Karrikin signaling in arbuscular mycorrhiza development
C. GUTJAHR (1), S. Carbonnel (1), V. Basso (1), M. Kolodzijei (1), T. Wang (2) (1) LMU Munich, Faculty of Biology Genetics, Germany; (2) John Innes Center, Metabolic Biology, United Kingdom

Arbuscular mycorrhiza (AM) symbioses are ancient and widespread in the plant kingdom and are based on the exchange of nutrients. The fungus provides minerals (most prominently phosphate) to the plant and receives organic carbon in return. Symbiosis establishment is initiated with an interchange of diffusible signaling molecules ensuring reciprocal recognition and promoting symbiosis-facilitating responses of both partners. We have recently shown that the rice alpha-beta hydrolase D14L participates in early recognition of AM fungi: a rice d14l mutant is not colonized and is transcriptionally unresponsive to exudates from germinating fungal spores (Gutjahr et al. 2015, Science). D14L forms a receptor complex with the F-box protein MAX2 for the smoke compound karrikin, which induces germination of fire-following plants. Furthermore, this complex regulates seedling morphogenesis in Arabidopsis. We use the legume Lotus japonicus, which is permissive to rapid hairy root transformation, to study the molecular function and signaling downstream of the D14L-MAX2 complex that is relevant to symbiosis establishment. We will report on the characterization of Lotus karrikin receptor mutants, on structure-function analysis of D14L and the importance of signaling repressors in AM symbiosis.

Abstract Number: C1-2, P2-56
Session Type: Concurrent