Genetic Engineering of Terpenoid Metabolism Attracts Bodyguards to Arabidopsis

Abstract

Herbivore-damaged plants release complex mixtures of volatiles that attract natural enemies of the herbivore. To study the relevance of individual components of these mixtures for predator attraction, we manipulated herbivory-induced volatiles through genetic engineering. Metabolic engineering of terpenoids, which dominate the composition of many induced plant volatile bouquets, holds particular promise. By switching the subcellular localization of the introduced sesquiterpene synthase to the mitochondria, we obtained transgenic Arabidopsis thaliana plants emitting two new isoprenoids. These altered plants attracted carnivorous predatory mites (Phytoseiulus persimilis) that aid the plants' defense mechanisms.

Induction of a leaf specific geranylgeranyl pyrophosphate synthase and emission of (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene in tomato are dependent on both jasmonic acid and salicylic acid signaling pathways

“…Arabidopsis leaves placed in (E)-nerolidol and also untreated transgenic Arabidopsis plants expressing strawberry nerolidol synthase, are capable of producing DMNT (Kappers et al 2005). This is interesting since DMNT is normally not produced by Arabidopsis whereas TMTT is (Van Poecke et al 2001).…”

Herbivory-induced volatiles function as defenses increasing fitness of the native plant Nicotiana attenuata in nature

“…Thus the inducibility of HIPV emission, which ensures association with herbivore feeding, is likely essential for HIPV function, but it is difficult to engineer (Kos et al, 2009). Engineered constitutive HIPV emissions have been used, either on predators and parasitoids trained to associate target volatiles with prey in short-term laboratory experiments (Kappers et al, 2005; Schnee et al, 2006), or in set-ups in which target volatiles are always associated with prey (Rasmann et al, 2005; Degenhardt et al, 2009). When plants are engineered constitutively to emit HIPVs, they no longer provide accurate information about the location of feeding herbivores, and predators will not associate these signals with prey in nature.…”

Volatile terpenoids: multiple functions, biosynthesis, modulation and manipulation by genetic engineering

“…In the model plant Arabidopsis, females of parasitoids Cotesia marginiventris use TPS10 (a sesquiterpene) to track their lepidopteran host by utilizing the floral scent (Schnee et al 2006). Arabidopsis has been shown to emit two terpenoids, (3,S)-(E)-nerolidol and its derivative (E)-4,8-dimethyl-1,3,7-nonatriene, when the strawberry nerolidol synthase gene was introduced into the plants, resulting in greater attraction of the predators of predatory mites (Kappers et al 2005). Caryophyllene, emitted from the roots of Maize plants, is known to be an herbivore-induced below-ground signal, which strongly attracts entomopathogenic nematodes (Rasmann et al 2005;Delory et al 2016).…”

“…The most appropriate example is the accumulation of amorpha-4,11-diene (ADS) and FPS in plastids, resulting in approximately a 5000-fold increase in ADS concentration in model tobacco plants over another model plant (unchanged ADS gene) having a cytosolic gene product (Wu et al 2006). Likewise, a mitochondrial-localized heterologous TPS gene was first studied by Kappers et al (2005), which revealed that the overexpression of the FaNES1 gene from strawberry in the model Arabidopsis plant with an engineered 'Met' mitochondrial targeting sequence resulted in two new terpenoids involved in attracting predatory mites that potentially aid in defense against herbivores. The potential use of genetic engineering in the subcellular localization of TPS genes provides new insights for further investigation.…”

“…Therefore, high terpenoid accumulation levels have been found for volatiles emitted from engineered model plants. If the purpose of genetic engineering is to adapt to the trophic interaction of plants with respect to insects, then the terpenoid volatiles released from model plants can have constructive effects against disease resistance (Kappers et al 2005;Yu et al 2012). On the other hand, volatilization is undesirable if terpenoid collection is desired, which poses a strategic question for scientists.…”