Present addresses: Department of Biology, Western Washington University, 516 High Street, Bellingham, WA 98225, USA;
Reciprocal oxylipin-mediated cross-talk in the Aspergillus–seed pathosystem
Article first published online: 18 DEC 2007
Volume 67, Issue 2, pages 378–391, January 2008
How to Cite
Brodhagen, M., Tsitsigiannis, D. I., Hornung, E., Goebel, C., Feussner, I. and Keller, N. P. (2008), Reciprocal oxylipin-mediated cross-talk in the Aspergillus–seed pathosystem. Molecular Microbiology, 67: 378–391. doi: 10.1111/j.1365-2958.2007.06045.x
- Issue published online: 18 DEC 2007
- Article first published online: 18 DEC 2007
- Accepted 5 November, 2007.
In Aspergilli, mycotoxin production and sporulation are governed, in part, by endogenous oxylipins (oxygenated, polyunsaturated fatty acids and metabolites derived therefrom). In Aspergillus nidulans, oxylipins are synthesized by the dioxygenase enzymes PpoA, PpoB and PpoC. Structurally similar oxylipins are synthesized in seeds via the action of lipoxygenase (LOX) enzymes. Previous reports have shown that exogenous application of seed oxylipins to Aspergillus cultures alters sporulation and mycotoxin production. Herein, we explored whether a plant oxylipin biosynthetic gene (ZmLOX3) could substitute functionally for A. nidulans ppo genes. We engineered ZmLOX3 into wild-type A. nidulans, and into a ΔppoAC strain that was reduced in production of oxylipins, conidia and the mycotoxin sterigmatocystin. ZmLOX3 expression increased production of conidia and sterigmatocystin in both backgrounds. We additionally explored whether A. nidulans oxylipins affect seed LOX gene expression during Aspergillus colonization. We observed that peanut seed pnlox2–3 expression was decreased when infected by A. nidulansΔppo mutants compared with infection by wild type. This result provides genetic evidence that fungal oxylipins are involved in plant LOX gene expression changes, leading to possible alterations in the fungal/host interaction. This report provides the first genetic evidence for reciprocal oxylipin cross-talk in the Aspergillus–seed pathosystem.