| 1. |
- De Facci, Monica, et al.
(författare)
-
Chemical composition of anal droplets of the eusocial gall-inducing thrips Kladothrips intermedius
- 2014
-
Ingår i: Chemoecology. - : Springer Science and Business Media LLC. - 1423-0445 .- 0937-7409. ; 24:3, s. 85-94
-
Tidskriftsartikel (refereegranskat)abstract
- The eusocial Acacia gall-inducing thrips Kladothrips intermedius (Thysanoptera: Phlaeothripinae) secretes defensive anal droplets when threatened. In addition to harmful substances, droplets of other thysanopteran species are known to contain semiochemicals such as alarm pheromones and/or repellents against enemies. Both Kl. intermedius larval stages and adult castes (soldiers and dispersers) produce anal droplets. In addition, a recent study has shown that soldier droplets may contain an alarm pheromone. Using multiple sampling methods (extraction in solvent, solid phase microextraction and direct injection), we analyzed the content of adults and second instar larvae anal droplets by gas chromatography coupled to mass spectrometry. Anal droplets comprised of a set of saturated and monounsaturated short-chain fatty acids, including three compounds with a terminal double bond (7-octenoic acid, 8-nonenoic acid and 9-decenoic acid). The latter are here reported for the first time in an insect species. In addition, putative unsaturated wax esters similar to those found in the secretion of other social insects were also detected in droplets. In order to investigate the physiological activity of the acids, single sensillum recordings were performed on adult Kl. intermedius as well as on adults of its kleptoparasite, Koptothrips dyskritus, targeting olfactory receptor neurons in the antennal sensilla basiconica. While olfactory perception of the acids in these species cannot be completely excluded, our analyses indicate that sensilla basiconica are not strongly sensitive to these droplet compounds.
|
|
| 2. |
- Ding, Bao Jian, et al.
(författare)
-
Biosynthesis of the sex pheromone component (E,Z)-7,9-Dodecadienyl acetate in the European Grapevine Moth, Lobesia botrana, involving ∆11 desaturation and an elusive ∆7 desaturase
- 2021
-
Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 47:3, s. 248-264
-
Tidskriftsartikel (refereegranskat)abstract
- The European grapevine moth, Lobesia botrana, uses (E,Z)-7,9-dodecadienyl acetate as its major sex pheromone component. Through in vivo labeling experiments we demonstrated that the doubly unsaturated pheromone component is produced by ∆11 desaturation of tetradecanoic acid, followed by chain shortening of (Z)-11-tetradecenoic acid to (Z)-9-dodecenoic acid, and subsequently introduction of the second double bond by an unknown ∆7 desaturase, before final reduction and acetylation. By sequencing and analyzing the transcriptome of female pheromone glands of L. botrana, we obtained 41 candidate genes that may be involved in sex pheromone production, including the genes encoding 17 fatty acyl desaturases, 13 fatty acyl reductases, 1 fatty acid synthase, 3 acyl-CoA oxidases, 1 acetyl-CoA carboxylase, 4 fatty acid transport proteins and 2 acyl-CoA binding proteins. A functional assay of desaturase and acyl-CoA oxidase gene candidates in yeast and insect cell (Sf9) heterologous expression systems revealed that Lbo_PPTQ encodes a ∆11 desaturase producing (Z)-11-tetradecenoic acid from tetradecanoic acid. Further, Lbo_31670 and Lbo_49602 encode two acyl-CoA oxidases that may produce (Z)-9-dodecenoic acid by chain shortening (Z)-11-tetradecenoic acid. The gene encoding the enzyme introducing the E7 double bond into (Z)-9-dodecenoic acid remains elusive even though we assayed 17 candidate desaturases in the two heterologous systems.
|
|
| 3. |
- Xia, Yi Han, et al.
(författare)
-
Multi-Functional Desaturases in Two Spodoptera Moths with ∆11 and ∆12 Desaturation Activities
- 2019
-
Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 0098-0331 .- 1573-1561. ; 45:4, s. 378-387
-
Tidskriftsartikel (refereegranskat)abstract
- The beet armyworm, Spodoptera exigua, uses (Z,E)-9,12-tetradecadienyl acetate as the major component of its sex pheromone. Previous isotope-labeling experiments demonstrated an unusual ∆12 desaturase activity involved in the biosynthesis of this compound; however, the putative ∆12 desaturase gene has not been reported to date. In the present study, we confirmed this ∆12 desaturation pathway by in vivo labeling experiments, and characterized candidate desaturase genes in a yeast heterologous expression system. We demonstrated that a pheromone gland-specific desaturase, SexiDes5, uses palmitic acid and the subsequently chain-shortened product (Z)-9-tetradecenoic acid as substrates to produce (Z)-11-hexadecenoic and (Z,E)-9,12-tetradecadienoic acids, respectively. In addition, the homologous desaturase SlitDes5 from the congeneric Spodoptera litura had analogous functions.
|
|
| 4. |
- Xia, Yihan, 1990, et al.
(författare)
-
Release of moth pheromone compounds from Nicotiana benthamiana upon transient expression of heterologous biosynthetic genes
- 2022
-
Ingår i: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 20:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Using genetically modified plants as natural dispensers of insect pheromones may eventually become part of a novel strategy for integrated pest management. Results: 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∆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. Conclusions: Our results pave the way for stable transformation of plants to be used as biological pheromone sources in different pest control strategies.
|
|
| 5. |
- Ding, Bao-Jian, et al.
(författare)
-
Terminal fatty-acyl-CoA desaturase involved in sex pheromone biosynthesis in the Winter Moth (Operophtera brumata)
- 2011
-
Ingår i: Insect Biochemistry and Molecular Biology. - : Elsevier BV. - 1879-0240 .- 0965-1748. ; 41, s. 715-722
-
Tidskriftsartikel (refereegranskat)abstract
- The Winter Moth (Operophtera brumata L., Lepidoptera: Geometridae) utilizes a single hydrocarbon, 1,Z3,Z6,Z9-nonadecatetraene, as its sex pheromone. We tested the hypothesis that a fatty acid precursor, Z11,Z14,Z17,19-nonadecanoic acid, is biosynthesized from α-linolenic acid, through chain elongation by one 2-carbon unit, and subsequent methyl-terminus desaturation. Our results show that labeled α-linolenic acid is indeed incorporated into the pheromone component in vivo. A fatty-acyl-CoA desaturase gene that we found to be expressed in the abdominal epidermal tissue, the presumed site of biosynthesis for type II pheromones, was characterized and expressed heterologously in a yeast system. The transgenic yeast expressing this insect derived gene could convert Z11,Z14,Z17-eicosatrienoic acid into Z11,Z14,Z17,19-eicosatetraenoic acid. These results provide evidence that a terminal desaturation step is involved in the winter moth pheromone biosynthesis, prior to the decarboxylation.
|
|
| 6. |
- Svensson, Glenn, et al.
(författare)
-
Assessment of genetic and pheromonal diversity of the Cydia strobilella species complex (Lepidoptera: Tortricidae)
- 2013
-
Ingår i: Systematic Entomology. - : Wiley. - 1365-3113 .- 0307-6970. ; 38:2, s. 305-315
-
Tidskriftsartikel (refereegranskat)abstract
- Combining pheromone trapping and genetic analyses can be useful whentrying to resolve complexes of closely related insect taxa that are difficult to distinguishbased on morphological characters. Nearctic and Palearctic populations of the spruceseed moth, Cydia strobilella L., have been considered taxonomically synonymoussince 1983, but more recent work revealing distinct sex pheromones for Canadianand Swedish moths suggest that populations in the two regions belong to differentspecies. In order to test this hypothesis, we performed field trapping using differentpheromone lures at ten sites in North America, Europe and Asia, and reconstructedphylogenetic relationships among trapped moths using mitochondrial (cytochromeoxidase subunit I ) and nuclear (elongation factor 1 alpha) DNA sequence data.Trapping data and tree topologies for both genes revealed distinct pherotypes in NorthAmerica and Eurasia. A genetically distinct population from China was investigatedfurther with respect to its sex pheromone. Electrophysiological data indicated thatChinese females produce a deviant ratio of the sex pheromone components (dienicacetates) compared to Swedish females. However, trapping experiments in both areasrevealed a similar broad response profile in males to a wide range of acetate ratios,and these populations should be considered taxonomically synonymous. A previoussuggestion of an agonistic effect on the attraction of C. strobilella males in Swedenwhen adding the corresponding alcohols to the binary acetate blend was also testedin Sweden as well as in China, with no observed effect on attraction of males. In conclusion, our study demonstrates the great potential of using pheromone trappingas a tool for identification and delimitation of taxa within cryptic species complexes.Based on our data, Nearctic and Palearctic populations of C. strobilella should beconsidered different species, and C. youngana Kearfott stat. rev. is resurrected hereas valid name for North American populations, which was the case before the revisionin 1983.
|
|
| 7. |
- Wang, Hong-Lei, et al.
(författare)
-
Biosynthesis of unusual moth pheromone components involves two different pathways in the Navel Orangeworm, Amyelois transitella
- 2010
-
Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 1573-1561 .- 0098-0331. ; 36, s. 535-547
-
Tidskriftsartikel (refereegranskat)abstract
- The sex pheromone of the navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), consists of two different types of components, one type including (11Z,13Z)-11,13-hexadecadienal (11Z,13Z-16:Ald) with a terminal functional group containing oxygen, similar to the majority of moth pheromones reported, and another type including the unusual long-chain pentaenes, (3Z,6Z,9Z,12Z,15Z)-3,6,9,12,15-tricosapentaene (3Z,6Z,9Z,12Z,15Z-23:H) and (3Z,6Z,9Z,12Z,15Z)- 3,6,9,12,15-pentacosapentaene (3Z,6Z,9Z,12Z,15Z-25:H). After decapitation of females, the titer of 11Z,13Z-16:Ald in the pheromone gland decreased significantly, whereas the titer of the pentaenes remained unchanged. Injection of a pheromone biosynthesis activating peptide (PBAN) into the abdomens of decapitated females restored the titer of 11Z,13Z-16:Ald and even increased it above that in intact females, whereas the titer of the pentaenes in the pheromone gland was not affected by PBAN injection. In addition to common fatty acids, two likely precursors of 11Z,13Z-16:Ald, i.e., (Z)-11-hexadecenoic and (11Z,13Z)-11,13-hexadecadienoic acid, as well as traces of (Z)-6-hexadecenoic acid, were found in gland extracts. In addition, pheromone gland lipids contained (5Z,8Z,11Z,14Z,17Z)-5,8,11,14,17-icosapentaenoic acid, which also was found in extracts of the rest of the abdomen. Deuterium-labeled fatty acids, (16,16,16-D(3))-hexadecanoic acid and (Z)-[13,13,14,14,15,15,16,16,16-D(9)]-11-hexadecenoic acid, were incorporated into 11Z,13Z-16:Ald after topical application to the sex pheromone gland coupled with abdominal injection of PBAN. Deuterium label was incorporated into the C(23) and C(25) pentaenes after injection of (9Z,12Z,15Z)- [17,17,18,18,18-D(5)]-9,12,15-octadecatrienoic acid into 1-2 d old female pupae. These labeling results, in conjunction with the composition of fatty acid intermediates found in pheromone gland extracts, support different pathways leading to the two pheromone components. 11Z,13Z-16:Ald is probably produced in the pheromone gland by Delta11 desaturation of palmitic acid to 11Z-16:Acid followed by a second desaturation to form 11Z,13Z-16:Acid and subsequent reduction and oxidation. The production of 3Z,6Z,9Z,12Z,15Z-23:H and 3Z,6Z,9Z,12Z,15Z-25:H may take place outside the pheromone gland, and appears to start from linolenic acid, which is elongated and desaturated to form (5Z,8Z,11Z,14Z,17Z)-5,8,11,14,17-icosapentaenoic acid, followed by two or three further elongation steps and finally reductive decarboxylation.
|
|
| 8. |
- Wang, Hong-Lei, et al.
(författare)
-
Identification of the sex pheromone of the spruce seed moth, Cydia strobilella L.
- 2010
-
Ingår i: Journal of Chemical Ecology. - : Springer Science and Business Media LLC. - 1573-1561 .- 0098-0331. ; 36:3, s. 305-313
-
Tidskriftsartikel (refereegranskat)abstract
- The spruce seed moth, Cydia strobilella L., is a serious pest on cones of spruce (Picea spp.) in the Holarctic region. Previous studies from different parts of its area of distribution have reported conflicting results on the composition of its sex pheromone. By gas chromatography with electroantennographic detection, coupled gas chromatography-mass spectrometry, a Y-tube olfactometer bioassay, and field trials, the sex pheromone of Swedish populations of the species was identified as (8E,10E)-dodecadienyl acetate and (8E,10Z)-dodecadienyl acetate. About 0.5 pg of each pheromone component was extracted per female. The most attractive blend of EE- and EZ-isomers was about 6:4, respectively, and 0.3 microg of the blend per rubber septum was the most attractive dosage for field trapping. Monounsaturated components previously reported as sex pheromone components/attractants for C. strobilella, (E)-8-dodecenyl acetate in Canadian populations and (Z)-8-dodecenol in Polish and Dutch populations, did not attract any C. strobilella in this study. Large numbers of C. jungiella Clerck were trapped by using (8E,10Z)-dodecadienyl acetate alone, whereas (Z)-8-dodecenol attracted Pammene splendidulana Guenée and P. rhediella Clerck.
|
|
| 9. |
- Wang, Hong-Lei, et al.
(författare)
-
Neofunctionalization in an ancestral insect desaturase lineage led to rare Delta(6) pheromone signals in the Chinese tussah silkworm
- 2010
-
Ingår i: Insect Biochemistry and Molecular Biology. - : Elsevier BV. - 1879-0240 .- 0965-1748. ; 40, s. 742-751
-
Tidskriftsartikel (refereegranskat)abstract
- The Chinese tussah silkworm, Antheraea pernyi (Lepidoptera: Saturniidae) produces a rare dienoic sex pheromone composed of (E,Z)-6,11-hexadecadienal, (E,Z)-6,11-hexadecadienyl acetate and (E,Z)-4,9-tetradecadienyl acetate, and for which the biosynthetic routes are yet unresolved. By means of gland composition analyses and in vivo labeling we evidenced that pheromone biosynthesis towards the immediate dienoic gland precursor, the (E,Z)-6,11-hexadecadienoic acid, involves desaturation steps with Delta(6) and Delta(11) regioselectivity. cDNA cloning of pheromone gland desaturases and heterologous expression in yeast demonstrated that the 6,11-dienoic pheromone is generated from two biosynthetic routes implicating a Delta(6) and Delta(11) desaturase duo albeit with an inverted reaction order. The two desaturases first catalyze the formation of the (E)-6-hexadecenoic acid or (Z)-11-hexadecenoic acid, key mono-unsaturated biosynthetic intermediates. Subsequently, each enzyme is able to produce the (E,Z)-6,11-hexadecadienoic acid by accommodating its non-respective mono-unsaturated product. Besides elucidating an unusually flexible pheromone biosynthetic pathway, our data provide the first identification of a biosynthetic Delta(6) desaturase involved in insect mate communication. The occurrence of this novel Delta(6) desaturase function is consistent with an evolutionary scenario involving neo-functionalization of an ancestral desaturase belonging to a gene lineage different from the Delta11-desaturases commonly involved in moth pheromone biosynthesis.
|
|
| 10. |
- Isaksson, Caroline, et al.
(författare)
-
Species-Dependent Effects of the Urban Environment on Fatty Acid Composition and Oxidative Stress in Birds
- 2017
-
Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Ecological impacts of urbanization include the loss of biodiversity and changes in species composition and population densities. However, how the urban environment affects fundamental physiological parameters is largely unknown. Here, we investigated physiological components related to health and nutrition, namely, plasma fatty acids (FA) and lipid peroxidation at inter-habitat and interspecific levels. Specifically, we compared four passerine bird species—the great tit (Parus major), the blue tit (Cyanistes caeruleus), the house sparrow (Passer domesticus), and the tree sparrow (P. montanus)—from urban and rural environments. Significant interactions between species and habitat were revealed for the majority of the FAs. Interestingly, the observed inter-habitat variation in FAs was frequently in opposite directions when comparing species from the two families (tits, Paridae; sparrows, Passeridae). These patterns suggest that sparrows and tits feed on different food sources, or modulate their FA metabolism differently, across the urban-rural gradient. By using canonical discriminant analyses (CDA), we further demonstrated species-specific signals in FA composition, with misclassification of species being <1% within habitats and <7% between habitats. Finally, the urban-rural FA differences between species and families were manifested in two indices of health. Firstly, urban blue tits had a higher total ω-6/ω-3 polyunsaturated FA ratio than rural conspecifics, which is believed to increase inflammatory responses. Secondly, urban sparrows of both species showed higher lipid peroxidation indices (indicating a higher susceptibility to lipid peroxidation if exposed to pro-oxidants), and consequently, a higher level of lipid peroxidation compared to their rural conspecifics. Collectively, the species- and habitat-specific differences in plasma FA composition, which are linked to nutrition and metabolism, suggest that the urban environment affect tits and sparrows primarily via two different pathways—inflammation and oxidative stress, respectively,—with potential consequences for the health of urban populations.
|
|
