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1.
Nat Commun ; 11(1): 4477, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901019

RESUMO

Individual cells detach from cohesive ensembles during development and can inappropriately separate in disease. Although much is known about how cells separate from epithelia, it remains unclear how cells disperse from clusters lacking apical-basal polarity, a hallmark of advanced epithelial cancers. Here, using live imaging of the developmental migration program of Drosophila primordial germ cells (PGCs), we show that cluster dispersal is accomplished by stabilizing and orienting migratory forces. PGCs utilize a G protein coupled receptor (GPCR), Tre1, to guide front-back migratory polarity radially from the cluster toward the endoderm. Posteriorly positioned myosin-dependent contractile forces pull on cell-cell contacts until cells release. Tre1 mutant cells migrate randomly with transient enrichment of the force machinery but fail to separate, indicating a temporal contractile force threshold for detachment. E-cadherin is retained on the cell surface during cell separation and augmenting cell-cell adhesion does not impede detachment. Notably, coordinated migration improves cluster dispersal efficiency by stabilizing cell-cell interfaces and facilitating symmetric pulling. We demonstrate that guidance of inherent migratory forces is sufficient to disperse cell clusters under physiological settings and present a paradigm for how such events could occur across development and disease.


Assuntos
Drosophila melanogaster/embriologia , Células Germinativas Embrionárias/fisiologia , Animais , Animais Geneticamente Modificados , Fenômenos Biomecânicos , Padronização Corporal/fisiologia , Caderinas/metabolismo , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Células Germinativas Embrionárias/citologia , Microscopia de Fluorescência por Excitação Multifotônica , Miosina Tipo II/metabolismo , Transdução de Sinais , Análise de Célula Única , Proteínas rho de Ligação ao GTP/metabolismo
2.
Nat Commun ; 11(1): 4491, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901033

RESUMO

The functionality of the nervous system requires transmission of information along axons with high speed and precision. Conductance velocity depends on axonal diameter whereas signaling precision requires a block of electrical crosstalk between axons, known as ephaptic coupling. Here, we use the peripheral nervous system of Drosophila larvae to determine how glia regulates axonal properties. We show that wrapping glial differentiation depends on gap junctions and FGF-signaling. Abnormal glial differentiation affects axonal diameter and conductance velocity and causes mild behavioral phenotypes that can be rescued by a sphingosine-rich diet. Ablation of wrapping glia does not further impair axonal diameter and conductance velocity but causes a prominent locomotion phenotype that cannot be rescued by sphingosine. Moreover, optogenetically evoked locomotor patterns do not depend on conductance speed but require the presence of wrapping glial processes. In conclusion, our data indicate that wrapping glia modulates both speed and precision of neuronal signaling.


Assuntos
Drosophila melanogaster/fisiologia , Animais , Animais Geneticamente Modificados , Axônios/fisiologia , Diferenciação Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Larva/citologia , Larva/fisiologia , Locomoção/fisiologia , Modelos Neurológicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Neuroglia/citologia , Neuroglia/fisiologia , Optogenética , Sistema Nervoso Periférico/citologia , Sistema Nervoso Periférico/fisiologia , Fenótipo , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Transdução de Sinais
3.
Proc Biol Sci ; 287(1935): 20201424, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32933446

RESUMO

Social interactions are thought to be a critical driver in the evolution of cognitive ability. Cooperative interactions, such as pair bonding, rather than competitive interactions have been largely implicated in the evolution of increased cognition. This is despite competition traditionally being a very strong driver of trait evolution. Males of many species track changes in their social environment and alter their reproductive strategies in response to anticipated levels of competition. We predict this to be cognitively challenging. Using a Drosophila melanogaster model, we are able to distinguish between the effects of a competitive environment versus generic social contact by exposing flies to same-sex same-species competition versus different species partners, shown to present non-competitive contacts. Males increase olfactory learning/memory and visual memory after exposure to conspecific males only, a pattern echoed by increased expression of synaptic genes and an increased need for sleep. For females, largely not affected by mating competition, the opposite pattern was seen. The results indicate that specific social contacts dependent on sex, not simply generic social stimulation, may be an important evolutionary driver for cognitive ability in fruit flies.


Assuntos
Cognição , Drosophila melanogaster/fisiologia , Animais , Feminino , Masculino , Memória , Fenótipo , Reprodução , Fatores Sexuais , Sono , Comportamento Social
4.
Nat Commun ; 11(1): 4782, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963223

RESUMO

Polycomb and Trithorax group proteins maintain stable epigenetic memory of gene expression states for some genes, but many targets show highly dynamic regulation. Here we combine experiment and theory to examine the mechanistic basis of these different modes of regulation. We present a mathematical model comprising a Polycomb/Trithorax response element (PRE/TRE) coupled to a promoter and including Drosophila developmental timing. The model accurately recapitulates published studies of PRE/TRE mediated epigenetic memory of both silencing and activation. With minimal parameter changes, the same model can also recapitulate experimental data for a different PRE/TRE that allows dynamic regulation of its target gene. The model predicts that both cell cycle length and PRE/TRE identity are critical for determining whether the system gives stable memory or dynamic regulation. Our work provides a simple unifying framework for a rich repertoire of PRE/TRE functions, and thus provides insights into  genome-wide Polycomb/Trithorax regulation.


Assuntos
Proteínas Cromossômicas não Histona/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Epigenômica , Regulação da Expressão Gênica no Desenvolvimento/genética , Modelos Teóricos , Complexo Repressor Polycomb 1/genética , Animais , Divisão Celular , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Epigênese Genética , Feminino , Inativação Gênica , Complexo Repressor Polycomb 1/metabolismo , Proteínas do Grupo Polycomb/metabolismo , Regiões Promotoras Genéticas , Elementos de Resposta
6.
Nat Commun ; 11(1): 3962, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32770059

RESUMO

Social context can dampen or amplify the perception of touch, and touch in turn conveys nuanced social information. However, the neural mechanism behind social regulation of mechanosensation is largely elusive. Here we report that fruit flies exhibit a strong defensive response to mechanical stimuli to their wings. In contrast, virgin female flies being courted by a male show a compromised defensive response to the stimuli, but following mating the response is enhanced. This state-dependent switch is mediated by a functional reconfiguration of a neural circuit labelled with the Tmc-L gene in the ventral nerve cord. The circuit receives excitatory inputs from peripheral mechanoreceptors and coordinates the defensive response. While male cues suppress it via a doublesex (dsx) neuronal pathway, mating sensitizes it by stimulating a group of uterine neurons and consequently activating a leucokinin-dependent pathway. Such a modulation is crucial for the balance between defense against body contacts and sexual receptivity.


Assuntos
Drosophila melanogaster/fisiologia , Vias Neurais/fisiologia , Comportamento Sexual Animal/fisiologia , Alelos , Animais , Corte , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Feminino , Neurônios GABAérgicos/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Masculino , Mecanorreceptores/metabolismo , Mutação/genética , Neuropeptídeos/metabolismo , Útero/inervação , Asas de Animais/inervação
7.
PLoS Genet ; 16(8): e1008963, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780743

RESUMO

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Memória de Longo Prazo/fisiologia , Neurônios/metabolismo , Olfato/genética , Transativadores/genética , Animais , Animais Geneticamente Modificados , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Biossíntese de Proteínas/genética , Recompensa , Olfato/fisiologia , Transmissão Sináptica/genética , Água
8.
Nat Commun ; 11(1): 4236, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32843654

RESUMO

The impact of commensal bacteria on the host arises from complex microbial-diet-host interactions. Mapping metabolic interactions in gut microbial communities is therefore key to understand how the microbiome influences the host. Here we use an interdisciplinary approach including isotope-resolved metabolomics to show that in Drosophila melanogaster, Acetobacter pomorum (Ap) and Lactobacillus plantarum (Lp) a syntrophic relationship is established to overcome detrimental host diets and identify Ap as the bacterium altering the host's feeding decisions. Specifically, we show that Ap uses the lactate produced by Lp to supply amino acids that are essential to Lp, allowing it to grow in imbalanced diets. Lactate is also necessary and sufficient for Ap to alter the fly's protein appetite. Our data show that gut bacterial communities use metabolic interactions to become resilient to detrimental host diets. These interactions also ensure the constant flow of metabolites used by the microbiome to alter reproduction and host behaviour.


Assuntos
Dieta , Drosophila melanogaster/microbiologia , Drosophila melanogaster/fisiologia , Microbioma Gastrointestinal/fisiologia , Acetobacter/crescimento & desenvolvimento , Acetobacter/metabolismo , Aminoácidos/deficiência , Aminoácidos/metabolismo , Animais , Apetite , Feminino , Preferências Alimentares , Interações entre Hospedeiro e Microrganismos , Ácido Láctico/metabolismo , Lactobacillus plantarum/crescimento & desenvolvimento , Lactobacillus plantarum/metabolismo , Redes e Vias Metabólicas , Metabolômica , Consórcios Microbianos , Reprodução
9.
PLoS One ; 15(8): e0237986, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841282

RESUMO

Insects experience a diversity of subtoxic and/or toxic xenobiotics through exposure to pesticides and, in the case of herbivorous insects, through plant defensive compounds in their diets. Many insects are also concurrently exposed to antioxidants in their diets. The impact of dietary antioxidants on the toxicity of xenobiotics in insects is not well understood, in part due to the challenge of developing appropriate systems in which doses and exposure times (of both the antioxidants and the xenobiotics) can be controlled and outcomes can be easily measured. However, in Drosophila melanogaster, a well-established insect model system, both dietary factors and pesticide exposure can be easily controlled. Additionally, the mode of action and xenobiotic metabolism of dichlorodiphenyltrichloroethane (DDT), a highly persistent neurotoxic organochlorine insecticide that is detected widely in the environment, have been well studied in DDT-susceptible and -resistant strains. Using a glass-vial bioassay system with blue diet as the food source, seven compounds with known antioxidant effects (ascorbic acid, ß-carotene, glutathione, α-lipoic acid, melatonin, minocycline, and serotonin) were orally tested for their impact on DDT toxicity across three strains of D. melanogaster: one highly susceptible to DDT (Canton-S), one mildly susceptible (91-C), and one highly resistant (91-R). Three of the antioxidants (serotonin, ascorbic acid, and ß-carotene) significantly impacted the toxicity of DDT in one or more strains. Fly strain and gender, antioxidant type, and antioxidant dose all affected the relative toxicity of DDT. Our work demonstrates that dietary antioxidants can potentially alter the toxicity of a xenobiotic in an insect population.


Assuntos
Antioxidantes/farmacologia , DDT/toxicidade , Dieta , Drosophila melanogaster/efeitos dos fármacos , Resistência a Inseticidas/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Genótipo , Masculino , Serotonina/farmacologia , Caracteres Sexuais
10.
PLoS Pathog ; 16(8): e1008794, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32813725

RESUMO

Wolbachia are the world's most common, maternally-inherited, arthropod endosymbionts. Their worldwide distribution is due, in part, to a selfish drive system termed cytoplasmic incompatibility (CI) that confers a relative fitness advantage to females that transmit Wolbachia to their offspring. CI results in embryonic death when infected males mate with uninfected females but not infected females. Under the Two-by-One genetic model of CI, males expressing the two phage WO proteins CifA and CifB cause CI, and females expressing CifA rescue CI. While each protein is predicted to harbor three functional domains, there is no knowledge on how sites across these Cif domains, rather than in any one particular domain, contribute to CI and rescue. Here, we use evolution-guided, substitution mutagenesis of conserved amino acids across the Cif proteins, coupled with transgenic expression in uninfected Drosophila melanogaster, to determine the functional impacts of conserved residues evolving mostly under purifying selection. We report that amino acids in CifA's N-terminal unannotated region and annotated catalase-related domain are important for both complete CI and rescue, whereas C-terminal residues in CifA's putative domain of unknown function are solely important for CI. Moreover, conserved CifB amino acids in the predicted nucleases, peptidase, and unannotated regions are essential for CI. Taken together, these findings indicate that (i) all CifA amino acids determined to be crucial in rescue are correspondingly crucial in CI, (ii) an additional set of CifA amino acids are uniquely important in CI, and (iii) CifB amino acids across the protein, rather than in one particular domain, are all crucial for CI. We discuss how these findings advance an expanded view of Cif protein evolution and function, inform the mechanistic and biochemical bases of Cif-induced CI/rescue, and continue to substantiate the Two-by-One genetic model of CI.


Assuntos
Proteínas de Bactérias/metabolismo , Evolução Biológica , Citoplasma/metabolismo , Drosophila melanogaster/microbiologia , Infecções por Bactérias Gram-Negativas/metabolismo , Mutação , Wolbachia/fisiologia , Animais , Animais Geneticamente Modificados/microbiologia , Animais Geneticamente Modificados/fisiologia , Proteínas de Bactérias/genética , Citoplasma/microbiologia , Drosophila melanogaster/fisiologia , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Masculino
11.
PLoS Biol ; 18(7): e3000712, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32663220

RESUMO

Tools enabling closed-loop experiments are crucial to delineate causal relationships between the activity of genetically labeled neurons and specific behaviors. We developed the Raspberry Pi Virtual Reality (PiVR) system to conduct closed-loop optogenetic stimulation of neural functions in unrestrained animals. PiVR is an experimental platform that operates at high temporal resolution (70 Hz) with low latencies (<30 milliseconds), while being affordable (

Assuntos
Comportamento Animal/fisiologia , Drosophila melanogaster/fisiologia , Optogenética , Córtex Sensório-Motor/fisiologia , Realidade Virtual , Animais , Quimiotaxia , Larva/fisiologia , Luz , Locomoção , Masculino , Neurônios/fisiologia , Odorantes , Sensação/fisiologia , Software , Paladar/fisiologia , Peixe-Zebra
12.
PLoS One ; 15(7): e0236318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726319

RESUMO

Lately, Drosophila has been favored as a model in sleep and circadian rhythm research due to its conserved mechanism and easily manageable operation. These studies have revealed the sophisticated parameters in whole-day sleep profiles of Drosophila, drawing connections between Drosophila sleep and human sleep. In this study, we tested several sleep deprivation protocols (mechanical shakes and light interruptions) on Drosophila and delineated their influences on Drosophila sleep. We applied a daytime light-deprivation protocol (DD) mimicking jet-lag to screen drugs that alleviate sleep deprivation. Characteristically, classical sleep-aid compounds exhibited different forms of influence: phenobarbital and pentobarbital modified total sleep time, while melatonin only shortened the latency to sleep. Such results construct the basis for further research on sleep benefits in other treatments in Drosophila. We screened seven herb extracts, and found very diverse results regarding their effect on sleep regulation. For instance, Panax notoginseng and Withania somnifera extracts displayed potent influence on total sleep time, while Melissa officinalis increased the number of sleep episodes. By comparing these treatments, we were able to rank drug potency in different aspects of sleep regulation. Notably, we also confirmed the presence of sleep difficulties in a Drosophila Alzheimer's disease (AD) model with an overexpression of human Abeta, and recognized clear differences between the portfolios of drug screening effects in AD flies and in the control group. Overall, potential drug candidates and receipts for sleep problems can be identified separately for normal and AD Drosophila populations, outlining Drosophila's potential in drug screening tests in other populations if combined with the use of other genetic disease tools.


Assuntos
Extratos Vegetais/farmacologia , Privação do Sono/tratamento farmacológico , Transtornos do Sono-Vigília/tratamento farmacológico , Sono/fisiologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/genética , Animais , Ritmo Circadiano/efeitos dos fármacos , Modelos Animais de Doenças , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Regulação da Expressão Gênica/genética , Humanos , Melatonina/farmacologia , Mutação , Panax notoginseng/química , Fenobarbital/farmacologia , Extratos Vegetais/química , Sono/efeitos dos fármacos , Sono/genética , Privação do Sono/genética , Privação do Sono/fisiopatologia , Transtornos do Sono-Vigília/genética , Transtornos do Sono-Vigília/fisiopatologia , Withania/química
13.
BMC Evol Biol ; 20(1): 93, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727355

RESUMO

BACKGROUND: The adaptive significance of phenotypic changes elicited by environmental conditions experienced early in life has long attracted attention in evolutionary biology. In this study, we used Drosophila melanogaster to test whether the developmental diet produces phenotypes better adapted to cope with similar nutritional conditions later in life. To discriminate among competing hypotheses on the underlying nature of developmental plasticity, we employed a full factorial design with several developmental and adult diets. Specifically, we examined the effects of early- and late-life diets (by varying their yeast and sugar contents) on reproductive fitness and on the amount of energy reserves (fat and glycogen) in two wild-caught populations. RESULTS: We found that individuals that had developed on either low-yeast or high-sugar diet showed decreased reproductive performance regardless of their adult nutritional environment. The lower reproductive fitness might be caused by smaller body size and reduced ovariole number. Overall, these results are consistent with the silver spoon concept, which posits that development in a suboptimal environment negatively affects fitness-associated traits. On the other hand, the higher amount of energy reserves (fat) in individuals that had developed in a suboptimal environment might represent either an adaptive response or a side-effect of compensatory feeding. CONCLUSION: Our findings suggest that the observed differences in the adult physiology induced by early-life diet likely result from inevitable and general effects of nutrition on the development of reproductive and metabolic organs, rather than from adaptive mechanisms.


Assuntos
Dieta , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Tecido Adiposo/metabolismo , Animais , Tamanho Corporal , Metabolismo Energético , Feminino , Fertilidade , Aptidão Genética , Glicogênio/metabolismo , Masculino , Fenótipo , Reprodução , Açúcares/análise , Leveduras
14.
Proc Natl Acad Sci U S A ; 117(29): 17094-17103, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32611817

RESUMO

Declining ejaculate performance with male age is taxonomically widespread and has broad fitness consequences. Ejaculate success requires fully functional germline (sperm) and soma (seminal fluid) components. However, some aging theories predict that resources should be preferentially diverted to the germline at the expense of the soma, suggesting differential impacts of aging on sperm and seminal fluid and trade-offs between them or, more broadly, between reproduction and lifespan. While harmful effects of male age on sperm are well known, we do not know how much seminal fluid deteriorates in comparison. Moreover, given the predicted trade-offs, it remains unclear whether systemic lifespan-extending interventions could ameliorate the declining performance of the ejaculate as a whole. Here, we address these problems using Drosophila melanogaster. We demonstrate that seminal fluid deterioration contributes to male reproductive decline via mating-dependent mechanisms that include posttranslational modifications to seminal proteins and altered seminal proteome composition and transfer. Additionally, we find that sperm production declines chronologically with age, invariant to mating activity such that older multiply mated males become infertile principally via reduced sperm transfer and viability. Our data, therefore, support the idea that both germline and soma components of the ejaculate contribute to male reproductive aging but reveal a mismatch in their aging patterns. Our data do not generally support the idea that the germline is prioritized over soma, at least, within the ejaculate. Moreover, we find that lifespan-extending systemic down-regulation of insulin signaling results in improved late-life ejaculate performance, indicating simultaneous amelioration of both somatic and reproductive aging.


Assuntos
Envelhecimento , Drosophila melanogaster , Proteínas de Plasma Seminal , Espermatozoides , Envelhecimento/genética , Envelhecimento/fisiologia , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Fertilidade/genética , Fertilidade/fisiologia , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Masculino , Proteoma/análise , Proteoma/genética , Proteoma/fisiologia , Proteínas de Plasma Seminal/análise , Proteínas de Plasma Seminal/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/química , Espermatozoides/fisiologia
15.
Nature ; 584(7821): 415-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641829

RESUMO

Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences1-3. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases4. Here we report that steroid signalling in Drosophila from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.


Assuntos
Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Intestinos/crescimento & desenvolvimento , Longevidade/fisiologia , Tamanho do Órgão/fisiologia , Ovário/metabolismo , Esteroides/metabolismo , Envelhecimento , Animais , Carcinogênese , Proliferação de Células , Copulação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Ecdisona/metabolismo , Feminino , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/anatomia & histologia , Intestinos/citologia , Intestinos/patologia , Masculino , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
16.
J Vis Exp ; (159)2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32478750

RESUMO

Drosophila serves as a useful model for assessing synaptic structure and function associated with neurodegenerative diseases. While much work has focused on neuromuscular junctions (NMJs) in Drosophila larvae, assessing synaptic integrity in adult Drosophila has received much less attention. Here we provide a straightforward method for dissection of the dorsal longitudinal muscles (DLMs), which are required for flight ability. In addition to flight as a behavioral readout, this dissection allows for the both DLM synapses and muscle tissue to be amenable to structural analysis using fluorescently labeled antibodies for synaptic markers or proteins of interest. This protocol allows for the evaluation of the structural integrity of synapses in adult Drosophila during aging to model the progressive, age-dependent nature of most neurodegenerative diseases.


Assuntos
Envelhecimento/patologia , Drosophila melanogaster/fisiologia , Degeneração Neural/patologia , Sinapses/metabolismo , Esclerose Amiotrófica Lateral/patologia , Animais , Animais Geneticamente Modificados , Denervação , Dissecação , Congelamento , Humanos , Larva/metabolismo , Junção Neuromuscular/fisiologia , Coloração e Rotulagem , Tórax
17.
Proc Natl Acad Sci U S A ; 117(26): 15293-15304, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32541062

RESUMO

Organisms possess photoperiodic timing mechanisms to detect variations in day length and temperature as the seasons progress. The nature of the molecular mechanisms interpreting and signaling these environmental changes to elicit downstream neuroendocrine and physiological responses are just starting to emerge. Here, we demonstrate that, in Drosophila melanogaster, EYES ABSENT (EYA) acts as a seasonal sensor by interpreting photoperiodic and temperature changes to trigger appropriate physiological responses. We observed that tissue-specific genetic manipulation of eya expression is sufficient to disrupt the ability of flies to sense seasonal cues, thereby altering the extent of female reproductive dormancy. Specifically, we observed that EYA proteins, which peak at night in short photoperiod and accumulate at higher levels in the cold, promote reproductive dormancy in female D. melanogaster Furthermore, we provide evidence indicating that the role of EYA in photoperiodism and temperature sensing is aided by the stabilizing action of the light-sensitive circadian clock protein TIMELESS (TIM). We postulate that increased stability and level of TIM at night under short photoperiod together with the production of cold-induced and light-insensitive TIM isoforms facilitate EYA accumulation in winter conditions. This is supported by our observations that tim null mutants exhibit reduced incidence of reproductive dormancy in simulated winter conditions, while flies overexpressing tim show an increased incidence of reproductive dormancy even in long photoperiod.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Proteínas do Olho/metabolismo , Fotoperíodo , Estações do Ano , Temperatura , Animais , Proteínas de Drosophila/genética , Proteínas do Olho/genética , Regulação da Expressão Gênica/fisiologia , Reprodução
18.
PLoS Genet ; 16(6): e1008885, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32559217

RESUMO

Regulation of cell junctions is crucial for the integrity of epithelial tissues and organs. Cell junctions also play roles in controlling cell proliferation for organ growth. Translationally controlled tumor protein (TCTP) is a conserved protein involved in growth control, but its role in cell junctions is unknown. Here we show that Drosophila Tctp directly interacts with the septate junction protein Coracle (Cora) to regulate epithelial integrity and organ growth. Tctp localizes together with Cora in the epidermis of the embryo. Loss of Cora reduces the level of Tctp in the epidermis but not vice versa. cora/+ or Tctp/+ single heterozygotes develop normally to adulthood. However, double heterozygotes for cora and Tctp mutations show severe disruption of epithelia causing synthetic lethality in the embryo. Double knockdown of Cora and Tctp in eye imaginal disc synergistically leads to disruption of the eye disc, resulting in a severe reduction or loss of eye and head. Conversely, double knockdown of Cora and Tctp in wing disc causes overgrowth as well as cell death. Inhibition of cell death under this condition causes hyperplastic growth of the wing disc. Tctp also shows direct and functional interaction with Cora-associated factors like Yurt and Na+/K+-ATPase. This study suggests that proper levels of Tctp and Cora are essential for the maintenance of the Cora complex and the integrity of epithelia. Our data also provide evidence that both Cora and Tctp are required to suppress overgrowth in developing wing.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Epitélio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Asas de Animais/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados , Proliferação de Células/genética , Proteínas de Drosophila/genética , Embrião não Mamífero , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Discos Imaginais/crescimento & desenvolvimento , Junções Intercelulares/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/genética , Morfogênese/genética , Mutações Sintéticas Letais , Asas de Animais/metabolismo
19.
Nat Commun ; 11(1): 2592, 2020 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444642

RESUMO

Mitochondrial aging, which results in mitochondrial dysfunction, is strongly linked to many age-related diseases. Aging is associated with mitochondrial enlargement and transport of cytosolic proteins into mitochondria. The underlying homeostatic mechanisms that regulate mitochondrial morphology and function, and their breakdown during aging, remain unclear. Here, we identify a mitochondrial protein trafficking pathway in Drosophila melanogaster involving the mitochondria-associated protein Dosmit. Dosmit induces mitochondrial enlargement and the formation of double-membraned vesicles containing cytosolic protein within mitochondria. The rate of vesicle formation increases with age. Vesicles originate from the outer mitochondrial membrane as observed by tracking Tom20 localization, and the process is mediated by the mitochondria-associated Rab32 protein. Dosmit expression level is closely linked to the rate of ubiquitinated protein aggregation, which are themselves associated with age-related diseases. The mitochondrial protein trafficking route mediated by Dosmit offers a promising target for future age-related mitochondrial disease therapies.


Assuntos
Citoplasma/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Mitocôndrias/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Fatores Etários , Animais , Animais Geneticamente Modificados , Proteínas do Citoesqueleto/metabolismo , Drosophila melanogaster/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Longevidade , Camundongos , Mitocôndrias/genética , Mitocôndrias/patologia , Domínios Proteicos , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Vesículas Transportadoras/metabolismo , Proteínas Ubiquitinadas/metabolismo
20.
Chemosphere ; 253: 126629, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283422

RESUMO

Recent reports demonstrate that octopamine receptor (OR) agonists such as formamidine pesticides cause reproductive and developmental toxicity through endocrine disrupting effects in both humans and animals. Herein, we studied the effects of different sublethal concentrations of OR agonists, Amitraz and Chlordimeform, on growth, development, and reproduction of D. melanogaster from a genotype perspective view. As a result, the sublethal concentrations for both OR agonists delayed the developmental time including pupation and eclosion. It significantly reduced the lifespan, eclosion rate, and production of eggs. The mRNA expression of genes relevant for development and metabolism was significantly changed after exposure to sublethal concentrations of both OR agonists. Octopamine receptor in mushroom bodies (Oamb), trehalase enzyme (Treh), hemocyte proliferation (RyR), and immune response (IM4) genes were upregulated whereas, trehalose sugar (Tret1-1), mixed function oxidase enzyme (Cyp9f2), lifespan (Atg7), male mating behavior (Ple), female fertility (Ddc), and lipid metabolism (Sxe2) genes were downregulated. These results support the conclusion that OR agonists activate the octopamine receptor in D. melanogaster leading to an increase of trehalase enzyme activity and degradation of trehalose sugar into free glucose which results in rapid energy exhaustion, hyperexcitation, and disturbing of the octopaminergic system in D. melanogaster.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Octopamina/toxicidade , Amidinas , Animais , Proteína 7 Relacionada à Autofagia , Comportamento Animal , Drosophila melanogaster/efeitos dos fármacos , Feminino , Masculino , Metabolismo/genética , Receptores de Amina Biogênica , Toluidinas
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