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Ding, B.-J.

Publications and source records attributed to Ding, B.-J..

5 recordsLinked to original sources

Reconstruction of a rare {triangleup}10 desaturation pathway enables production of yellow peach moth pheromone precursors in Camelina sativa

Sex pheromones are environmentally friendly alternatives to traditional insecticides for pest control. The high synthesis cost, however, has restricted large-scale application. Plant-based biofactories provide a promising, sustainable route for cost-effective production that could facilitate the broader use of pheromone-based pest control. Mating disruption of the yellow peach moth, Conogethes punctiferalis--a serious pest of fruit trees and field crops in East Asia--can be achieved using (E)-10-hexadecenal and (Z)-10-hexadecenal, two components of its sex pheromone. To enable rational reconstruction of the biosynthetic pathway towards these unusual fatty acid derivatives in heterologous production systems, we first elucidated their biosynthesis by combining in vivo labeling experiments, transcriptomics and functional characterization of candidate desaturase and reductase genes using Nicotiana benthamiana and yeast expression systems. We identified a rare {Delta}10 fatty acyl desaturase that catalyzes the production of both (E)-10- and (Z)-10-hexadecenoic acids, along with a downstream fatty acyl reductase with higher activity on the E isomer. We further introduced this {Delta}10 desaturase together with an acyl-ACP thioesterase-1 into Camelina sativa to redirect seed lipid metabolism towards the accumulation of the pheromone precursor fatty acids. After four generations of selection, we obtained stably inherited Camelina lines accumulating up to 4.7% of target fatty acids in total seed lipids, with individual seeds containing up to 8.3 g, without significant effects on plant growth or seed viability. These findings demonstrate how elucidating moth pheromone biosynthetic pathways can support the development of sustainable biotechnological production systems for pheromone-based pest management.

synthetic biology↗

Paving the way for plant-based bioproduction of (Z)-13-octadecenoic moth pheromone compounds

Sex pheromones are eco-friendly agents to control pest insects. Yet, the cost of synthetic pheromone production has restricted their use essentially to high value crops. Plant-based bioproduction of pheromone compounds offers a promising and sustainable alternative, opening up for the deployment of pheromone-mediated pest control also in row crops. The rice leaffolder Cnaphalocrocis medinalis uses C18 pheromone compounds and is a major rice pest in South China. We demonstrate that the fatty acid precursor of the main C18 pheromone component of C. medinalis, (Z)-13-octadecenal, can be biotechnologically produced using the oilseed crop Camelina sativa. First, we used deuterium-labelling to establish an elongation-based pathway for pheromone precursor formation from hexadecanoic (palmitic) acid via desaturation to (Z)-11-hexadecenoic acid and elongation to (Z)-13-octadecenoic acid. Using transient expression in Nicotiana benthamiana, we identified a minimal pathway consisting of a {Delta}11 desaturase (CmedDES1), an elongase (CmedELO1), and a fatty acyl reductase (CmedFAR2) for the heterologous biosynthesis of long-chain pheromone monounsaturated C18 precursors in planta. Co-expression of the insect desaturases CmedDES1 or CsupYPAQ with the Camelina elongase CsaKCS1 in Nicotiana benthamiana resulted in higher production of Z13-18 products compared to co-expression with insect elongases. We finally engineered Camelina sativa seeds through seed-specific co-expression of the Z11-16-forming insect desaturase CsupYPAQ and CsaKCS1 elongase, enabling the accumulation of C18 fatty acid pheromone precursors. Our study paves the way for sustainable production of the sex pheromone of C. medinalis and other C18 monounsaturated pheromone precursors for crop protection.

synthetic biology↗

Making Plants Smell Like Moths: Nicotiana benthamiana release moth pheromone alcohol, aldehyde and acetate upon transient expression of biosynthetic genes of different origin

Using genetically modified plants as natural dispensers of insect pheromones may eventually become part of a novel strategy for integrated pest management. 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{Delta}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. Our results pave the way for stable transformation of plants to be used as biological pheromone sources in different pest control strategies.

bioengineering↗

Evolution of the Codling Moth Pheromone Through the Member of an Ancient Desaturase Expansion

Defining the origin of genetic novelty is central to our understanding of the evolution of novel traits. Diversification among fatty acid desaturase (FAD) genes has played a fundamental role in the introduction of structural variation in fatty acyl derivatives. Because of its central role in generating diversity in insect semiochemicals, the FAD gene family has become a model to study how gene family expansions can contribute to the evolution of lineage-specific innovations. Here we used the codling moth (Cydia pomonella) as a study system to decipher the proximate mechanism underlying the production of the {Delta}8{Delta}10 signature structure of Olethreutine moths. Biosynthesis of the codling moth sex pheromone, (E8,E10)-dodecadienol (codlemone), involves two consecutive desaturation steps, the first of which is unusual in that it generates an E9 unsaturation. The second step is also atypical: it generates a conjugated diene system from the E9 monoene C12 intermediate via 1,4-desaturation. Here we describe the characterization of the FAD gene acting in codlemone biosynthesis. We identify 27 FAD genes corresponding to the various functional classes identified in Insects and Lepidoptera. These genes are distributed across the C. pomonella genome in tandem arrays or isolated genes, indicating that the FAD repertoire consists of both ancient and recent duplications and expansions. Using transcriptomics, we show large divergence in expression domains: some genes appear ubiquitously expressed across tissue and developmental stages; others appear more restricted in their expression pattern. Functional assays using heterologous expression systems reveal that one gene, Cpo_CPRQ, which is prominently and exclusively expressed in the female pheromone gland, encodes an FAD that possesses both E9 and {Delta}8{Delta}10-desaturation activities. Phylogenetically, Cpo_CPRQ clusters within the Lepidoptera-specific {Delta}10/{Delta}11 clade of FADs, a classic reservoir of unusual desaturase activities in moths. Our integrative approach shows that the evolution of the signature pheromone structure of Olethreutine moths relied on a gene belonging to an ancient gene expansion. Members of other expanded FAD subfamilies do not appear to play a role in chemical communication. This advises for caution when postulating the consequences of lineage-specific expansions based on genomics alone.

evolutionary biology↗

Production of moth sex pheromones for pest control by yeast fermentation

The use of insect sex pheromones is an alternative technology for pest control in agriculture and forestry, which, in contrast to insecticides, does not have adverse effects on human health or environment and is efficient also against insecticide-resistant insect populations.1,2 Due to the high cost of chemically synthesized pheromones, mating disruption applications are currently primarily targeting higher value crops, such as fruits.3 Here we demonstrate a biotechnological method for the production of pheromones of economically important moth pests using engineered yeast cell factories. Biosynthetic pathways towards several pheromones or their precursors were reconstructed in the oleaginous yeast Yarrowia lipolytica, which was further metabolically engineered for improved pheromone biosynthesis by decreasing fatty alcohol degradation and downregulating storage lipid accumulation. The sex pheromone of the cotton bollworm Helicoverpa armigera was produced by oxidation of fermented fatty alcohols into corresponding aldehydes. The resulting pheromone was just as efficient and specific for trapping of H. armigera male moths in cotton fields in Greece as a synthetic pheromone mixture. We further demonstrated the production of the main pheromone component of the fall armyworm Spodoptera frugiperda. Our work describes a biotech platform for the production of commercially relevant titres of moth pheromones for pest control by yeast fermentation. Significance statementAgriculture largely relies on insecticides and genetically modified crops for pest control, however alternative solutions are required due to emerging resistance, toxicity and regulatory issues, and consumer preferences. Mating disruption with sex pheromones that act by preventing insect reproduction is considered the most promising and scalable alternative to insecticides. This method is highly efficient and safe for human health and environment. The likelihood of insect resistance development is very low and can be handled by adjusting the pheromone composition. The high cost of chemically synthesized pheromones is the major barrier for the wider adoption of pheromones. A novel method based on yeast fermentation enables the production of insect sex pheromones as a lower cost from renewable feedstocks.

bioengineering↗