Release of moth pheromone compounds from Nicotiana benthamiana upon transient expression of heterologous biosynthetic genes

Abstract

Background Using genetically modified plants as natural dispensers of insect pheromones may eventually become part of a novel strategy for integrated pest management. Results In the present study, we first characterized essential functional genes for sex pheromone biosynthesis in the rice stem borer Chilo suppressalis (Walker) by heterologous expression in Saccharomyces cerevisiae and Nicotiana benthamiana, including two desaturase genes CsupYPAQ and CsupKPSE and a reductase gene CsupFAR2. Subsequently, we co-expressed CsupYPAQ and CsupFAR2 together with the previously characterized moth desaturase Atr∆11 in N. benthamiana. This resulted in the production of (Z)-11-hexadecenol together with (Z)-11-hexadecenal, the major pheromone component of C. suppressalis. Both compounds were collected from the transformed N. benthamiana headspace volatiles using solid-phase microextraction. We finally added the expression of a yeast acetyltransferase gene ATF1 and could then confirm also (Z)-11-hexadecenyl acetate release from the plant. Conclusions Our results pave the way for stable transformation of plants to be used as biological pheromone sources in different pest control strategies.

Insect pest management with sex pheromone precursors from engineered oilseed plants

“…For example, a wheat variety was stably transformed to release (E)-β-farnesene, the alarm pheromone of many aphid pests, but the technology has not yet demonstrated to suppress or control aphid populations in the field 33 . Xia et al 34 . transiently modified the tobacco, Nicotiana benthamiana, to release a mixture of noctuid moth pheromone components, more specifically Z11-16:OH, Z11-16:OAc and Z11-16:Ald, in the laboratory, but the engineering of plants to release specific moth pheromone blends at efficacious ratios and biologically relevant doses in the field for successful mating disruption remains an outstanding challenge 34 .…”

“…Xia et al 34 . transiently modified the tobacco, Nicotiana benthamiana, to release a mixture of noctuid moth pheromone components, more specifically Z11-16:OH, Z11-16:OAc and Z11-16:Ald, in the laboratory, but the engineering of plants to release specific moth pheromone blends at efficacious ratios and biologically relevant doses in the field for successful mating disruption remains an outstanding challenge 34 . In contrast, pheromones derived from downstream processing of precursors from oil crops could easily replace conventionally produced synthetic pheromone used by formulators for pest control tools used in mating disruption and trapping programmes.…”

Tunable control of insect pheromone biosynthesis inNicotiana benthamiana

“…The genes encoding moth acetyltransferases involved in pheromone biosynthesis have not yet been identified and previous studies have employed either a plant enzyme, EaDAcT (Ding et al, 2014;Mateos-Fernández et al, 2021) or the yeast enzyme ScATF1 (Ding et al, 2016;Xia et al, 2022), with the latter producing more acetate. When comparing the activities of these enzymes we observed differences in the levels of product obtained from two yeast enzymes, ScATF1 and SpATf1-2, which differ at only one amino acid (Figure 1) Inducible gene expression systems are essential tools in metabolic engineering.…”

“…These provide novel ways to control yields via either transient expression or stable transgenesis and can be combined with further control mechanisms. For example, trichome-specific promoters have recently been shown to increase the release of pheromones from leaves (Xia et al, 2022), which might enable the utility of the transgenic plant itself as live dispensers, proposed as an alternative to extraction from harvested biomass for use in traditional dispensers (Mateos Fernández et al, 2022). Finally, the regulatory systems demonstrated here and developed as modular genetic elements for facile reuse, are not limited to controlling pheromone biosynthesis, but are broadly useful to the design of constructs for plant metabolic engineering.…”

Transcriptional deregulation of stress-growth balance in Nicotiana benthamiana biofactories producing insect sex pheromones

“…Sustainable production of insect sex pheromones in plant biofactories is currently an emerging topic in plant biotechnology ( Xia et al., 2021 ; Mateos Fernández et al., 2022 ; Xia et al., 2022 ). Sexy Plant, a transgenic N. benthamiana moth pheromone biofactory, is a bioproduction platform with a constitutive expression of an entire moth sex pheromone biosynthetic pathway, producing and emitting the desired final products ( Mateos-Fernández et al., 2021 ).…”