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1.
Front Neural Circuits ; 18: 1409994, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38742089

RESUMO

Pheromones are specialized chemical messengers used for inter-individual communication within the same species, playing crucial roles in modulating behaviors and physiological states. The detection mechanisms of these signals at the peripheral organ and their transduction to the brain have been unclear. However, recent identification of pheromone molecules, their corresponding receptors, and advancements in neuroscientific technology have started to elucidate these processes. In mammals, the detection and interpretation of pheromone signals are primarily attributed to the vomeronasal system, which is a specialized olfactory apparatus predominantly dedicated to decoding socio-chemical cues. In this mini-review, we aim to delineate the vomeronasal signal transduction pathway initiated by specific vomeronasal receptor-ligand interactions in mice. First, we catalog the previously identified pheromone ligands and their corresponding receptor pairs, providing a foundational understanding of the specificity inherent in pheromonal communication. Subsequently, we examine the neural circuits involved in processing each pheromone signal. We focus on the anatomical pathways, the sexually dimorphic and physiological state-dependent aspects of signal transduction, and the neural coding strategies underlying behavioral responses to pheromonal cues. These insights provide further critical questions regarding the development of innate circuit formation and plasticity within these circuits.


Assuntos
Feromônios , Transdução de Sinais , Órgão Vomeronasal , Animais , Feromônios/fisiologia , Camundongos , Transdução de Sinais/fisiologia , Órgão Vomeronasal/fisiologia
2.
Elife ; 122024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747258

RESUMO

In most mammals, conspecific chemosensory communication relies on semiochemical release within complex bodily secretions and subsequent stimulus detection by the vomeronasal organ (VNO). Urine, a rich source of ethologically relevant chemosignals, conveys detailed information about sex, social hierarchy, health, and reproductive state, which becomes accessible to a conspecific via vomeronasal sampling. So far, however, numerous aspects of social chemosignaling along the vomeronasal pathway remain unclear. Moreover, since virtually all research on vomeronasal physiology is based on secretions derived from inbred laboratory mice, it remains uncertain whether such stimuli provide a true representation of potentially more relevant cues found in the wild. Here, we combine a robust low-noise VNO activity assay with comparative molecular profiling of sex- and strain-specific mouse urine samples from two inbred laboratory strains as well as from wild mice. With comprehensive molecular portraits of these secretions, VNO activity analysis now enables us to (i) assess whether and, if so, how much sex/strain-selective 'raw' chemical information in urine is accessible via vomeronasal sampling; (ii) identify which chemicals exhibit sufficient discriminatory power to signal an animal's sex, strain, or both; (iii) determine the extent to which wild mouse secretions are unique; and (iv) analyze whether vomeronasal response profiles differ between strains. We report both sex- and, in particular, strain-selective VNO representations of chemical information. Within the urinary 'secretome', both volatile compounds and proteins exhibit sufficient discriminative power to provide sex- and strain-specific molecular fingerprints. While total protein amount is substantially enriched in male urine, females secrete a larger variety at overall comparatively low concentrations. Surprisingly, the molecular spectrum of wild mouse urine does not dramatically exceed that of inbred strains. Finally, vomeronasal response profiles differ between C57BL/6 and BALB/c animals, with particularly disparate representations of female semiochemicals.


Assuntos
Órgão Vomeronasal , Animais , Órgão Vomeronasal/fisiologia , Camundongos , Masculino , Feminino , Odorantes/análise , Feromônios/urina , Feromônios/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos
3.
Genesis ; 62(3): e23603, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38738564

RESUMO

The vomeronasal organ (VNO) is a specialized chemoreceptive structure in many vertebrates that detects chemical stimuli, mostly pheromones, which often elicit innate behaviors such as mating and aggression. Previous studies in rodents have demonstrated that chemical stimuli are actively transported to the VNO via a blood vessel-based pumping mechanism, and this pumping mechanism is necessary for vomeronasal stimulation in behaving animals. However, the molecular mechanisms that regulate the vomeronasal pump remain mostly unknown. In this study, we observed a high level of expression of phosphodiesterase 5A (PDE5A) in the vomeronasal blood vessel of mice. We provided evidence to support the potential role of PDE5A in vomeronasal pump regulation. Local application of PDE5A inhibitors-sildenafil or tadalafil-to the vomeronasal organ (VNO) reduced stimulus delivery into the VNO, decreased the pheromone-induced activity of vomeronasal sensory neurons, and attenuated male-male aggressive behaviors. PDE5A is well known to play a role in regulating blood vessel tone in several organs. Our study advances our understanding of the molecular regulation of the vomeronasal pump.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 5 , Órgão Vomeronasal , Animais , Órgão Vomeronasal/metabolismo , Camundongos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/genética , Masculino , Inibidores da Fosfodiesterase 5/farmacologia , Tadalafila/farmacologia , Citrato de Sildenafila/farmacologia , Feromônios/metabolismo , Agressão/fisiologia , Feminino , Camundongos Endogâmicos C57BL
4.
BMC Biol ; 22(1): 108, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714997

RESUMO

BACKGROUND: Populations of the plant pathogenic fungus Verticillium dahliae display a complex and rich genetic diversity, yet the existence of sexual reproduction in the fungus remains contested. As pivotal genes, MAT genes play a crucial role in regulating cell differentiation, morphological development, and mating of compatible cells. However, the functions of the two mating type genes in V. dahliae, VdMAT1-1-1, and VdMAT1-2-1, remain poorly understood. RESULTS: In this study, we confirmed that the MAT loci in V. dahliae are highly conserved, including both VdMAT1-1-1 and VdMAT1-2-1 which share high collinearity. The conserved core transcription factor encoded by the two MAT loci may facilitate the regulation of pheromone precursor and pheromone receptor genes by directly binding to their promoter regions. Additionally, peptide activity assays demonstrated that the signal peptide of the pheromone VdPpg1 possessed secretory activity, while VdPpg2, lacked a predicted signal peptide. Chemotactic growth assays revealed that V. dahliae senses and grows towards the pheromones FO-a and FO-α of Fusarium oxysporum, as well as towards VdPpg2 of V. dahliae, but not in response to VdPpg1. The findings herein also revealed that VdMAT1-1-1 and VdMAT1-2-1 regulate vegetative growth, carbon source utilization, and resistance to stressors in V. dahliae, while negatively regulating virulence. CONCLUSIONS: These findings underscore the potential roles of VdMAT1-1-1 and VdMAT1-2-1 in sexual reproduction and confirm their involvement in various asexual processes of V. dahliae, offering novel insights into the functions of mating type genes in this species.


Assuntos
Genes Fúngicos Tipo Acasalamento , Genes Fúngicos Tipo Acasalamento/genética , Ascomicetos/genética , Ascomicetos/fisiologia , Feromônios/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Verticillium
5.
J Insect Sci ; 24(2)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38597910

RESUMO

Larval habitats of blood-feeding stable flies, Stomoxys calcitrans (L.) (Diptera: Muscidae), overlap with foraging sites of black blow flies, Phormia regina (Meigen) (Diptera: Calliphoridae). We tested the hypothesis that bacteria in blow fly excreta inform oviposition decisions by female stable flies. In laboratory 2-choice bioassays, we offered gravid female stable flies fabric-covered agar plates as oviposition sites that were kept sterile or inoculated with either a blend of 7 bacterial strains isolated from blow fly excreta (7-isolate-blend) or individual bacterial isolates from that blend. The 7-isolate-blend deterred oviposition by female stable flies, as did either of 2 strains of Morganella morganii subsp. sibonii. Conversely, Exiguobacterium sp. and Serratia marcescens each prompted oviposition by flies. The flies' oviposition decisions appear to be guided by bacteria-derived semiochemicals as the bacteria could not be physically accessed. Oviposition deterrence caused by semiochemicals of the 7-isolate-blend may help stable flies avoid competition with blow flies. The semiochemicals of bioactive bacterial strains could be developed as trap lures to attract and capture flies and deter their oviposition in select larval habitats.


Assuntos
Morganella , Muscidae , Feminino , Animais , Calliphoridae , Oviposição , Larva , Bactérias , Feromônios
6.
Sci Rep ; 14(1): 7883, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570567

RESUMO

In this work, we identified the trail pheromone of the ant Crematogaster scutellaris. We combined gas chromatography-mass spectrometry analysis of extracts from the hind tibia, the location of the respective glands, with automated trail following assays. The study found tridecan-2-ol to be the strongest discriminator between hind tibia and other body part extracts. Tridecan-2-ol elicited trail-following behaviour at concentrations of 1 ng/µL. A separation of the enantiomers showed responses to (R)-tridecan-2-ol already at 0.001 ng/µL and only at a 1000-fold higher concentration for (S)-tridecan-2-ol, suggesting that only the R enantiomer is used by C. scutellaris in its natural environment. We also found strong behavioural responses to 2-dodecanol, a substance that was not detectable in the hind tibia extract of C. scutellaris, but which has been reported to be the trail pheromone of the related species C. castanea. We discuss the contribution of these results to the 'dissection and reconstruction' of strategies and mechanisms underlying the social organization of ants.


Assuntos
Formigas , Feromônios , Animais , Feromônios/análise , Formigas/fisiologia , Comportamento Animal , Comportamento Alimentar
7.
Sci Rep ; 14(1): 8555, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609415

RESUMO

Many gregarious insect species use aggregation and alarm pheromones. The bed bug, Cimex lectularius L., emits an alarm pheromone (AP), a 70/30 blend of (E)-2-hexenal and (E)-2-octenal, when threatened. Bed bugs avoid temperatures above 43 °C, which are lethal to bugs and used commercially as spatial heat treatments to manage infestations. However, the interaction of bed bug AP in heat avoidance has not been investigated. The goal of this research was to: 1) determine if bed bugs emit AP as an alarm response to heat exposure, and 2) quantify the behavioral responses of conspecifics to AP emitted by heat-exposed bed bugs. Using a selected ion flow tube mass spectrometer, we found that bed bugs responded to lethal and sublethal heat exposure by emitting AP. The Harlan laboratory population emitted more pheromone than a laboratory adapted field population from Florida (McCall). Harlan females emitted the most AP, followed by Harlan males, McCall females and males. In separate behavioral experiments, we showed that conspecifics (i.e., recipients) reacted to AP released by heat exposed bed bugs (i.e., emitters) by frantically moving within 50 mm and 100 mm test arenas. The Harlan recipients reacted to AP in 100 mm areas, whereas the McCall strain did not, indicating a short area of effectiveness of the AP. Synthetic AP components tested in behavioral experiments caused identical effects as the natural AP blend released by heat-exposed bed bugs.


Assuntos
Aldeídos , Percevejos-de-Cama , Ectoparasitoses , Feminino , Masculino , Animais , Temperatura Alta , Causalidade , Feromônios
8.
Nat Commun ; 15(1): 2872, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605003

RESUMO

Animals employ different strategies to establish mating boundaries between closely related species, with sex pheromones often playing a crucial role in identifying conspecific mates. Many of these pheromones have carbon-carbon double bonds, making them vulnerable to oxidation by certain atmospheric oxidant pollutants, including ozone. Here, we investigate whether increased ozone compromises species boundaries in drosophilid flies. We show that short-term exposure to increased levels of ozone degrades pheromones of Drosophila melanogaster, D. simulans, D. mauritiana, as well as D. sechellia, and induces hybridization between some of these species. As many of the resulting hybrids are sterile, this could result in local population declines. However, hybridization between D. simulans and D. mauritiana as well as D. simulans and D. sechellia results in fertile hybrids, of which some female hybrids are even more attractive to the males of the parental species. Our experimental findings indicate that ozone pollution could potentially induce breakdown of species boundaries in insects.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Masculino , Feminino , Drosophila melanogaster/genética , Reprodução , Drosophila simulans , Carbono , Feromônios
9.
Mol Biol Cell ; 35(6): ar85, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656798

RESUMO

In response to pheromone Saccharomyces cerevisiae extend a mating projection. This process depends on the formation of polarized actin cables which direct secretion to the mating tip and translocate the nucleus for karyogamy. Here, we demonstrate that proper mating projection formation requires the formin Bni1, as well as the actin nucleation promoting activities of Bud6, but not the formin Bnr1. Further, Bni1 is required for pheromone gradient tracking. Our work also reveals unexpected new functions for Bil2 in the pheromone response. Previously we identified Bil2 as a direct inhibitor of Bnr1 during vegetative cell growth. Here, we show that Bil2 has Bnr1-independent functions in spatially focusing Bni1-GFP at mating projection tips, and in vitro Bil2 and its binding partner Bud6 organize Bni1 into clusters that nucleate actin assembly. bil2∆ cells also display entangled Bni1-generated actin cable arrays and defects in secretory vesicle transport and nuclear positioning. At low pheromone concentrations, bil2∆ cells are delayed in establishing a polarity axis, and at high concentrations they prematurely form a second and a third mating projection. Together, these results suggest that Bil2 promotes the proper formation and timing of mating projections by organizing Bni1 and maintaining a persistent axis of polarized growth.


Assuntos
Actinas , Feromônios , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Feromônios/metabolismo , Actinas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/genética , Polaridade Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo
10.
Pestic Biochem Physiol ; 201: 105874, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685243

RESUMO

In insects, chemosensory proteins (CSPs) play an important role in the perception of the external environment and have been widely used for protein-binding characterization. Riptortus pedestris has received increased attention as a potential cause of soybean staygreen syndrome in recent years. In this study, we found that RpedCSP4 expression in the antennae of adult R. pedestris increased with age, with no significant difference in expression level observed between males and females, as determined through quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, we investigated the ability of RpedCSP4 to bind various ligands (five aggregated pheromone components and 13 soybean volatiles) using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP4 binds to three aggregated pheromone components of R. pedestris, namely, ((E)-2-hexenyl (Z)-3-hexenoate (E2Z3), (E)-2-hexenyl (E)-2-hexenoate (E2E2), and (E)-2-hexenyl hexenoate (E2HH)), and that its binding capacities are most stable under acidic condition. Finally, the structure and protein-ligand interactions of RpedCSP4 were further analyzed via homology modeling, molecular docking, and targeted mutagenesis experiments. The L29A mutant exhibited a loss of binding ability to these three aggregated pheromone components. Our results show that the olfactory function of RpedCSP4 provides new insights into the binding mechanism of RpedCSPs to aggregation pheromones and contributes to discover new target candidates that will provide a theoretical basis for future population control of R. pedestris.


Assuntos
Proteínas de Insetos , Feromônios , Animais , Feromônios/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/química , Masculino , Feminino , Ligação Proteica , Heterópteros/metabolismo , Heterópteros/genética
11.
Chemosphere ; 357: 141953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614395

RESUMO

The effects of culture filtrate of Alexandrium tamarense on Prorocentrum donghaiense and Heterosigma akashiwo were investigated, including determination of algal density, photosynthesis, intracellular enzyme content and activity. The filtrate of A. tamarense had a stronger inhibitory effect on P. donghaiense than H. akashiwo, and the inhibitory effect decreased with higher temperature treatment of the filtrate. Instantaneous fluorescence (Ft) and maximum quantum yield of photosystem II (Fv/Fm) values of both kinds of target algae were reduced as exposed to the filtrate of A. tamarense, which proved that allelopathy could inhibit the normal operation of photosynthetic system. The increase of Malondialdehyde (MDA) content of the two kinds of target algae indicated that the cell membrane was seriously damaged by allelochemicals released by A. tamarense. The different responses of Superoxide Dismutase (SOD) and Catalase (CAT) activity in two kinds of target algae demonstrated the complexity and diversity of allelopathic mechanism. The filtrate of A. tamarense also influenced the metabolic function (ATPases) of P. donghaiense and H. akashiwo, and the influence on P. donghaiense was greater. Liquid-liquid extraction was used to extract and isolate allelochemicals from the filtrate of A. tamarense. It was found that only component I with molecular weight of 424.2573 and 434.2857 could inhibit the growth of P. donghaiense by HPLC-MS.


Assuntos
Alelopatia , Catalase , Dinoflagellida , Malondialdeído , Feromônios , Fotossíntese , Dinoflagellida/fisiologia , Feromônios/farmacologia , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
12.
Plant Signal Behav ; 19(1): 2335025, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38678583

RESUMO

Allelopathy is the main chemical means in the invasion process of exotic plants and one of the key factors in grassland degradation. In this experiment, we investigated the effects of ethyl acetate phase extract (EAE), n-butanol phase extract (BE) and aqueous phase extract (AE) from the aboveground (stems and leaves) and roots of Ligularia sagitta on seed germination and seedling growth of four Gramineae forages (Poa pratensis L. Festuca ovina L. Elymus nutans Griseb. Agropyron cristatum (L.) Gaertn.) in their sympatric domains and one Legosuminae forage (Medicago sativa L.). The chemical components in each phase extract of L. sagitta were determined with UHPLC-MS/MS non-targeted metabolomics, and the differential compounds were screened using Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA). Within a set concentration range, EAE significantly inhibited seed germination and seedling growth of four Gramineae forages. BE and AE acted mainly in the seedling growth stage and did not significantly inhibit forage seed germination. P. pratensis was most sensitive to L. sagitta extracts; at 2.0 mg/mL of EAE from roots, germination energy and germination rate of P. pratensis seeds were 0. L. sagitta extracts inhibited the growth of M. sativa seedlings and did not inhibit its seed germination. A total of 904 compounds were identified with UHPLC-MS/MS, among which 31, 64, 81 and 66 metabolites displayed different accumulation patterns in the four comparison groups (R.EAE vs. R.BE, R.EAE vs. R.AE, SL.EAE vs. SL.BE, SL.EAE vs. SL.AE), respectively. In particular, 9 compounds were found to be common up-regulated differential metabolites in the four comparison groups and were enriched in EAE. Additionally, N,N-dimethylaniline, Caffeic acid, 4-Hydroxybenzoic acid, 4-Hydroxybenzaldehyde and cis-9-Octadecenoic acid as potential allelochemicals in L. sagitta. The results of this study support efforts at finding alternative control plants for the restoration of poisonous grass-type degraded grasslands.


Assuntos
Alelopatia , Asteraceae , Germinação , Espécies Introduzidas , Feromônios , Asteraceae/metabolismo , Asteraceae/efeitos dos fármacos , Feromônios/farmacologia , Feromônios/metabolismo , Germinação/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/crescimento & desenvolvimento , Extratos Vegetais/farmacologia
13.
Behav Processes ; 217: 105027, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38615896

RESUMO

The primary goal of the binary model in this study was to understand the convergence pattern of the Pheidole latinoda ants. Forager and scout ants on the hunt for food use path integration. When they find a food source, they leave a trail pheromone to alert other nest mates. Every ant starts following that trail and reinforces it on their way back home. To investigate the ant convergence pattern, binary and ternary bridges of varying lengths are used. Each bridge is built in such a way that one end is connected to a food source whilst the other end is connected to the nest. The food source is surrounded by water-filled islands. The Pheidole latinoda ant's convergence pattern has been observed following the successful installation of a bridge near the ants' nest. This species took between 1 and 3 and 3-4 min to find the shortest possible path. Numerous studies looking for optimal solutions, such as those addressing the challenges of travelling salesmen, routing in communication networks, etc., may use this convergence or path optimization as their new starting point.


Assuntos
Formigas , Comportamento Alimentar , Animais , Formigas/fisiologia , Heurística , Feromônios
14.
Sci Rep ; 14(1): 6037, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472207

RESUMO

The iconic European stag beetle (Lucanus cervus) (Coleoptera: Lucanidae) is one of the largest terrestrial beetles in Europe. Due to decreasing population numbers, thought to be a consequence of habitat loss, this beetle has become a near-threatened species across much of Europe, and a reliable monitoring system is required to measure its future population trends. As part of a programme aimed at conserving UK populations, we have investigated the chemical ecology of the beetle, with a view to developing an efficient semiochemical-based monitoring system. Such a scheme will be beneficial not only in the UK but across the European range of the species, where the beetle is of conservation concern. Here, we report on a surprising discovery of a male-produced pheromone, which provokes initial sexual receptivity in females, and which has not been previously identified in the animal kingdom. Furthermore, we assign sex pheromone function to a previously described female-specific compound.


Assuntos
Besouros , Atrativos Sexuais , Animais , Masculino , Feminino , Feromônios , Ecossistema , Espécies em Perigo de Extinção
15.
Int J Mol Sci ; 25(5)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38474187

RESUMO

Pheromone-binding proteins (PBPs) are specific odorant-binding proteins that can specifically recognize insect pheromones. Through transcriptional analysis of the antennae of adult Endoclita signifer, EsigPBP3 was discovered and identified, and EsigPBP3 was found to be highly expressed in the antennae of male moths. Based on the binding characteristics and ability of EsigPBP3, we can find the key ligands and binding site to consider as a target to control the key wood bore E. signifier. In this study, the fluorescence competitive binding assays (FCBA) showed that EsigPBP3 had a high binding affinity for seven key eucalyptus volatiles. Molecular docking analysis revealed that EsigPBP3 had the strongest binding affinity for the sexual pheromone component, (3E,7E)-4,7,11-trimethyl-1,3,7,10-dodecatetraene. Furthermore, same as the result of FCBA, the EsigPBP3 exhibited high binding affinities to key eucalyptus volatiles, eucalyptol, α-terpinene, (E)-beta-ocimene, (-)-ß-pinene, and (-)-α-pinene, and PHE35, MET7, VAL10, PHE38, ILE52, and PHE118 are key sites. In summary, EsigPBP3 exhibits high binding affinity to male pheromones and key volatile compounds and the crucial binding sites PHE35, MET7, VAL10, PHE38, ILE52, and PHE118 can act as targets in the recognition of E. signifier pheromones.


Assuntos
Eucalyptus , Mariposas , Receptores Odorantes , Masculino , Animais , Feromônios/metabolismo , Proteínas de Transporte/metabolismo , Eucalyptus/metabolismo , Simulação de Acoplamento Molecular , Mariposas/metabolismo , Receptores Odorantes/metabolismo , Proteínas de Insetos/metabolismo
16.
Bioresour Technol ; 398: 130525, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437966

RESUMO

Secondary metabolites with bioactivity are allelochemicals. This study adopted direct contact (R0) and indirect contact (separated by 0.45 µm membrane, R1-A for algae, R1-S for sludge) to reveal the role of metabolites especially allelochemicals on interaction of bacteria and algae. Direct contact exhibited better nutrients removal than indirect contact, due to less antibacterial allelochemicals and oxidative stress. Bacterial signaling molecules were not detected. The major algae-derived allelochemicals were 13-Docosenamide, 9-Octadecenamide, n-Hexadecanoic acid, erucic acid, octadecanoic acid, ß-sitosterol, and E,E,Z-1,3,12-Nonadecatriene-5,14-diol. Furthermore, presence of 13-Docosenamide and 9-Octadecenamide was associated with succession of Flavobacterium and suppression of nitrifying bacteria (Nitrosomonas, Ellin6067, and Nitrospira). Direct contact stimulated denitrifying bacteria Saccharimonadales and algae Scenedesmus, whereas indirect contact is friendly to Dechloromonas, Competibacter, nitrifying bacteria, algae Desmodesmus and Dictyosphaerium. This study highlights the essentiality of cell contact of bacteria-algae in establishing synergy, as cell contact mitigates antagonistic effect induced by metabolites.


Assuntos
Feromônios , Scenedesmus , Feromônios/farmacologia , Bactérias , Plantas , Esgotos/microbiologia
17.
Curr Biol ; 34(7): 1414-1425.e5, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38479388

RESUMO

To extract any adaptive benefit, the circadian clock needs to be synchronized to the 24-h day-night cycles. We have investigated if it is a general property of the brain's circadian clock to recognize social interactions as external time givers. Sociosexual interactions with the opposite sex are universal, prevalent even in the lives of solitary animals. The solitary adult life of the Spodoptera littoralis moth is singularly dedicated to sex, offering an ideal context for exploring the impact of sociosexual cues on circadian timekeeping. We have identified specific olfactory cues responsible for social entrainment, revealing a surprisingly strong influence of pheromone-mediated remote sociosexual interactions on circadian rhythms. Males' free-running rhythms are induced and synchronized by the sex pheromone that the female releases in a rhythmic fashion, highlighting a hierarchical relation between the female and male circadian oscillators. Even a single pulse of the sex pheromone altered clock gene expression in the male brain, surpassing the effect of light on the clock. Our finding of a daytime-dependent, lasting impact of pheromone on male's courtship efficacy indicates that circadian timing in moths is a trait under sexual selection. We have identified specific components of the sex-pheromone blend that lack mate-attractive property but have powerful circadian effects, providing rationale for their continued retention by the female. We show that such volatiles, when shared across sympatric moth species, can trigger communal synchronization. Our results suggest that the sex pheromone released by female moths entrains males' behavioral activity rhythm to ensure synchronized timing of mating.


Assuntos
Mariposas , Atrativos Sexuais , Animais , Masculino , Feminino , Spodoptera , Feromônios/metabolismo , Atrativos Sexuais/metabolismo , Ritmo Circadiano/genética
18.
Arthropod Struct Dev ; 79: 101346, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38520874

RESUMO

The large abundance of termites is partially achieved by their defensive abilities. Stylotermitidae represented by a single extant genus, Stylotermes, is a member of a termite group Neoisoptera that encompasses 83% of termite species and 94% of termite genera and is characterized by the presence of the frontal gland. Within Neoisoptera, Stylotermitidae represents a species-poor sister lineage of all other groups. We studied the structure of the frontal, labral and labial glands in soldiers and workers of Stylotermes faveolus, and the composition of the frontal gland secretion in S. faveolus and Stylotermes halumicus. We show that the frontal gland is a small active secretory organ in soldiers and workers. It produces a cocktail of monoterpenes in soldiers, and some of these monoterpenes and unidentified proteins in workers. The labral and labial glands are developed similarly to other termite species and contribute to defensive activities (labral in both castes, labial in soldiers) or to the production of digestive enzymes (labial in workers). Our results support the importance of the frontal gland in the evolution of Neoisoptera. Toxic, irritating and detectable monoterpenes play defensive and pheromonal functions and are likely critical novelties contributing to the ecological success of these termites.


Assuntos
Baratas , Isópteros , Animais , Feromônios/metabolismo , Monoterpenos/metabolismo
19.
Molecules ; 29(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474545

RESUMO

Sol g 2 is the major protein in Solenopsis geminata fire ant venom. It shares the highest sequence identity with Sol i 2 (S. invicta) and shares high structural homology with LmaPBP (pheromone-binding protein (PBP) from the cockroach Leucophaea maderae). We examined the specific Sol g 2 protein ligands from fire ant venom. The results revealed that the protein naturally formed complexes with hydrocarbons, including decane, undecane, dodecane, and tridecane, in aqueous venom solutions. Decane showed the highest affinity binding (Kd) with the recombinant Sol g 2.1 protein (rSol g 2.1). Surprisingly, the mixture of alkanes exhibited a higher binding affinity with the rSol g 2.1 protein compared to a single one, which is related to molecular docking simulations, revealing allosteric binding sites in the Sol g 2.1 protein model. In the trail-following bioassay, we observed that a mixture of the protein sol g 2.1 and hydrocarbons elicited S. geminata worker ants to follow trails for a longer time and distance compared to a mixture containing only hydrocarbons. This suggests that Sol g 2.1 protein may delay the evaporation of the hydrocarbons. Interestingly, the piperidine alkaloids extracted have the highest attraction to the ants. Therefore, the mixture of hydrocarbons and piperidines had a synergistic effect on the trail-following of ants when both were added to the protein.


Assuntos
Venenos de Formiga , Formigas , Animais , Proteínas de Transporte/metabolismo , Formigas Lava-Pés , Feromônios/química , Ligantes , Simulação de Acoplamento Molecular , Formigas/química , Alcanos/metabolismo
20.
Nat Commun ; 15(1): 2715, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548742

RESUMO

Extracellular vesicles (EVs) are integral to numerous biological processes, yet it is unclear how environmental factors or interactions among individuals within a population affect EV-regulated systems. In Caenorhabditis elegans, the evolutionarily conserved large EVs, known as exophers, are part of a maternal somatic tissue resource management system. Consequently, the offspring of individuals exhibiting active exopher biogenesis (exophergenesis) develop faster. Our research focuses on unraveling the complex inter-tissue and social dynamics that govern exophergenesis. We found that ascr#10, the primary male pheromone, enhances exopher production in hermaphrodites, mediated by the G-protein-coupled receptor STR-173 in ASK sensory neurons. In contrast, pheromone produced by other hermaphrodites, ascr#3, diminishes exophergenesis within the population. This process is regulated via the neuropeptides FLP-8 and FLP-21, which originate from the URX and AQR/PQR/URX neurons, respectively. Our results reveal a regulatory network that controls the production of somatic EV by the nervous system in response to social signals.


Assuntos
Proteínas de Caenorhabditis elegans , Vesículas Extracelulares , Humanos , Animais , Masculino , Caenorhabditis elegans/genética , Feromônios , Proteínas de Caenorhabditis elegans/genética , Neurônios/fisiologia
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