| 1. |
- Baker, T. C., et al.
(author)
-
Identification and bioassay of sex pheromone components of carob moth, Ectomyelois ceratoniae (Zeller)
- 1991
-
In: Journal of Chemical Ecology. - 0098-0331. ; 17:10, s. 1973-1988
-
Journal article (peer-reviewed)abstract
- Three sex pheromone components of the carob moth were isolated and identified from the extract of female pheromone glands, using a variety of techniques including coupled gas chromatographic-electroantennographic recordings, coupled gas chromatographic-mass spectrometric analysis, microozonolysis, electroantennographic assays of monounsaturated standards, wind-tunnel bioassays, and field trials. The major component was identified as (Z,E)-9,11,13-tetradecatrienal, a novel lepidopterous pheromone component structure. Two minor components, either one of which improves the upwind flight response of males when blended with the major component, were identified as (Z,E)-9,11-tetradecadienal, and (Z)-9-tetra-decenal.
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| 2. |
- Baker, T. C., et al.
(author)
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Isolation, identification and synthesis of sex pheromone components of the carob moth, Ectomyelois ceratoniae
- 1989
-
In: Tetrahedron Letters. - 0040-4039. ; 30:22, s. 2901-2902
-
Journal article (peer-reviewed)abstract
- The sex pheromone of females of the carob moth, Ectomyelois ceratoniae, was identified to be a mixture of (Z,E)-9,11,13-tetradecatrienal, (Z,E)-9,11-tetradecadienal and (Z)-9-tetradecenal in the ratio of 10:1:1. A synthetic blend proved to be attractive. GC/EAD + GC/MS investigations showed (Z,E)-9,11,13-tetradecatrienal, (Z,E)-9,11-tetradecadienal and (Z)-9-tetradecenal to be the sex pheromone of the carob moth. Blends of synthetic compounds are active.
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| 3. |
- Takanashi, T, et al.
(author)
-
Unusual response characteristics of pheromone-specific olfactory receptor neurons in the Asian corn borer moth, Ostrinia furnacalis
- 2006
-
In: Journal of Experimental Biology. - : The Company of Biologists. - 1477-9145 .- 0022-0949. ; 209:24, s. 4946-4956
-
Journal article (peer-reviewed)abstract
- Male moth pheromone-detecting receptor neurons are known to be highly specific and very sensitive. We investigated physiological and behavioral responses to female sex pheromone components in male Ostrinia furnacalis moths (Lepidoptera: Crambidae). Using recordings from a cut-sensillum technique, trichoid sensilla could be grouped into four physiological types (1-4), according to the response of receptor neurons to the two major pheromone components, (E)-12- and (Z)-12-tetradecenyl acetate (E12- and Z12-14: OAc). These types could subsequently be characterized as four subtypes (A-D) depending on neural responses to pheromone components from various sister species of O. furnacalis, (Z)-9-, (E)-11- and (Z)-11- tetradecenyl acetate. The peripheral pheromone detection system of O. furnacalis is different to that of other moths. A large majority of the neurons investigated responded to both of the two principal pheromone components. Dose-response and cross-adaptation studies showed that olfactory receptor neurons with large amplitude action potentials responded equally well to E12- and Z12-14: OAc in sensillum types 1-3. Field experiments showed that O. furnacalis males are sensitive to ratios of E12- and Z12-14: OAc and that (Z)-9- tetradecenyl acetate acts as a behavioral antagonist. O. furnacalis males thus display an unusual coding system for odors involved in sexual communication, mainly built on less specific neurons, but still have the ability to detect and respond to the correct female blend. We hypothesize that the pheromone detection system of O. furnacalis consists of two parts, where one is devoted to high sensitivity to Delta 12 isomers of tetradecenyl acetate, E12- and Z12-14: OAc and the other to highly specific responses to the E12- or Z12-14: OAc. The unusual feature is thus that a large part of the system is devoted to sensitivity and only a minor part to selectivity. This could be explained by the fact that no other moth species are known to use E12- and/or Z12-14: OAc and that no strong selective pressure to increase selectivity between the isomers has been determined.
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| 4. |
- Anderbrant, O., et al.
(author)
-
Electrophysiological and morphological characteristics of pheromone receptors in male pine sawflies, Diprion pini (Hymenoptera : Diprionidae), and behavioural response to some compounds
- 1995
-
In: Journal of Insect Physiology. - : Elsevier BV. - 0022-1910. ; 41:5, s. 395-401
-
Journal article (peer-reviewed)abstract
- The morphology and physiology of pheromone receptors on the antennae of male pine sawflies, Diprion pini L., were investigated. Using scanning electron microscopy, five sensillar types were recognized. The type shown to be pheromone sensitive has a long (50-70 μm) cuticular hair, is single-walled, and is innervated by 8 or 9 sensory cells as revealed by transmission electron microscopy. Electroantennography (EAG) showed similar activity of the acetate and propionate of (2S,3R,7R)-3,7-dimethyl-2-tridecanol, precursor of the main constituent of the female-produced sex pheromone. No other isomer induced any significant response. Single-sensillum recordings confirmed the results of the EAG, and also showed that several neurons were excited by the active compound. EAG recordings and combined gas chromatographic-electroantennographic detection indicated that esters of three 3,7-dimethyl-2-pentadecanol (diprionol) isomers were active, but field tests could not demonstrate any behavioural effect. Diprionol esters are used as sex pheromones by all other pine sawflies investigated so far, and D. pini is thus the first diprionid species shown to use a different sex pheromone.
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| 5. |
- Andersson, Martin N, et al.
(author)
-
Antennal transcriptome analysis of the chemosensory gene families in the tree killing bark beetles, Ips typographus and Dendroctonus ponderosae (Coleoptera: Curculionidae: Scolytinae)
- 2013
-
In: BMC Genomics. - : Springer Science and Business Media LLC. - 1471-2164. ; 14
-
Journal article (peer-reviewed)abstract
- Background: The European spruce bark beetle, Ips typographus, and the North American mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae: Scolytinae), are severe pests of coniferous forests. Both bark beetle species utilize aggregation pheromones to coordinate mass-attacks on host trees, while odorants from host and non-host trees modulate the pheromone response. Thus, the bark beetle olfactory sense is of utmost importance for fitness. However, information on the genes underlying olfactory detection has been lacking in bark beetles and is limited in Coleoptera. We assembled antennal transcriptomes from next-generation sequencing of I. typographus and D. ponderosae to identify members of the major chemosensory multi-gene families. Results: Gene ontology (GO) annotation indicated that the relative abundance of transcripts associated with specific GO terms was highly similar in the two species. Transcripts with terms related to olfactory function were found in both species. Focusing on the chemosensory gene families, we identified 15 putative odorant binding proteins (OBP), 6 chemosensory proteins (CSP), 3 sensory neuron membrane proteins (SNMP), 43 odorant receptors (OR), 6 gustatory receptors (GR), and 7 ionotropic receptors (IR) in I. typographus; and 31 putative OBPs, 11 CSPs, 3 SNMPs, 49 ORs, 2 GRs, and 15 IRs in D. ponderosae. Predicted protein sequences were compared with counterparts in the flour beetle, Tribolium castaneum, the cerambycid beetle, Megacyllene caryae, and the fruit fly, Drosophila melanogaster. The most notable result was found among the ORs, for which large bark beetle-specific expansions were found. However, some clades contained receptors from all four beetle species, indicating a degree of conservation among some coleopteran OR lineages. Putative GRs for carbon dioxide and orthologues for the conserved antennal IRs were included in the identified receptor sets. Conclusions: The protein families important for chemoreception have now been identified in three coleopteran species (four species for the ORs). Thus, this study allows for improved evolutionary analyses of coleopteran olfaction. Identification of these proteins in two of the most destructive forest pests, sharing many semiochemicals, is especially important as they might represent novel targets for population control.
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| 6. |
- Anton, Sylvia, et al.
(author)
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Central nervous processing of sex pheromones in two strains of the European corn borer Ostrinia nubilalis (Lepidoptera : Pyralidae)
- 1997
-
In: Journal of Experimental Biology. - 0022-0949. ; 200:7, s. 1073-1087
-
Journal article (peer-reviewed)abstract
- Antennal lobe neurones were investigated in the pyralid moth Ostrinia nubilalis using intracellular recording and staining techniques. Response characteristics of antennal lobe neurones from males in the so-called E and Z strains, in F1 hybrids and in parental backcrosses were studied. The antennal lobe of a male O. nubilalis comprises approximately 30 ordinary glomeruli and three enlarged glomeruli making up the macroglomerular complex (MGC). Receptor neurones enter the antennal lobe via the antennal nerve and arborize in single glomeruli. Intracellularly stained, pheromone-responding projection neurones in both parental strains arborized in different glomeruli within the MGC, irrespective of their response characteristics. Neurones were grouped according to their specificity to single pheromone components and to pheromone blends. Component-specific, blend-specific and generalist neurones were found. Specificity only occurred at low stimulus concentrations and disappeared as concentrations increased. Although all neuronal types were present in both pheromone strains and crossings, differences in abundance and sensitivity were found. In the parental strains, neurones responding to the major pheromone component and to the respective strain-specific blend were more abundant than neurones responding to the minor component and the blend produced by the other strain. Neurones investigated in ZxE hybrids responded similarly to those of E-strain males, whereas neurones in EZxZ paternal backcrosses responded similarly to those of Z males. In the hybrids and paternal backcrosses, hybrid-blend-specific neurones were present that were not found in parental-strain males.
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| 7. |
- Anton, Sylvia, et al.
(author)
-
Developmental changes in the structure and function of the central olfactory system in gregarious and solitary desert locusts
- 2002
-
In: Microscopy Research and Technique. - : Wiley. - 1059-910X .- 1097-0029. ; 56:4, s. 281-291
-
Journal article (other academic/artistic)abstract
- Desert locusts are guided by olfactory cues in different behavioural contexts. In order to understand the basis for the variable olfactory guided behaviour displayed by different developmental stages and by solitary and gregarious locusts, we investigated their central olfactory system with neuroanatomical and neurophysiological methods. The primary olfactory centre of the brain, the antennal lobe (AL), increases in size during development due to an increased number and size of glomeruli. These glomeruli are innervated by a constant number of projection neurons that display increased dendritic arborizations during the development of the locust. The anatomical parameters do not differ between gregarious and solitary locusts, In parallel with the observed neuroanatomical changes, neurophysiological changes in response spectra and response specificity of AL neurons were found. During development, the percentage of neurons responding specifically to aggregation pheromone components decreases, whereas an increase in both pheromone-generalists and plant-pheromone generalist neurons is observed. The percentage of neurons responding to green leaf volatiles, however, remains constant. A decrease in the number of nymph blend-specific neurons was also observed. Our data show that anatomical and physiological properties of the AL and its neurons to a large extent reflect the changes in olfactory guided behaviour during development and between phases. The majority of our results are also in accordance with findings that the number of olfactory receptor neurons increases during development, resulting in increasing convergence on AL neurons.
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| 8. |
- Ayasse, Manfred, et al.
(author)
-
Evolution of reproductive strategies in the sexually deceptive orchid Ophrys sphegodes: How does flower-specific variation of odor signals influence reproductive success?
- 2000
-
In: Evolution. - 1558-5646. ; 54:6, s. 1995-2006
-
Journal article (peer-reviewed)abstract
- The orchid Ophrys sphegodes Miller is pollinated by sexually excited males of the solitary bee Andrena nigroaenea, which are lured to the flowers by visual cues and volatile semiochemicals. In O. sphegodes, visits by pollinators are rare. Because of this low frequency of pollination, one would expect the evolution of strategies that increase the chance that males will visit more than one flower on the same plant; this would increase the number of pollination events on a plant and therefore the number of seeds produced. Using gas chromatography-mass spectrometry (GC-MS) analyses, we identified more than 100 compounds in the odor bouquets of labellum extracts from O. sphegodes; 24 compounds were found to be biologically active in male olfactory receptors based on gas chromatography with electroantennographic detection (GC-EAD). Gas chromatography (GC) analyses of odors from individual flowers showed less intraspecific variation in the odor bouquets of the biologically active compounds as compared to nonactive compounds. This can be explained by a higher selective pressure on the pollinator-attracting communication signal. Furthermore, we found a characteristic variation in the GC-EAD active esters and aldehydes among flowers of different stem positions within an inflorescence and in the n-alkanes and n-alkenes among plants from different populations. In our behavioral field tests, we showed that male bees learn the odor bouquets of individual flowers during mating attempts and recognize them in later encounters. Bees thereby avoid trying to mate with flowers they have visited previously, but do not avoid other flowers either of a different or the same plant. By varying the relative proportions of saturated esters and aldehydes between flowers of different stem positions, we demonstrated that a plant may take advantage of the learning abilities of the pollinators and influence flower visitation behavior. Sixty-seven percent of the males that visited one flower in an inflorescence returned to visit a second flower of the same inflorescence. However, geitonogamy is prevented and the likelihood of cross-fertilization is enhanced by the time required for the pollinium deposited on the pollinator to complete its bending movement, which is necessary for pollination to occur. Cross-fertilization is furthermore enhanced by the high degree of odor variation between plants. This variation minimizes learned avoidance of the flowers and increases the likelihood that a given pollinator would visit several to many different plants within a population.
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| 9. |
- Baker, Thomas C., et al.
(author)
-
Adaptation of male moth antennal neurons in a pheromone plume is associated with cessation of pheromone-mediated flight
- 1989
-
In: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 14:3, s. 439-448
-
Journal article (peer-reviewed)abstract
- Recordings of the firing rates of single antennal neurons when Agrotis segetum antennac were placed 70 cm downwind of a pheromone source revealed that cells sensitive to the most volatile component adapted rapidly in a plume from a high-concentration source known from previous studies to cause in-flight arrestment of progress towards the source. No adaptation was found in response to lower-concentration plumes known to promote high levels of sustained flight to the source with little premature arrestment. Adaptation was not observed in antennal neurons of a second species, Heliothis virescens, when they were placed in plumes of this species' sex pheromone blend, regardless of the concentration. In flight-tunnel tests these same pheromone sources evoked high levels of source location with little arrestment. These results indicate that adaptation or attenuation of antennal neuronal burst frequencies in response to rapidly arriving pheromone filaments in a plume may be important peripheral determinants of whether or not prolonged upwind flight and successful pheromone source location occurs.
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| 10. |
- Bengtsson, Marie, et al.
(author)
-
Structure-activity relationships for chain-shortened analogs of (Z)-5-decenyl acetate, a pheromone component of the turnip moth, Agrotis segetum
- 1990
-
In: Journal of Chemical Ecology. - 0098-0331. ; 16:3, s. 667-684
-
Journal article (peer-reviewed)abstract
- Structure-activity relationships for chain-shortened analogs of (Z)-5-decenyl acetate, a pheromone component of the turnip moth, Agrotis segetum, have been studied by electrophysiological single-sensillum technique and interpreted in terms of a previously reported receptor-interaction model. The results indicate that the terminal methyl group, as well as the acetate group, interacts with highly complementary receptor sites. The terminal alkyl chain is suggested to interact with a hydrophobic "pocket" extending over the two methylene groups closest to the terminal methyl group. The amounts of stimulus actually released from the odor source have been studied. The results demonstrate the necessity to take differences of volatility into account in comparisons of electrophysiological data for compounds of different chain lengths. It is shown that relative vapor pressures may to a good approximation be employed to estimate correction factors.
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| 11. |
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| 12. |
- Bisch-Knaden, Sonja, et al.
(author)
-
Olfactory coding in five moth species from two families
- 2012
-
In: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 215:9, s. 1542-1551
-
Journal article (peer-reviewed)abstract
- The aim of the present study was to determine what impact phylogeny and life history might have on the coding of odours in the brain. Using three species of hawk moths (Sphingidae) and two species of owlet moths (Noctuidae), we visualized neural activity patterns in the antennal lobe, the first olfactory neuropil in insects, evoked by a set of ecologically relevant plant volatiles. Our results suggest that even between the two phylogenetically distant moth families, basic olfactory coding features are similar. But we also found different coding strategies in the moths' antennal lobe; namely, more specific patterns for chemically similar odorants in the two noctuid species than in the three sphingid species tested. This difference demonstrates the impact of the phylogenetic distance between species from different families despite some parallel life history traits found in both families. Furthermore, pronounced differences in larval and adult diet among the sphingids did not translate into differences in the olfactory code; instead, the three species had almost identical coding patterns.
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| 13. |
- Biswas, Twinkle, et al.
(author)
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Characterization of olfactory sensory neurons in the striped ambrosia beetle Trypodendron lineatum
- 2023
-
In: Frontiers in Physiology. - : Frontiers Media SA. - 1664-042X. ; 14
-
Journal article (peer-reviewed)abstract
- Introduction: The striped ambrosia beetle Trypodendron lineatum (Coleoptera, Curculionidae, Scolytinae) is a major forest pest in the Holarctic region. It uses an aggregation pheromone and host and non-host volatiles to locate suitable host trees, primarily stressed or dying conifer trees. The beetles bore into the xylem and inoculate spores of their obligate fungal mutualist Phialophoropsis ferruginea inside their excavated egg galleries, with the fungus serving as the main food source for the developing larvae. Olfactory sensory neuron (OSN) responses to pheromones and host volatiles are poorly understood in T. lineatum and other ambrosia beetles, and nothing is known about potential responses to fungal volatiles. Methods: We screened responses of OSNs present in 170 antennal olfactory sensilla using single sensillum recordings (SSR) and 57 odor stimuli, including pheromones, host and non-host compounds, as well as volatiles produced by P. ferruginea and fungal symbionts of other scolytine beetles. Results and Discussion: Thirteen OSN classes were characterized based on their characteristic response profiles. An OSN class responding to the aggregation pheromone lineatin was clearly the most abundant on the antennae. In addition, four OSN classes responded specifically to volatile compounds originating from the obligate fungal mutualist and three responded to non-host plant volatiles. Our data also show that T. lineatum has OSN classes tuned to pheromones of other bark beetles. Several OSN classes showed similar response profiles to those previously described in the sympatric bark beetle Ips typographus, which may reflect their shared ancestry.
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| 14. |
- Carlsson, Mikael A., et al.
(author)
-
Odour Maps in the Brain of Butterflies with Divergent Host-Plant Preferences
- 2011
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:8
-
Journal article (peer-reviewed)abstract
- Butterflies are believed to use mainly visual cues when searching for food and oviposition sites despite that their olfactory system is morphologically similar to their nocturnal relatives, the moths. The olfactory ability in butterflies has, however, not been thoroughly investigated. Therefore, we performed the first study of odour representation in the primary olfactory centre, the antennal lobes, of butterflies. Host plant range is highly variable within the butterfly family Nymphalidae, with extreme specialists and wide generalists found even among closely related species. Here we measured odour evoked Ca2+ activity in the antennal lobes of two nymphalid species with diverging host plant preferences, the specialist Aglais urticae and the generalist Polygonia c-album. The butterflies responded with stimulus-specific combinations of activated glomeruli to single plant-related compounds and to extracts of host and non-host plants. In general, responses were similar between the species. However, the specialist A. urticae responded more specifically to its preferred host plant, stinging nettle, than P. c-album. In addition, we found a species-specific difference both in correlation between responses to two common green leaf volatiles and the sensitivity to these compounds. Our results indicate that these butterflies have the ability to detect and to discriminate between different plant-related odorants.
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| 15. |
- Dweck, Hany K M, et al.
(author)
-
Olfactory Proxy Detection of Dietary Antioxidants in Drosophila.
- 2015
-
In: Current Biology. - : Elsevier BV. - 1879-0445 .- 0960-9822. ; 25:4, s. 455-466
-
Journal article (peer-reviewed)abstract
- Dietary antioxidants play an important role in preventing oxidative stress. Whether animals in search of food or brood sites are able to judge the antioxidant content, and if so actively seek out resources with enriched antioxidant content, remains unclear.
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| 16. |
- Ebrahim, Shimaa A M, et al.
(author)
-
Drosophila Avoids Parasitoids by Sensing Their Semiochemicals via a Dedicated Olfactory Circuit.
- 2015
-
In: PLoS Biology. - : Public Library of Science (PLoS). - 1545-7885. ; 13:12
-
Journal article (peer-reviewed)abstract
- Detecting danger is one of the foremost tasks for a neural system. Larval parasitoids constitute clear danger to Drosophila, as up to 80% of fly larvae become parasitized in nature. We show that Drosophila melanogaster larvae and adults avoid sites smelling of the main parasitoid enemies, Leptopilina wasps. This avoidance is mediated via a highly specific olfactory sensory neuron (OSN) type. While the larval OSN expresses the olfactory receptor Or49a and is tuned to the Leptopilina odor iridomyrmecin, the adult expresses both Or49a and Or85f and in addition detects the wasp odors actinidine and nepetalactol. The information is transferred via projection neurons to a specific part of the lateral horn known to be involved in mediating avoidance. Drosophila has thus developed a dedicated circuit to detect a life-threatening enemy based on the smell of its semiochemicals. Such an enemy-detecting olfactory circuit has earlier only been characterized in mice and nematodes.
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| 17. |
- Fan, Ruey-Jane, et al.
(author)
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Olfactory discrimination conditioning in the moth Spodoptera littoralis.
- 2001
-
In: Physiology & Behavior. - 1873-507X. ; 72:1-2, s. 159-165
-
Journal article (peer-reviewed)abstract
- We used a proboscis extension reflex (PER) to study the olfactory discrimination capability in the moth Spodoptera littoralis. Already after a single experience, moths were capable to discriminate a rewarded from an unrewarded odor. In the first experiment, when rewarded and unrewarded odors were substituted for each other, moths were able to undergo reversal conditioning already after two experiences. Both shorter and longer inter-trial intervals (ITIs) supported high degrees of learning. In a second experiment, moths could solve both feature-positive and -negative discrimination tasks. Two hypotheses for the way in which these associations exert their discrimination performance are considered. The moth's olfactory physiology has been extensively studied. This animal thus provides a powerful system in which to study the neurobiology of olfactory discrimination and odor recognition.
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| 18. |
- Gruber, Lydia, et al.
(author)
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Synaptic Spinules in the Olfactory Circuit of Drosophila melanogaster
- 2018
-
In: Frontiers in Cellular Neuroscience. - : Frontiers Media SA. - 1662-5102. ; 12
-
Journal article (peer-reviewed)abstract
- Here we report on ultrastructural features of brain synapses in the fly Drosophila melanogaster and outline a perspective for the study of their functional significance. Images taken with the aid of focused ion beam-scanning electron microscopy (EM) at 20 nm intervals across olfactory glomerulus DA2 revealed that some synaptic boutons are penetrated by protrusions emanating from other neurons. Similar structures in the brain of mammals are known as synaptic spinules. A survey with transmission EM (TEM) disclosed that these structures are frequent throughout the antennal lobe. Detailed neuronal tracings revealed that spinules are formed by all three major types of neurons innervating glomerulus DA2 but the olfactory sensory neurons (OSNs) receive significantly more spinules than other olfactory neurons. Double-membrane vesicles (DMVs) that appear to represent material that has pinched-off from spinules are also most abundant in presynaptic boutons of OSNs. Inside the host neuron, a close association was observed between spinules, the endoplasmic reticulum (ER) and mitochondria. We propose that by releasing material into the host neuron, through a process triggered by synaptic activity and analogous to axonal pruning, synaptic spinules could function as a mechanism for synapse tagging, synaptic remodeling and neural plasticity. Future directions of experimental work to investigate this theory are proposed.
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| 19. |
- Hallberg, Eric, et al.
(author)
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Sensilla and Proprioceptors
- 2003
-
In: Handbook of Zoology, Vol. IV. Part 36. Lepidoptera, moths and butterflies. Vol. 2., Morphology, physiology, and development.. - 3110162105 ; , s. 267-288
-
Book chapter (other academic/artistic)abstract
- Abstract is not available
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| 20. |
- Hallberg, Eric, et al.
(author)
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Sensilla and proprioceptors
- 2003
-
In: Lepidoptera, Moths and Butterflies : Volume 2: Morphology, Physiology, and Development - Volume 2: Morphology, Physiology, and Development. - : DE GRUYTER. - 9783110893724 - 3110162105 - 9783110162103 ; , s. 267-288
-
Book chapter (peer-reviewed)
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| 21. |
- Hansson, Bill S., et al.
(author)
-
Electrophysiological and chemical analysis of sex pheromone communication system of the mottled umber, Erannis defoliaria (Lepidoptera : Geometridae)
- 1990
-
In: Journal of Chemical Ecology. - 0098-0331. ; 16:6, s. 1887-1897
-
Journal article (peer-reviewed)abstract
- (Z,Z,Z)-3,6,9-nonadecatriene (Z3, Z6, Z9-19Hy) and (Z,Z)-3,9-cis-6,7-epoxy-nonadecadiene (Z3, Z9-cis-6,7-epo-19Hy) were identified in pheromone gland extracts from female Erannis defoliaria. The two components were found in a 1:3 ratio, with the main component, Z3, Z9-cis-6,7-epo-19Hy present at an amount of about 1.5 ng per female. The components were identified by means of gas chromatography-mass spectrometry, gas chromatography-electroantennography and gas chromatography-single sensillum recordings. Single sensillum measurements on the male antenna showed two physiological types of sensilla. One type was characterized by a large spike amplitude cell responding to Z3, Z9-cis-6,7-epoxy-19Hy and a small spike amplitude cell responding to Z3, Z6, Z9-19Hy. A second type responded only with a large spike amplitude cell to the epoxide, and this cell was inhibited by the triene. Of the two pheromone components, the epoxide gave the higher response in the EAG tests. Preliminary field tests support the identification of the pheromone components. The epoxide was also found to be present in the extract of the pheromone gland of Colotois pennaria, and males of C. pennaria and Agriopis marginaria were trapped by the mixture of the identified compounds.
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| 22. |
- Hansson, Bill S, et al.
(author)
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Function and Morphology of the Antennal Lobe: New Developments
- 2000
-
In: Annual Review of Entomology. - : Annual Reviews. - 0066-4170 .- 1545-4487. ; 45, s. 203-231
-
Journal article (other academic/artistic)abstract
- The antennal lobe of insects has emerged as an excellent model for olfactory processing in the CNS. In the present review we compile data from areas where substantial progress has been made during recent years: structure-function relationships within the glomerular array, integration and blend specificity, time coding and the effects of neuroactive substances and hormones on antennal lobe processing.
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| 23. |
- Hansson, Bill S., et al.
(author)
-
Functional specialization of olfactory glomeruli in a moth
- 1992
-
In: Science. - 0036-8075. ; 256:5061, s. 1313-1315
-
Journal article (peer-reviewed)abstract
- The specific function of the glomerular structures present in the antennal lobes or olfactory bulbs of organisms ranging from insects to humans has been obscure because of limitations in neuronal marking methods. By tracing individual neurons in the moth Agrotis segetum, it was determined that physiologically distinct types of pheromone receptor neurons project axons to different regions of the macroglomerular complex (MGC). Each glomerulus making up the MGC has a specific functional identity, initially processing information about one specific pheromone component. This indicates that, at least through the first stage of synapses, olfactory information moves through labeled lines.
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| 24. |
- Hansson, Bill S., et al.
(author)
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Pheromone variation among eastern European and a western Asian population of the turnip moth Agrotis segetum
- 1990
-
In: Journal of Chemical Ecology. - 0098-0331. ; 16:5, s. 1611-1622
-
Journal article (peer-reviewed)abstract
- The female sex pheromone composition and the male electro-physiological response with respect to the three main sex pheromone components, (Z)-5-decenyl acetate, (Z)-7-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, were investigated in populations of Agrotis segetum from Armenia and Bulgaria. The percentage composition of the female-produced pheromone was 1:52:47 and 1:42:57 for the respective populations. Corresponding male receptor frequencies were 9:90:1 and 6:92:2. EAG response profiles of the male antennae were similar for the two populations. The populations from Armenia and Bulgaria differed from the earlier investigated French and Swedish populations, which have larger amounts of (Z)-5-decenyl acetate in gland extracts and have a majority of (Z)-5-decenyl acetate-sensitive receptors. Investigation of receptor frequencies on antennae of male Hungarian moths showed that individuals could be classified as either Swedish or Armenian/Bulgarian type. Males of the Swedish type were preferentially attracted to the three-component pheromone blend, whereas blends of (Z)-7-dodecenyl and (Z)-9-tetradecenyl acetate, and (Z)-7-dodecenol [pure or in mixture with (Z)-5-decenol] attracted the Armenian/Bulgarian type. The nature of pheromone variation among European and Asian populations of the turnip moth and possible mechanisms maintaining the variation are discussed.
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| 25. |
- Hansson, Bill S., et al.
(author)
-
Z‐linked inheritance of male olfactory response to sex pheromone components in two species of tortricid moths, Ctenopseustis obliquana and Ctenopseustis sp
- 1989
-
In: Entomologia Experimentalis et Applicata. - : Wiley. - 0013-8703. ; 53:2, s. 137-145
-
Journal article (peer-reviewed)abstract
- The olfactory response from male pheromone sensitive sensilla was investigated in the endemic New Zealand brownheaded leafrollers Ctenopseustis obliquana (Walker) and C. sp. ‘ropeana' (Lepidoptera, Tortricidae). The responses from 281 sensilla from the parental strains and from both the reciprocal crosses, including F1, F2 and maternal and paternal backcrosses were recorded, and statistically analysed using a multivariate analysis. In males of both the parental strains, a large amplitude cell responded to the main pheromone component of the conspecific female, in C. obliquana (Z)‐8‐tetradecenyl acetate (Z8–14:OAc) and in C. sp ‘ropeana' (Z)‐5‐tetradecenyl acetate (Z5–14:OAc). Both male types also possessed a small amplitude cell, which in C. obliquana responded weakly to Z5–14: OAc and tetradecyl acetate (14: OAc), and in C. sp ‘ropeana' responded to Z8–14: OAc. The responses from the different types of hybrid males were more variable than the responses from parental males. A main pattern could, however be seen, corresponding with the expected pattern in a sex‐linked inheritance on the Z‐chromosome of a C. sp ‘ropeana' type dominant genetic factor. The more pronounced variation in the hybrids could not be explained by this model, and might be due to the involvement of additional genes. Liaison avec le chromosome Z de l'hérédité des réponses olfactives à la composition de la phéromone sexuelle chez deux tordeuses: Ctenopseustis obliquana et C. sp. ‘ropeana' Les réactions olfactives des sensilles mâles sensibles aux phéromones ont été examinées par enregistrement de l'extrémité de la sensille chez les tordeuses C. obliquana Walker et C. sp. ‘ropeana'. Les enregistrements ont porté sur 281 sensilles des lignées parentales et des croisements réciproques de F1, F2 et de croisements en retour maternel et paternel. Les résultats des enregistrements d'une sensille ont été soumis à une analyse en composantes principales. Chez les mâles de chaque lignée parentale un seul type physiologique de sensille a été découvert; une cellule répond par un pic grand au principal constituant de la phéromone femelle conspécifïque. (Z)‐8‐acétate tétradécényl (Z8–14:OAc) pour C. obliquana, et (Z)‐5‐acétate tétradécényl (Z5–14:OAc) pour C. sp. ‘ropeana'. Une seconde type de cellule dans les sensilles des deux espèces de mâles présente un pic petit pour Z5–14: OAc et pour l'acétate tétradécyl (14: OAc) chez C. obliquana, et pour C. sp. ‘ropeana' au Z8–14:OAc. Les réponses des sensilles des différents types de mâles hybrides sont plus hétérogènes que celles des sensilles de leurs pères. Un schéma général pourrait cependant être décelé, correspondant au schéma prévu avec une hérédité d'un facteur dominant liée au sexe sur le chromosome Z de C. sp. ‘ropeana’. La variation plus accentuée chez les hybrides ne peut être expliquée par ce modèle, et pourrait impliquer des gènes additionnels. 1989 The Netherlands Entomological Society
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| 26. |
- Harzsch, Steffen, et al.
(author)
-
Local olfactory interneurons provide the basis for neurochemical regionalization of olfactory glomeruli in crustaceans
- 2022
-
In: Journal of Comparative Neurology. - : Wiley. - 0021-9967 .- 1096-9861. ; 530:9, s. 1399-1422
-
Journal article (peer-reviewed)abstract
- The primary olfactory centers of metazoans as diverse as arthropods and mammals consist of an array of fields of dense synaptic neuropil, the olfactory glomeruli. However, the neurochemical structure of crustacean olfactory glomeruli is largely understudied when compared to the insects. We analyzed the glomerular architecture in selected species of hermit crabs using immunohistochemistry against presynaptic proteins, the neuropeptides orcokinin, RFamide and allatostatin, and the biogenic amine serotonin. Our study reveals an unexpected level of structural complexity, unmatched by what is found in the insect olfactory glomeruli. Peptidergic and aminergic interneurons provide the structural basis for a regionalization of the crustacean glomeruli into longitudinal and concentric compartments. Our data suggest that local olfactory interneurons take a central computational role in modulating the information transfer from olfactory sensory neurons to projection neurons within the glomeruli. Furthermore, we found yet unknown neuronal elements mediating lateral inhibitory interactions across the glomerular array that may play a central role in modulating the transfer of sensory input to the output neurons through presynaptic inhibition. Our study is another step in understanding the function of crustacean olfactory glomeruli as highly complex units of local olfactory processing.
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| 27. |
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| 28. |
- Ignell, Rickard, et al.
(author)
-
The Antennal Lobe of Orthoptera - Anatomy and Evolution
- 2001
-
In: Brain, Behavior and Evolution. - : S. Karger AG. - 0006-8977 .- 1421-9743. ; 57:1, s. 1-17
-
Journal article (other academic/artistic)abstract
- The first odor-processing neuropils of insects comprise glomeruli, islets of neuropil, that are supplied by olfactory receptor neurons and give rise to efferent axons to higher brain centers. Glomeruli size and organization varies in a taxon-specific manner across the Insecta, suggesting possible correlates between their organization and chemosensory behaviors in different insect groups. Comparative studies of antennal lobe glomeruli within the Orthoptera have been used to infer how the various taxon-specific arrangements of odorant-processing structures (glomeruli) might have evolved. The cellular arrangements in glomeruli have been surveyed using anterograde filling and Golgi impregnation of antennal receptor neurons projecting to the antennal lobe in Stenopelmatidae, Tettigoniidae, Gryllidae, Tetrigidae and Acrididae. These taxa, which represent the two sub-orders of Orthoptera, reveal a high correlation between the neural architecture of the glomeruli and structures within the glomeruli. Using a recent molecular phylogeny of the Orthoptera we have mapped the occurrence of glomerular characteristics to infer the evolution of antennal lobe structures in orthopterans. The functional implications of these results are discussed.
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| 29. |
- Ignell, Rickard, et al.
(author)
-
The maxillary palp sensory pathway of Orthoptera
- 2001
-
In: Arthropod Structure & Development. - 1467-8039. ; 29:4, s. 295-305
-
Journal article (peer-reviewed)abstract
- Primary sensory projections and arborisations of higher-order neurons associated with the maxillary palps were examined in Tettigoniidae, Gryllidae, Tetrigidae and Acrididae representing the two sub-orders of Orthoptera, Ensifera and Caelifera. Anterograde filling and Golgi impregnation of maxillary receptor neurons revealed two patterns of innervation, the ensiferous and the caeliferous type. In both ensiferans and caeliferans, receptor neurons arborised within the tritocerebrum, the antennal motor- and mechano-sensory centre and the lobus glomerulatus. In ensiferans, additional areas of innervation were found in the lobus glomerulatus and in a previously undescribed neuropil, here referred to as the accessory lobus glomerulatus. In relation to the anatomical data a putative functional segregation of the neuropil into gustatory-, olfactory- and mechano-sensory centres is implied.
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| 30. |
- Khallaf, Mohammed A., et al.
(author)
-
Mate discrimination among subspecies through a conserved olfactory pathway
- 2020
-
In: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 6:25
-
Journal article (peer-reviewed)abstract
- Communication mechanisms underlying the sexual isolation of species are poorly understood. Using four subspecies of Drosophila mojavensis as a model, we identify two behaviorally active, male-specific pheromones. One functions as a conserved male antiaphrodisiac in all subspecies and acts via gustation. The second induces female receptivity via olfaction exclusively in the two subspecies that produce it. Genetic analysis of the cognate receptor for the olfactory pheromone indicates an important role for this sensory pathway in promoting sexual isolation of subspecies, in combination with auditory signals. Unexpectedly, the peripheral sensory pathway detecting this pheromone is conserved molecularly, physiologically, and anatomically across subspecies. These observations imply that subspecies-specific behaviors arise from differential interpretation of the same peripheral cue, reminiscent of sexually conserved detection but dimorphic interpretation of male pheromones in Drosophila melanogaster. Our results reveal that, during incipient speciation, pheromone production, detection, and interpretation do not necessarily evolve in a coordinated manner.
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| 31. |
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| 32. |
- Kristoffersen, Lina, et al.
(author)
-
Aglomerular hemipteran antennal lobes – Basic neuroanatomy of a small nose
- 2008
-
In: Chemical Senses. - : Oxford University Press (OUP). - 1464-3553 .- 0379-864X. ; 33, s. 771-778
-
Journal article (peer-reviewed)abstract
- We have compared the basic organization of the primary olfactory centre, the antennal lobe (AL), in 4 hemipteran species representing the 2 major lineages in this order. The Homoptera were represented by the psyllid Trioza apicalis and its aphid relatives the grain aphid Sitobion avenae Fabricius and the rose-grain aphid Metopolophium dirhodum Walker, whereas the Heteroptera were represented by the pentatomid stink bug Euschistus heros Fabricius. The olfactory systems of psyllids and aphids are generally very small, with low numbers of afferents in comparison to other insect groups, and the smallest described so far belongs to T. apicalis, comprising less than 50 olfactory receptor neurons (ORNs). Originally, we tried to estimate numbers of olfactory glomeruli in the AL of T. apicalis, which in insects generally correspond closely to the number of different types of ORNs. Neither immunocytochemical staining nor anterograde staining of ORNs revealed any glomerular structures in the ALs of T. apicalis or the 2 aphids that were included for comparison. In contrast, the ALs of the pentatomid stink bug E. heros displayed numerous distinct and well-delineated glomeruli, showing that aglomerular ALs are not typical of all insects within the order Hemiptera. Glomeruli are hallmark features of olfactory lobes in many different phyla, and the absence of glomerular structures in psyllids and aphids appears to be unique in insects that depend on olfactory orientation.
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| 33. |
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| 34. |
- Krång, Anna Sara, 1972, et al.
(author)
-
Transition from sea to land: Olfactory function and constraints in the terrestrial hermit crab Coenobita clypeatus
- 2012
-
In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 279:1742, s. 3510-3519
-
Journal article (peer-reviewed)abstract
- The ability to identify chemical cues in the environment is essential to most animals. Apart from marine larval stages, anomuran land hermit crabs (Coenobita) have evolved different degrees of terrestriality, and thus represent an excellent opportunity to investigate adaptations of the olfactory system needed for a successful transition from aquatic to terrestrial life. Although superb processing capacities of the central olfactory system have been indicated in Coenobita and their olfactory system evidently is functional on land, virtually nothing was known about what type of odourants are detected. Here, we used electroantennogram (EAG) recordings in Coenobita clypeatus and established the olfactory response spectrum. Interestingly, different chemical groups elicited EAG responses of opposite polarity, which also appeared for Coenobita compressus and the closely related marine hermit crab Pagurus bernhardus. Furthermore, in a two-choice bioassay with C. clypeatus, we found that water vapour was critical for natural and synthetic odourants to induce attraction or repulsion. Strikingly, also the physiological response was found much greater at higher humidity in C. clypeatus, whereas no such effect appeared in the terrestrial vinegar fly Drosophila melanogaster. In conclusion, our results reveal that the Coenobita olfactory system is restricted to a limited number of water-soluble odourants, and that high humidity is most critical for its function.
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| 35. |
- Larsson, Mattias C, et al.
(author)
-
Specialized olfactory receptor neurons mediating intra- and interspecific chemical communication in leafminer moths Eriocrania spp. (Lepidoptera: Eriocraniidae).
- 2002
-
In: Journal of Experimental Biology. - 1477-9145. ; 205:7, s. 989-998
-
Journal article (peer-reviewed)abstract
- We performed a physiological and morphological characterization of sensilla auricillica in male Eriocrania semipurpurella moths. Each auricillic sensillum contained three olfactory receptor neurons. Responding neurons (87 of 139) could be grouped into five physiological types. Type 1 responded to (R,Z)-6-nonen-2-ol and type 2 to its enantiomer (S,Z)-6-nonen-2-ol, both of which are pheromone components of E. semipurpurella. Type 3 responded to both (R)-heptan-2-ol and (R,Z)-4-hepten-2-ol, which are pheromone components of the sympatric species E. cicatricella. Types 4 and 5 responded to the ketones (Z)-6-nonen-2-one and/or nonan-2-one, which are found in the pheromone glands of female E. semipurpurella. Field-trapping showed that type 3 receptor neurons mediate strongly antagonistic effects of (R)-heptan-2-ol and (R,Z)-4-hepten-2-ol on E. semipurpurella, while nonan-2-one should possibly be included as a synergist in the sex pheromone blend of this species. The attraction of E. cicatricella and E. sparrmannella to compounds mixed with the pheromone blend of E. semipurpurella shows that the pheromone components of E. semipurpurella have little or no antagonistic effects on these species. The morphology and physiology of eriocraniid pheromone sensilla are very similar to those found in the order Trichoptera (caddisflies), suggesting a homology between pheromone detection systems in the two sister orders Lepidoptera and Trichoptera.
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| 36. |
- Lebreton, Sebastien, et al.
(author)
-
A Drosophila female pheromone elicits species-specific long-range attraction via an olfactory channel with dual specificity for sex and food
- 2017
-
In: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 15:1
-
Journal article (peer-reviewed)abstract
- Background: Mate finding and recognition in animals evolves during niche adaptation and involves social signals and habitat cues. Drosophila melanogaster and related species are known to be attracted to fermenting fruit for feeding and egg-laying, which poses the question of whether species-specific fly odours contribute to long-range premating communication. Results: We have discovered an olfactory channel in D. melanogaster with a dual affinity to sex and food odorants. Female flies release a pheromone, (Z)-4-undecenal (Z4-11Al), that elicits flight attraction in both sexes. Its biosynthetic precursor is the cuticular hydrocarbon (Z,Z)-7,11-heptacosadiene (7,11-HD), which is known to afford reproductive isolation between the sibling species D. melanogaster and D. simulans during courtship. Twin olfactory receptors, Or69aB and Or69aA, are tuned to Z4-11Al and food odorants, respectively. They are co-expressed in the same olfactory sensory neurons, and feed into a neural circuit mediating species-specific, long-range communication; however, the close relative D. simulans, which shares food resources with D. melanogaster, does not respond to Z4-11Al. Conclusion: The Or69aA and Or69aB isoforms have adopted dual olfactory traits. The underlying gene yields a collaboration between natural and sexual selection, which has the potential to drive speciation.
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| 37. |
- Lei, H, et al.
(author)
-
Olfactory protocerebral pathways processing sex pheromone and plant odor information in the male moth Agrotis segetum
- 2001
-
In: Journal of Comparative Neurology. - : Wiley. - 1096-9861 .- 0021-9967. ; 432:3, s. 356-370
-
Journal article (peer-reviewed)abstract
- We investigated protocerebral processing of behaviorally relevant signals in the turnip moth, Agrotis segetum. Single neurons were studied both physiologically and morphologically using intracellular recording techniques. In moth pheromone communication systems, the presence of the complete, female-produced pheromone blend is necessary for male attraction. We predicted that more protocerebral neurons, compared with AL, would display blend interactions. However, only a few protocerebral neurons responded differently to the blend than could be deduced from the response to single components. The majority of the pheromone-sensitive protocerebral neurons identified in this study responded to the major pheromone component. In coding time, most AL neurons can follow a 5-Hz odor stimulus, whereas most protocerebral neurons failed at higher frequencies than 1 Hz. The majority of neurons that responded to the odorants tested innervated one or both of the protocerebral lateral accessory lobes. If only one of these was innervated, then the innervation always displayed a varicose appearance, suggesting a presynaptic function. Thus, information seems to be transferred from other protocerebral areas to the lateral accessory lobes. Into these, descending neurons sent smooth, postsynaptic branches. A majority of the neurons innervating the superior medial protocerebrum were found to display single-component specificity. Few additional correlations between odor specificity and structural characteristics were apparent.
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| 38. |
- Lofstedt, Christer, et al.
(author)
-
Pheromone dialects in European turnip moths Agrotis segetum
- 1986
-
In: Oikos. - : JSTOR. - 0030-1299. ; 46:2, s. 250-257
-
Journal article (peer-reviewed)abstract
- Female pheromone gland extracts from cultures of Agrotis segetum originating from Sweden, France, Hungary and England were analysed for pheromone components and precursors (fatty acids). The pheromone blends were similar in moths from the Swedish, English and Hungarian populations, whereas the French diverged with a much higher amount of (Z)-7-decenyl acetate relative to the homologous pheromone components (Z)-7-dodecenyl acetate and (Z)-9-tetradecenyl acetate. -from Authors
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| 39. |
- Löfstedt, Christer, et al.
(author)
-
Behavioural and electrophysiological activity of unsaturated analogues of the pheromone tetradecyl acetate in the small ermine moth Yponomeuta rorellus
- 1990
-
In: Physiological Entomology. - : Wiley. - 0307-6962 .- 1365-3032. ; 15:1, s. 47-54
-
Journal article (peer-reviewed)abstract
- ABSTRACT In field‐trapping experiments the unsaturated analogues (E)‐6‐, (E)‐12‐, and (Z)‐12‐tetradecenyl acetate were as attractive to male Yponomeuta rorellus Latr. as the native pheromone component tetradecyl acetate. All four analogues attracted more males than virgin females did, whereas (Z)‐6‐, (E)‐11‐, (Z)‐10‐ and (Z)‐11‐tetradecenyl acetate were essentially non‐attractive. Addition of 1–30% of (Z)‐11‐tetradecenyl acetate to the pheromone tetradecyl acetate reduced the attraction to less than 2%. Flight tunnel experiments with Y. rorellus confirmed the activity of the (E)‐6‐ and (E)‐12‐tetradecenyl acetates and demonstrated the activity of (E)‐7‐tetradecenyl acetate as well. These analogues elicited orientation behaviour, upwind flight and landing at the odour source as frequently as the native pheromone did. Single sensillum recordings from male Y. rorellus showed two types of cells in most sensilla. A large spike amplitude cell was stimulated by tetradecyl acetate and the unsaturated analogues (E)‐11‐, (E)‐6‐ and (E)‐12‐tetradecenyl acetate, and to a lower extent by the (Z)‐6‐, (Z)‐11‐ and (Z)‐12‐isomers. A cell with medium spike amplitude was stimulated by (Z)‐9‐tetradecenyl and (Z)‐11‐hexadecenyl acetate. Some sensilla contained a third cell firing with a small spike amplitude which was activated by (Z)‐11‐tetradecenol. Thus the tetradecyl acetate receptor was stimulated not only by the behaviourally active analogues, but also by behavioural antagonists. The interaction of (E)‐11‐tetra‐decenyl acetate and tetradecyl acetate with the same antennal receptor cell was also demonstrated in Y.cagnagellus. Electrophysiological discrimination between behavioural attractants and antagonists and the role of behavioural antagonists in the interspecific relations between Y.rorellus and sympatric closely related species are discussed.
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| 40. |
- Löfstedt, Christer, et al.
(author)
-
Jan Löfqvist - minnesteckning
- 2007
-
In: Årsbok 2005-2006. - 1402-1277. ; , s. 133-137
-
Book chapter (pop. science, debate, etc.)
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| 41. |
- Löfstedt, Christer, et al.
(author)
-
No linkage between genes controlling female pheromone production and male pheromone response in the European corn borer, Ostrinia nubilalis Hübner (Lepidoptera; Pyralidae).
- 1989
-
In: Genetics. - 0016-6731. ; 123:3, s. 553-556
-
Journal article (peer-reviewed)abstract
- The E and Z pheromonal strains of the European corn borer, Ostrinia nubilalis, are characterized by female production of and male preference for opposite blends of (E)-11-and (Z)-11-tetradecenyl acetate. It is known that the pheromone production is controlled by an autosomal gene and that the males' behavior is determined by a sex-linked gene. A third gene, autosomally inherited, has been shown to determine the organization of the male pheromone receptors. In the present study the linkage relationship between the autosomal genes controlling sex pheromone production and male olfactory sensilla was investigated. A recombination experiment showed unequivocally that the genes determining the variation in pheromone production and male pheromone receptors are not closely linked and are most likely inherited independently.
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| 42. |
- Löfstedt, Christer, et al.
(author)
-
Pheromonal secretions from glands on the 5th abdominal sternite of hydropsychid and rhyacophilid caddisflies (Trichoptera)
- 1994
-
In: Journal of Chemical Ecology. - 0098-0331. ; 20:1, s. 153-170
-
Journal article (peer-reviewed)abstract
- Extracts of different body parts of adult Trichoptera were tested for electrophysiological activity. Extracts of the IVth and Vth abdominal sternites of female Hydropsyche angustipennis, Rhyacophila nubila, and R. fasciata, containing a paired exocrine gland, elicited significant electroan-tennographic responses when tested on conspecific male antennae. The paired gland occurs also in males of all the species, and in H. angustipennis, extracts from males were more active than female extracts when tested on male antennae. Female and male extracts from all species were analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). EAD-active peaks in female extracts, stimulating male antennae, were identified in H. angustipennis as nonan-2-one; and in R. nubila and R. fasciata as heptan-2-one, heptan-2-ol, nonan-2-one, and nonan-2-ol. EAD-active components from male H. angustipennis stimulating male antennae were octan-2-one, nonan-2-one (major peak), (Z)-6-nonen-2-one, decan-2-one, and a methylbranched decan-2-one. Female extracts and synthetic mixtures of compounds identified from female H. angustipennis and R. fasciata were tested for attractivity in the field. High catches with control traps obscured the results, but a synthetic mixture of the four identified compounds was significantly attractive and not different from female extracts for attracting male R. fasciata. In H. angustipennis, a synthetic six-component male blend, in which nonan-2-one was the major component, attracted significant numbers of male and female H. angustipennis. Extracts of male R. nubila and R. fasciata contained acetophenone and hexanoic and octanoic acids but did not have any electrophysiological or behavioral activity on either male or female antennae of conspecifics. The occurrence of a female sex pheromone in Rhyacophila and an aggregation pheromone in Hydropsyche corresponds to earlier described differences in mating behaviors in the Rhyacophilidae and Hydropsychidae.
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| 43. |
- Löfstedt, Christer, et al.
(author)
-
Pheromone differences between sibling taxa Diachrysia chrysitis (linnaeus, 1758) and D. tutti (Kostrowicki, 1961) (Lepidoptera Noctuidae)
- 1994
-
In: Journal of Chemical Ecology. - 0098-0331. ; 20:1, s. 91-109
-
Journal article (peer-reviewed)abstract
- The noctuid sibling taxa Diachrysia chrysitis s. str. and D. tutti, of yet uncertain taxonomic status, have previously been shown to possess differences in morphology and to be attracted to different mixtures of the two presumed pheromone components (Z)-5-decenyl acetate and (Z)-7-decenyl acetate. Typical D. tutti males (clearly broken forewing marking) are known to respond to a 2: 100 mixture of the two isomers, whereas D. chrysitis males (unbroken marking) are attracted to a 100: 10 mixture. We investigated female pheromone production and male electroantennographic (EAG) response in Diachrysia families raised in the laboratory from field-collected gravid females. Extracts of individual females from typical D. tutti and D. chrysitis families were subjected to gas chromatography with simultaneous flame ionization and electroantennographic detection. All females produced mixtures of Z5- and Z7-10:OAc, but female D. chrysitis produced predominantly Z5-10:OAc and the antennae of their brothers responded more strongly to the Z5 peak than to the Z7-10:OAc peak, whereas the opposite was true for D. tutti families. The pheromone components were shown to be biosynthesized from hexadecanoic and tetradecanoic acid, respectively by Z11-desaturation followed by chain shortening, reduction, and acetylation. The EAG responses of males trapped with the typical D. tutti and D. chrysitis blends, as well as with an intermediate blend, were investigated. Males trapped with the D. tutti mixture almost exclusively had a clearly broken wing marking and showed strongest EAG response to Z7-10:OAc. The intermediate blend and the D. chrysitis mixture gave more mixed catches, but with a prevalence of males with an unbroken (or almost unbroken) wing marking and with a higher mean response to Z5-10:OAc. Some males with typical D. tutti EAG responses were attracted in the field to the D. chrysitis pheromone. In the flight tunnel some D. chrysitis males were attracted also to the D. tutti mixture. This indicates that cross attraction may take place between the two taxa under natural conditions.
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| 44. |
- Majid, Asifa, et al.
(author)
-
Olfactory language and abstraction across cultures
- 2018
-
In: Philosophical Transactions of the Royal Society B: Biological Sciences. - : The Royal Society. - 1471-2970 .- 0962-8436. ; 373:1752
-
Journal article (peer-reviewed)abstract
- Olfaction presents a particularly interesting arena to explore abstraction in language. Like other abstract domains, such as time, odours can be difficult to conceptualize. An odour cannot be seen or held, it can be difficult to locate in space, and for most people odours are difficult to verbalize. On the other hand, odours give rise to primary sensory experiences. Every time we inhale we are using olfaction to make sense of our environment. We present new experimental data from 30 Jahai huntergatherers from the Malay Peninsula and 30 matched Dutch participants from the Netherlands in an odour naming experiment. Participants smelled monomolecular odorants and named odours while reaction times, odour descriptors, and facial expressions were measured. We show that while Dutch speakers relied on concrete descriptors, i.e. they referred to odour sources (e.g. smells like lemon), the Jahai used abstract vocabulary to name the same odours (e.g. musty). Despite this differential linguistic categorization, analysis of facial expressions showed that the two groups, nevertheless, had the same initial emotional reactions to odours. Critically, these cross-linguistic data present a challenge for how to think about abstraction in language.
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| 45. |
- Polanska, Martha A., et al.
(author)
-
Functional morphology of the primary olfactory centers in the brain of the hermit crab Coenobita clypeatus (Anomala, Coenobitidae)
- 2020
-
In: Cell and Tissue Research. - : Springer Science and Business Media LLC. - 0302-766X .- 1432-0878. ; 380:3, s. 449-467
-
Journal article (peer-reviewed)abstract
- Terrestrial hermit crabs of the genus Coenobita display strong behavioral responses to volatile odors and are attracted by chemical cues of various potential food sources. Several aspects of their sense of aerial olfaction have been explored in recent years including behavioral aspects and structure of their peripheral and central olfactory pathway. Here, we use classical histological methods and immunohistochemistry against the neuropeptides orcokinin and allatostatin as well as synaptic proteins and serotonin to provide insights into the functional organization of their primary olfactory centers in the brain, the paired olfactory lobes. Our results show that orcokinin is present in the axons of olfactory sensory neurons, which target the olfactory lobe. Orcokinin is also present in a population of local olfactory interneurons, which may relay lateral inhibition across the array of olfactory glomeruli within the lobes. Extensive lateral connections of the glomeruli were also visualized using the histological silver impregnation method according to Holmes-Blest. This technique also revealed the structural organization of the output pathway of the olfactory system, the olfactory projection neurons, the axons of which target the lateral protocerebrum. Within the lobes, the course of their axons seems to be reorganized in an axon-sorting zone before they exit the system. Together with previous results, we combine our findings into a model on the functional organization of the olfactory system in these animals.
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| 46. |
- Roberts, Rebecca E., et al.
(author)
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Odorant receptor orthologues in conifer-feeding beetles display conserved responses to ecologically relevant odours
- 2022
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In: Molecular Ecology. - : Wiley. - 0962-1083 .- 1365-294X. ; 31:13, s. 3693-3707
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Journal article (peer-reviewed)abstract
- Insects are able to detect a plethora of olfactory cues using a divergent family of odorant receptors (ORs). Despite the divergent nature of this family, related species frequently express several evolutionarily conserved OR orthologues. In the largest order of insects, Coleoptera, it remains unknown whether OR orthologues have conserved or divergent functions in different species. Using HEK293 cells, we addressed this question through functional characterization of two groups of OR orthologues in three species of the Curculionidae (weevil) family, the conifer-feeding bark beetles Ips typographus L. (“Ityp”) and Dendroctonus ponderosae Hopkins (“Dpon”) (Scolytinae), and the pine weevil Hylobius abietis L. (“Habi”; Molytinae). The ORs of H. abietis were annotated from antennal transcriptomes. The results show highly conserved response specificities, with one group of orthologues (HabiOR3/DponOR8/ItypOR6) responding exclusively to 2-phenylethanol (2-PE), and the other group (HabiOR4/DponOR9/ItypOR5) responding to angiosperm green leaf volatiles (GLVs). Both groups of orthologues belong to the coleopteran OR subfamily 2B, and share a common ancestor with OR5 in the cerambycid Megacyllene caryae, also tuned to 2-PE, suggesting a shared evolutionary history of 2-PE receptors across two beetle superfamilies. The detected compounds are ecologically relevant for conifer-feeding curculionids, and are probably linked to fitness, with GLVs being used to avoid angiosperm nonhost plants, and 2-PE being important for intraspecific communication and/or playing a putative role in beetle–microbe symbioses. To our knowledge, this study is the first to reveal evolutionary conservation of OR functions across several beetle species and hence sheds new light on the functional evolution of insect ORs.
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| 47. |
- Ruebenbauer, Agnieszka, et al.
(author)
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Genetic variability and robustness of host odor preference in Drosophila melanogaster
- 2008
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In: Current Biology. - : Elsevier BV. - 1879-0445 .- 0960-9822. ; 18, s. 1438-1443
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Journal article (peer-reviewed)abstract
- Chemosensory stimuli play a crucial role for host selection in insects, including the fruit fly Drosophila melanogaster[1]. Drosophila has been instrumental in unraveling the neurological basis of olfactory processing in insects [2]. Basic knowledge regarding chemical ecology and thorough studies of olfactory preferences are still lacking to a great extent in D. melanogaster, however. We have characterized repeatable variation in olfactory preference between five classical D. melanogaster wild-type strains toward a large array of natural host odors and synthetic compounds. By recording the rate of attraction over up to 24 hr, we could compare stimuli varying in attractiveness and characterize phenotypic parameters on the basis of individual stimuli and the whole stimulus array. Behavioral differences between strains were predominantly due to variation in a single phenotypic parameter: their overall responsiveness toward optimal and suboptimal olfactory stimuli. These differences were not explained by variation in olfactory sensitivity, locomotory activity, or general vigor monitored by survival. Comparisons with three recently established wild-type strains indicated that a high behavioral threshold against accepting suboptimal olfactory stimuli is the characteristic phenotype of wild D. melanogaster.
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| 48. |
- Rybak, Jürgen, et al.
(author)
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Synaptic circuitry of identified neurons in the antennal lobe of Drosophila melanogaster
- 2016
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In: Journal of Comparative Neurology. - : Wiley. - 0021-9967 .- 1096-9861. ; 524:9, s. 1920-1956
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Journal article (peer-reviewed)abstract
- In Drosophila melanogaster olfactory sensory neurons (OSNs) establish synapses with projection neurons (PNs) and local interneurons within antennal lobe (AL) glomeruli. Substantial knowledge regarding this circuitry has been obtained by functional studies, whereas ultrastructural evidence of synaptic contacts is scarce. To fill this gap, we studied serial sections of three glomeruli using electron microscopy. Ectopic expression of a membrane-bound peroxidase allowed us to map synaptic sites along PN dendrites. Our data prove for the first time that each of the three major types of AL neurons is both pre- and postsynaptic to the other two types, as previously indicated by functional studies. PN dendrites carry a large proportion of output synapses, with approximately one output per every three input synapses. Detailed reconstructions of PN dendrites showed that these synapses are distributed unevenly, with input and output sites partially segregated along a proximal-distal gradient and the thinnest branches carrying solely input synapses. Moreover, our data indicate synapse clustering, as we found evidence of dendritic tiling of PN dendrites. PN output synapses exhibited T-shaped presynaptic densities, mostly arranged as tetrads. In contrast, output synapses from putative OSNs showed elongated presynaptic densities in which the T-bar platform was supported by several pedestals and contacted as many as 20 postsynaptic profiles. We also discovered synaptic contacts between the putative OSNs. The average synaptic density in the glomerular neuropil was about two synapses/mu m(3). These results are discussed with regard to current models of olfactory glomerular microcircuits across species. J. Comp. Neurol. 524:1920-1956, 2016.
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| 49. |
- Sadek, Medhat M., et al.
(author)
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Glomerular representation of plant volatiles and sex pheromone components in the antennal lobe of the female Spodoptera littoralis.
- 2002
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In: Journal of Experimental Biology. - 1477-9145. ; 205:10, s. 1363-1376
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Journal article (peer-reviewed)abstract
- We studied the projection patterns of antennal lobe (AL) interneurones sensitive to plant volatiles and female-produced sex pheromone components in the female moth, Spodoptera littoralis. Ten compounds (eight plant-derived compounds and two sex pheromone components) were singly applied to the antenna and, using intracellular recording and staining techniques, the physiological and morphological characteristics of responding neurones were investigated. In addition, ALs stained with a synapsin antibody were optically sectioned using confocal microscopy, and a three-dimensional map of glomeruli in the anterior aspect of the AL was reconstructed. We used the map as a reference for identification of glomeruli innervated by projection neurones (PNs) that respond to plant volatiles and/or pheromone components. Nineteen PNs, responding to one to seven compounds of the ten tested stimuli, were stained with neurobiotin. These neurones each arborised in a single glomerulus in the frontal side of the AL. PNs responding to the same compound arborised in different glomeruli and PNs arborising in the same glomerulus responded to different compounds. Accordingly, glomeruli harbouring the dendritic arborisations of PNs responding to each of the tested compounds constituted a unique array of glomeruli that were not necessarily adjacent. It was thus clear that, at the output level, a single plant volatile or a sex pheromone component was not represented within a single glomerulus in the AL. We expect complex patterns of glomeruli to be involved in the coding of plant-derived compounds, as well as sex pheromone components, in female S. littoralis.
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| 50. |
- Schiestl, F. P., et al.
(author)
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Orchid pollination by sexual swindle [5]
- 1999
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 399:6735, s. 421-422
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Journal article (peer-reviewed)
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