Elucidation of the sex-pheromone biosynthesis producing 5,7-dodecadienes in Dendrolimus punctatus (Lepidoptera: Lasiocampidae) reveals Delta 11- and Delta 9-desaturases with unusual catalytic properties.
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 Delta 11-subfamily, Dpu-Delta 11(1)-APSQ and Dpu-Delta 11(2)-LPAE, showed that they catalysed the formation of unsaturated fatty acyls (UFAs) that can be chain-shortened by beta-oxidation and subsequently reduced to the alcohol components. A first (Z)-11-desaturation step is performed by Dpu-Delta 11(2)-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-Delta 11(1)-APSQ desaturase had the unusual property of producing Delta 8 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-Delta 9-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-Delta 11(1)-APSQ and Dpu-Delta 9-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.
Liénard
Marjorie A
MA
Chemical Ecology and Ecotoxicology, Department of Biology, Lund University, Lund, Sweden. marjorie.lienard@ekol.lu.se
Lassance
Jean-Marc
JM
Wang
Hong-Lei
HL
Zhao
Cheng-Hua
CH
Piskur
Jure
J
Johansson
Tomas
T
Löfstedt
Christer
C
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D018076:DNA, Complementary / Q000737:chemistry; D044943:Fatty Acid Desaturases / Q000737:chemistry* / Q000302:isolation & purification / Q000502:physiology; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D019476:Insect Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000502:physiology; D007438:Introns; D008969:Molecular Sequence Data; D009036:Moths / Q000201:enzymology / Q000378:metabolism*; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D016415:Sequence Alignment; D020539:Sequence Analysis, Protein; D012724:Sex Attractants / Q000096:biosynthesis* / Q000737:chemistry; D013230:Stearoyl-CoA Desaturase / Q000737:chemistry* / Q000302:isolation & purification / Q000502:physiology; D013379:Substrate Specificity
D018076:DNA, Complementary; D019476:Insect Proteins; D012333:RNA, Messenger; D012724:Sex Attractants; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase