DFG Poplar Communication

Source: EUS

The project funded by DFG (SCHN653/5-2 2015-2018) is a cooperation between EUS and the Department of Forest Botany and Tree Physiology at the University of Göttingen. Here we aim to characterize the molecular and biochemical changes in Arabidopsis thaliana and Populus x canescens roots that promote lateral root (LR) formation in response to Laccaria bicolor scents and to search for putative receptors of the sesquiterpenes. Towards these goals we will address the following questions: Which molecular and biochemical events lead to LR growth stimulation downstream of the sesquiterpene signal? Which fungal VOCs, besides thujopsen, promote LR formation? How are the VOCs sensed and how is the signal transmitted?

To achieve these goals, we study the time-courses of the transcriptional, proteomic and metabolic responses down-stream the VOC stimulus during the establishment of the stimulated LR phenotype. Furthermore, we investigate ROS and Ca2+ as signaling mediators by employing transgenic and wildtype Arabidopsis and poplar lines. To identify further putative signaling sesquiterpenes in plant-fungal communication Laccaria bicolor sesquiterpene synthases are cloned and the individual sesquiterpene genes will be knocked out in Laccaria bicolor. The transformants will be tested in bioassays. The comparison of the transcriptomes of poplar and Arabidopsis will allow us to identify genes, whose expression levels are drastically altered in plants in response to VOC signaling. These genes could serve as markers for LR growth induction. The candidate genes will be used to create a marker gene-based Arabidopsis mutant library, which will be screened for terpene receptors and other components relevant in the communication/signaling.

Selected publications

Ditengou FM, Müller A, Rosenkranz M, Felten J, Lasok H, Miloradovic van Doorn M, Legué V, Palme K, Schnitzler JP, Polle A (2015) Volatile signaling by sesquiterpenes from ectomycorrhizal fungi reprogrammes root architecture. Nature Communications 6, 6:6279.

Müller A, Faubert P, Hagen M, zu Castell W, Polle A, Schnitzler J-P, Rosenkranz M (2013) Volatile profiles of fungi - Chemotyping of species and ecological functions. Fungal Genetics and Biology, 54, 25-33