Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.024
Filtrar
1.
2.
Genes Dev ; 34(3-4): 194-208, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31919191

RESUMO

Promoting axon regeneration in the central and peripheral nervous system is of clinical importance in neural injury and neurodegenerative diseases. Both pro- and antiregeneration factors are being identified. We previously reported that the Rtca mediated RNA repair/splicing pathway restricts axon regeneration by inhibiting the nonconventional splicing of Xbp1 mRNA under cellular stress. However, the downstream effectors remain unknown. Here, through transcriptome profiling, we show that the tubulin polymerization-promoting protein (TPPP) ringmaker/ringer is dramatically increased in Rtca-deficient Drosophila sensory neurons, which is dependent on Xbp1. Ringer is expressed in sensory neurons before and after injury, and is cell-autonomously required for axon regeneration. While loss of ringer abolishes the regeneration enhancement in Rtca mutants, its overexpression is sufficient to promote regeneration both in the peripheral and central nervous system. Ringer maintains microtubule stability/dynamics with the microtubule-associated protein futsch/MAP1B, which is also required for axon regeneration. Furthermore, ringer lies downstream from and is negatively regulated by the microtubule-associated deacetylase HDAC6, which functions as a regeneration inhibitor. Taken together, our findings suggest that ringer acts as a hub for microtubule regulators that relays cellular status information, such as cellular stress, to the integrity of microtubules in order to instruct neuroregeneration.


Assuntos
Anilidas/metabolismo , Axônios/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Ácidos Hidroxâmicos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Regeneração/genética , Animais , Proteínas de Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/genética , Ligação Proteica , Processamento de RNA/genética , Células Receptoras Sensoriais/fisiologia
3.
Food Chem Toxicol ; 135: 110881, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622731

RESUMO

Dietary peptide has been of great interest because of its perspective in nutrition and health of human body. The aim of this study was to develop a dietary nutritional supplement exerting both antioxidant and anti-aging effects. Peptide, named as ERJ-CP, was prepared by mixing enzyme-treated royal jelly (ERJ) with collagen peptide (CP), showing stronger antioxidant activity in vitro. Drosophila was used as model animal to investigate anti-aging effect of ERJ-CP in vivo. ERJ-CP significantly prolonged the average life span of Drosophila treated with H2O2 and paraquat, reducing malondialdehyde (MDA) and protein carbonyl (PCO) levels in Drosophila. In addition, 3 mg/mL of ERJ-CP could prolong the lifespan of natural aging Drosophila by 11.16%. ERJ-CP could up-regulate the levels of total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), catalase (CAT) and down-regulate the contents of MDA and PCO. Moreover, the intake of ERJ-CP increased the food consumption, weight gain and exercise capacity of Drosophila. The results showed that ERJ-CP played a protective role in both antioxidant and anti-aging effects on Drosophila, and the anti-aging effect may be achieved by alleviating oxidative damage. It suggests that ERJ-CP could be developed as a health-promoting ingredient with antioxidant and anti-aging effects for human body.


Assuntos
Envelhecimento/efeitos dos fármacos , Colágeno/farmacologia , Drosophila/fisiologia , Ácidos Graxos/química , Estresse Oxidativo/efeitos dos fármacos , Aminoácidos/análise , Animais , Peso Corporal/efeitos dos fármacos , Colágeno/química , Comportamento Alimentar/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Longevidade/efeitos dos fármacos , Peso Molecular , Paraquat/farmacologia
4.
Insect Sci ; 27(2): 317-335, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30381878

RESUMO

Drosophila suzukii is an invasive pest causing severe damages to a large panel of cultivated crops. To facilitate its biocontrol with strategies such as sterile or incompatible insect techniques, D. suzukii must be mass-produced and then stored and transported under low temperature. Prolonged cold exposure induces chill injuries that can be mitigated if the cold period is interrupted with short warming intervals, referred to as fluctuating thermal regimes (FTR). In this study, we tested how to optimally use FTR to extend the shelf life of D. suzukii under cold storage. Several FTR parameters were assessed: temperature (15, 20, 25 °C), duration (0.5, 1, 2, 3 h), and frequency (every 12, 24, 36, 48 h) of warming intervals, in two wild-type lines and in two developmental stages (pupae and adults). Generally, FTR improved cold storage tolerance with respect to constant low temperatures (CLT). Cold mortality was lower when recovery temperature was 20 °C or higher, when duration was 2 h per day or longer, and when warming interruptions occurred frequently (every 12 or 24 h). Applying an optimized FTR protocol to adults greatly reduced cold mortality over long-term storage (up to 130 d). Consequences of FTR on fitness-related traits were also investigated. For adults, poststorage survival was unaffected by FTR, as was the case for female fecundity and male mating capacity. On the other hand, when cold storage occurred at pupal stage, poststorage survival and male mating capacity were altered under CLT, but not under FTR. After storage of pupae, female fecundity was lower under FTR compared to CLT, suggesting an energy trade-off between repair of chill damages and egg production. This study provides detailed information on the application and optimization of an FTR-based protocol for cold storage of D. suzukii that could be useful for the biocontrol of this pest.


Assuntos
Resposta ao Choque Frio , Drosophila/fisiologia , Traços de História de Vida , Animais , Feminino , Fertilidade , Masculino , Comportamento Sexual Animal
5.
Adv Exp Med Biol ; 1131: 857-879, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646537

RESUMO

In Drosophila photoreceptor cells, Ca2+ exerts regulatory functions that control the shape, duration, and amplitude of the light response. Ca2+ also orchestrates light adaptation allowing Drosophila to see in light intensity regimes that span several orders of magnitude ranging from single photons to bright sunlight. The prime source for Ca2+ elevation in the cytosol is Ca2+ influx from the extracellular space through light-activated TRP channels. This Ca2+ influx is counterbalanced by constitutive Ca2+ extrusion via the Na+/Ca2+ exchanger, CalX. The light-triggered rise in intracellular Ca2+ exerts its regulatory functions through interaction with about a dozen well-characterized Ca2+ and Ca2+/CaM binding proteins. In this review we will discuss the dynamic changes in Ca2+ concentration upon illumination of photoreceptor cells. We will present the proteins that are known to interact with Ca2+ (/CaM) and elucidate the physiological functions of these interactions.


Assuntos
Cálcio , Drosophila , Células Fotorreceptoras de Invertebrados , Transdução de Sinais , Animais , Antiporters/metabolismo , Cálcio/metabolismo , Drosophila/fisiologia , Proteínas de Drosophila/metabolismo , Luz , Células Fotorreceptoras de Invertebrados/fisiologia
6.
BMC Evol Biol ; 19(1): 204, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694548

RESUMO

BACKGROUND: Disentangling the selective factors shaping adaptive trait variation is an important but challenging task. Many studies-especially in Drosophila-have documented trait variation along latitudinal or altitudinal clines, but frequently lack resolution about specific environmental gradients that could be causal selective agents, and often do not investigate covariation between traits simultaneously. Here we examined variation in multiple macroecological factors across geographic space and their associations with variation in three physiological traits (desiccation resistance, UV resistance, and pigmentation) at both population and species scales, to address the role of abiotic environment in shaping trait variation. RESULTS: Using environmental data from collection locations of three North American Drosophila species-D. americana americana, D. americana texana and D. novamexicana-we identified two primary axes of macroecological variation; these differentiated species habitats and were strongly loaded for precipitation and moisture variables. In nine focal populations (three per species) assayed for each trait, we detected significant species-level variation for both desiccation resistance and pigmentation, but not for UV resistance. Species-level trait variation was consistent with differential natural selection imposed by variation in habitat water availability, although patterns of variation differed between desiccation resistance and pigmentation, and we found little evidence for pleiotropy between traits. CONCLUSIONS: Our multi-faceted approach enabled us to identify potential agents of natural selection and examine how they might influence the evolution of multiple traits at different evolutionary scales. Our findings highlight that environmental factors influence functional trait variation in ways that can be complex, and point to the importance of studies that examine these relationships at both population- and species-levels.


Assuntos
Drosophila/genética , Drosophila/fisiologia , Animais , Drosophila/classificação , Ecossistema , Feminino , Variação Genética , Masculino , América do Norte , Fenótipo , Pigmentação , Seleção Genética
7.
Nat Commun ; 10(1): 4796, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641138

RESUMO

Interneurons (INs) coordinate motoneuron activity to generate appropriate patterns of muscle contractions, providing animals with the ability to adjust their body posture and to move over a range of speeds. In Drosophila larvae several IN subtypes have been morphologically described and their function well documented. However, the general lack of molecular characterization of those INs prevents the identification of evolutionary counterparts in other animals, limiting our understanding of the principles underlying neuronal circuit organization and function. Here we characterize a restricted subset of neurons in the nerve cord expressing the Maf transcription factor Traffic Jam (TJ). We found that TJ+ neurons are highly diverse and selective activation of these different subtypes disrupts larval body posture and induces specific locomotor behaviors. Finally, we show that a small subset of TJ+ GABAergic INs, singled out by the expression of a unique transcription factors code, controls larval crawling speed.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Interneurônios/fisiologia , Fatores de Transcrição Maf Maior/metabolismo , Atividade Motora/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Animais , Animais Geneticamente Modificados , Drosophila/embriologia , Proteínas de Drosophila/genética , Embrião não Mamífero/fisiologia , Regulação da Expressão Gênica , Inativação Gênica , Larva/fisiologia , Locomoção/fisiologia , Fatores de Transcrição Maf Maior/genética , Proteínas Proto-Oncogênicas/genética , Raízes Nervosas Espinhais/fisiologia , Ácido gama-Aminobutírico/metabolismo
8.
BMC Genomics ; 20(1): 732, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606030

RESUMO

BACKGROUND: Relationships between an organism and its environment can be fundamental in the understanding how populations change over time and species arise. Local ecological conditions can shape variation at multiple levels, among these are the evolutionary history and trajectories of coding genes. This study examines the rate of molecular evolution at protein-coding genes throughout the genome in response to host adaptation in the cactophilic Drosophila mojavensis. These insects are intimately associated with cactus necroses, developing as larvae and feeding as adults in these necrotic tissues. Drosophila mojavensis is composed of four isolated populations across the deserts of western North America and each population has adapted to utilize different cacti that are chemically, nutritionally, and structurally distinct. RESULTS: High coverage Illumina sequencing was performed on three previously unsequenced populations of D. mojavensis. Genomes were assembled using the previously sequenced genome of D. mojavensis from Santa Catalina Island (USA) as a template. Protein coding genes were aligned across all four populations and rates of protein evolution were determined for all loci using a several approaches. CONCLUSIONS: Loci that exhibited elevated rates of molecular evolution tend to be shorter, have fewer exons, low expression, be transcriptionally responsive to cactus host use and have fixed expression differences across the four cactus host populations. Fast evolving genes were involved with metabolism, detoxification, chemosensory reception, reproduction and behavior. Results of this study give insight into the process and the genomic consequences of local ecological adaptation.


Assuntos
Cactaceae/parasitologia , Proteínas de Drosophila/genética , Drosophila/fisiologia , Sequenciamento Completo do Genoma/métodos , Adaptação Fisiológica , Animais , Drosophila/genética , Ecossistema , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Estados Unidos
9.
Immunity ; 51(4): 625-637.e3, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31564469

RESUMO

Preventing aberrant immune responses against the microbiota is essential for the health of the host. Microbiota-shed pathogen-associated molecular patterns translocate from the gut lumen into systemic circulation. Here, we examined the role of hemolymph (insect blood) filtration in regulating systemic responses to microbiota-derived peptidoglycan. Drosophila deficient for the transcription factor Klf15 (Klf15NN) are viable but lack nephrocytes-cells structurally and functionally homologous to the glomerular podocytes of the kidney. We found that Klf15NN flies were more resistant to infection than wild-type (WT) counterparts but exhibited a shortened lifespan. This was associated with constitutive Toll pathway activation triggered by excess peptidoglycan circulating in Klf15NN flies. In WT flies, peptidoglycan was removed from systemic circulation by nephrocytes through endocytosis and subsequent lysosomal degradation. Thus, renal filtration of microbiota-derived peptidoglycan maintains immune homeostasis in Drosophila, a function likely conserved in mammals and potentially relevant to the chronic immune activation seen in settings of impaired blood filtration.


Assuntos
Infecções Bacterianas/imunologia , Tecido Conjuntivo/fisiologia , Drosophila/fisiologia , Glomérulos Renais/fisiologia , Fatores de Transcrição Kruppel-Like/genética , Proteínas Nucleares/genética , Podócitos/fisiologia , Animais , Animais Geneticamente Modificados , Secreções Corporais , Proteínas de Drosophila/metabolismo , Endocitose , Homeostase , Imunidade Inata , Mamíferos , Microbiota , Receptores Toll-Like/metabolismo
10.
Nat Commun ; 10(1): 4289, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31537787

RESUMO

Neural information flow is inherently directional. To date, investigation of directional communication in the human structural connectome has been precluded by the inability of non-invasive neuroimaging methods to resolve axonal directionality. Here, we demonstrate that decentralized measures of network communication, applied to the undirected topology and geometry of brain networks, can infer putative directions of large-scale neural signalling. We propose the concept of send-receive communication asymmetry to characterize cortical regions as senders, receivers or neutral, based on differences between their incoming and outgoing communication efficiencies. Our results reveal a send-receive cortical hierarchy that recapitulates established organizational gradients differentiating sensory-motor and multimodal areas. We find that send-receive asymmetries are significantly associated with the directionality of effective connectivity derived from spectral dynamic causal modeling. Finally, using fruit fly, mouse and macaque connectomes, we provide further evidence suggesting that directionality of neural signalling is significantly encoded in the undirected architecture of nervous systems.


Assuntos
Encéfalo/fisiologia , Comunicação Celular/fisiologia , Rede Nervosa/fisiologia , Vias Neurais/fisiologia , Adulto , Animais , Conectoma , Drosophila/fisiologia , Feminino , Humanos , Macaca/fisiologia , Masculino , Camundongos , Modelos Neurológicos , Transdução de Sinais/fisiologia , Adulto Jovem
11.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540425

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is used as a research tool and clinical treatment for the non-clinical and clinical populations, to modulate brain plasticity. In the case of neurologic and psychiatric disease, there is significant evidence to suggest that rTMS plays an important role in the functional recovery after neurological dysfunction. However, the causal role for rTMS in the recovery of nervous dysfunction remains unclear. The purpose of the present study is to detect the regulation of rTMS on the excitatory neuronal transmission and specify the mode of action of rTMS on the neural plasticity using Drosophila whole brain. Therefore, we identified the effects of rTMS on the neural plasticity of central neural system (CNS) by detecting the electrophysiology properties of projection neurons (PNs) from adult Drosophila brain after rTMS. Using patch clamp recordings, we recorded the mini excitatory postsynaptic current (mEPSC) of PNs after rTMS at varying frequencies (1 Hz and 100 Hz) and intensities (1%, 10%, 50%, and 100%). Then, the chronic electrophysiology recordings, including mEPSC, spontaneous action potential (sAP), and calcium channel currents from PNs after rTMS at low frequency (1 Hz), with low intensity (1%) were detected and the properties of the recordings were analyzed. Finally, the frequency and decay time of mEPSC, the resting potential and frequency of sAP, and the current density and rise time of calcium channel currents were significantly changed by rTMS. Our work reveals that rTMS can be used as a tool to regulate the presynaptic function of neural circuit, by modulating the calcium channel in a frequency-, intensity- and time-dependent manner.


Assuntos
Drosophila/fisiologia , Plasticidade Neuronal , Estimulação Magnética Transcraniana , Potenciais de Ação , Animais , Encéfalo/fisiologia , Canais de Cálcio/metabolismo , Proteínas de Drosophila/metabolismo , Estimulação Magnética Transcraniana/métodos
12.
Cell Host Microbe ; 26(3): 412-425.e5, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31492656

RESUMO

Surviving infection requires immune and repair mechanisms. Developing organisms face the additional challenge of integrating these mechanisms with tightly controlled developmental processes. The larval Drosophila midgut lacks dedicated intestinal stem cells. We show that, upon infection, larvae perform limited repair using adult midgut precursors (AMPs). AMPs differentiate in response to damage to generate new enterocytes, transiently depleting their pool. Developmental delay allows for AMP reconstitution, ensuring the completion of metamorphosis. Notch signaling is required for the differentiation of AMPs into the encasing, niche-like peripheral cells (PCs), but not to differentiate PCs into enterocytes. Dpp (TGF-ß) signaling is sufficient, but not necessary, to induce PC differentiation into enterocytes. Infection-induced JAK-STAT pathway is both required and sufficient for differentiation of AMPs and PCs into new enterocytes. Altogether, this work highlights the constraints imposed by development on an organism's response to infection and demonstrates the transient use of adult precursors for tissue repair.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Trato Gastrointestinal/metabolismo , Larva/metabolismo , Animais , Diferenciação Celular , Modelos Animais de Doenças , Drosophila/microbiologia , Drosophila/fisiologia , Proteínas de Drosophila/genética , Enterócitos/metabolismo , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/patologia , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/patologia , Janus Quinases/metabolismo , Larva/imunologia , Larva/microbiologia , Metamorfose Biológica , Pectobacterium carotovorum/patogenicidade , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo , Transcriptoma
13.
Nat Commun ; 10(1): 3597, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399572

RESUMO

Hox proteins belong to a family of transcription factors with similar DNA binding specificities that control animal differentiation along the antero-posterior body axis. Hox proteins are expressed in partially overlapping regions where each one is responsible for the formation of particular organs and structures through the regulation of specific direct downstream targets. Thus, explaining how each Hox protein can selectively control its direct targets from those of another Hox protein is fundamental to understand animal development. Here we analyse a cis regulatory module directly regulated by seven different Drosophila Hox proteins and uncover how different Hox class proteins differentially control its expression. We find that regulation by one or another Hox protein depends on the combination of three modes: Hox-cofactor dependent DNA-binding specificity; Hox-monomer binding sites; and interaction with positive and negative Hox-collaborator proteins. Additionally, we find that similar regulation can be achieved by Amphioxus orthologs, suggesting these three mechanisms are conserved from insects to chordates.


Assuntos
Proteínas de Drosophila/metabolismo , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Drosophila/embriologia , Drosophila/genética , Drosophila/fisiologia , Proteínas de Drosophila/genética , Embrião não Mamífero , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Genes Homeobox , Genes de Insetos , Proteínas de Homeodomínio/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Elementos Reguladores de Transcrição/fisiologia , Fatores de Transcrição/genética
14.
Sci Total Environ ; 695: 133753, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31425981

RESUMO

Climate warming is threatening biodiversity worldwide. Climate specialists such as alpine species are especially likely to be vulnerable. Adaptation by rapid evolution is the only long-term option for survival of many species, but the adaptive evolutionary potential of heat resistance has not been assessed in an alpine invertebrate. Here, we show that the alpine fly Drosophila nigrosparsa cannot readily adapt to heat stress. Heat-exposed flies from a regime with increased ambient temperature and a regime with increased temperature plus artificial selection for heat tolerance were less heat tolerant than the control group. Increased ambient temperature affected negatively both fitness and competitiveness. Ecological niche models predicted the loss of three quarters of the climatically habitable areas of this fly by the end of this century. Our findings suggest that, alongside with other climate specialists, species from mountainous regions are highly vulnerable to climate warming and unlikely to adapt through evolutionary genetic changes.


Assuntos
Drosophila/fisiologia , Ecossistema , Termotolerância/fisiologia , Adaptação Fisiológica , Animais , Mudança Climática , Temperatura Alta
15.
J Chem Ecol ; 45(7): 626-637, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31257561

RESUMO

Since the first reports of damage by Drosophila suzukii, the spotted-wing Drosophila (SWD), over a decade ago in Europe, widespread efforts have been made to understand both the ecology and the evolution of this insect pest, especially due to its phylogenetic proximity to one of the original model organisms, D. melanogaster. In addition, researchers have sought to find economically viable solutions for the monitoring and management of this agricultural pest, which has now swept across much of Europe, North America and Asia. In a new direction of study, we present an investigation of plant-based chemistry, where we search for natural compounds that are structurally similar to known olfactory cues from parasitoid wasps that in turn are well-described ovipositional avoidance cues for many Drosophila species. Here we test 11 plant species across two plant genera, Nepeta and Actinidia, and while we find iridoid compounds in both, only those odorants from Actinidia are noted to be detected by the insect antenna, and in addition, found to be behaviorally active. Moreover, the Actinidia extracts resulted in oviposition avoidance when they were added to fruit samples in the laboratory. Thus we propose the possible efficacy of these plants or their extracted chemistry as a novel means for establishing a cost-effective integrated pest management strategy towards the control of this pest fly.


Assuntos
Actinidia/química , Produtos Biológicos/química , Drosophila/fisiologia , Controle de Insetos/métodos , Nepeta/química , Actinidia/metabolismo , Actinidia/parasitologia , Animais , Produtos Biológicos/farmacologia , Produtos Agrícolas , Drosophila/efeitos dos fármacos , Drosophila/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Nepeta/metabolismo , Nepeta/parasitologia , Oviposição/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia
16.
J Insect Sci ; 19(4)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31268546

RESUMO

Drosophila suzukii Matsumura (Diptera: Drosophilidae) is currently a major pest management challenge in berry and cherry production. This species has a winter morph phenotype with longer wings and increased melanization associated with survival in colder conditions. Measurements of wing morphology in Michigan D. suzukii collected during 2016 and 2017 showed that induction of this morph began in September and increased into December, correlated with decreasing temperature and day length. Importantly, we found that wing length increases along a continuous scale and there is overlap between the two morph types. We tested whether temperature or photoperiod elicited this phenotypic change using a factorial design with each preadult lifestage held at 10 or 25°C and 16:8 or 8:16 L:D. Our results support temperature as the main driver of transition to the winter morph for all immature stages. Comparing the reproductive capacity of winter morph flies in cold conditions and when previously acclimated to warm conditions, flies with the acclimation experience laid comparable numbers of eggs as the summer morphs at 25°C, indicating that winter morphs can reproduce after surviving cold periods. These results highlight the ability of D. suzukii to adapt to changing temperature conditions, allowing it to survive cold and also exploit warmer periods to build populations when conditions allow.


Assuntos
Aclimatação , Drosophila/fisiologia , Oviposição , Estações do Ano , Asas de Animais/anatomia & histologia , Animais , Drosophila/anatomia & histologia , Feminino , Masculino , Fenótipo , Fotoperíodo , Temperatura Ambiente
17.
Oxid Med Cell Longev ; 2019: 7823285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31320986

RESUMO

Being an assembly of highly sophisticated protein machines, cells depend heavily on proteostatic modules functionality and on adequate supply of energetic molecules for maintaining proteome stability. Yet, our understanding of the adaptations induced by multigenerational proteotoxic stress is limited. We report here that multigenerational (>80 generations) proteotoxic stress in OregonR flies induced by constant exposure to developmentally nonlethal doses of the proteasome inhibitor bortezomib (BTZ) (G80-BTZ flies) increased proteome instability and redox imbalance, reduced fecundity and body size, and caused neuromuscular defects; it also accelerated aging. G80-BTZ flies were mildly resistant to increased doses of BTZ and showed no age-related loss of proteasome activity; these adaptations correlated with sustained upregulation of proteostatic modules, which however occurred at the cost of minimal responses to increased BTZ doses and increased susceptibility to various types of additional proteotoxic stress, namely, autophagy inhibition or thermal stress. Multigenerational proteome instability and redox imbalance also caused metabolic reprogramming being evidenced by altered mitochondrial biogenesis and suppressed insulin/IGF-like signaling (IIS) in G80-BTZ flies. The toxic effects of multigenerational proteome instability could be partially mitigated by a low-protein diet that extended G80-BTZ flies' longevity. Overall, persistent proteotoxic stress triggers a highly conserved adaptive metabolic response mediated by the IIS pathway, which reallocates resources from growth and longevity to somatic preservation and stress tolerance. Yet, these trade-off adaptations occur at the cost of accelerated aging and/or reduced tolerance to additional stress, illustrating the limited buffering capacity of survival pathways.


Assuntos
Envelhecimento/fisiologia , Drosophila/fisiologia , Proteoma/metabolismo , Animais
18.
Elife ; 82019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31322499

RESUMO

Manipulating feeding circuits in freely moving animals is challenging, in part because the timing of sensory inputs is affected by the animal's behavior. To address this challenge in Drosophila, we developed the Sip-Triggered Optogenetic Behavior Enclosure ('STROBE'). The STROBE is a closed-looped system for real-time optogenetic activation of feeding flies, designed to evoke neural excitation coincident with food contact. We previously demonstrated the STROBE's utility in probing the valence of fly sensory neurons (Jaeger et al., 2018). Here we provide a thorough characterization of the STROBE system, demonstrate that STROBE-driven behavior is modified by hunger and the presence of taste ligands, and find that mushroom body dopaminergic input neurons and their respective post-synaptic partners drive opposing feeding behaviors following activation. Together, these results establish the STROBE as a new tool for dissecting fly feeding circuits and suggest a role for mushroom body circuits in processing naïve taste responses.


Assuntos
Drosophila/fisiologia , Entomologia/métodos , Comportamento Alimentar , Rede Nervosa/fisiologia , Optogenética/métodos , Animais
19.
PLoS One ; 14(7): e0218301, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31335864

RESUMO

Pachycrepoideus vindemmiae is a wasp that parasitizes and host-feeds on pupae of the invasive spotted-wing drosophila (SWD, Drosophila suzukii). Few studies have addressed interactions between these two species and little is known about the potential of this parasitoid as a biocontrol agent of SWD and the different variables that may affect it. Here, we investigated the impact of extrinsic and intrinsic factors on life-history traits of P. vindemmiae. Both constant (entire adulthood) and limited (30 minutes) supplies of water + honey, honey, or host increased parasitoid survival compared to controls (water or fasting). Water + honey caused the highest parasitoid survivals (35-60 days), independent of supply period, sex, and host availability. Females were intrinsically more resistant to water- and honey-deprivation than males, and host-feeding elevated such resistance even higher. Constant honey supply (either with or without water) supported the highest host-killing capacities (= capacity to kill hosts) (ca. 600 SWD pupae/wasp). However, in young females (4-9 days old), the impact of honey availability (with or without water) was insignificant while water deprivation (either with or without honey) caused the highest host-killing potential. This indicates that although sugar becomes a critical nutritional resource as females age, young females depend more on water than sugar to reproduce. Neither water nor honey affected the sex ratio of young females, but when we considered the entire adulthood, the availability of honey caused the lowest proportion of females (0.50), independent of water availability. Neither water nor honey affected parasitoid emergence rate (0.97), independent of female age. Based on survival and host-killing capacity, we conclude that P. vindemmiae has a tremendous biocontrol potential against SWD. Both limited and constant supply of water, sugar, and host increase parasitoid survival, while constant supply of water and/or honey enhance its host-killing potential and decrease sex ratio depending on maternal age.


Assuntos
Drosophila/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Himenópteros/patogenicidade , Reprodução/fisiologia , Animais , Drosophila/metabolismo , Drosophila/fisiologia , Feminino , Mel , Himenópteros/metabolismo , Himenópteros/fisiologia , Masculino , Pupa/parasitologia , Pupa/fisiologia , Razão de Masculinidade , Açúcares/metabolismo , Asas de Animais/fisiologia
20.
Elife ; 82019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31313987

RESUMO

Emerging evidence indicates the role of amino acid metabolism in sleep regulation. Here we demonstrate sleep-promoting effects of dietary threonine (SPET) in Drosophila. Dietary threonine markedly increased daily sleep amount and decreased the latency to sleep onset in a dose-dependent manner. High levels of synaptic GABA or pharmacological activation of metabotropic GABA receptors (GABAB-R) suppressed SPET. By contrast, synaptic blockade of GABAergic neurons or transgenic depletion of GABAB-R in the ellipsoid body R2 neurons enhanced sleep drive non-additively with SPET. Dietary threonine reduced GABA levels, weakened metabotropic GABA responses in R2 neurons, and ameliorated memory deficits in plasticity mutants. Moreover, genetic elevation of neuronal threonine levels was sufficient for facilitating sleep onset. Taken together, these data define threonine as a physiologically relevant, sleep-promoting molecule that may intimately link neuronal metabolism of amino acids to GABAergic control of sleep drive via the neuronal substrate of sleep homeostasis. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).


Assuntos
Drosophila/fisiologia , Neurônios GABAérgicos/metabolismo , Medicamentos Indutores do Sono/administração & dosagem , Sono , Treonina/administração & dosagem , Ração Animal , Animais , Drosophila/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA