Impact of VOCs on Plant Internal ROS/RNS Signaling

Volatile terpenes, such as isoprene, mono- and sesquiterpenes, emitted under various environmental conditions by plants react very rapidly with reactive oxygen species (ROS, i.e. ozone and OH') in the atmosphere. Rising evidence indicates that these molecules - before becoming evaporated - also react intracellularly with ROS (e.g. H2O2) and reactive nitrogen species (RNS, i.e. NO) influencing lifetime and concentration of these plant internal signaling molecules. Although the contours of isoprenes' (similar to some monoterpenes) functioning in plants becomes more clearly, we are far away understanding the detailed mechanism. The present project makes use of existing transgenic Arabidopsis and poplar mutants altered in isoprene emission. With these lines we will answer the following questions: (i) Are the observed metabolic shifts in emitting vs. non-emitting plants due to changed C-allocation patterns or result from impairment of signaling cascades involving ROS/RNS intermediates? (i) Which role isoprene plays in plants' adaptation to abiotic stress, as i.e. drought, UV-B radiation, or chilling? (iii) Does isoprene emission in poplar contribute to priming (pre-adaptation) prior subsequent stress events?