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1.
Pestic Biochem Physiol ; 165: 104542, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359552

RESUMO

The tea geometrid moth Ectropis obliqua Prout is one of the most serious moth pests in tea plants, and its sex pheromones have been identified as typical Type-II polyunsaturated hydrocarbons and epoxide derivatives. Therefore, the E. obliqua male olfactory system provides a good model to study the molecular basis of Type-II sex pheromone recognition as well as functional gene evolution towards structurally different types of moth sex pheromones. In this study, we identified the full-length sequence of a pheromone-binding protein, EoblPBP2 and revealed that it clustered together with the lepidopteran PBP2 subfamily, which binds Type I acetate pheromones. These findings suggest that the EoblPBP2 sequence and physiological function are conserved, although E. obliqua evolved Type II hydrocarbon and epoxide sex pheromones structurally different from Type I acetates. To examine this hypothesis, we studied the expression patterns and in vitro functions of EoblPBP2 in detail. Quantitative real-time PCR experiments showed that EoblPBP2 was predominantly expressed in male E. obliqua antennae. Fluorescence in situ hybridization further demonstrated that the EoblPBP2 gene was abundantly expressed in the pheromone-sensitive sensilla trichodea Str-I in male E. obliqua. The physiological function of recombinant EoblPBP2 was then examined using a competitive binding assay. The results showed that EoblPBP2 had high affinities for three E. obliqua Type II sex pheromone components and Type I acetate pheromones in comparison to some plant volatiles. These results indicate that PBP2 is involved in the detection of Type II pheromones in E. obliqua and it still retains high binding affinities to acetate pheromones and some green leaf ester volatiles.


Assuntos
Mariposas , Atrativos Sexuais , Animais , Proteínas de Transporte , Hibridização in Situ Fluorescente , Proteínas de Insetos , Masculino , Feromônios , Chá
2.
Pestic Biochem Physiol ; 164: 173-182, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284124

RESUMO

Athetis lepigone (Alep) is a polyphagous pest native to Europe and Asia that has experienced major outbreaks in the summer maize area of China since 2011 and has shown evidence of resistance to some insecticides. Insect olfaction is crucial for recognition of sex pheromones, host plant volatiles and even insecticides, in which two general-odorant binding proteins (GOBPs) play important roles. To elucidate the functions of GOBPs in A. lepigone, we first expressed the two AlepGOBP proteins in the E. coli expression system. Then, the results of fluorescence competitive binding assays demonstrated that the high binding affinity of AlepGOBP2 with sex pheromones [(Z)-7-dodecenyl acetate (Z7-12:Ac), Ki = 0.65 µM; (Z)-9-tetradecenyl acetate (Z9-14:Ac), Ki = 0.83 µM], two maize plant volatiles [Ocimene, Ki = 9.63 µM; (E)-ß-Farnesene, Ki = 4.76 µM] and two insecticides (Chlorpyrifos Ki =5.61 µM; Phoxim, Ki = 4.38 µM). However, AlepGOBP1 could only bind Ocimene (Ki = 13.0 µM) and two insecticides (Chlorpyrifos Ki =4.46 µM; Phoxim, Ki = 3.27 µM). These results clearly suggest that AlepGOBP1 and AlepGOBP2 differentiate among odorants and other ligands. The molecular docking results further revealed different key residues involved in the ligand binding of AlepGOBPs. In summary, this study provides a foundation for exploring the olfactory mechanism of A. lepigone and identified two potential target genes for the development of highly effective insecticides in the future.


Assuntos
Inseticidas , Mariposas , Atrativos Sexuais , Animais , China , Escherichia coli , Proteínas de Insetos , Simulação de Acoplamento Molecular , Odorantes , Feromônios
3.
PLoS One ; 15(4): e0231689, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298345

RESUMO

The giant sugarcane borer Telchin licus (Drury, 1773) (Lepidoptera: Castniidae) is a day-flying moth pest of sugarcane, pineapples and bananas. To better understand the chemical communication in this species, we examined the morphology of its olfactory system and the chemical composition of its body parts. The ventral surface of the clubbed antennae of T. licus has six morphological types of sensilla: sensilla trichodea, basiconica, chaetica, squamiforma, coeloconica, and auricillica. The telescopic ovipositor shows no evidence of a sexual gland, or female-specific compounds. On the other hand, the midleg basitarsus of males releases (E,Z)-2,13-octadecadienol and (Z,E)-2,13-octadecadienol, which are electroantennographically active in both sexes. These compounds are known female sex pheromones in the Sesiidae family and are male-specific compounds in another castniid moth, although further investigations are necessary to elucidate their ecological role in the Castniidae family.


Assuntos
Mariposas/anatomia & histologia , Mariposas/fisiologia , Animais , Antenas de Artrópodes/anatomia & histologia , Antenas de Artrópodes/química , Antenas de Artrópodes/fisiologia , Antenas de Artrópodes/ultraestrutura , Feminino , Masculino , Mariposas/química , Mariposas/ultraestrutura , Oviposição , Saccharum/parasitologia , Atrativos Sexuais/análise , Atrativos Sexuais/metabolismo
4.
J Chem Ecol ; 46(2): 115-127, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056064

RESUMO

Whittleia retiella (Newman, 1847) is a threatened salt marsh species of the bagworm moth family Psychidae. For its preservation it is necessary to develop efficient tools to survey its distribution and habitat requirements in order to use appropriate conservation methods. Such tools may be pheromone-based monitoring systems, which have documented efficacy in establishing the occurrence of cryptic insect species in nature. By using gas chromatography combined with electroantennographic detection (GC-EAD), we found two compounds in female W. retiella headspace samples and whole-body extracts that elicited electrophysiological activity in male antennae. Gas chromatograpy coupled with mass spectrometry (GC-MS) operating in electron impact (EI) mode and comparison of the analytical data with those of synthetic reference compounds showed the chemical structures of these putative pheromone components to be (1S)-1-methylpropyl (5Z)-dec-5-enoate and 1-methylethyl (5Z)-dec-5-enoate. Field assays using baits loaded with synthetic compounds revealed that conspecific males were attracted to (1S)-1-methylpropyl (5Z)-dec-5-enoate alone or in combination with 1-methylethyl (5Z)-dec-5-enoate, whereas 1-methylethyl (5Z)-dec-5-enoate neither attracted nor repelled males in the field assays when tested alone. This study shows the potential of using (1S)-1-methylpropyl (5Z)-dec-5-enoate for monitoring W. retiella to gather more detailed information about the geographic distribution and habitat needs of this rare moth.


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/química , Animais , Comportamento Animal/efeitos dos fármacos , Fenômenos Eletrofisiológicos , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Atrativos Sexuais/análise , Atrativos Sexuais/farmacologia , Estereoisomerismo , Áreas Alagadas
5.
Nat Commun ; 11(1): 53, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896746

RESUMO

While the diversity of sex pheromone communication systems across insects is well documented, the mechanisms that lead to such diversity are not well understood. Sex pheromones constitute a species-specific system of sexual communication that reinforces interspecific reproductive isolation. When odor blends evolve, the efficacy of male-female communication becomes compromised, unless preference for novel blends also evolves. We explore odor learning as a possible mechanism leading to changes in sex pheromone preferences in the butterfly Bicyclus anynana. Our experiments reveal mating patterns suggesting that mating bias for new blends can develop following a short learning experience, and that this maternal experience impacts the mating outcome of offspring without further exposure. We propose that odor learning can be a key factor in the evolution of sex pheromone blend recognition and in chemosensory speciation.


Assuntos
Borboletas/efeitos dos fármacos , Borboletas/fisiologia , Preferência de Acasalamento Animal/efeitos dos fármacos , Atrativos Sexuais/farmacologia , Álcoois/farmacologia , Aldeídos/farmacologia , Animais , Álcoois Graxos/farmacologia , Feminino , Masculino , Preferência de Acasalamento Animal/fisiologia , Atrativos Sexuais/química , Atrativos Sexuais/fisiologia , Terpenos/farmacologia , Asas de Animais
6.
PLoS One ; 15(1): e0227666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31945099

RESUMO

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, ß-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.


Assuntos
Genes de Insetos , Mariposas/genética , Mariposas/metabolismo , Atrativos Sexuais/biossíntese , Atrativos Sexuais/genética , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Animais , Vias Biossintéticas/genética , China , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Filogenia , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Glândulas Odoríferas/metabolismo , Análise de Sequência de RNA , Transcriptoma
7.
J Chem Ecol ; 46(2): 128-137, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31907752

RESUMO

Cuticular compounds (CCs) that cover the surface of insects primarily serve as protection against entomopathogens, harmful substances, and desiccation. However, CCs may also have secondary signaling functions. By studying the role of CCs in intraspecific interactions, we may advance our understanding of the evolution of pheromonal communication in insects. We previously found that the gregarious parasitoid, Cotesia glomerata (L.), uses heptanal as a repellent pheromone to help avoid mate competition among sibling males, whereas another cuticular aldehyde, nonanal, is part of the female-produced attractive sex pheromone. Here, we show that the same aldehydes have different pheromonal functions in a related solitary parasitoid, Cotesia marginiventris (Cresson). Heptanal enhances the attractiveness of the female's sex pheromone, whereas nonanal does not affect a female's attractiveness. Hence, these common aldehydes are differentially used by the two Cotesia species to mediate, synergistically, the attractiveness of the main constituents of their respective sex pheromones. The specificity of the complete sex pheromone blend is apparently regulated by two specific, less volatile compounds, which evoke strong electroantennographic (EAG) responses. This is the first demonstration that volatile CCs have evolved distinct pheromonal functions to aid divergent mating strategies in closely related species. We discuss the possibility that additional compounds are involved in attraction and that, like the aldehydes, they are likely oxidative products of unsaturated cuticular hydrocarbons.


Assuntos
Aldeídos/química , Himenópteros/fisiologia , Atrativos Sexuais/química , Aldeídos/análise , Aldeídos/farmacologia , Animais , Sinais (Psicologia) , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Atrativos Sexuais/análise , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
8.
Pestic Biochem Physiol ; 163: 227-234, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31973861

RESUMO

Odorant-degrading enzymes (ODEs) are considered to play key roles in odorant inactivation to maintain the odorant receptor sensitivity of insects. Some members of carboxylesterase (CXE) is a major sub-family of ODEs. However, only a few CXEs have been functionally characterized so far. In the present study, we cloned the antennal esterase SexiCXE11 cDNA full-length sequences from the male antennae of a notorious crop pest, Spodoptera exigua, and its encoded 538 amino acids. It was similar to other insect esterases and had the characteristics of a carboxylesterase. We expressed recombinant enzyme in High-Five insect cells and obtained the high level purified recombinant protein by affinity column. Furthermore we test enzyme activity toward its two acetate sex pheromone components (Z9,E12-Tetradecadienyl acetate, Z9E12-14:Ac and Z9-Tetradecenyl acetate, Z9-14:Ac) and other 18 ester plant volatiles. Our results demonstrated that SexiCXE11 degraded acetate sex pheromone components with similar degradation activities (about 15.75% with Z9E12-14:Ac and 19.28% with Z9-14:Ac) and plant volatiles with a relatively high activity such as pentyl acetate and (Z)-3-hexenyl caproate. SexiCXE11 had high hydrolytic activity with these two ester odorants (>50% degradation), which is characterized that although a ubiquitous expression esterase SexiCXE11 may be partly involved with olfaction. This study may facilitate a better understanding of moth ODE differentiation and suggest strategies for the development of new pest behavior inhibitors.


Assuntos
Atrativos Sexuais , Animais , Carboxilesterase , Ésteres , Proteínas de Insetos , Masculino , Feromônios , Plantas , Spodoptera
9.
J Chem Ecol ; 46(1): 1-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31840210

RESUMO

The rice stalk stink bug, Tibraca limbativentris, is an important rice pest in Brazil with a high invasive potential for Mexico and the USA. The sex pheromone of this species was previously identified as a combination of two stereoisomers of 1,10-bisaboladien-3-ol (zingiberenol), but the absolute configurations of these sesquiterpenes were not determined, neither were their effect(s) on T. limbativentris behavior evaluated. In this study, using two chiral columns, we compared retention times of the two natural 1,10-bisaboladien-3-ol stereoisomers from air-entrainment samples of male T. limbativentris with those of synthetic stereoisomers of 1,10-bisaboladien-3-ol. The results showed that T. limbativentris males produce (3S,6S,7R)-1,10-bisaboladien-3-ol (1) and (3R,6S,7R)-1,10-bisaboladien-3-ol (5) as their sex pheromone. Two new minor, male-specific components were also identified as cis and trans isomers of 2,10-bisaboladien-1-ol (sesquipiperitol). Y-tube olfactometer bioassays showed that the major (3S,6S,7R) isomer 1 was essential for attraction of T. limbativentris females, but the minor (3R,6S,7R) isomer 2 was not, nor did it show synergistic/antagonistic effects when added to the major isomer. The (1S,6S,7R) and (1R,6S,7R) stereoisomers of sesquipepiritol also attracted T. limbativentris females.


Assuntos
Comportamento Animal/efeitos dos fármacos , Heterópteros/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Atrativos Sexuais/química , Atrativos Sexuais/farmacologia , Animais , Cromatografia Gasosa , Feminino , Heterópteros/metabolismo , Masculino , Estereoisomerismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química
10.
Bull Entomol Res ; 110(1): 96-105, 2020 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-31190656

RESUMO

Diamides have been used worldwide to manage the diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), however some strains showed resistance to these molecules. Also, pheromone traps could be used to manage this pest, hence reducing the use of insecticides in the field. Resistant DBM strains may have biological disadvantages in comparison to susceptible strains in areas without sprays, including reduction in fitness or behavioral changes. Therefore, the aim of this study was to investigate whether DBM strains resistant to chlorantraniliprole showed adaptive costs that could alter male attraction to the sex pheromone, in comparison to susceptible strains in the laboratory and semi-field conditions. First, the LC1, LC10, LC25, and LC50 of DBM to chlorantraniliprole were established, which were 0.003, 0.005, 0.007, and 0.011 mg a.i. liter-1, and 5.88, 24.80, 57.22, and 144.87 mg a.i. liter-1 for the susceptible and resistant strains, respectively. Development and reproduction of DBM strains subjected to those concentrations were compared. Later, male response to the sex pheromone was investigated in a Y-tube in the laboratory and in a greenhouse to pheromone traps. Resistant DBM strain showed an adaptive cost in comparison to the susceptible strain that can result in a delay in population growth in the field when selection pressure is absent. Conversely, resistant males have no olfactory response alteration in comparison to susceptible males, consistently at 3 (P = 0.6848) and 7 days (P = 0.9140) after release, suggesting that pheromone traps continue to be a viable alternative to manage DBM in an IPM system.


Assuntos
Adaptação Biológica , Inseticidas , Mariposas/fisiologia , Comportamento Sexual Animal/fisiologia , ortoaminobenzoatos , Animais , Resistência a Inseticidas/fisiologia , Masculino , Atrativos Sexuais , Olfato
11.
Insect Biochem Mol Biol ; 116: 103260, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682920

RESUMO

Most moths utilize sex pheromones released by the female to attract a mate. Females produce the sex pheromone in the pheromone gland in a biosynthetic pathway which consists of several key enzymes. Fatty acyl-CoA reductase is one of the key enzymes, which catalyzes the conversion of fatty acyl-CoA to the corresponding alcohol, playing an important role in producing the final proportion of each pheromone component. In Helicoverpa zea, (Z)-11-hexadecenal is the major sex pheromone component in female pheromone glands and previously a large amount of hexadecanal was also found in female and male tarsi. In our previous study, we compared the transcriptome between pheromone glands and tarsi and found 20 fatty acyl-CoA reductases in both tissues. In this study, we functionally characterized four FARs which were expressed at high levels according to the transcriptome of pheromone glands and tarsi. Fatty acyl-CoA reductase 1 was homologous to other moth pheromone gland specific fatty acyl-CoA reductases, and it was also present in male tarsi. Functional expression in yeast cells indicates that only fatty acyl-CoA reductase 1 was able to produce fatty alcohols. In addition, a decreased mRNA level of fatty acyl-CoA reductase 1 in female pheromone glands and male tarsi by RNAi knockdown caused a significant decrease in the production of (Z)-11-hexadecenal in pheromone glands and hexadecanal in male tarsi. This study is the first to demonstrate the direct function of a fatty acyl-CoA reductase in male tarsi and also confirms its role in sex pheromone biosynthesis in H. zea.


Assuntos
Aldeído Oxirredutases/genética , Proteínas de Insetos/genética , Mariposas/metabolismo , Aldeído Oxirredutases/química , Aldeído Oxirredutases/metabolismo , Aldeídos/metabolismo , Sequência de Aminoácidos , Animais , Tornozelo , Glândulas Exócrinas/química , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Mariposas/crescimento & desenvolvimento , Filogenia , Alinhamento de Sequência , Atrativos Sexuais/biossíntese , Transcriptoma
12.
Pest Manag Sci ; 76(4): 1435-1442, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31639267

RESUMO

BACKGROUND: The cashew stem borer Anthistarcha binocularis (Meyrick) is a major pest in cashew orchards in Brazil. The damage caused by the larvae results in economic losses, and the available chemical control is not suitable because of the endophytic nature of A. binocularis. The identification of the A. binocularis sex pheromone could provide novel applications for the detection and monitoring of this species. RESULTS: Two compounds from female sex gland extracts elicited electrophysiological responses on male antennae. They were identified as dodec-6-en-1-ol and dodec-6-en-1-yl acetate by gas chromatography-mass spectrometry. E/Z stereoisomers of both compounds were synthesized, and the electroantennograms for the synthetic compounds showed the strongest responses for the (E)-stereoisomers of the alcohol and acetate. In a field trial, the E6-12:OH/E6-12:OAc mixture attracted male A. binocularis, whereas the Z6-12:OH/Z6-12:OAc mixture attracted no specimens. CONCLUSIONS: The bioactive compounds from the sex pheromone of A. binocularis have been identified as a mixture of two previously unidentified pheromone compounds: E6-12:OH and E6-12:OAc. The mixture of both compounds was attractive to males in preliminary field experiments, and this study is the first report of Δ6-unsaturated monoenyl pheromone compounds in Lepidoptera. © 2019 Society of Chemical Industry.


Assuntos
Anacardium , Lepidópteros , Animais , Brasil , Feminino , Masculino , Feromônios , Atrativos Sexuais
13.
Biosci Biotechnol Biochem ; 84(1): 25-30, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31516064

RESUMO

The Japanese orange fly, Bactrocera tsuneonis, infests various citrus crops. While male pheromone components accumulated in the rectal glands are well characterized for Bactrocera, but information regarding the chemical factors involved in the life cycles of B. tsuneonis remains scarce. Herein, several volatile chemicals including a γ-decalactone, (3R,4R)-3-hydroxy-4-decanolide [(3R,4R)-HD], were identified as major components, along with acetamide and spiroketals as minor components in the rectal gland complexes of male B. tsuneonis flies. The lactone (3R,4R)-HD was also identified in female rectal gland complexes. The amount of this compound in mature males was significantly higher than those observed in females and immature males. The lactone (3R,4R)-HD was detected in flies fed with sucrose only, indicating that this lactone is not derived from dietary sources during adulthood, but biosynthesized in vivo. The predominant accumulation of (3R,4R)-HD in mature males also suggests a possible role in reproductive behavior.


Assuntos
Lactonas/química , Glândula de Sal/química , Tephritidae/fisiologia , Acetamidas/síntese química , Acetamidas/química , Animais , Cromatografia Gasosa , Citrus , Dieta , Feminino , Furanos/síntese química , Furanos/química , Japão , Lactonas/síntese química , Masculino , Espectrometria de Massas , Reprodução/fisiologia , Atrativos Sexuais/química , Comportamento Sexual Animal/fisiologia , Compostos de Espiro/síntese química , Compostos de Espiro/química , Sacarose
14.
J Chem Ecol ; 46(1): 10-20, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31845137

RESUMO

Female moths release sex pheromone to attract mates. In most species, sex pheromone is produced in, and released from, a specific gland. In a previous study, we used empirical data and compartmental modeling to account for the major pheromone gland processes of female Chloridea virescens: synthesis, storage, catabolism and release; we found that females released little (20-30%) of their pheromone, with most catabolized. The recent publication of a new pheromone collection method led us to reinvestigate pheromone release and catabolism in C. virescens on the basis that our original study might have underestimated release rate (thereby overestimating catabolism) due to methodology and females not calling (releasing) continuously. Further we wished to compare pheromone storage/catabolism between calling and non-calling females. First, we observed calling intermittency of females. Then, using decapitated females, we used the new collection method, along with compartmental modeling, gland sampling and stable isotope labeling, to determine differences in pheromone release, catabolism and storage between (forced) simulated calling and non-calling females. We found, (i) intact 1 d females call intermittently; (ii) pheromone is released at a higher rate than previously determined, with simulations estimating that continuously calling females release ca. 70% of their pheromone (only 30% catabolized); (iii) extension (calling)/retraction of the ovipositor is a highly effective "on/off' mechanism for release; (iv) both calling and non-calling females store most pheromone on or near the gland surface, but calling females catabolize less pheromone; (v) females are capable of producing and releasing pheromone very rapidly. Thus, not only is the moth pheromone gland efficient, in terms of the proportion of pheromone released Vs. catabolized, but it is highly effective at shutting on/off a high flux of pheromone for release.


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/metabolismo , Comportamento Sexual Animal , Aldeídos/análise , Aldeídos/farmacologia , Animais , Isótopos de Carbono/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glucose/química , Glucose/metabolismo , Marcação por Isótopo , Masculino , Glândulas Odoríferas/metabolismo , Atrativos Sexuais/análise , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
15.
J Chem Ecol ; 46(1): 21-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31853815

RESUMO

Female Helicoverpa armigera emit a pheromone, comprised of a 98:2 ratio of (Z)-11-hexadecenal to (Z)-9-hexadecenal, to attract males. It has been proposed that "immature" female H. armigera modulate attraction of males by emitting an antagonist, (Z)-11-hexadecenol, along with pheromone during the first two nights of calling. However, it is unclear why females would call and simultaneously release pheromone and an antagonist. We conducted observations of female calling during the first five nights after adult emergence to determine periodicity. We also measured the relative abundance of (Z)-11-hexadecenol to the major component, (Z)-11-hexadecenal, on the surface of the gland of calling females and compared it to the ratio of these two compounds inside the gland over the first three nights after adult emergence to determine how much antagonist may be released. We found that young females (< 1-d-old) are unlikely to call and, based on the relative proportion of (Z)-11-hexadecenol on the gland surface, even if they did call would be unlikely to release sufficient (Z)-11-hexadecenol to diminish male attraction.


Assuntos
Fertilidade/fisiologia , Mariposas/fisiologia , Atrativos Sexuais/química , Aldeídos/análise , Aldeídos/isolamento & purificação , Aldeídos/farmacologia , Animais , Cromatografia Gasosa , Feminino , Masculino , Atrativos Sexuais/análise , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Microextração em Fase Sólida , Estereoisomerismo
16.
J Photochem Photobiol B ; 203: 111747, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31884348

RESUMO

In the present study, a simple and a selective colorimetric method for pheromone detection to diagnose estrus in cattle was established based on the l-tyrosine functionalized silver nanoparticles (l-TyrAgNPs). The synthesized silver nanoparticles was spotted by color change (colorless to pale yellow) due to surface plasmon resonance (SPR). In order to confirm, Ag nanoparticles was characterized by field emission scanning electron microscopy (FESEM), dynamic light scattering (DLS) and zeta potential, X-ray diffraction (XRD) and UV- Vis spectrophotometer. It was found that the pre-colored Ag colloids could be turned from yellow to reddish-brown by the addition of the sex pheromones such as acetic acid or propionic acid, which may have potential application in the colorimetric sensor. The augmented optical nature of nanoparticles furnishes a suitable base to develop a colorimetric sensor for bovine sex pheromones detection. In addition, the computational analyses are critically required to validate residual interactions of bovine odorant-binding protein (OBP) with pheromones. The method was successfully applied to the detection of acetic acid or propionic acid using a biological molecule l-Tyr AgNPs. These results clearly indicate that the biosynthesis of l-Tyr AgNPs can be used as a promising colorimetric sensor for accurate time of estrus prediction in bovine.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Atrativos Sexuais/análise , Prata/química , Tirosina/química , Animais , Sítios de Ligação , Bovinos , Colorimetria , Detecção do Estro/métodos , Receptores Odorantes/química , Receptores Odorantes/metabolismo
17.
Elife ; 82019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31818368

RESUMO

Sex pheromone receptors (PRs) are key players in chemical communication between mating partners in insects. In the highly diversified insect order Lepidoptera, male PRs tuned to female-emitted type I pheromones (which make up the vast majority of pheromones identified) form a dedicated subfamily of odorant receptors (ORs). Here, using a combination of heterologous expression and in vivo genome editing methods, we bring functional evidence that at least one moth PR does not belong to this subfamily but to a distantly related OR lineage. This PR, identified in the cotton leafworm Spodoptera littoralis, is highly expressed in male antennae and is specifically tuned to the major sex pheromone component emitted by females. Together with a comprehensive phylogenetic analysis of moth ORs, our functional data suggest two independent apparitions of PRs tuned to type I pheromones in Lepidoptera, opening up a new path for studying the evolution of moth pheromone communication.


Assuntos
Proteínas de Insetos/metabolismo , Mariposas/metabolismo , Receptores de Feromonas/metabolismo , Atrativos Sexuais/metabolismo , Animais , Comportamento Animal , Sistemas CRISPR-Cas , Drosophila/genética , Drosophila/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Proteínas de Insetos/genética , Lepidópteros/genética , Lepidópteros/metabolismo , Masculino , Mariposas/genética , Receptores Odorantes , Receptores de Feromonas/classificação , Receptores de Feromonas/genética , Spodoptera/genética , Spodoptera/metabolismo , Transcriptoma , Xenopus/genética , Xenopus/metabolismo
18.
Proc Natl Acad Sci U S A ; 116(49): 24668-24675, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31748269

RESUMO

Plants respond to insect infestation with defenses targeting insect eggs on their leaves and the feeding insects. Upon perceiving cues indicating imminent herbivory, such as damage-induced leaf odors emitted by neighboring plants, they are able to prime their defenses against feeding insects. Yet it remains unknown whether plants can amplify their defenses against insect eggs by responding to cues indicating imminent egg deposition. Here, we tested the hypothesis that a plant strengthens its defenses against insect eggs by responding to insect sex pheromones. Our study shows that preexposure of Pinus sylvestris to pine sawfly sex pheromones reduces the survival rate of subsequently laid sawfly eggs. Exposure to pheromones does not significantly affect the pine needle water content, but results in increased needle hydrogen peroxide concentrations and increased expression of defense-related pine genes such as SOD (superoxide dismutase), LOX (lipoxygenase), PAL (phenylalanine ammonia lyase), and PR-1 (pathogenesis related protein 1) after egg deposition. These results support our hypothesis that plant responses to sex pheromones emitted by an herbivorous insect can boost plant defensive responses to insect egg deposition, thus highlighting the ability of a plant to mobilize its defenses very early against an initial phase of insect attack, the egg deposition.


Assuntos
Interações Hospedeiro-Parasita/imunologia , Himenópteros/patogenicidade , Óvulo/imunologia , Pinus sylvestris/imunologia , Atrativos Sexuais/imunologia , Animais , Feminino , Herbivoria/fisiologia , Peróxido de Hidrogênio/imunologia , Peróxido de Hidrogênio/metabolismo , Himenópteros/fisiologia , Masculino , Odorantes , Oviposição/imunologia , Pinus sylvestris/parasitologia , Folhas de Planta/imunologia , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Atrativos Sexuais/metabolismo
19.
PLoS One ; 14(11): e0225003, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31738776

RESUMO

Polyphenism is a type of phenotypic plasticity supposedly adaptive to drastic and recurrent changes in the environment such as seasonal alternation in temperate and tropical regions. The butterfly Bicyclus anynana shows polyphenism with well-described wet and dry seasonal forms in sub-Saharan Africa, displaying striking morphological, physiological and behavioural differences in response to higher or lower developmental temperatures. During the seasonal transition in the wild, the intermediate phenotype co-occurs with wet and dry phenotypes. In this study, we aimed to characterize the secondary sexually-selected wing traits of the intermediate form to infer its potential fitness compared to wet and dry phenotypes. Among the previously described wing morphological traits, we first showed that the area of the fifth eyespot on the ventral hindwing is the most discriminant trait to identify wet, dry and intermediate phenotypes in both sexes. Second, we characterized the intermediate form for two secondary sexually-selected wing traits: the area and UV reflectance of the dorsal forewing pupil and the composition of the male sex pheromone. We showed that values of these two traits are often between those of the wet and dry phenotypes. Third, we observed increasing male sex pheromone production in ageing dry and wet phenotypes. Our results contrast with previous reports of values for sexually-selected traits in wet and dry seasonal forms, which might be explained by differences in rearing conditions or sample size effects among studies. Wet, dry and intermediate phenotypes display redundant sexually dimorphic traits, including sexually-selected traits that can inform about their developmental temperature in sexual interactions.


Assuntos
Adaptação Fisiológica , Borboletas/anatomia & histologia , Característica Quantitativa Herdável , Atrativos Sexuais/farmacologia , Caracteres Sexuais , Vias Visuais/fisiologia , Asas de Animais/anatomia & histologia , Animais , Feminino , Malaui , Masculino , Fenótipo , Estações do Ano , Temperatura , Asas de Animais/efeitos dos fármacos
20.
PLoS Negl Trop Dis ; 13(10): e0007767, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31652261

RESUMO

OBJECTIVE: To evaluate the efficacy of a synthetic sex-aggregation pheromone of the sand fly vector Lu. longipalpis, co-located with residual insecticide, to reduce the infection incidence of Leishmania infantum in the canine reservoir. METHODS: A stratified cluster randomised trial was designed to detect a 50% reduction in canine incident infection after 24 months in 42 recruited clusters, randomly assigned to one of three intervention arms (14 cluster each): synthetic pheromone + insecticide, insecticide-impregnated dog collars, or placebo control. Infection incidence was measured by seroconversion to anti-Leishmania serum antibody, Leishmania parasite detection and canine tissue parasite loads. Changes in relative Lu. longipalpis abundance within households were measured by setting three CDC light traps per household. RESULTS: A total 1,454 seronegative dogs were followed-up for a median 15.2 (95% C.I.s: 14.6, 16.2) months per cluster. The pheromone + insecticide intervention provided 13% (95% C.I. 0%, 44.0%) protection against anti-Leishmania antibody seroconversion, 52% (95% C.I. 6.2%, 74·9%) against parasite infection, reduced tissue parasite loads by 53% (95% C.I. 5.4%, 76.7%), and reduced household female sand fly abundance by 49% (95% C.I. 8.2%, 71.3%). Variation in the efficacy against seroconversion varied between trial strata. Equivalent protection attributed to the impregnated-collars were 36% (95% C.I. 14.4%, 51.8%), 23% (95% C.I. 0%, 57·5%), 48% (95% C.I. 0%, 73.4%) and 43% (95% C.I. 0%, 67.9%), respectively. Comparison of the two interventions showed no statistically consistent differences in their efficacies; however, the errors were broad for all outcomes. Reductions in sand fly numbers were predominant where insecticide was located (chicken and dog sleeping sites), with no evidence of insecticide-induced repellence onto humans or dogs. CONCLUSION: The synthetic pheromone co-located with insecticide provides protection particularly against canine L. infantum parasite transmission and sand fly vector abundance. The effect estimates are not dissimilar to those of the insecticide-impregnated collars, which are documented to reduce canine infection incidence, human infection and clinical VL disease incidence, in different global regions. The trialled novel lure-and-kill approach is a low-cost potential vector control tool against ZVL in the Americas.


Assuntos
Doenças do Cão/prevenção & controle , Inseticidas/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/prevenção & controle , Psychodidae/metabolismo , Atrativos Sexuais/metabolismo , Atrativos Sexuais/farmacologia , Animais , Brasil , Controle de Doenças Transmissíveis/métodos , Reservatórios de Doenças , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Feminino , Humanos , Incidência , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Leishmaniose Visceral/veterinária , Masculino , Carga Parasitária , Controle de Pragas/métodos , Inquéritos e Questionários
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