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Insect Science Oct 2023The complex and efficient sex pheromone communication system in insects is essential for reproduction and for reproductive isolation of species. In moths, sex pheromone...
The complex and efficient sex pheromone communication system in insects is essential for reproduction and for reproductive isolation of species. In moths, sex pheromone communication starts with male attraction to compounds emitted by females; only a few species act in the reverse. However, how the pheromones that are emitted by both sexes co-regulate and coordinate mate finding and mating remains unknown. Here, we identified both the male and female pheromones of Eastern Grass Veneer moth, Agriphila aeneociliella (Lepidoptera: Crambidae), and demonstrated their efficiency in manipulating behavioral responses of the opposite sex. Combining data from analysis of gas chromatography-electroantennogram detection, gas chromatography-mass spectrometry, and olfactory behavior assays, the female pheromone of A. aeneociliella was identified as (Z,Z,Z)-9,12,15-octadecatrienal and (Z)-9-hexadecenyl acetate, while the male pheromone was determined to be 1-nonanal. Both the 2 individual components of the female pheromone and their binary mixture were significantly attractive to males, and the 1-nonanal male pheromone induced strong electrophysiological responses in females and induced attraction of females in a Y-tube olfactory test. Depending on the concentration of 1-nonanal, its addition to the binary mixture of the female pheromone either enhanced (10 or 10 μg/μL) or reduced (1 μg/μL) the aphrodisiac effect of the mixture on males. In wind-tunnel bioassays, different concentrations of pheromones, including the binary mixture of female pheromone and the mixture of male and female pheromones, had significant effects on male behavior. Our findings suggested that the blend of both female and male pheromones plays a significant role in the sexual communication system in some moths.
PubMed: 36606503
DOI: 10.1111/1744-7917.13171 -
Antibiotics (Basel, Switzerland) Nov 2023A total of seventy VanA-type vancomycin-resistant enterococci (VRE) isolates obtained in Taiwan in the early 2000s were retrospectively characterized. Forty isolates...
A total of seventy VanA-type vancomycin-resistant enterococci (VRE) isolates obtained in Taiwan in the early 2000s were retrospectively characterized. Forty isolates were obtained from human patients and thirty from livestock. Of these VRE isolates, twenty-three (57.5%) of the human VRE and thirty (100%) of the livestock VRE were , and the remaining seventeen (42.5%) of the human VRE were . Of the 53 isolates, twenty-two (96%) of the human VRE and thirty (100%) of the livestock VRE exhibited a high level of resistance to vancomycin and sensitivity to teicoplanin. They also had three amino acid substitutions in the N-terminal region of the deduced VanS sequence. The vancomycin resistance of all of the 22 human isolates, and 20 of the 30 livestock isolates, transferred to FA2-2 at a frequency of 10 to 10 per donor cell in broth. Each of the transconjugants responded to pheromone (i.e., FA2-2 culture filtrate), indicating that the conjugative plasmids were pheromone-responsive plasmids. Three of the conjugative plasmids originated from human isolates, and five plasmids from livestock isolates were corresponded and classified as type A plasmid. Two plasmids originated from human isolates and six plasmids from livestock isolates were corresponded and classified as type B plasmid. FA2-2 containing either the type A or type B plasmid responded to the synthetic pheromone cAD1. The type A and type B plasmids transferred between FA2-2 and JH2SS at a frequency of about 10 per donor cell and conferred vancomycin, bacitracin, and erythromycin resistances. The complete DNA sequence of the representative type A plasmid pTW9 (85,068 bp) showed that the plasmid carried a Tn-like element encoding -type resistance, erythromycin resistance (), and bacitracin resistance (). The plasmid contained the regulatory region found in the pheromone-responsive plasmid and encoded the genes , and , which are the key negative regulatory elements, and , a key positive regulator of plasmid pAD1, indicating that plasmid pTW9 was pAD1-type pheromone-responsive plasmid. PFGE analysis of SmaI-digested chromosomal DNAs showed that several strains harboring an identical type A pheromone-responsive plasmid were indistinguishable, and that these were identified both in human and livestock isolates, indicating the transmissions of the VRE strains between livestock and humans. These data showed that the multiple-drug-resistant pheromone-responsive conjugative plasmids have been widely spread in both human and livestock VRE, and there was high potential for transfers of VRE from food animals to humans in Taiwan in the early 2000s.
PubMed: 38136702
DOI: 10.3390/antibiotics12121668 -
International Journal of Molecular... May 2024The effect of pesticides on insects is often discussed in terms of acute and chronic toxicity, but an important and often overlooked aspect is the impact of sublethal... (Review)
Review
The effect of pesticides on insects is often discussed in terms of acute and chronic toxicity, but an important and often overlooked aspect is the impact of sublethal doses on insect physiology and behavior. Pesticides can influence various physiological parameters of insects, including the innate immune system, development, and reproduction, through a combination of direct effects on specific exposed tissues and the modification of behaviors that contribute to health and reproductive success. Such behaviors include mobility, feeding, oviposition, navigation, and the ability to detect pheromones. Pesticides also have a profound effect on insect learning and memory. The precise effects depend on many different factors, including the insect species, age, sex, caste, physiological condition, as well as the type and concentration of the active ingredients and the exposure route. More studies are needed to assess the effects of different active ingredients (and combinations thereof) on a wider range of species to understand how sublethal doses of pesticides can contribute to insect decline. This review reflects our current knowledge about sublethal effects of pesticides on insects and advancements in the development of innovative methods to detect them.
Topics: Animals; Insecta; Pesticides; Reproduction; Behavior, Animal
PubMed: 38892195
DOI: 10.3390/ijms25116007 -
Annual Review of Entomology Jan 2024Palm weevils, spp., are destructive pests of native, ornamental, and agricultural palm species. Of the 10 recognized species, two of the most injurious species, and ,... (Review)
Review
Palm weevils, spp., are destructive pests of native, ornamental, and agricultural palm species. Of the 10 recognized species, two of the most injurious species, and , both of which have spread beyond their native range, are the best studied. Due to its greater global spread and damage to edible date industries in the Middle East, has received more research interest. Integrated pest management programs utilize traps baited with aggregation pheromone, removal of infested palms, and insecticides. However, weevil control is costly, development of resistance to insecticides is problematic, and program efficacy can be impaired because early detection of infestations is difficult. The genome of has been sequenced, and omics research is providing insight into pheromone communication and changes in volatile and metabolism profiles of weevil-infested palms. We outline how such developments could lead to new control strategies and early detection tools.
Topics: Animals; Weevils; Coleoptera; Insecticides; Arecaceae; Pheromones; Biology
PubMed: 38270987
DOI: 10.1146/annurev-ento-013023-121139 -
Animals : An Open Access Journal From... Nov 2023Noise fears represent the most common behavioural problem in dogs. This manuscript provides an overview of diverse approaches for alleviating fear of noises in dogs and... (Review)
Review
Noise fears represent the most common behavioural problem in dogs. This manuscript provides an overview of diverse approaches for alleviating fear of noises in dogs and the supporting evidence. In the treatment of noise fears, both short-term solutions to prevent trauma or the deterioration of fear during unavoidable noise events and longer-term training need to be considered. Environmental management, the provision of incentives (food/play) during noise exposure, and, when indicated, anxiolytic medication, can safeguard dogs' welfare during noise events. Most "alternative" products (such as nutraceuticals, herbal remedies, pheromones, homeopathy, Bach flowers, and essential oils) are unlikely to be sufficient as monotherapy for noise fears, whereas there is good evidence for the efficacy of several anxiolytic medications. In the longer term, counterconditioning to real-life noises, relaxation training, and desensitisation/counterconditioning using noise recordings have been shown to improve fear of noises in dogs. Preventative training appears to be highly effective in preventing the development of noise fears in puppies and adult dogs.
PubMed: 38067015
DOI: 10.3390/ani13233664 -
The Journal of Veterinary Medical... May 2024Little is known about the neuronal structure of the vomeronasal organ (VNO), a receptor organ responsible for pheromone perception, in the alpaca (Vicugna pacos). This...
Little is known about the neuronal structure of the vomeronasal organ (VNO), a receptor organ responsible for pheromone perception, in the alpaca (Vicugna pacos). This study was performed to determine the localization of neuronal elements, including protein gene product 9.5 (PGP 9.5), a pan-neuronal marker, olfactory marker protein (OMP), a marker of mature olfactory receptor cells, and phospholipase C beta 2 (PLC-β2), a marker of solitary chemoreceptor cells (SCCs), in the VNO. OMP was identified in receptor cells of the vomeronasal sensory epithelium (VSE), while PGP 9.5 and PLC-β2 were localized in both the VSE and vomeronasal non-sensory epithelium. Collectively, these results suggested that the alpaca VNO possesses SCCs and olfactory receptor cells, which recognize both harmful substances and pheromones.
Topics: Animals; Vomeronasal Organ; Camelids, New World; Male; Olfactory Marker Protein; Phospholipase C beta; Female; Olfactory Receptor Neurons; Chemoreceptor Cells; Ubiquitin Thiolesterase
PubMed: 38508726
DOI: 10.1292/jvms.23-0430 -
Insect Biochemistry and Molecular... Nov 2023Olfactory perception of pheromones in insects involves odorant-binding proteins (OBPs), relatively small proteins (ca.110-240 amino acid residues) that can bind...
Olfactory perception of pheromones in insects involves odorant-binding proteins (OBPs), relatively small proteins (ca.110-240 amino acid residues) that can bind reversibly to behaviourally active olfactory ligands. In this study, we investigated the binding in silico and in vitro of the aphid sex pheromone components (1R,4aS,7S,7aR)-nepetalactol and (4aS,7S,7aR)-nepetalactone and the aphid alarm pheromone (E)-β-farnesene by OBPs from the pea aphid, Acyrthosiphon pisum. Screening of protein models of ApisOBPs1-11 with the aphid sex pheromone components suggested that ApisOPB6 was a candidate. Fluorescence assays using ApisOBP6 suggested that ApisOBP6 was able to bind both sex pheromone components and discriminate from the aphid alarm pheromone and the generic plant compound (R/S)-linalool. Saturation transfer difference NMR experiments with ApisOBP6 yielded results consistent to those from the fluorescence experiments, with a clear interaction between ApisOBP6 and (4aS,7S,7aR)-nepetalactone. These results describe a novel interaction and potential function for ApisOBP6, point to pre-receptor odorant discrimination by OBPs, and provide a platform for investigating the function of other aphid olfactory proteins involved in aphid chemical ecology.
Topics: Animals; Pheromones; Sex Attractants; Aphids; Pisum sativum
PubMed: 37827436
DOI: 10.1016/j.ibmb.2023.104026 -
Scientific Reports Oct 2023Targeted metabolomics has been widely used in pheromone research but may miss pheromone components in study organisms that produce pheromones in trace amount and/or lack...
Targeted metabolomics has been widely used in pheromone research but may miss pheromone components in study organisms that produce pheromones in trace amount and/or lack bio-detectors (e.g., antennae) to readily locate them in complex samples. Here, we used non-targeted metabolomics-together with high-performance liquid chromatography-mass spectrometry (HPLC-MS), gas chromatography-MS, and behavioral bioassays-to unravel the sex pheromone of the triangulate cobweb spider, Steatoda triangulosa. A ternary blend of three contact pheromone components [N-4-methylvaleroyl-O-isobutyroyl-L-serine (5), N-3-methylbutyryl-O-isobutyroyl-L-serine (11), and N-3-methylbutyryl-O-butyroyl-L-serine (12)] elicited courtship by S. triangulosa males as effectively as female web extract. Hydrolysis of 5, 11 and 12 at the ester bond gave rise to two mate-attractant pheromone components [butyric acid (7) and isobutyric acid (8)] which attracted S. triangulosa males as effectively as female webs. Pheromone components 11 and 12 are reported in spiders for the first time, and were discovered only through the use of non-targeted metabolomics and GC-MS. All compounds resemble pheromone components previously identified in widow spiders. Our study provides impetus to apply non-targeted metabolomics for pheromone research in a wide range of animal taxa.
Topics: Male; Animals; Female; Sex Attractants; Spiders; Sexual Behavior, Animal; Pheromones; Hydrolases; Serine
PubMed: 37891331
DOI: 10.1038/s41598-023-44948-0 -
Annual Review of Entomology Jan 2024vegetable and oilseed crops are attacked by several different flea beetle species (Chrysomelidae: Alticini). Over the past decades, most research has focused on two... (Review)
Review
vegetable and oilseed crops are attacked by several different flea beetle species (Chrysomelidae: Alticini). Over the past decades, most research has focused on two species, and , which are major pests of oilseed rape in North America. More recently, and especially after the ban of neonicotinoids in the European Union, the cabbage stem flea beetle, , has become greatly important and is now considered to be the major pest of winter oilseed rape in Europe. The major challenges to flea beetle control are the prediction of population dynamics in the field, differential susceptibility to insecticides, and the lack of resistant plant cultivars and other economically viable alternative management strategies. At the same time, many fundamental aspects of flea beetle biology and ecology, which may be relevant for the development of sustainable control strategies, are not well understood. This review focuses on the interactions between flea beetles and plants and summarizes the literature on current management strategies with an emphasis on the potential for biological control in flea beetle management.
Topics: Animals; Brassica; Coleoptera; Siphonaptera; Insecticides; Brassica napus; Ecology
PubMed: 38270984
DOI: 10.1146/annurev-ento-033023-015753 -
Royal Society Open Science Dec 2023The transition from terrestrial to aquatic life by hydrophiine elapid snakes modified targets of natural selection and likely affected sexual selection also. Thus, the...
The transition from terrestrial to aquatic life by hydrophiine elapid snakes modified targets of natural selection and likely affected sexual selection also. Thus, the shift to marine life also might have affected sexual dimorphism. Our measurements of 419 preserved specimens of six species of aipysurine snakes (genera and ) revealed sexual dimorphism in mean adult snout-vent length (SVL), body width relative to SVL, lengths and widths of heads and tails relative to SVL, and eye diameter relative to head length. Females averaged larger than males in all taxa, and generally were wider-bodied with shorter and wider tails and smaller eyes. For other traits, sexual dimorphism varied among species: for example, relative head length ranged from male-biased to female-biased, and head shape (width relative to length) was highly dimorphic only in . The transition to marine life may have eliminated male-male combat (reducing selection for large males) and favoured visual rather than pheromone-based mate-searching (favouring larger eyes in males). Variation in head-size dimorphism may reflect intersexual niche partitioning, with different taxa following different trajectories. Repeated evolutionary transitions from terrestrial to aquatic life in snakes provide a powerful opportunity to explore selective forces on sexually dimorphic traits.
PubMed: 38094274
DOI: 10.1098/rsos.231261