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1.
Nat Commun ; 12(1): 5178, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462441

RESUMO

Animals maintain metabolic homeostasis by modulating the activity of specialized organs that adjust internal metabolism to external conditions. However, the hormonal signals coordinating these functions are incompletely characterized. Here we show that six neurosecretory cells in the Drosophila central nervous system respond to circulating nutrient levels by releasing Capa hormones, homologs of mammalian neuromedin U, which activate the Capa receptor (CapaR) in peripheral tissues to control energy homeostasis. Loss of Capa/CapaR signaling causes intestinal hypomotility and impaired nutrient absorption, which gradually deplete internal nutrient stores and reduce organismal lifespan. Conversely, increased Capa/CapaR activity increases fluid and waste excretion. Furthermore, Capa/CapaR inhibits the release of glucagon-like adipokinetic hormone from the corpora cardiaca, which restricts energy mobilization from adipose tissue to avoid harmful hyperglycemia. Our results suggest that the Capa/CapaR circuit occupies a central node in a homeostatic program that facilitates the digestion and absorption of nutrients and regulates systemic energy balance.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Neuropeptídeos/metabolismo , Nutrientes/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Metabolismo Energético , Feminino , Homeostase , Hormônios de Inseto/metabolismo , Longevidade , Masculino , Neuropeptídeos/genética , Oligopeptídeos/metabolismo , Ácido Pirrolidonocarboxílico/análogos & derivados , Ácido Pirrolidonocarboxílico/metabolismo , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais
2.
Nat Commun ; 12(1): 4987, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404776

RESUMO

In Drosophila, direction-selective neurons implement a mechanism of motion computation similar to cortical neurons, using contrast-opponent receptive fields with ON and OFF subfields. It is not clear how the presynaptic circuitry of direction-selective neurons in the OFF pathway supports this computation if all major inputs are OFF-rectified neurons. Here, we reveal the biological substrate for motion computation in the OFF pathway. Three interneurons, Tm2, Tm9 and CT1, provide information about ON stimuli to the OFF direction-selective neuron T5 across its receptive field, supporting a contrast-opponent receptive field organization. Consistent with its prominent role in motion detection, variability in Tm9 receptive field properties transfers to T5, and calcium decrements in Tm9 in response to ON stimuli persist across behavioral states, while spatial tuning is sharpened by active behavior. Together, our work shows how a key neuronal computation is implemented by its constituent neuronal circuit elements to ensure direction selectivity.


Assuntos
Drosophila/metabolismo , Percepção de Movimento/fisiologia , Movimento (Física) , Neurônios/metabolismo , Animais , Cálcio/metabolismo , Clorfenamidina , Drosophila/genética , Drosophila melanogaster/metabolismo , Feminino , Interneurônios/metabolismo
3.
Nat Commun ; 12(1): 4818, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376687

RESUMO

The enteroendocrine cell (EEC)-derived incretins play a pivotal role in regulating the secretion of glucagon and insulins in mammals. Although glucagon-like and insulin-like hormones have been found across animal phyla, incretin-like EEC-derived hormones have not yet been characterised in invertebrates. Here, we show that the midgut-derived hormone, neuropeptide F (NPF), acts as the sugar-responsive, incretin-like hormone in the fruit fly, Drosophila melanogaster. Secreted NPF is received by NPF receptor in the corpora cardiaca and in insulin-producing cells. NPF-NPFR signalling resulted in the suppression of the glucagon-like hormone production and the enhancement of the insulin-like peptide secretion, eventually promoting lipid anabolism. Similar to the loss of incretin function in mammals, loss of midgut NPF led to significant metabolic dysfunction, accompanied by lipodystrophy, hyperphagia, and hypoglycaemia. These results suggest that enteroendocrine hormones regulate sugar-dependent metabolism through glucagon-like and insulin-like hormones not only in mammals but also in insects.


Assuntos
Drosophila melanogaster/metabolismo , Células Enteroendócrinas/metabolismo , Glucagon/metabolismo , Hormônios/metabolismo , Insulina/metabolismo , Neuropeptídeos/metabolismo , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Hipoglicemia/genética , Hipoglicemia/metabolismo , Incretinas/metabolismo , Secreção de Insulina , Metabolismo dos Lipídeos/genética , Mutação , Neuropeptídeos/genética , Receptores de Neuropeptídeos/genética , Receptores de Neuropeptídeos/metabolismo , Açúcares/metabolismo
4.
Nat Commun ; 12(1): 4258, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253734

RESUMO

The maintenance of constant karyoplasmic ratios suggests that nuclear size has physiological significance. Nuclear size anomalies have been linked to malignant transformation, although the mechanism remains unclear. By expressing dominant-negative TER94 mutants in Drosophila photoreceptors, here we show disruption of VCP (valosin-containing protein, human TER94 ortholog), a ubiquitin-dependent segregase, causes progressive nuclear size increase. Loss of VCP function leads to accumulations of MDC1 (mediator of DNA damage checkpoint protein 1), connecting DNA damage or associated responses to enlarged nuclei. TER94 can interact with MDC1 and decreases MDC1 levels, suggesting that MDC1 is a VCP substrate. Our evidence indicates that MDC1 accumulation stabilizes p53A, leading to TER94K2A-associated nuclear size increase. Together with a previous report that p53A disrupts autophagic flux, we propose that the stabilization of p53A in TER94K2A-expressing cells likely hinders the removal of nuclear content, resulting in aberrant nuclear size increase.


Assuntos
Autofagia , Tamanho do Núcleo Celular , Núcleo Celular/metabolismo , Dano ao DNA , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína com Valosina/metabolismo , Animais , Biomarcadores/metabolismo , Olho Composto de Artrópodes , Reparo do DNA , Mitose , Transdução de Sinais , Fatores de Tempo , Proteínas Ubiquitinadas/metabolismo
5.
Nat Commun ; 12(1): 4527, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312384

RESUMO

Optogenetic manipulation of neuronal activity through excitatory and inhibitory opsins has become an indispensable experimental strategy in neuroscience research. For many applications bidirectional control of neuronal activity allowing both excitation and inhibition of the same neurons in a single experiment is desired. This requires low spectral overlap between the excitatory and inhibitory opsin, matched photocurrent amplitudes and a fixed expression ratio. Moreover, independent activation of two distinct neuronal populations with different optogenetic actuators is still challenging due to blue-light sensitivity of all opsins. Here we report BiPOLES, an optogenetic tool for potent neuronal excitation and inhibition with light of two different wavelengths. BiPOLES enables sensitive, reliable dual-color neuronal spiking and silencing with single- or two-photon excitation, optical tuning of the membrane voltage, and independent optogenetic control of two neuronal populations using a second, blue-light sensitive opsin. The utility of BiPOLES is demonstrated in worms, flies, mice and ferrets.


Assuntos
Membrana Celular/fisiologia , Opsinas/metabolismo , Optogenética/métodos , Células Piramidais/fisiologia , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Células Cultivadas , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Furões/genética , Furões/metabolismo , Células HEK293 , Hipocampo/citologia , Humanos , Masculino , Potenciais da Membrana/fisiologia , Camundongos Transgênicos , Opsinas/genética , Técnicas de Patch-Clamp/métodos , Células Piramidais/citologia , Células Piramidais/metabolismo , Ratos Wistar , Reprodutibilidade dos Testes
6.
Am J Hum Genet ; 108(9): 1669-1691, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34314705

RESUMO

Transportin-2 (TNPO2) mediates multiple pathways including non-classical nucleocytoplasmic shuttling of >60 cargoes, such as developmental and neuronal proteins. We identified 15 individuals carrying de novo coding variants in TNPO2 who presented with global developmental delay (GDD), dysmorphic features, ophthalmologic abnormalities, and neurological features. To assess the nature of these variants, functional studies were performed in Drosophila. We found that fly dTnpo (orthologous to TNPO2) is expressed in a subset of neurons. dTnpo is critical for neuronal maintenance and function as downregulating dTnpo in mature neurons using RNAi disrupts neuronal activity and survival. Altering the activity and expression of dTnpo using mutant alleles or RNAi causes developmental defects, including eye and wing deformities and lethality. These effects are dosage dependent as more severe phenotypes are associated with stronger dTnpo loss. Interestingly, similar phenotypes are observed with dTnpo upregulation and ectopic expression of TNPO2, showing that loss and gain of Transportin activity causes developmental defects. Further, proband-associated variants can cause more or less severe developmental abnormalities compared to wild-type TNPO2 when ectopically expressed. The impact of the variants tested seems to correlate with their position within the protein. Specifically, those that fall within the RAN binding domain cause more severe toxicity and those in the acidic loop are less toxic. Variants within the cargo binding domain show tissue-dependent effects. In summary, dTnpo is an essential gene in flies during development and in neurons. Further, proband-associated de novo variants within TNPO2 disrupt the function of the encoded protein. Hence, TNPO2 variants are causative for neurodevelopmental abnormalities.


Assuntos
Deficiências do Desenvolvimento/genética , Proteínas de Drosophila/genética , Oftalmopatias Hereditárias/genética , Deficiência Intelectual/genética , Carioferinas/genética , Anormalidades Musculoesqueléticas/genética , beta Carioferinas/genética , Proteína ran de Ligação ao GTP/genética , Alelos , Sequência de Aminoácidos , Animais , Deficiências do Desenvolvimento/metabolismo , Deficiências do Desenvolvimento/patologia , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Oftalmopatias Hereditárias/metabolismo , Oftalmopatias Hereditárias/patologia , Feminino , Dosagem de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genoma Humano , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/metabolismo , Deficiência Intelectual/patologia , Carioferinas/antagonistas & inibidores , Carioferinas/metabolismo , Masculino , Anormalidades Musculoesqueléticas/metabolismo , Anormalidades Musculoesqueléticas/patologia , Mutação , Neurônios/metabolismo , Neurônios/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sequenciamento Completo do Genoma , beta Carioferinas/metabolismo , Proteína ran de Ligação ao GTP/metabolismo
7.
Nat Commun ; 12(1): 4504, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301936

RESUMO

Genes are expressed in stochastic transcriptional bursts linked to alternating active and inactive promoter states. A major challenge in transcription is understanding how promoter composition dictates bursting, particularly in multicellular organisms. We investigate two key Drosophila developmental promoter motifs, the TATA box (TATA) and the Initiator (INR). Using live imaging in Drosophila embryos and new computational methods, we demonstrate that bursting occurs on multiple timescales ranging from seconds to minutes. TATA-containing promoters and INR-containing promoters exhibit distinct dynamics, with one or two separate rate-limiting steps respectively. A TATA box is associated with long active states, high rates of polymerase initiation, and short-lived, infrequent inactive states. In contrast, the INR motif leads to two inactive states, one of which relates to promoter-proximal polymerase pausing. Surprisingly, the model suggests pausing is not obligatory, but occurs stochastically for a subset of polymerases. Overall, our results provide a rationale for promoter switching during zygotic genome activation.


Assuntos
Drosophila melanogaster/genética , Embrião não Mamífero/metabolismo , Regiões Promotoras Genéticas/genética , TATA Box/genética , Imagem com Lapso de Tempo/métodos , Transcrição Genética/genética , Algoritmos , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/embriologia , Drosophila melanogaster/metabolismo , Embrião não Mamífero/embriologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Cinética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Modelos Teóricos
8.
Nat Commun ; 12(1): 4595, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321459

RESUMO

Constriction of the cytokinetic ring, a circular structure of actin filaments, is an essential step during cell division. Mechanical forces driving the constriction are attributed to myosin motor proteins, which slide actin filaments along each other. However, in multiple organisms, ring constriction has been reported to be myosin independent. How actin rings constrict in the absence of motor activity remains unclear. Here, we demonstrate that anillin, a non-motor actin crosslinker, indispensable during cytokinesis, autonomously propels the contractility of actin bundles. Anillin generates contractile forces of tens of pico-Newtons to maximise the lengths of overlaps between bundled actin filaments. The contractility is enhanced by actin disassembly. When multiple actin filaments are arranged into a ring, this contractility leads to ring constriction. Our results indicate that passive actin crosslinkers can substitute for the activity of molecular motors to generate contractile forces in a variety of actin networks, including the cytokinetic ring.


Assuntos
Actinas/metabolismo , Proteínas Contráteis/metabolismo , Miosinas/metabolismo , Citoesqueleto de Actina/metabolismo , Actomiosina/metabolismo , Animais , Divisão Celular , Proteínas Contráteis/genética , Citocinese , Drosophila melanogaster/metabolismo , Humanos , Proteínas dos Microfilamentos
9.
Nat Commun ; 12(1): 4131, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226544

RESUMO

Feeding decisions are fundamental to survival, and decision making is often disrupted in disease. Here, we show that neural activity in a small population of neurons projecting to the fan-shaped body higher-order central brain region of Drosophila represents food choice during sensory conflict. We found that food deprived flies made tradeoffs between appetitive and aversive values of food. We identified an upstream neuropeptidergic and dopaminergic network that relays internal state and other decision-relevant information to a specific subset of fan-shaped body neurons. These neurons were strongly inhibited by the taste of the rejected food choice, suggesting that they encode behavioral food choice. Our findings reveal that fan-shaped body taste responses to food choices are determined not only by taste quality, but also by previous experience (including choice outcome) and hunger state, which are integrated in the fan-shaped body to encode the decision before relay to downstream motor circuits for behavioral implementation.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila/metabolismo , Neurônios/metabolismo , Animais , Encéfalo/metabolismo , Tomada de Decisões , Comportamento Alimentar/fisiologia , Preferências Alimentares , Fome/fisiologia , Paladar/fisiologia , Percepção Gustatória
10.
Nature ; 596(7870): 97-102, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34290404

RESUMO

Infection-induced aversion against enteropathogens is a conserved sickness behaviour that can promote host survival1,2. The aetiology of this behaviour remains poorly understood, but studies in Drosophila have linked olfactory and gustatory perception to avoidance behaviours against toxic microorganisms3-5. Whether and how enteric infections directly influence sensory perception to induce or modulate such behaviours remains unknown. Here we show that enteropathogen infection in Drosophila can modulate olfaction through metabolic reprogramming of ensheathing glia of the antennal lobe. Infection-induced unpaired cytokine expression in the intestine activates JAK-STAT signalling in ensheathing glia, inducing the expression of glial monocarboxylate transporters and the apolipoprotein glial lazarillo (GLaz), and affecting metabolic coupling of glia and neurons at the antennal lobe. This modulates olfactory discrimination, promotes the avoidance of bacteria-laced food and increases fly survival. Although transient in young flies, gut-induced metabolic reprogramming of ensheathing glia becomes constitutive in old flies owing to age-related intestinal inflammation, which contributes to an age-related decline in olfactory discrimination. Our findings identify adaptive glial metabolic reprogramming by gut-derived cytokines as a mechanism that causes lasting changes in a sensory system in ageing flies.


Assuntos
Envelhecimento/metabolismo , Citocinas/metabolismo , Drosophila melanogaster/metabolismo , Intestinos , Neuroglia/metabolismo , Olfato/fisiologia , Animais , Aprendizagem da Esquiva , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/microbiologia , Feminino , Inflamação/metabolismo , Inflamação/microbiologia , Intestinos/microbiologia , Janus Quinases/metabolismo , Ácido Láctico/metabolismo , Metabolismo dos Lipídeos , Neurônios/metabolismo , Pectobacterium carotovorum , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Taxa de Sobrevida , Fatores de Transcrição/metabolismo
11.
Aging (Albany NY) ; 13(11): 14709-14728, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074800

RESUMO

One of the genes which has been linked to the onset of juvenile/early onset Parkinson's disease (PD) is PINK1. There is evidence that supports the therapeutic potential of exercise in the alleviation of PD symptoms. It is possible that exercise may enhance synaptic plasticity, protect against neuro-inflammation and modulate L-Dopa regulated signalling pathways. We explored the effects of exercise on Pink1 deficient Drosophila melanogaster which undergo neurodegeneration and muscle degeneration. We used a 'power-tower' type exercise platform to deliver exercise activity to Pink1- and age matched wild-type Drosophila. Mitochondrial proteomic profiles responding to exercise were obtained. Of the 516 proteins identified, 105 proteins had different levels between Pink1- and wild-type non-exercised Drosophila. Gene ontology enrichment analysis and STRING network analysis highlighted proteins and pathways with altered expression within the mitochondrial proteome. Comparison of the Pink1- exercised proteome to wild-type proteomes showed that exercising the Pink1- Drosophila caused their proteomic profile to return towards wild-type levels.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas Mitocondriais/metabolismo , Condicionamento Físico Animal , Proteínas Serina-Treonina Quinases/metabolismo , Proteoma/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Eletroforese em Gel Bidimensional , Metabolismo Energético , Regulação da Expressão Gênica , Ontologia Genética , Espectrometria de Massas , Mitocôndrias/metabolismo , Anotação de Sequência Molecular , Mutação/genética , Mapas de Interação de Proteínas , Proteínas Serina-Treonina Quinases/genética , Proteômica
12.
Methods Mol Biol ; 2275: 279-289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34118044

RESUMO

Fluorescent live imaging on Drosophila melanogaster is a microscopy technique in rapid expansion. The growing number of probes available to detect cellular components and the relatively easy genetic manipulation of fruit fly make this model one of the most used for in vivo analysis of several physiological and/or pathological processes. Here we describe the chemical synthesis of two norbormide-derived BODIPY-conjugated fluorescent probes (NRBMC009 and NRBZLW0047). Moreover, we describe the larval dissection method, and subsequent live imaging acquisition. Both probes are able to label mitochondria in different Drosophila larval tissues, which allows for the characterization of mitochondrial morphological alterations by using a simple and quick method that avoids the fixation artefacts that often occur in immunofluorescence studies.


Assuntos
Drosophila melanogaster/metabolismo , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Norbornanos/química , Animais , Larva , Microscopia Confocal , Microscopia de Fluorescência , Imagem Molecular
13.
J Proteomics ; 246: 104307, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34174476

RESUMO

Peptides present in the seminal fluid of Drosophila melanogaster can function as antimicrobial agents, enzyme inhibitors and as pheromones that elicit physiological and behavioural responses in the post-mated female. Understanding the molecular interactions by which these peptides influence reproduction requires detailed knowledge of their molecular structures. However, this information is often lacking and cannot be gleaned from just gene sequences and standard proteomic data. We now report the native structures of four seminal fluid peptides (andropin, CG42782, Met75C and Acp54A1) from the ejaculatory duct of male D. melanogaster. The mature CG42782, Met75C and Acp54A1 peptides each have a cyclic structure formed by a disulfide bond, which will reduce conformational freedom and enhance metabolic stability. In addition, the presence of a penultimate Pro in CG42782 and Met75C will help prevent degradation by carboxypeptidases. Met75C has undergone more extensive post-translational modifications with the formation of an N-terminal pyroglutamyl residue and the attachment of a mucin-like O-glycan to the side chain of Thr4. Both of these modifications are expected to further enhance the stability of the secreted peptide. The glycan has a rare zwitterionic structure comprising an O-linked N-acetyl hexosamine, a hexose and, unusually, phosphoethanolamine. A survey of various genomes showed that andropin, CG42782, and Acp54A1 are relatively recent genes and are restricted to the melanogaster subgroup. Met75C, however, was also found in members of the obscura species groups and in Scaptodrosophila lebanonensis. Andropin is related to the cecropin gene family and probably arose by tandem gene duplication, whereas CG42782, Met75C and Acp54A1 possibly emerged de novo. We speculate that the post-translational modifications that we report for these gene products will be important not only for a biological function, but also for metabolic stability and might also facilitate transport across tissue barriers, such as the blood-brain barrier of the female insect. BIOLOGICAL SIGNIFICANCE: Seminal fluid peptides of D. melanogaster function as antimicrobials, enzyme inhibitors and as pheromones, eliciting physiological and behavioural responses in the post-mated female. A fuller understanding of how these peptides influence reproduction requires knowledge not only of their primary structure, but also of their post-translational modification. However, this information is often lacking and difficult to glean from standard proteomic data. The reported modifications, including the unusual glycosylation, adds much to our knowledge of this important class of peptides in this model organism, par excellence.


Assuntos
Drosophila melanogaster , Glicopeptídeos , Animais , Drosophila melanogaster/metabolismo , Ductos Ejaculatórios/metabolismo , Feminino , Glicosilação , Masculino , Peptídeos/metabolismo , Proteômica
14.
Life Sci ; 281: 119758, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34175317

RESUMO

AIMS: The current lifestyle trend has made people vulnerable to diabetes and related diseases. Years of scientific research have not been able to yield a cure to the disease completely. The current study aims to investigate a link between high-fat diet mediated diabesity and circadian rhythm in the Drosophila model and inferences that might help in establishing a cure to the dreaded disease. MAIN METHODS: Several experimental methods including phenotypical, histological, biochemical, molecular, and behavioral assays were used in the study to detect obesity, diabetes, and changes in the circadian clock in the fly model. KEY FINDINGS: The larva and adults of Drosophila melanogaster exposed to high-fat diet (HFD) displayed excess deposition of fat as lipid droplets and micronuclei formation in the gut, fat body, and crop. Larva and adults of HFD showed behavioral defects. The higher amount of triglyceride, glucose, trehalose in the whole body of larva and adult fly confirmed obesity-induced hyperglycemia. The overexpression of insulin gene (Dilp2) and tribble (trbl) gene expression confirmed insulin resistance in HFD adults. We also observed elevated ROS level, developmental delay, altered metal level, growth defects, locomotory rhythms, sleep fragmentation, and expression of circadian genes (per, tim, and clock) in HFD larva and adults. Thus, HFD impairs the metabolism to produce obesity, insulin resistance, disruption of clock, and circadian clock related co-mordities in D. melanogaster. SIGNIFICANCE: The circadian gene expression provides an innovative perspective to understand and find a new treatment for type-II diabetes and circadian anomalies.


Assuntos
Comportamento Animal , Relógios Circadianos , Dieta Hiperlipídica , Drosophila melanogaster/fisiologia , Tecido Adiposo/metabolismo , Animais , Relógios Circadianos/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Glucose/metabolismo , Hiperglicemia/metabolismo , Resistência à Insulina , Larva/metabolismo , Masculino , Metais/metabolismo , Obesidade/etnologia , Estresse Oxidativo , Distribuição Tecidual , Trealose/metabolismo
15.
Insect Biochem Mol Biol ; 135: 103609, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34146686

RESUMO

Insulin-like peptides (ILPs) and components of the insulin signaling pathway are conserved across different animal phyla. Eight ILPs (called DILPs) and two receptors, dInR and Lgr3, have been described in Drosophila. DILPs regulate varied physiological traits including lifespan, reproduction, development, feeding behavior, stress resistance and metabolism. At the same time, different conditions such as nutrition, dietary supplements and environmental factors affect the expression of DILPs. This review focuses primarily on DILP2, DILP3, and DILP5 which are produced by insulin-producing cells in the brain of Drosophila. Although they are produced by the same cells and can potentially compensate for each other, DILP2, DILP3, and DILP5 expression may be differentially regulated at the mRNA level. Thus, we summarized available data on the conditions affecting the expression profiles of these DILPs in adult Drosophila. The accumulated data indicate that transcript levels of DILPs are determined by (a) nutritional conditions such as the protein-to-carbohydrate ratio, (b) carbohydrate type within the diet, (c) malnutrition or complete starvation; (d) environmental factors such as stress or temperature; (e) mutations of single peptides that induce changes in the expression of the other peptides; and (f) dietary supplements of drugs or natural substances. Furthermore, manipulation of specific genes in a cell- and tissue-specific manner affects mRNA levels for DILPs and, thereby, modulates various physiological traits and metabolism in Drosophila.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Peptídeos e Proteínas de Sinalização Intercelular , Receptores Proteína Tirosina Quinases , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Comportamento Alimentar , Regulação da Expressão Gênica , Insulina/genética , Insulina/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Longevidade , Mutação , Fenótipo , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Reprodução , Transdução de Sinais
16.
Insect Biochem Mol Biol ; 136: 103611, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34182107

RESUMO

The Drosophila melanogaster corpus allatum (CA) produces and releases three types of sesquiterpenoid hormones, including juvenile hormone III bisepoxide (JHB3), juvenile hormone III (JH III), and methyl farnesoate (MF). JH biosynthesis involves multiple discrete enzymatic reactions and is subjected to a comprehensive regulatory network including microRNAs (miRNAs). Using a high throughput sequencing approach, we have identified abundant miRNAs in the D. melanogaster ring gland, which consists of the CA, prothoracic gland, and corpus cardiaca. Genetic and qPCR screens were then performed in an attempt to uncover the full repertoire of CA miRNAs that are involved in regulating metamorphosis. miR-8 was identified as a potential candidate and further studied for its role in the CA. Overexpression of miR-8 in the CA increased cell size of the gland and expression of Jhamt (a gene coding for a key regulatory enzyme in JH biosynthesis), resulting in pupal lethality. By contrast, sponge-mediated reduction of miR-8 in the CA decreased cell size and Jhamt expression, but did not cause lethality. Further investigation revealed that miR-8 promotes cell growth independent of insulin/IGF signaling. Taken together, these experiments show that miR-8 is highly expressed in the CA and exerts its positive effects on cell growth and JH biosynthesis. The miRNAs data in the ring gland also provide a useful resource to study how miRNAs collaboratively regulate hormone synthesis in D. melanogaster.


Assuntos
Corpora Allata/metabolismo , Drosophila melanogaster , Hormônios Juvenis/biossíntese , MicroRNAs , Animais , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Genes de Insetos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Insulina/metabolismo , Metamorfose Biológica/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Pupa/genética , Pupa/metabolismo , Transdução de Sinais
17.
Development ; 148(11)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34124762

RESUMO

During development, gene expression regulates cell mechanics and shape to sculpt tissues. Epithelial folding proceeds through distinct cell shape changes that occur simultaneously in different regions of a tissue. Here, using quantitative imaging in Drosophila melanogaster, we investigate how patterned cell shape changes promote tissue bending during early embryogenesis. We find that the transcription factors Twist and Snail combinatorially regulate a multicellular pattern of lateral F-actin density that differs from the previously described Myosin-2 gradient. This F-actin pattern correlates with whether cells apically constrict, stretch or maintain their shape. We show that the Myosin-2 gradient and F-actin depletion do not depend on force transmission, suggesting that transcriptional activity is required to create these patterns. The Myosin-2 gradient width results from a gradient in RhoA activation that is refined through the balance between RhoGEF2 and the RhoGAP C-GAP. Our experimental results and simulations of a 3D elastic shell model show that tuning gradient width regulates tissue curvature.


Assuntos
Actinas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Citoesqueleto de Actina/metabolismo , Actomiosina , Animais , Proteínas de Ciclo Celular , Forma Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Ativadoras de GTPase/metabolismo , Morfogênese/fisiologia , Miosina Tipo II/metabolismo , Proteínas rho de Ligação ao GTP/genética
18.
Nat Commun ; 12(1): 3730, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140480

RESUMO

Acid taste, evoked mainly by protons (H+), is a core taste modality for many organisms. The hedonic valence of acid taste is bidirectional: animals prefer slightly but avoid highly acidic foods. However, how animals discriminate low from high acidity remains poorly understood. To explore the taste perception of acid, we use the fruit fly as a model organism. We find that flies employ two competing taste sensory pathways to detect low and high acidity, and the relative degree of activation of each determines either attractive or aversive responses. Moreover, we establish one member of the fly Otopetrin family, Otopetrin-like a (OtopLa), as a proton channel dedicated to the gustatory detection of acid. OtopLa defines a unique subset of gustatory receptor neurons and is selectively required for attractive rather than aversive taste responses. Loss of otopla causes flies to reject normally attractive low-acid foods. Therefore, the identification of OtopLa as a low-acid sensor firmly supports our competition model of acid taste sensation. Altogether, we have discovered a binary acid-sensing mechanism that may be evolutionarily conserved between insects and mammals.


Assuntos
Ácidos/metabolismo , Vias Aferentes/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Neurônios/metabolismo , Vias Aferentes/fisiologia , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Eletrofisiologia , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Imuno-Histoquímica , Malatos/metabolismo , Microscopia Confocal , Mutação , Neurônios/fisiologia , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes , Paladar/fisiologia , Percepção Gustatória/fisiologia
19.
Methods Mol Biol ; 2326: 327-337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097280

RESUMO

Trace metal elements, such as zinc, iron, copper, and manganese, play catalytic or structural roles in many enzymes and numerous proteins, and accordingly, contribute to a variety of fundamental biological processes. During the past decade, the fruit fly (Drosophila melanogaster) has become an important model organism for elucidating metal homeostasis in metazoan. We have been using Drosophila as a model to study metal metabolism for many years and have optimized simple and robust assays for determining the metal content in Drosophila, such as inductively coupled plasma mass spectrometry (ICP-MS), the activity assay of enzymes dependent on metals, and staining metal ions in tissues of Drosophila. In this chapter, we present the step-by-step detailed methods for detecting the metal content in Drosophila melanogaster during metal toxicity study.


Assuntos
Drosophila melanogaster/química , Metais/análise , Animais , Colorimetria/métodos , Drosophila melanogaster/enzimologia , Drosophila melanogaster/metabolismo , Ensaios Enzimáticos/métodos , Espectrometria de Massas/métodos , Metais/metabolismo , Metais/toxicidade , Oligoelementos/análise , Oligoelementos/metabolismo , Oligoelementos/toxicidade
20.
Nat Commun ; 12(1): 3291, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078905

RESUMO

The formation of hyperphosphorylated intracellular Tau tangles in the brain is a hallmark of Alzheimer's disease (AD). Tau hyperphosphorylation destabilizes microtubules, promoting neurodegeneration in AD patients. To identify suppressors of tau-mediated AD, we perform a screen using a microRNA (miR) library in Drosophila and identify the miR-9 family as suppressors of human tau overexpression phenotypes. CG11070, a miR-9a target gene, and its mammalian orthologue UBE4B, an E3/E4 ubiquitin ligase, alleviate eye neurodegeneration, synaptic bouton defects, and crawling phenotypes in Drosophila human tau overexpression models. Total and phosphorylated Tau levels also decrease upon CG11070 or UBE4B overexpression. In mammalian neuroblastoma cells, overexpression of UBE4B and STUB1, which encodes the E3 ligase CHIP, increases the ubiquitination and degradation of Tau. In the Tau-BiFC mouse model, UBE4B and STUB1 overexpression also increase oligomeric Tau degradation. Inhibitor assays of the autophagy and proteasome systems reveal that the autophagy-lysosome system is the major pathway for Tau degradation in this context. These results demonstrate that UBE4B, a miR-9 target gene, promotes autophagy-mediated Tau degradation together with STUB1, and is thus an innovative therapeutic approach for AD.


Assuntos
Doença de Alzheimer/genética , Proteínas de Drosophila/genética , MicroRNAs/genética , Ubiquitina-Proteína Ligases/genética , Proteínas tau/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Autofagia/genética , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Olho/metabolismo , Olho/patologia , Humanos , Lisossomos/metabolismo , Camundongos , MicroRNAs/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Proteínas tau/metabolismo
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