Identification of putative Type-I sex pheromone biosynthesis-related genes expressed in the female pheromone gland of Streltzoviella insularis

Abstract

Species-specific sex pheromones play key roles in moth sexual communication. Although the general pathway of Type-I sex pheromone biosynthesis is well established, only a handful of genes encoding enzymes involved in this pathway have been characterized. Streltzoviella insularis is a destructive wood-boring pest of many street trees in China, and the female sex pheromone of this species comprises a blend of (Z)-3-tetradecenyl acetate, (E)-3-tetradecenyl acetate, and (Z)-5-dodecenyl acetate. This organism therefore provides an excellent model for research on the diversity of genes and molecular mechanisms involved in pheromone production. Herein, we assembled the pheromone gland transcriptome of S. insularis by next-generation sequencing and identified 74 genes encoding candidate key enzymes involved in the fatty acid biosynthesis, β-oxidation, and functional group modification. In addition, tissue expression patterns further showed that an acetyl-CoA carboxylase and two desaturases were highly expressed in the pheromone glands compared with the other tissues, indicating possible roles in S. insularis sex pheromone biosynthesis. Finally, we proposed putative S. insularis biosynthetic pathways for sex pheromone components and highlighted candidate genes. Our findings lay a solid foundation for understanding the molecular mechanisms underpinning S. insularis sex pheromone biosynthesis, and provide potential targets for disrupting chemical communication that could assist the development of novel pest control methods.

Transcriptome analysis identifies candidate genes in the biosynthetic pathway of sex pheromones from a zygaenid moth, Achelura yunnanensis (Lepidoptera: Zygaenidae)

“…As one of the differences of gene numbers, it may be attributed to the sequencing depth of the PG transcriptomes, such as A. yunnanensis (47,632,610 clean reads), E. cautella (231, 851, 937 clean reads) ( Antony et al, 2015 ), S. litura (63,209,172 clean reads) ( Zhang et al, 2015 ), Maruca vitrata (119,454,916 clean reads) ( Cha et al, 2017 ) and A. segetum (53,235,252 clean reads) ( Ding & Lofstedt, 2015 ). In addition to that, the transcriptome sequencing and assembly of multi-tissues also facilitated the identification of the pheromone biosynthesis and degradation genes in the PGs, further supported by a broad tissue distribution of the pheromone biosynthesis genes in A. yunnanensis and other moth species ( Zhang et al, 2014b ; Xia et al, 2015 ; Yang, Tao & Zong, 2020 ). Except for the possible reasons mentioned above, we cannot exclude other possibilities such as the difference of sex pheromone components among species.…”

Developments in Fatty Acid-Derived Insect Pheromone Production Using Engineered Yeasts

“…Several other desaturases that catalyze double bond generation in saturated fatty acyl have been identified. For instance, in Streltzoviella insularis , Δ5 desaturases (Z5 and E5) catalyze the conversion of C16:CoA to (E/Z)5-C16:CoA, and Z9 desaturases catalyze the conversion of C16:CoA to Z9-C16:CoA ( Yang et al, 2020 ). In A. pernyi , E6 desaturase catalyzes C16:CoA to E6-C16:CoA ( Wang et al, 2010a ).…”

“…The sex pheromone component of Amyelois transitella , Z11, Z13-C16:Ald, is probably produced from Z11, Z13-C16:OH in the PG by oxidation ( Wang et al, 2010b ). In some moth species of Choristoneura fumiferana ( Roscoe et al, 2016 ), S. litura ( Lin et al, 2018 ), and S. insularis ( Yang et al, 2020 ), the acetyl transferases catalyze the conversion of fatty alcohols to acetate ester pheromones.…”

“…Type-I sex pheromones are alcohols, aldehydes, and acetates with 10–18 carbon chains, and are produced by most moth species. Type-II sex pheromones comprise odd polyunsaturated hydrocarbons (C17-C23) with two or three double bonds at positions three, six, or nine, in addition to their corresponding epoxide derivatives ( Matsumoto, 2010 ; Sun et al, 2019 ; Yang et al, 2020 ). The miscellaneous groups of sex pheromones comprise secondary alcohols with short-chain fatty acids (C7 and C9) and can be further classified as Type-0, while those with methyl-branched compounds are classified as Type-III ( Ando and Yamamoto, 2020 ).…”

Presentation_1.pdf

“…Several other desaturases that catalyze double bond generation in saturated fatty acyl have been identified. For instance, in Streltzoviella insularis, 5 desaturases (Z5 and E5) catalyze the conversion of C16:CoA to (E/Z)5-C16:CoA, and Z9 desaturases catalyze the conversion of C16:CoA to Z9-C16:CoA (Yang et al, 2020). In A. pernyi, E6 desaturase catalyzes C16:CoA to E6-C16:CoA (Wang et al, 2010a).…”