the innate immunity ultimately leading to increased resistance to the necrotrophic fungus Botrytis cinerea. We demonstrated that plants undergo a deep transcriptional reprogramming upon elicitation with AA9 derived cellulose- or cello-oligosaccharides (AA9_COS). To decipher the specific effects of native and oxidized LPMO-generated AA9_COS, a pairwise comparison with cellobiose, the smallest non-oxidized unit constituting cellulose, is presented. Moreover, we identified two leucine-rich repeat receptor-like kinases, namely STRESS INDUCED FACTOR 2 and 4, playing a crucial role in signaling the AA9_COS-dependent responses such as camalexin production. Furthermore, increased levels of ethylene, jasmonic and salicylic acid hormones, along with deposition of callose in the cell wall was observed. Collectively, our data reveal that LPMOs might play a crucial role in plant-pathogen interactions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / immunology*
  • Arabidopsis / metabolism
  • Arabidopsis / microbiology
  • Botrytis / immunology*
  • Cellulose / metabolism*
  • Disease Resistance
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Mixed Function Oxygenases / metabolism*
  • Mixed Function Oxygenases / physiology
  • Oligosaccharides / metabolism*
  • Oligosaccharides / physiology
  • Plant Diseases / immunology*
  • Plant Diseases / microbiology
  • Sordariales / metabolism

Substances

  • Oligosaccharides
  • Cellulose
  • Mixed Function Oxygenases

Supplementary concepts

  • Botrytis cinerea
  • Thermothielavioides terrestris