Identification and Biosynthetic Studies of the Hydrocarbon Sex Pheromone in Utetheisa ornatrix

Abstract

The type II class of sex pheromones found in moths is composed of polyene hydrocarbons and their epoxides. Analysis of Utetheisa ornatrix females by gas chromatography-mass spectrometry and measurement of responses of male moths by coupled gas chromatography-electroantennogram detection confirmed the presence of large amounts of (Z,Z,Z)-1, 3,6,3,6,[9][10][11][12][13][14][15][16][17][18][19][20][21] and smaller amounts of (Z,Z,Z)-3,6,9-heneicosatriene (3,6,9-21:Hy). Both compounds were detected in pheromone glands of newly emerged adults, with low amounts found in the late pupal stage, indicating that sex pheromone biosynthesis started in the late pupal stage. In our population of females (several hundred sampled), approximately 90% produced the tetraene, 1,3,6,9-21:Hy, as the major component, while the other 10% produced only a large amount (1500-2000 ng) of 3,6,9-21:Hy, with no detectable amount of the tetraene. This result could indicate that two distinct populations are present in our original collection site in Florida. Decapitated female moths accumulated 3,6,9-21:Hy and 1,3,6,9-21:Hy compared to the same age normal females, indicating that female moths continuously produce pheromone. A pheromone biosynthesis activating neuropeptide (PBAN)-like neuropeptide did not affect sex pheromone production as indicated by injection of synthetic PBAN and decapitation of U. ornatrix female adults. When the labeled precursor, D4-9,12,15-18:acid, was injected into the early pupal stage, the most abundantly labeled hydrocarbons were 3,6,9-21:Hy and 1,3,6,9-21:Hy in the female adults. This result indicated that 3,6,9-21:Hy could be biosynthesized from linolenic acid through chain elongation and decarboxylation. To determine how 1,3,6,9-21:Hy is produced, D4-3,6,9-21:Hy was injected into pupae and monitored for incorporation of label. No label was incorporated into 1,3,6,9-21:Hy, although a large amount of triene, 3,6,9-21:Hy, was recovered in the pheromone gland. This indicates that U. ornatrix females do not use 3,6,9-21:Hy to produce 1,3,6,9-21:Hy, and the terminal double bond is introduced earlier in the biosynthetic pathway. RightsWorks produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted. Abstract The type II class of sex pheromones found in moths is composed of polyene hydrocarbons and their epoxides. Analysis of Utetheisa ornatrix females by gas chromatography-mass spectrometry and measurement of responses of male moths by coupled gas chromatography-electroantennogram detection confirmed the presence of large amounts of (Z,Z,Z)-1,3,6,9-heneicosatetraene (1,3,6,9-21:Hy) and smaller amounts of (Z,Z, Z)-3,6,9-heneicosatriene (3,6,9-21:Hy). Both compounds were detected in pheromone glands of newly emerged adults, with low amounts found in the late pupal stage, indicating that sex pheromone biosynthesis started in the late pupal stage. In our population of females (several hundred sampled), approximately ...

Terminal fatty-acyl-CoA desaturase involved in sex pheromone biosynthesis in the winter moth (Operophtera brumata)

“…Using in vivo labeling, we first demonstrated that the biosynthesis of 1,Z3,Z6,Z9-19:H is initiated from the diet-derived linolenic acid. Linolenic acid is also reported to serve as initial precursor for the biosynthesis of hydrocarbon pheromones in the pyralid wax moth Galleria mellonella (L.) (Stanley-Samuelson et al, 1987) and the arctiid moths Estigmene acrea (Drury) and Phragmatobia fuliginosa (L.) (Rule and Roelofs, 1989), as well as Utetheisa ornatrix (L.) (Choi et al, 2007). This supports that most polyunsaturated hydrocarbon pheromones in various moth families are likely to occur via chain elongation, desaturation and decarboxylation of linolenic acid Wang et al, 2010a,b).…”

Biosynthesis of Unusual Moth Pheromone Components Involves Two Different Pathways in the Navel Orangeworm, Amyelois transitella

“…In contrast, recent evidence suggests that even-numbered chains probably are produced by the same series of 2-carbon chain extension steps, then α-oxidation and loss of one carbon, followed by loss of a second carbon as CO or CO 2 by an oxidative mechanism (Goller et al 2007). In some cases, further desaturation also occurs somewhere in the pathway to produce compounds such as the tetraene hydrocarbon pheromones of the arctiid moth Utetheisa ornatrix (Linnaeus) (Choi et al 2007) and the geometrid moth Operophtera brumata (L.) (Zhao and Löfstedt, unpublished data). The newly formed polyene skeletons then are transported through the hemolymph by lipophorin carriers from the oenocytes to the pheromone gland (Wei et al 2004; Matsuoka et al 2006).…”

“…According to studies published to date, pheromone biosynthesis activating neuropeptides (PBANs) are not involved in the production of unsaturated hydrocarbon pheromone components in the arctiid moth U. ornatrix (Choi et al 2007) or the geometrid moth Ascotis selenaria cretacea (Butler) (Wei et al 2004), but they are involved in the epoxidation of these hydrocarbons in the pheromone gland, for those species that use epoxide pheromones alone or in combination with unsaturated hydrocarbons (e.g., the lymantriid moth Lymantria dispar L. (Jurenka et al 2003) and the geometrid moth A. selenaria cretacea B. (Ando et al 1997; Wei et al 2004)).…”

Insect pheromones: An overview of function, form, and discovery

“…152 Other than serving as ''on'' or ''off'' switches for mating, attrac-153 tive pheromones can also function as nuptial gifts and signals that 154 convey information about the quality of the sender. For example, 155 pyrrolizidine compounds, which are toxic substances for many ani-156 mals, are used by Arctiid moths in some cases as attractants for…”

“…Several desaturases exhibit 539 specificity for monounsaturated substrates [149][150][151][152][153][154]. Lastly, sev-540 eral desaturases in Lepidoptera are known to produce triene pher-541 omone components, also using linoleic acid as a substrate [89,155]. …”