To better understand VIP functions, theMOMEVIP partners comprising six leading European laboratories and twointernational partners will develop new knowledge about the molecular andmetabolic bases of VIP biosynthesis and the functions of VIP in plantprotection. Plant volatile isoprenoids (isoprene,monoterpenes and sesquiterpenes, collectively hereafter called VIP) playcritical roles in communication with herbivores, defense against biotic andabiotic stresses, and modulation of stress-induced signaling molecules.
VIP are known to allow plants tocommunicate with other organisms, principally herbivores and their carnivoreenemies. But VIP also protect the photosynthetic apparatus against thermal andoxidative stresses. Transgenic plants that have been engineered to emitisoprene or monoterpenes, or in which isoprene biosynthesis has been repressedhave confirmed that isoprene emitters are more resistant to heat stress.Isoprene and monoterpenes reduce the damage caused by ozone and reactive oxygenspecies. In plants exposed to oxidative stresses isoprene quenches reactivenitrogen species (namely NO), which also have an important role as messengermolecules of the hypersensitive response to stress. The observation thatconstitutive VIP emission is not inhibited by stress conditions and that VIPare often induced by abiotic and biotic stresses, has therefore led to thehypothesis that a unique mechanism exists that is related to the antioxidantcapacity of VIP.
The MOMEVIP project will test currentmechanistic hypotheses on VIP functional roles using novel molecular andtechnological tools. In this way it will unravel cross-links between VIPbiosynthesis and other biochemical pathways, which may lead to changes in plantresistance to abiotic stressors and in
Improved mechanistic knowledge on VIPbiosynthesis will allow a better understanding of VIP functions, and a fullytargeted improvement of plant capacity to cope with biotic and abioticstressors, now and in the future. The results will go far beyond the scope ofMOMEVIP and will also help to improve metabolic engineering of plants for theproduction of economically interesting metabolites. Because VIP have a range ofother important functions in the interactions within the biosphere and betweenbiosphere and atmosphere, MOMEVIP advanced mechanistic knowledge will be of useto explain patterns of emission and to build predictive models of VIP emissionand reactivity in the atmosphere.