Elucidation of the sex-pheromone biosynthesis producing 5,7-dodecadienes in Dendrolimus punctatus (Lepidoptera: Lasiocampidae) reveals Δ11- and Δ9-desaturases with unusual catalytic properties

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• 作者：Marjorie A. Lié ; nard ; Jean-Marc Lassance ; Hong-Lei Wang ; Cheng-Hua Zhao ; Jure Piš ; kur ; Tomas Johansson ; Christer Lö ; fstedt
• 关键词：Chemical communication ; Sex pheromone ; Conjugated diene ; Heterologous expression ; Gene family evolution ; Duplication ; Subfunctionalization
• 刊名：Insect Biochemistry and Molecular Biology
• 出版年：2010
• 出版时间：June 2010
• 年：2010
• 卷：40
• 期：6
• 页码：440-452
• 全文大小：1542 K

文摘

Sex pheromones produced by female moths of the Lasiocampidae family include conjugated 5,7-dodecadiene components with various oxygenated terminal groups. Here we describe the molecular cloning, heterologous expression and functional characterization of desaturases associated with the biosynthesis of these unusual chemicals. By homology-based PCR screening we characterized five cDNAs from the female moth pheromone gland that were related to other moth desaturases, and investigated their role in the production of the (Z)-5-dodecenol and (Z5,E7)-dodecadienol, major pheromone constituents of the pine caterpillar moth, Dendrolimus punctatus. Functional expression of two desaturase cDNAs belonging to the Δ11-subfamily, Dpu-Δ11₁-APSQ and Dpu-Δ11₂-LPAE, showed that they catalysed the formation of unsaturated fatty acyls (UFAs) that can be chain-shortened by β-oxidation and subsequently reduced to the alcohol components. A first (Z)-11-desaturation step is performed by Dpu-Δ11₂-LPAE on stearic acid that leads to (Z)-11-octadecenoic acyl, which is subsequently chain shortened to the (Z)-5-dodecenoic acyl precursor. The Dpu-Δ11₁-APSQ desaturase had the unusual property of producing Δ8 mono-UFA of various chain lengths, but not when transformed yeast were grown in presence of (Z)-9-hexadecenoic acyl, in which case the biosynthetic intermediate (Z9,E11)-hexadecadienoic UFA was produced. In addition to a typical Z9 activity, a third transcript, Dpu-Δ9-KPSE produced E9 mono-UFAs of various chain lengths. When provided with the (Z)-7-tetradecenoic acyl, it formed the (Z7,E9)-tetradecadienoic UFA, another biosynthetic intermediate that can be chain-shortened to (Z5,E7)-dodecadienoic acyl. Both Dpu-Δ11₁-APSQ and Dpu-Δ9-KPSE thus exhibited desaturase activities consistent with the biosynthesis of the dienoic precursor. The combined action of three desaturases in generating a dienoic sex-pheromone component emphasizes the diversity and complexity of chemical reactions that can be catalysed by pheromone biosynthetic fatty-acyl-CoA desaturases in moths.