We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Tryptophan-derived secondary metabolites in Arabidopsis thaliana confer non-host resistance to necrotrophic Plectosphaerella cucumerina fungi.
- Authors
Sanchez-Vallet, Andrea; Ramos, Brisa; Bednarek, Paweł; López, Gemma; Piślewska-Bednarek, Mariola; Schulze-Lefert, Paul; Molina, Antonio
- Abstract
A defence pathway contributing to non-host resistance to biotrophic fungi in Arabidopsis involves the synthesis and targeted delivery of the tryptophan (trp)-derived metabolites indol glucosinolates (IGs) and camalexin at pathogen contact sites. We have examined whether these metabolites are also rate-limiting for colonization by necrotrophic fungi. Inoculation of Arabidopsis with adapted or non-adapted isolates of the ascomycete Plectosphaerella cucumerina triggers the accumulation of trp-derived metabolites. We found that their depletion in cyp79B2 cyp79B3 mutants renders Arabidopsis fully susceptible to each of three tested non-adapted P. cucumerina isolates, and super-susceptible to an adapted P. cucumerina isolate. This assigns a key role to trp-derived secondary metabolites in limiting the growth of both non-adapted and adapted necrotrophic fungi. However, 4-methoxy-indol-3-ylmethylglucosinolate, which is generated by the P450 monooxygenase CYP81F2, and hydrolyzed by PEN2 myrosinase, together with the antimicrobial camalexin play a minor role in restricting the growth of the non-adapted necrotrophs. This contrasts with a major role of these two trp-derived phytochemicals in limiting invasive growth of non-adapted biotrophic powdery mildew fungi, thereby implying the existence of other unknown trp-derived metabolites in resistance responses to non-adapted necrotrophic P. cucumerina. Impaired defence to non-adapted P. cucumerina, but not to the non-adapted biotrophic fungus Erysiphe pisi, on cyp79B2 cyp79B3 plants is largely restored in the irx1 background, which shows a constitutive accumulation of antimicrobial peptides. Our findings imply differential contributions of antimicrobials in non-host resistance to necrotrophic and biotrophic pathogens.
- Subjects
METABOLITES; ARABIDOPSIS thaliana; TRYPTOPHAN; AMINO acids; PLANT physiology
- Publication
Plant Journal, 2010, Vol 63, Issue 1, p115
- ISSN
0960-7412
- Publication type
Article
- DOI
10.1111/j.1365-313X.2010.04224.x