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1.
Bioessays ; 45(1): e2200162, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36382549

RESUMO

With the potential to process the world's agricultural and food waste, provide sustainable fodder for livestock, aquaculture, and pet animals, as well as act as a source of novel biomolecules, the black soldier fly, Hermetia illucens, has been launched into the leading position within the insects as feed industry. Fulfilment of these goals, however, requires mass-rearing facilities to have a steady supply of neonate larvae, which in-turn requires an efficient mating process to yield fertile eggs; yet, little is known about adult reproductive behavior, nor what physiological factors lead to its emergence. Moreover, fertile egg production tends to be highly variable in colony. Therefore, this review brings together what is currently known of the organismal biology of H. illucens, compiling information on adult morphology, physiology, biogeography, genomics, and behavioral ecology. As a holistic synthesis, it highlights several directions of interest for research to follow.


Assuntos
Dípteros , Eliminação de Resíduos , Animais , Dípteros/fisiologia , Alimentos , Larva , Biologia
2.
Am Nat ; 204(1): 96-104, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857342

RESUMO

AbstractMany Neotropical beetles present coloration patterns mimicking red-eyed flies, which are presumably evasive mimicry models. However, the role of predators in selecting for evasive mimics in nature remains untested. In a field experiment, we used nontoxic plasticine replicas of a specialized fly-mimicking beetle species, which we placed on the host plants of the beetles. We show that replicas painted with reddish patches simulating the eyes of flesh flies experienced a much lower predation rate than control replicas. We found that beak marks were the most frequent signs of attack on plasticine replicas, underlining the potential selective pressure exerted by birds. Replicas that matched the size of the beetles suffered higher predation than smaller or larger replicas. The predation rate was also higher for beetle replicas exposed during the warm and wet season, when adult beetles occur. Our results support predator-mediated selection of mimic beetles, highlighting that reddish spots resembling flies' eyes comprise an important trait in reducing attack by avian predators.


Assuntos
Mimetismo Biológico , Besouros , Comportamento Predatório , Animais , Besouros/fisiologia , Aves/fisiologia , Dípteros/fisiologia , Pigmentação
3.
Development ; 148(18)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34351416

RESUMO

The coordination of cells or structures within the plane of a tissue is known as planar polarization. It is often governed by the asymmetric distribution of planar polarity proteins within cells. A number of quantitative methods have been developed to provide a readout of planar polarized protein distributions. However, previous planar polarity quantification methods can be affected by variation in cell geometry. Hence, we developed a novel planar polarity quantification method based on Principal Component Analysis (PCA) that is shape insensitive. Here, we compare this method with other state-of-the-art methods on simulated models and biological datasets. We found that the PCA method performs robustly in quantifying planar polarity independently of variation in cell geometry and other image conditions. We designed a user-friendly graphical user interface called QuantifyPolarity, equipped with three polarity methods for automated quantification of polarity. QuantifyPolarity also provides tools to quantify cell morphology and packing geometry, allowing the relationship of these characteristics to planar polarization to be investigated. This tool enables experimentalists with no prior computational expertise to perform high-throughput cell polarity and shape analysis automatically and efficiently.


Assuntos
Polaridade Celular/fisiologia , Análise de Componente Principal/métodos , Animais , Dípteros/fisiologia , Feminino , Ensaios de Triagem em Larga Escala/métodos , Masculino
4.
Development ; 148(18)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34463760

RESUMO

Size is a fundamental feature of living entities and is intimately tied to their function. Scaling laws, which can be traced to D'Arcy Thompson and Julian Huxley, have emerged as a powerful tool for studying regulation of the growth dynamics of organisms and their constituent parts. Yet, throughout the 20th century, as scaling laws were established for single cells, quantitative studies of the coordinated growth of multicellular structures have lagged, largely owing to technical challenges associated with imaging and image processing. Here, we present a supervised learning approach for quantifying the growth dynamics of germline cysts during oogenesis. Our analysis uncovers growth patterns induced by the groupwise developmental dynamics among connected cells, and differential growth rates of their organelles. We also identify inter-organelle volumetric scaling laws, finding that nurse cell growth is linear over several orders of magnitude. Our approach leverages the ever-increasing quantity and quality of imaging data, and is readily amenable for studies of collective cell growth in other developmental contexts, including early mammalian embryogenesis and germline development.


Assuntos
Proliferação de Células/fisiologia , Animais , Evolução Biológica , Biologia do Desenvolvimento/métodos , Dípteros/fisiologia , Células Germinativas/fisiologia , Oogênese/fisiologia , Organelas/fisiologia
5.
Plant Cell Environ ; 47(7): 2675-2692, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38600764

RESUMO

The restriction of plant-symbiont dinitrogen fixation by an insect semiochemical had not been previously described. Here we report on a glycosylated triketide δ-lactone from Nephrotoma cornicina crane flies, cornicinine, that causes chlorosis in the floating-fern symbioses from the genus Azolla. Only the glycosylated trans-A form of chemically synthesized cornicinine was active: 500 nM cornicinine in the growth medium turned all cyanobacterial filaments from Nostoc azollae inside the host leaf-cavities into akinetes typically secreting CTB-bacteriocins. Cornicinine further inhibited akinete germination in Azolla sporelings, precluding re-establishment of the symbiosis during sexual reproduction. It did not impact development of the plant Arabidopsis thaliana or several free-living cyanobacteria from the genera Anabaena or Nostoc but affected the fern host without cyanobiont. Fern-host mRNA sequencing from isolated leaf cavities confirmed high NH4-assimilation and proanthocyanidin biosynthesis in this trichome-rich tissue. After cornicinine treatment, it revealed activation of Cullin-RING ubiquitin-ligase-pathways, known to mediate metabolite signaling and plant elicitation consistent with the chlorosis phenotype, and increased JA-oxidase, sulfate transport and exosome formation. The work begins to uncover molecular mechanisms of cyanobiont differentiation in a seed-free plant symbiosis important for wetland ecology or circular crop-production today, that once caused massive CO2 draw-down during the Eocene geological past.


Assuntos
Gleiquênias , Lactonas , Simbiose , Animais , Lactonas/metabolismo , Gleiquênias/fisiologia , Gleiquênias/microbiologia , Gleiquênias/efeitos dos fármacos , Dípteros/fisiologia , Glicosilação , Cianobactérias/metabolismo , Cianobactérias/fisiologia , Cianobactérias/genética , Nostoc/fisiologia , Nostoc/genética , Nostoc/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia
6.
Insect Mol Biol ; 33(3): 206-217, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38180144

RESUMO

Parasitoids are important components of the natural enemy guild in the biological control of insect pests. They depend on host resources to complete the development of a specific stage or whole life cycle and thus have evolved towards optimal host exploitation strategies. In the present study, we report a specific survival strategy of a fly parasitoid Exorista sorbillans (Diptera: Tachinidae), which is a potential biological control agent for agricultural pests and a pest in sericulture. We found that the expression levels of nitric oxide synthase (NOS) and nitric oxide (NO) production in host Bombyx mori (Lepidoptera: Bombycidae) were increased after E. sorbillans infection. Reducing NOS expression and NO production with an NOS inhibitor (NG-nitro-L-arginine methyl ester hydrochloride) in infected B. mori significantly impeded the growth of E. sorbillans larvae. Moreover, the biosynthesis of 20-hydroxyecdysone (20E) in infected hosts was elevated with increasing NO production, and inhibiting NOS expression lowered 20E biosynthesis. More importantly, induced NO synthesis was required to eliminate intracellular bacterial pathogens that presumably competed for shared host resources. Inhibiting NOS expression down-regulated the transcription of antimicrobial peptide genes and increased the number of bacteria in parasitized hosts. Collectively, this study revealed a new perspective on the role of NO in host-parasitoid interactions and a novel mechanism for parasitoid regulation of host physiology to support its development.


Assuntos
Bombyx , Dípteros , Ecdisterona , Interações Hospedeiro-Parasita , Óxido Nítrico , Animais , Bombyx/genética , Bombyx/microbiologia , Bombyx/parasitologia , Dípteros/fisiologia , Ecdisterona/metabolismo , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase/genética
7.
Naturwissenschaften ; 111(3): 30, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758365

RESUMO

Succession patterns of carrion insects on large mammal's carrion has been widely studied, notably to estimate the post-mortem interval in forensic investigations as accurately as possible. However, little attention has been paid to the carrion insects living inside these bones once a carcass is skeletonized. One very recent study documented flies emerging from pig carcasses, and only scarce authors reported the presence of other carrion insects taking advantage of the bone marrow. We, thus, aimed to (1) estimate the frequency of inner-bone space colonization by carrion insects, with particular attention to bone-skipper flies; (2) identify the insects living inside the carrion bones; and (3) determine whether or not carrion insects found within the bones can successfully exit the bones and complete their development. We extensively sampled 185 large mammals' bones collected from twelve vulture feeding stations and four isolated carcasses in southwest France and northern Spain. Sampled bones were opened, and the insects found inside were identified. For two bones, foramen, i.e., the holes providing a natural entrance and exit to the bone's inner cavity, was monitored with a camera to assess the insect's putative exit. We describe the entomofauna, i.e., the set of insect species, living within the bones, and illustrate insects' ability to exit the bones for their subsequent development and maturity. These results are discussed in the framework of carrion insect conservation and forensic entomology perspectives.


Assuntos
Osso e Ossos , Entomologia Forense , Insetos , Mamíferos , Animais , Osso e Ossos/anatomia & histologia , Insetos/fisiologia , França , Espanha , Comportamento Alimentar/fisiologia , Dípteros/fisiologia , Dípteros/anatomia & histologia
8.
Bull Entomol Res ; 114(2): 230-236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38475984

RESUMO

As an environmental factor, temperature impacts the distribution of species and influences interspecific competition. The molecular chaperones encoded by small heat shock proteins (sHsps) are essential for rapid, appropriate responses to environmental stress. This study focuses on Hsp20.8, which encodes a temperature-responsive sHsp in Liriomyza trifolii, an insect pest that infests both agricultural and ornamental crops. Hsp20.8 expression was highest at 39℃ in L. trifolii pupae and adults, and expression levels were greater in pupae than in adults. Recombinant Hsp20.8 was expressed in Escherichia coli and conferred a higher survival rate than the empty vector to bacterial cells exposed to heat stress. RNA interference experiments were conducted using L. trifolii adults and prepupae and the knockdown of Hsp20.8 expression increased mortality in L. trifolii during heat stress. The results expand our understanding of sHsp function in Liriomyza spp. and the ongoing adaptation of this pest to climate change. In addition, this study is also important for predicting the distribution of invasive species and proposing new prevention and control strategies based on temperature adaptation.


Assuntos
Dípteros , Proteínas de Insetos , Animais , Dípteros/genética , Dípteros/fisiologia , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Temperatura Alta , Termotolerância , Pupa/crescimento & desenvolvimento , Pupa/genética , Pupa/metabolismo , Proteínas de Choque Térmico Pequenas/metabolismo , Proteínas de Choque Térmico Pequenas/genética , Interferência de RNA
9.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34531320

RESUMO

For the human observer, it can be difficult to follow the motion of small objects, especially when they move against background clutter. In contrast, insects efficiently do this, as evidenced by their ability to capture prey, pursue conspecifics, or defend territories, even in highly textured surrounds. We here recorded from target selective descending neurons (TSDNs), which likely subserve these impressive behaviors. To simulate the type of optic flow that would be generated by the pursuer's own movements through the world, we used the motion of a perspective corrected sparse dot field. We show that hoverfly TSDN responses to target motion are suppressed when such optic flow moves syn-directional to the target. Indeed, neural responses are strongly suppressed when targets move over either translational sideslip or rotational yaw. More strikingly, we show that TSDNs are facilitated by optic flow moving counterdirectional to the target, if the target moves horizontally. Furthermore, we show that a small, frontal spatial window of optic flow is enough to fully facilitate or suppress TSDN responses to target motion. We argue that such TSDN response facilitation could be beneficial in modulating corrective turns during target pursuit.


Assuntos
Dípteros/fisiologia , Neurônios/fisiologia , Fluxo Óptico/fisiologia , Animais , Dípteros/genética , Insetos/fisiologia , Percepção de Movimento/fisiologia , Visão Ocular/fisiologia , Percepção Visual/fisiologia
10.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33558235

RESUMO

Developing organisms typically mature earlier and at larger sizes in favorable growth conditions, while in rarer cases, maturity is delayed. The rarer reaction norm is easily accommodated by general life history models, whereas the common pattern is not. Theory suggests that a solution to this paradox lies in the existence of critical size thresholds at which maturation or metamorphosis can commence, and in the evolution of these threshold sizes in response to environmental variation. For example, ephemeral environments might favor the evolution of smaller thresholds, enabling earlier maturation. The threshold model makes two unique and untested predictions. First, reaction norms for age and size should steepen, and even change sign, with decreases in threshold size; second, food reductions at sizes below the threshold should delay maturation, while those occurring after the threshold should accelerate maturation. We test these predictions through food manipulations in five damselfly species that theory suggests should differ in threshold size. The results provide strong support for the threshold model's predictions. In all species, early food reductions delayed maturation, while late reductions accelerated maturation. Reaction norms were steeper, and the effect of food reductions changed from decelerating to accelerating at a much smaller size in species from ephemeral habitats. These results support the view that developmental thresholds can account for the widespread observation of negative correlations between age and size at maturity. Moreover, evolution of the threshold appears to be both predictable and central to the observed diversity of reaction norms for age and size at maturity.


Assuntos
Envelhecimento/genética , Tamanho Corporal/genética , Dípteros/genética , Evolução Molecular Direcionada , Interação Gene-Ambiente , Animais , Restrição Calórica , Dípteros/crescimento & desenvolvimento , Dípteros/fisiologia , Ecossistema , Características de História de Vida , Modelos Genéticos
11.
Ecotoxicol Environ Saf ; 270: 115861, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38154153

RESUMO

As agents in an emerging technology, Hermetia illucens (Linnaeus, 1758) (Diptera: Stratiomyidae) larvae, black soldier fly, have shown exciting potential for degrading antibiotics in organic solid waste, a process for which gut microorganisms play an important role. This study investigated the characteristics of larval gut bacterial communities effected by typical antibiotics. Initially, antibiotics significantly reduced the diversity of gut bacterial species. After 8 days, diversity recovered to similar to that of the control group in the chlortetracycline, tylosin, and sulfamethoxazole groups. Proteobacteria, Firmicutes, and Actinobacteriota were the dominant phyla at the initial BSFL gut. However, after 4 days treatment, the proportion of Actinobacteriota significantly decreased, but Bacteroidota notably increased. During the conversion process, 18, 18, 17, 21, and 19 core genera were present in the chlortetracycline, sulfamethoxazole, tylosin, norfloxacin, and gentamicin groups, respectively. Pseudomonas, Actinomyces, Morganella, Providencia and Klebsiella might be the important genera with extraordinary resistance and degradation to antibiotics. Statistical analyses of COGs showed that antibiotics changed the microbial community functions of BSFL gut. Compared with the control group, (i) the chlortetracycline, sulfamethoxazole, and tylosin groups showed significant increase in the classification functions of transcription, RNA processing and modification,and so on, (ii) the norfloxacin and gentamicin groups showed significant increase in defense mechanisms and other functions. Note that we categorized the response mechanisms of these classification functions to antibiotics into resistance and degradation. This provides a new perspective to deeply understand the joint biodegradation behavior of antibiotics in environments, and serves as an important reference for further development and utilization of microorganisms-assisted larvae for efficient degradation of antibiotics.


Assuntos
Clortetraciclina , Dípteros , Microbioma Gastrointestinal , Animais , Dípteros/fisiologia , Larva , Antibacterianos/farmacologia , Norfloxacino , Tilosina , Bactérias , Sulfametoxazol , Gentamicinas
12.
Proc Biol Sci ; 290(2005): 20230775, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37583323

RESUMO

Receivers of acoustic communication signals evaluate signal features to identify conspecifics. Changes in the ambient temperature can alter these features, rendering species recognition a challenge. To maintain effective communication, temperature coupling-changes in receiver signal preferences that parallel temperature-induced changes in signal parameters-occurs among genetically coupled signallers and receivers. Whether eavesdroppers of communication signals exhibit temperature coupling is unknown. Here, we investigate if the parasitoid fly Ormia ochracea, an eavesdropper of cricket calling songs, exhibits song pulse rate preferences that are temperature coupled. We use a high-speed treadmill system to record walking phonotaxis at three ambient temperatures (21, 25, and 30°C) in response to songs that varied in pulse rates (20 to 90 pulses per second). Total walking distance, peak steering velocity, angular heading, and the phonotaxis performance index varied with song pulse rates and ambient temperature. The peak of phonotaxis performance index preference functions became broader and shifted to higher pulse rate values at higher temperatures. Temperature-related changes in cricket songs between 21 and 30°C did not drastically affect the ability of flies to recognize cricket calling songs. These results confirm that temperature coupling can occur in eavesdroppers that are not genetically coupled with signallers.


Assuntos
Dípteros , Gryllidae , Animais , Temperatura , Dípteros/fisiologia , Acústica , Caminhada , Vocalização Animal/fisiologia , Comunicação Animal
13.
J Virol ; 96(15): e0075122, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35867566

RESUMO

Lumpy skin disease virus (LSDV) is a poxvirus that causes severe systemic disease in cattle and is spread by mechanical arthropod-borne transmission. This study quantified the acquisition and retention of LSDV by four species of Diptera (Stomoxys calcitrans, Aedes aegypti, Culex quinquefasciatus, and Culicoides nubeculosus) from cutaneous lesions, normal skin, and blood from a clinically affected animal. The acquisition and retention of LSDV by Ae. aegypti from an artificial membrane feeding system was also examined. Mathematical models of the data were generated to identify the parameters which influence insect acquisition and retention of LSDV. For all four insect species, the probability of acquiring LSDV was substantially greater when feeding on a lesion compared with feeding on normal skin or blood from a clinically affected animal. After feeding on a skin lesion LSDV was retained on the proboscis for a similar length of time (around 9 days) for all four species and for a shorter time in the rest of the body, ranging from 2.2 to 6.4 days. Acquisition and retention of LSDV by Ae. aegypti after feeding on an artificial membrane feeding system that contained a high titer of LSDV was comparable to feeding on a skin lesion on a clinically affected animal, supporting the use of this laboratory model as a replacement for some animal studies. This work reveals that the cutaneous lesions of LSD provide the high-titer source required for acquisition of the virus by insects, thereby enabling the mechanical vector-borne transmission. IMPORTANCE Lumpy skin disease virus (LSDV) is a high consequence pathogen of cattle that is rapidly expanding its geographical boundaries into new regions such as Europe and Asia. This expansion is promoted by the mechanical transmission of the virus via hematogenous arthropods. This study quantifies the acquisition and retention of LSDV by four species of blood-feeding insects and reveals that the cutaneous lesions of LSD provide the high titer virus source necessary for virus acquisition by the insects. An artificial membrane feeding system containing a high titer of LSDV was shown to be comparable to a skin lesion on a clinically affected animal when used as a virus source. This promotes the use of these laboratory-based systems as replacements for some animal studies. Overall, this work advances our understanding of the mechanical vector-borne transmission of LSDV and provides evidence to support the design of more effective disease control programmes.


Assuntos
Sangue , Dípteros , Comportamento Alimentar , Insetos Vetores , Doença Nodular Cutânea , Vírus da Doença Nodular Cutânea , Aedes/anatomia & histologia , Aedes/virologia , Animais , Bovinos/virologia , Ceratopogonidae/anatomia & histologia , Ceratopogonidae/virologia , Culex/anatomia & histologia , Culex/virologia , Dípteros/anatomia & histologia , Dípteros/fisiologia , Dípteros/virologia , Insetos Vetores/anatomia & histologia , Insetos Vetores/fisiologia , Insetos Vetores/virologia , Doença Nodular Cutânea/virologia , Vírus da Doença Nodular Cutânea/isolamento & purificação , Vírus da Doença Nodular Cutânea/fisiologia , Membranas Artificiais , Muscidae/anatomia & histologia , Muscidae/virologia , Fatores de Tempo
14.
New Phytol ; 239(4): 1490-1504, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36938986

RESUMO

Kleptomyiophily, where flowers imitate wounded insects to attract 'kleptoparasitic' flies as pollinators, is one of the most specialized types of floral mimicry and often involves physical trapping devices. However, the diversity of pollinators and functional floral traits involved in this form of mimicry remain poorly understood. We report a novel example of kleptomyiophily in the nontrapping flowers of Ceropegia gerrardii and explore the floral traits responsible for attracting pollinators. The pollinators, reproductive biology and floral traits (including epidermal surfaces, spectral reflectance and the composition of nectariferous petal secretions and scent) were investigated. Attractive volatiles were identified using electrophysiological and behavioural experiments. Ceropegia gerrardii was predominantly pollinated by kleptoparasitic Desmometopa spp. (Milichiidae) flies. The flower corollas extrude a protein- and sugar-containing secretion, similar to the haemolymph of wounded insects, on which the flies feed. Floral scent was chemically similar to that of injured honey bees. Four out of 24 electrophysiologically active compounds, all released by injured honey bees, were identified as key players in pollinator attraction. Our results suggest that C. gerrardii flowers chemically mimic wounded honey bees to attract kleptoparasitic flies and reward them with a secretion similar to the haemolymph on which they would normally feed.


Assuntos
Apocynaceae , Dípteros , Abelhas , Animais , Dípteros/fisiologia , Polinização/fisiologia , Insetos/fisiologia , Feromônios , Flores/fisiologia
15.
Artigo em Inglês | MEDLINE | ID: mdl-37477716

RESUMO

Many insects detect water bodies by observing the linearly polarised light which is reflected from the water surface. Polarotactic horseflies exhibit acrobatic manoeuvres above the water and are able to plunge on its surface, collect a droplet and fly away. This behaviour is extremely fast and has not yet been analysed. We recorded the flight patterns and kinematics of drinking horseflies using a pair of high-speed cameras. The animals of both sexes are attracted to water puddles where they make short, millisecond pitstops to collect a droplet of water that is then presumably drank "on the wing". Before the collection, the flies perform several low-altitude flybys above the puddle. After a few passes, the fly suddenly reverses its body orientation, decelerates, briefly touches the water surface and immediately flies away, usually with a droplet carried between its front legs. During the approach flight, the horseflies fly low but do not show any angular preference. Thus, they view the reflections from the sky, sun, or vegetation with a wide band of ventral ommatidia. Polarotaxis in drinking horseflies is a very robust visually guided behaviour, which operates at a broad range of intensities and various spectral compositions of reflected light.


Assuntos
Dípteros , Água , Masculino , Feminino , Animais , Dípteros/fisiologia , Insetos/fisiologia , Fenômenos Biomecânicos , Asas de Animais , Voo Animal/fisiologia
16.
Nat Rev Mol Cell Biol ; 12(9): 594-604, 2011 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-21850035

RESUMO

Morphogens are secreted signalling molecules that control the patterning and growth of developing organs. How morphogens regulate patterning is fairly well understood; however, how they control growth is less clear. Four principal models have been proposed to explain how the morphogenetic protein Decapentaplegic (DPP) controls the growth of the wing imaginal disc in the fly. Recent studies in this model system have provided a wealth of experimental data on growth and DPP gradient properties, as well as on the interactions of DPP with other signalling pathways. These findings have allowed a more precise formulation and evaluation of morphogenetic growth models. The insights into growth control by the DPP gradient will also be useful for understanding other morphogenetic growth systems.


Assuntos
Dípteros/crescimento & desenvolvimento , Crescimento/fisiologia , Morfogênese/genética , Animais , Compreensão , Dípteros/embriologia , Dípteros/fisiologia , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/fisiologia , Crescimento/genética , Humanos , Modelos Biológicos , Morfogênese/fisiologia
17.
Arch Insect Biochem Physiol ; 112(1): e21976, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36205611

RESUMO

Dipteran endoparasitoids avoid host immune response; however, antidefense components from the Dipterans are unknown. Infestation of commercial silkworm Bombyx mori Linnaeus (Lepidoptera: Bombycidae) by endoparasitoid Exorista bombycis Louis (Diptera: Tachinidae) induced immune reactions, cytotoxicity, granulation, degranulation, and augmented release of cytotoxic marker enzyme lactate dehydrogenase (LDH), and degranulation-mediator enzyme ß-hexosaminidase in hemocytes. In this study, by reverse phase high-performance liquid chromatography, fractions of E. bombycis larval tissue protein with antihemocytic activity are separated. From the fraction, peptides of hemocyte aggregation inhibitor protein (HAIP) and pyridoxamine phosphate oxidase (PNPO) are identified by mass spectrometry. Interacting partners of HAIP and PNPO are retrieved that further enhance the virulence of the parasitoid. PNPO and HAIP genes showed a four- to seven fold increase in expression in the integument of the parasitoid larva. Together, the dipteran endoparasitoid E. bombycis exploit antihemocyte activity to inhibit host defense reactions in addition to defense evasion contemplated.


Assuntos
Bombyx , Dípteros , Animais , Bombyx/genética , Interações Hospedeiro-Parasita , Dípteros/fisiologia , Larva/genética , Hemócitos
18.
Med Vet Entomol ; 37(1): 170-175, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36196866

RESUMO

Chemical signals are widespread in insects, but those resulting in interspecific communication (i.e., synomones) remain understudied. Here, we analysed chemicals left on substrates by two species of blow fly larvae, Lucilia sericata (Meigen) and Calliphora vomitoria (Linneaus) (Diptera: Calliphoridae), which can aggregate together on carrion. Using solid-phase microextraction and dynamic headspace analysis, we identified six compounds common to both species: the decanoic, tetradecanoic, pentadecanoic, hexadecanoic and octadecanoic acids, and the 2-ethylhexyl salicylate. We then tested the behavioural effects of the decanoic and pentadecanoic acids using binary-choice experiments, along with the (Z)-9-tricosene, a pheromone found in many arthropods. The time spent by a larva and its average crawling speed were measured in two sides of an arena, where only one contained a compound at 0.25 or 25 µg/µl. No effect was observed when testing the decanoic acid. The pentadecanoic acid only reduced the speed of C. vomitoria larvae at 25 µg/µl. Finally, L. sericata larvae spent less time in the side containing the (Z)-9-tricosene at 0.25 µg/µl, whereas C. vomitoria spent more time and crawled faster in this side at 25 µg/µl. Although these results did not directly evidence synomones, they suggest that the (Z)-9-tricosene could regulate larval aggregations on carrion.


Assuntos
Calliphoridae , Dípteros , Animais , Larva/fisiologia , Dípteros/fisiologia , Comportamento Alimentar
19.
Bull Entomol Res ; 113(3): 315-325, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36539340

RESUMO

Non-cultivated areas are resting, overwintering, feeding, and/or reproducing habitats for insects, and also places from where crop areas are colonized; thus, they are essential for understanding the biological control programs in agroecosystems. We developed a simulation model for a non-cultivated area of Buenos Aires province (Argentina), and we analyzed the control of Nezara viridula achieved by the action of two parasitoids: the oophagous Trissolcus basalis and the tachinid Trichopoda giacomellii, which attack older nymphs and adults. The model is a discrete time, deterministic, phenomenological, spatially homogeneous with a 1-week time interval simulation model, based on the age-structure and/or stage-structure of N. viridula and its two parasitoids. The host-parasitoid interactions were combined with a degree-day model affecting development times of T. giacomellii pupae and T. basalis pre-imaginal stages. The simultaneous attack of both parasitoid species enables the persistence of the system at low host densities, mediated by the functional response of the parasitoids, identified as population regulation factors. However, if only one parasitoid exists (i.e., only T. basalis or only T. giacomellii) the interaction N. viridula-parasitoid persisted but at higher density of N. viridula. These results explain the successful biological control of N. viridula after the introduction of T. basalis in the 1980s, when T. giacomellii was the only parasitoid present, unable to control N. viridula. Our model shows an indirect competition when both parasitoids are present: the attack of one of them diminished the potential number of hosts available to the other parasitoid species. In the field this interaction is obscured by the hibernation period which acted as a reset mechanism affecting the density and age/stage structure of all three populations. Our model was supported by field observations, and never exhibited the extinction of any of the parasitoids from the interaction.


Assuntos
Dípteros , Heterópteros , Himenópteros , Controle Biológico de Vetores , Animais , Dípteros/fisiologia , Ecossistema , Heterópteros/parasitologia , Heterópteros/fisiologia , Interações Hospedeiro-Parasita , Himenópteros/fisiologia
20.
Proc Natl Acad Sci U S A ; 117(22): 12201-12207, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32424090

RESUMO

The exemplary search capabilities of flying insects have established them as one of the most diverse taxa on Earth. However, we still lack the fundamental ability to quantify, represent, and predict trajectories under natural contexts to understand search and its applications. For example, flying insects have evolved in complex multimodal three-dimensional (3D) environments, but we do not yet understand which features of the natural world are used to locate distant objects. Here, we independently and dynamically manipulate 3D objects, airflow fields, and odor plumes in virtual reality over large spatial and temporal scales. We demonstrate that flies make use of features such as foreground segmentation, perspective, motion parallax, and integration of multiple modalities to navigate to objects in a complex 3D landscape while in flight. We first show that tethered flying insects of multiple species navigate to virtual 3D objects. Using the apple fly Rhagoletis pomonella, we then measure their reactive distance to objects and show that these flies use perspective and local parallax cues to distinguish and navigate to virtual objects of different sizes and distances. We also show that apple flies can orient in the absence of optic flow by using only directional airflow cues, and require simultaneous odor and directional airflow input for plume following to a host volatile blend. The elucidation of these features unlocks the opportunity to quantify parameters underlying insect behavior such as reactive space, optimal foraging, and dispersal, as well as develop strategies for pest management, pollination, robotics, and search algorithms.


Assuntos
Quimiotaxia , Sinais (Psicologia) , Dípteros/fisiologia , Percepção de Distância/fisiologia , Voo Animal/fisiologia , Odorantes , Animais , Simulação por Computador , Fluxo Óptico , Orientação , Interface Usuário-Computador
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