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1.
Elife ; 102021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596529

RESUMO

In multiple cell lineages, Delta-Notch signalling regulates cell fate decisions owing to unidirectional signalling between daughter cells. In Drosophila pupal sensory organ lineage, Notch regulates the intra-lineage pIIa/pIIb fate decision at cytokinesis. Notch and Delta that localise apically and basally at the pIIa-pIIb interface are expressed at low levels and their residence time at the plasma membrane is in the order of minutes. How Delta can effectively interact with Notch to trigger signalling from a large plasma membrane area remains poorly understood. Here, we report that the signalling interface possesses a unique apico-basal polarity with Par3/Bazooka localising in the form of nano-clusters at the apical and basal level. Notch is preferentially targeted to the pIIa-pIIb interface, where it co-clusters with Bazooka and its cofactor Sanpodo. Clusters whose assembly relies on Bazooka and Sanpodo activities are also positive for Neuralized, the E3 ligase required for Delta activity. We propose that the nano-clusters act as snap buttons at the new pIIa-pIIb interface to allow efficient intra-lineage signalling.


Assuntos
Divisão Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Receptores Notch/metabolismo , Órgãos dos Sentidos/metabolismo , Células-Tronco/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem da Célula , Polaridade Celular , Citocinese , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Receptores Notch/genética , Órgãos dos Sentidos/citologia , Transdução de Sinais , Fatores de Tempo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
Int J Mol Sci ; 22(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34638607

RESUMO

Asymmetric cell division (ACD) of neural stem cells and progenitors not only renews the stem cell population but also ensures the normal development of the nervous system, producing various types of neurons with different shapes and functions in the brain. One major mechanism to achieve ACD is the asymmetric localization and uneven segregation of intracellular proteins and organelles into sibling cells. Recent studies have demonstrated that liquid-liquid phase separation (LLPS) provides a potential mechanism for the formation of membrane-less biomolecular condensates that are asymmetrically distributed on limited membrane regions. Moreover, mechanical forces have emerged as pivotal regulators of asymmetric neural stem cell division by generating sibling cell size asymmetry. In this review, we will summarize recent discoveries of ACD mechanisms driven by LLPS and mechanical forces.


Assuntos
Divisão Celular Assimétrica/fisiologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Animais , Fenômenos Biomecânicos , Divisão Celular/fisiologia , Polaridade Celular/fisiologia , Tamanho Celular , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/fisiologia , Modelos Neurológicos , Miosinas/fisiologia , Neurogênese/fisiologia , Organelas/fisiologia
3.
Nat Commun ; 12(1): 5633, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561451

RESUMO

The brain plays a key role in energy homeostasis, detecting nutrients, metabolites and circulating hormones from peripheral organs and integrating this information to control food intake and energy expenditure. Here, we show that a group of neurons in the Drosophila larval brain expresses the adiponectin receptor (AdipoR) and controls systemic growth and metabolism through insulin signaling. We identify glucose-regulated protein 78 (Grp78) as a circulating antagonist of AdipoR function produced by fat cells in response to dietary sugar. We further show that central AdipoR signaling inhibits peripheral Juvenile Hormone (JH) response, promoting insulin signaling. In conclusion, we identify a neuroendocrine axis whereby AdipoR-positive neurons control systemic insulin response.


Assuntos
Encéfalo/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Insulina/metabolismo , Neurônios/metabolismo , Receptores de Adiponectina/metabolismo , Animais , Animais Geneticamente Modificados , Encéfalo/citologia , Linhagem Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Metabolismo Energético/genética , Hemolinfa/metabolismo , Homeostase , Hormônios Juvenis/metabolismo , Larva/genética , Larva/metabolismo , Receptores de Adiponectina/genética , Transdução de Sinais/genética
4.
Nat Commun ; 12(1): 5488, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531401

RESUMO

Specialised ribonucleoprotein (RNP) granules are a hallmark of polarized cells, like neurons and germ cells. Among their main functions is the spatial and temporal modulation of the activity of specific mRNA transcripts that allow specification of primary embryonic axes. While RNPs composition and role are well established, their regulation is poorly defined. Here, we demonstrate that Hecw, a newly identified Drosophila ubiquitin ligase, is a key modulator of RNPs in oogenesis and neurons. Hecw depletion leads to the formation of enlarged granules that transition from a liquid to a gel-like state. Loss of Hecw activity results in defective oogenesis, premature aging and climbing defects associated with neuronal loss. At the molecular level, reduced ubiquitination of the Fmrp impairs its translational repressor activity, resulting in altered Orb expression in nurse cells and Profilin in neurons.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Neurogênese/genética , Oogênese/genética , Ribonucleoproteínas/genética , Ubiquitina-Proteína Ligases/genética , Animais , Grânulos Citoplasmáticos/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Embrião não Mamífero , Proteína do X Frágil de Retardo Mental/genética , Proteína do X Frágil de Retardo Mental/metabolismo , Homeostase/genética , Longevidade/genética , Neurônios/citologia , Neurônios/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Transição de Fase , Profilinas/genética , Profilinas/metabolismo , Biossíntese de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
5.
Sci Rep ; 11(1): 17958, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504130

RESUMO

Several plant lectins, or carbohydrate-binding proteins, interact with glycan moieties on the surface of immune cells, thereby influencing the immune response of these cells. Orysata, a mannose-binding lectin from rice, has been reported to exert immunomodulatory activities on insect cells. While the natural lectin is non-glycosylated, recombinant Orysata produced in the yeast Pichia pastoris (YOry) is modified with a hyper-mannosylated N-glycan. Since it is unclear whether this glycosylation can affect the YOry activity, non-glycosylated rOrysata was produced in Escherichia coli (BOry). In a comparative analysis, both recombinant Orysata proteins were tested for their carbohydrate specificity on a glycan array, followed by the investigation of the carbohydrate-dependent agglutination of red blood cells (RBCs) and the carbohydrate-independent immune responses in Drosophila melanogaster S2 cells. Although YOry and BOry showed a similar carbohydrate-binding profiles, lower concentration of BOry were sufficient for the agglutination of RBCs and BOry induced stronger immune responses in S2 cells. The data are discussed in relation to different hypotheses explaining the weaker responses of glycosylated YOry. In conclusion, these observations contribute to the understanding how post-translational modification can affect protein function, and provide guidance in the selection of the proper expression system for the recombinant production of lectins.


Assuntos
Drosophila melanogaster/citologia , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Lectinas de Ligação a Manose/metabolismo , Lectinas de Ligação a Manose/farmacologia , Oryza/química , Fagócitos/efeitos dos fármacos , Fagócitos/imunologia , Lectinas de Plantas/metabolismo , Lectinas de Plantas/farmacologia , Polissacarídeos/metabolismo , Animais , Linhagem Celular , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosilação , Hemaglutinação/efeitos dos fármacos , Lectinas de Ligação a Manose/genética , Fagócitos/metabolismo , Lectinas de Plantas/genética , Ligação Proteica , Coelhos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Saccharomycetales/genética , Saccharomycetales/metabolismo
6.
J Insect Physiol ; 134: 104309, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34496279

RESUMO

The adult Drosophila intestinal epithelium must be tightly regulated to maintain regeneration and homeostasis. The dysregulation of the regenerative capacity is frequently associated with intestinal diseases such as inflammation and tumorigenesis. Here, we showed that the G protein-coupled receptor Anchor maintains Drosophila adult midgut homeostasis by restricting Jun-N-terminal kinase (JNK) and Notch pathway activity. anchor inactivation resulted in aberrant JNK pathway activation, which led to excessive enteroblast (EB) production and premature enterocyte (EC) differentiation. In addition, increased Notch levels promoted premature EC differentiation following the loss of anchor. This defect induced by the loss of anchor ultimately caused sensitivity to stress or environmental challenge in adult flies. Taken together, our results demonstrate that the activity of anchor is essential to coordinate stem cell differentiation and proliferation to maintain intestinal homeostasis.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Homeostase/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Proliferação de Células , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Enterócitos , Trato Gastrointestinal/citologia , Trato Gastrointestinal/metabolismo , Sistema de Sinalização das MAP Quinases , Receptores Notch/metabolismo , Transdução de Sinais
7.
Nature ; 597(7875): 239-244, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34408325

RESUMO

Social isolation and loneliness have potent effects on public health1-4. Research in social psychology suggests that compromised sleep quality is a key factor that links persistent loneliness to adverse health conditions5,6. Although experimental manipulations have been widely applied to studying the control of sleep and wakefulness in animal models, how normal sleep is perturbed by social isolation is unknown. Here we report that chronic, but not acute, social isolation reduces sleep in Drosophila. We use quantitative behavioural analysis and transcriptome profiling to differentiate between brain states associated with acute and chronic social isolation. Although the flies had uninterrupted access to food, chronic social isolation altered the expression of metabolic genes and induced a brain state that signals starvation. Chronically isolated animals exhibit sleep loss accompanied by overconsumption of food, which resonates with anecdotal findings of loneliness-associated hyperphagia in humans. Chronic social isolation reduces sleep and promotes feeding through neural activities in the peptidergic fan-shaped body columnar neurons of the fly. Artificial activation of these neurons causes misperception of acute social isolation as chronic social isolation and thereby results in sleep loss and increased feeding. These results present a mechanistic link between chronic social isolation, metabolism, and sleep, addressing a long-standing call for animal models focused on loneliness7.


Assuntos
Encéfalo/metabolismo , Drosophila melanogaster/metabolismo , Comportamento Alimentar , Modelos Animais , Sono , Isolamento Social , Inanição/metabolismo , Animais , Encéfalo/citologia , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Fome , Hiperfagia/genética , Solidão , Masculino , Neurônios/metabolismo , Sono/genética , Privação do Sono/genética , Privação do Sono/metabolismo , Inanição/genética , Fatores de Tempo , Transcriptoma
8.
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
9.
PLoS Biol ; 19(8): e3001367, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34379617

RESUMO

Damage in the nervous system induces a stereotypical response that is mediated by glial cells. Here, we use the eye disc of Drosophila melanogaster as a model to explore the mechanisms involved in promoting glial cell response after neuronal cell death induction. We demonstrate that these cells rapidly respond to neuronal apoptosis by increasing in number and undergoing morphological changes, which will ultimately grant them phagocytic abilities. We found that this glial response is controlled by the activity of Decapentaplegic (Dpp) and Hedgehog (Hh) signalling pathways. These pathways are activated after cell death induction, and their functions are necessary to induce glial cell proliferation and migration to the eye discs. The latter of these 2 processes depend on the function of the c-Jun N-terminal kinase (JNK) pathway, which is activated by Dpp signalling. We also present evidence that a similar mechanism controls glial response upon apoptosis induction in the leg discs, suggesting that our results uncover a mechanism that might be involved in controlling glial cells response to neuronal cell death in different regions of the peripheral nervous system (PNS).


Assuntos
Olho Composto de Artrópodes/crescimento & desenvolvimento , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/crescimento & desenvolvimento , Proteínas Hedgehog/fisiologia , Neuroglia/fisiologia , Animais , Apoptose , Movimento Celular , Olho Composto de Artrópodes/citologia , Drosophila melanogaster/citologia , Sistema de Sinalização das MAP Quinases
10.
PLoS One ; 16(7): e0246224, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34228751

RESUMO

Chloride intracellular channels (CLICs) are a unique family of evolutionarily conserved metamorphic proteins, switching between stable conformations based on redox conditions. CLICs have been implicated in a wide variety biological processes including ion channel activity, apoptosis, membrane trafficking, and enzymatic oxidoreductase activity. Understanding the molecular mechanisms by which CLICs engage in these activities is an area of active research. Here, the sole Drosophila melanogaster ortholog, Clic, was targeted for RNAi knockdown to identify genes and biological processes associated with Clic expression. Clic knockdown had a substantial impact on global transcription, altering expression of over 7% of transcribed Drosophila genes. Overrepresentation analysis of differentially expressed genes identified enrichment of Gene Ontology terms including Cytoplasmic Translation, Oxidation-Reduction Process, Heme Binding, Membrane, Cell Junction, and Nucleolus. The top term, Cytoplasmic Translation, was enriched almost exclusively with downregulated genes. Drosophila Clic and vertebrate ortholog Clic4 have previously been tied to ethanol sensitivity and ethanol-regulated expression. Clic knockdown-responsive genes from the present study were found to overlap significantly with gene sets from 4 independently published studies related to ethanol exposure and sensitivity in Drosophila. Bioinformatic analysis of genes shared between these studies revealed an enrichment of genes related to amino acid metabolism, protein processing, oxidation-reduction processes, and lipid particles among others. To determine whether the modulation of ethanol sensitivity by Clic may be related to co-regulated oxidation-reduction processes, we evaluated the effect of hyperoxia on ethanol sedation in Clic knockdown flies. Consistent with previous findings, Clic knockdown reduced acute ethanol sedation sensitivity in flies housed under normoxia. However, this effect was reversed by exposure to hyperoxia, suggesting a common set of molecular-genetic mechanism may modulate each of these processes. This study suggests that Drosophila Clic has a major influence on regulation of oxidative stress signaling and that this function overlaps with the molecular mechanisms of acute ethanol sensitivity in the fly.


Assuntos
Canais de Cloreto/deficiência , Canais de Cloreto/genética , Cloretos/metabolismo , Drosophila melanogaster/citologia , Etanol/farmacologia , Perfilação da Expressão Gênica , Espaço Intracelular/metabolismo , Animais , Drosophila melanogaster/metabolismo , Técnicas de Silenciamento de Genes , Espaço Intracelular/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
11.
PLoS Genet ; 17(6): e1009655, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34181646

RESUMO

During spermatogenesis, the process in which sperm for fertilization are produced from germline cells, gene expression is spatiotemporally highly regulated. In Drosophila, successful expression of extremely large male fertility factor genes on Y-chromosome spanning some megabases due to their gigantic intron sizes is crucial for spermatogenesis. Expression of such extremely large genes must be challenging, but the molecular mechanism that allows it remains unknown. Here we report that a novel RNA-binding protein Maca, which contains two RNA-recognition motifs, is crucial for this process. maca null mutant male flies exhibited a failure in the spermatid individualization process during spermatogenesis, lacked mature sperm, and were completely sterile, while maca mutant female flies were fully fertile. Proteomics and transcriptome analyses revealed that both protein and mRNA abundance of the gigantic male fertility factor genes kl-2, kl-3, and kl-5 (kl genes) are significantly decreased, where the decreases of kl-2 are particularly dramatic, in maca mutant testes. Splicing of the kl-3 transcripts was also dysregulated in maca mutant testes. All these physiological and molecular phenotypes were rescued by a maca transgene in the maca mutant background. Furthermore, we found that in the control genetic background, Maca is exclusively expressed in spermatocytes in testes and enriched at Y-loop A/C in the nucleus, where the kl-5 primary transcripts are localized. Our data suggest that Maca increases transcription processivity, promotes successful splicing of gigantic introns, and/or protects transcripts from premature degradation, of the kl genes. Our study identified a novel RNA-binding protein Maca that is crucial for successful expression of the gigantic male fertility factor genes, spermatogenesis, and male fertility.


Assuntos
Drosophila melanogaster/genética , Proteínas de Ligação a RNA/genética , Espermátides/metabolismo , Espermatócitos/metabolismo , Espermatogênese/genética , Transcriptoma , Animais , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Feminino , Fertilidade/genética , Regulação da Expressão Gênica , Ontologia Genética , Genes Reporter , Teste de Complementação Genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Masculino , Anotação de Sequência Molecular , Mutação , Proteínas de Ligação a RNA/metabolismo , Espermátides/citologia , Espermátides/crescimento & desenvolvimento , Espermatócitos/citologia , Espermatócitos/crescimento & desenvolvimento , Testículo/citologia , Testículo/metabolismo , Cromossomo Y/química
12.
PLoS Genet ; 17(5): e1009247, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34014920

RESUMO

Germline stem cells divide asymmetrically to produce one new daughter stem cell and one daughter cell that will subsequently undergo meiosis and differentiate to generate the mature gamete. The silent sister hypothesis proposes that in asymmetric divisions, the selective inheritance of sister chromatids carrying specific epigenetic marks between stem and daughter cells impacts cell fate. To facilitate this selective inheritance, the hypothesis specifically proposes that the centromeric region of each sister chromatid is distinct. In Drosophila germ line stem cells (GSCs), it has recently been shown that the centromeric histone CENP-A (called CID in flies)-the epigenetic determinant of centromere identity-is asymmetrically distributed between sister chromatids. In these cells, CID deposition occurs in G2 phase such that sister chromatids destined to end up in the stem cell harbour more CENP-A, assemble more kinetochore proteins and capture more spindle microtubules. These results suggest a potential mechanism of 'mitotic drive' that might bias chromosome segregation. Here we report that the inner kinetochore protein CENP-C, is required for the assembly of CID in G2 phase in GSCs. Moreover, CENP-C is required to maintain a normal asymmetric distribution of CID between stem and daughter cells. In addition, we find that CID is lost from centromeres in aged GSCs and that a reduction in CENP-C accelerates this loss. Finally, we show that CENP-C depletion in GSCs disrupts the balance of stem and daughter cells in the ovary, shifting GSCs toward a self-renewal tendency. Ultimately, we provide evidence that centromere assembly and maintenance via CENP-C is required to sustain asymmetric divisions in female Drosophila GSCs.


Assuntos
Proteína Centromérica A/metabolismo , Centrômero/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Epigênese Genética , Células Germinativas/metabolismo , Células-Tronco/metabolismo , Animais , Autorrenovação Celular , Senescência Celular , Proteínas Cromossômicas não Histona/deficiência , Proteínas de Drosophila/deficiência , Drosophila melanogaster/metabolismo , Feminino , Fase G2 , Masculino , Prófase , Fase S
13.
Aging (Albany NY) ; 13(11): 15013-15031, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031268

RESUMO

Fat storage is one of the important strategies employed in regulating energy homeostasis. Impaired lipid storage causes metabolic disorders in both mammals and Drosophila. In this study, we report CG9911, the Drosophila homolog of ERp44 (endoplasmic reticulum protein 44) plays a role in regulating adipose tissue fat storage. Using the CRISPR/Cas9 system, we generated a CG9911 mutant line deleting 5 bp of the coding sequence. The mutant flies exhibit phenotypes of lower bodyweight, fewer lipid droplets, reduced TAG level and increased expression of lipolysis related genes. The increased lipolysis phenotype is enhanced in the presence of ER stresses and suppressed by a reduction of the ER Ca2+. Moreover, loss of CG9911 per se results in a decrease of ER Ca2+ in the fat body. Together, our results reveal a novel function of CG9911 in promoting fat storage via regulating ER Ca2+ signal in Drosophila.


Assuntos
Adipócitos/metabolismo , Adiposidade , Cálcio/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/metabolismo , Retículo Endoplasmático/metabolismo , Homeostase , Proteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Animais , Sequência de Bases , Proteínas de Drosophila/genética , Estresse do Retículo Endoplasmático , Espaço Intracelular/metabolismo , Lipólise , Proteínas de Membrana/genética , Modelos Biológicos , Chaperonas Moleculares/genética , Mutação/genética , Fenótipo
14.
Sci Rep ; 11(1): 10644, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34017013

RESUMO

The Drosophila testis provides an exemplary model for analyzing the extrinsic and intrinsic factors that regulate the fate of stem cell in vivo. Using this model, we show that the Drosophila αTub67C gene (full name αTubulin at 67C), which encodes α4-Tubulin (a type of α-Tubulin), plays a new role in controlling the fate of male germline stem cells (GSC). In this study, we have found that Drosophila α4-Tubulin is required intrinsically and extrinsically for GSCs maintenance. Results from green fluorescent protein (GFP)-transgene reporter assays show that the gene αTub67C is not required for Dpp/Gbb signaling silencing of bam expression, suggesting that αTub67C functions downstream of or parallel to bam, and is independent of Gbb/Dpp-bam signaling pathway. Furthermore, overexpression of αTub67C fails to obviously increase the number of GSC/Gonialblast (GB). Given that the α-tubulin genes are evolutionarily conserved from yeast to human, which triggers us to study the more roles of the gene α-tubulin in other animals in the future.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Células Germinativas/citologia , Células Germinativas/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Testículo/citologia , Tubulina (Proteína)/metabolismo , Animais , Drosophila melanogaster/genética , Inativação Gênica , Masculino , Mutação/genética , Fenótipo , Transdução de Sinais , Tubulina (Proteína)/genética
15.
Elife ; 102021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34018925

RESUMO

Thirst is a motivational state that drives behaviors to obtain water for fluid homeostasis. We identified two types of central brain interneurons that regulate thirsty water seeking in Drosophila, that we term the Janu neurons. Janu-GABA, a local interneuron in the subesophageal zone, is activated by water deprivation and is specific to thirsty seeking. Janu-AstA projects from the subesophageal zone to the superior medial protocerebrum, a higher order processing area. Janu-AstA signals with the neuropeptide Allatostatin A to promote water seeking and to inhibit feeding behavior. NPF (Drosophila NPY) neurons are postsynaptic to Janu-AstA for water seeking and feeding through the AstA-R2 galanin-like receptor. NPF neurons use NPF to regulate thirst and hunger behaviors. Flies choose Janu neuron activation, suggesting that thirsty seeking up a humidity gradient is rewarding. These findings identify novel central brain circuit elements that coordinate internal state drives to selectively control motivated seeking behavior.


Assuntos
Encéfalo/fisiologia , Ingestão de Líquidos , Drosophila melanogaster/fisiologia , Comportamento Alimentar , Neurônios GABAérgicos/fisiologia , Fome , Interneurônios/fisiologia , Sede , Animais , Animais Geneticamente Modificados , Encéfalo/citologia , Encéfalo/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Neurônios GABAérgicos/metabolismo , Interneurônios/metabolismo , Inibição Neural , Neuropeptídeo Y/metabolismo , Oligopeptídeos/metabolismo , Receptores de Neuropeptídeos/metabolismo
16.
J Cell Biol ; 220(8)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34042945

RESUMO

γ-Tubulin ring complexes (γ-TuRCs) nucleate microtubules. They are recruited to centrosomes in dividing cells via binding to N-terminal CM1 domains within γ-TuRC-tethering proteins, including Drosophila Centrosomin (Cnn). Binding promotes microtubule nucleation and is restricted to centrosomes in dividing cells, but the mechanism regulating binding remains unknown. Here, we identify an extreme N-terminal CM1 autoinhibition (CAI) domain found specifically within the centrosomal isoform of Cnn (Cnn-C) that inhibits γ-TuRC binding. Robust binding occurs after removal of the CAI domain or with the addition of phosphomimetic mutations, suggesting that phosphorylation helps relieve inhibition. We show that regulation of Cnn binding to γ-TuRCs is isoform specific and that misregulation of binding can result in ectopic cytosolic microtubules and major defects during cell division. We also find that human CDK5RAP2 is autoinhibited from binding γ-TuRCs, suggesting conservation across species. Overall, our results shed light on how and why CM1 domain binding to γ-TuRCs is regulated.


Assuntos
Divisão Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Fertilidade , Células HEK293 , Proteínas de Homeodomínio/genética , Humanos , Masculino , Microscopia Confocal , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Relação Estrutura-Atividade
17.
Dev Biol ; 477: 22-34, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34004181

RESUMO

Branching networks are a very common feature of multicellular animals and underlie the formation and function of numerous organs including the nervous system, the respiratory system, the vasculature and many internal glands. These networks range from subcellular structures such as dendritic trees to large multicellular tissues such as the lungs. The production of branched structures by single cells, so called subcellular branching, which has been better described in neurons and in cells of the respiratory and vascular systems, involves complex cytoskeletal remodelling events. In Drosophila, tracheal system terminal cells (TCs) and nervous system dendritic arborisation (da) neurons are good model systems for these subcellular branching processes. During development, the generation of subcellular branches by single-cells is characterized by extensive remodelling of the microtubule (MT) network and actin cytoskeleton, followed by vesicular transport and membrane dynamics. In this review, we describe the current knowledge on cytoskeletal regulation of subcellular branching, based on the terminal cells of the Drosophila tracheal system, but drawing parallels with dendritic branching and vertebrate vascular subcellular branching.


Assuntos
Diferenciação Celular/fisiologia , Citoesqueleto/fisiologia , Drosophila melanogaster/embriologia , Morfogênese , Neurogênese/fisiologia , Actinas/fisiologia , Animais , Comunicação Celular , Drosophila melanogaster/citologia , Endotélio/embriologia , Humanos , Microtúbulos/fisiologia , Análise de Célula Única , Traqueia/citologia , Traqueia/embriologia
18.
Elife ; 102021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33856346

RESUMO

The nuclear pore complex (NPC) is the principal gateway between nucleus and cytoplasm that enables exchange of macromolecular cargo. Composed of multiple copies of ~30 different nucleoporins (Nups), the NPC acts as a selective portal, interacting with factors which individually license passage of specific cargo classes. Here we show that two Nups of the inner channel, Nup54 and Nup58, are essential for transposon silencing via the PIWI-interacting RNA (piRNA) pathway in the Drosophila ovary. In ovarian follicle cells, loss of Nup54 and Nup58 results in compromised piRNA biogenesis exclusively from the flamenco locus, whereas knockdowns of other NPC subunits have widespread consequences. This provides evidence that some Nups can acquire specialised roles in tissue-specific contexts. Our findings consolidate the idea that the NPC has functions beyond simply constituting a barrier to nuclear/cytoplasmic exchange as genomic loci subjected to strong selective pressure can exploit NPC subunits to facilitate their expression.


Assuntos
Elementos de DNA Transponíveis , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Ovário/metabolismo , Interferência de RNA , Animais , Animais Geneticamente Modificados , Linhagem Celular , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Regulação da Expressão Gênica , Poro Nuclear/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Ovário/citologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
19.
Dev Cell ; 56(10): 1469-1483.e5, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33891900

RESUMO

During embryo development, tissues often undergo multiple concomitant changes in shape. It is unclear which signaling pathways and cellular mechanisms are responsible for multiple simultaneous tissue shape transformations. We focus on the process of concomitant tissue folding and extension that is key during gastrulation and neurulation. We use the Drosophila embryo as model system and focus on the process of mesoderm invagination. Here, we show that the prospective mesoderm simultaneously folds and extends. We report that mesoderm cells, under the control of anterior-posterior and dorsal-ventral gene patterning synergy, establish two sets of adherens junctions at different apical-basal positions with specialized functions: while apical junctions drive apical constriction initiating tissue bending, lateral junctions concomitantly drive polarized cell intercalation, resulting in tissue convergence-extension. Thus, epithelial cells devise multiple specialized junctional sets that drive composite morphogenetic processes under the synergistic control of apparently orthogonal signaling sources.


Assuntos
Junções Aderentes/metabolismo , Drosophila melanogaster/embriologia , Mesoderma/embriologia , Morfogênese , Animais , Fenômenos Biomecânicos , Padronização Corporal , Proteínas de Ciclo Celular/metabolismo , Polaridade Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Embrião não Mamífero/metabolismo , Mesoderma/citologia , Miosina Tipo II/metabolismo , Fatores de Transcrição da Família Snail/metabolismo
20.
Nature ; 593(7858): 244-248, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33911283

RESUMO

Coordinated activity across networks of neurons is a hallmark of both resting and active behavioural states in many species1-5. These global patterns alter energy metabolism over seconds to hours, which underpins the widespread use of oxygen consumption and glucose uptake as proxies of neural activity6,7. However, whether changes in neural activity are causally related to metabolic flux in intact circuits on the timescales associated with behaviour is unclear. Here we combine two-photon microscopy of the fly brain with sensors that enable the simultaneous measurement of neural activity and metabolic flux, across both resting and active behavioural states. We demonstrate that neural activity drives changes in metabolic flux, creating a tight coupling between these signals that can be measured across brain networks. Using local optogenetic perturbation, we demonstrate that even transient increases in neural activity result in rapid and persistent increases in cytosolic ATP, which suggests that neuronal metabolism predictively allocates resources to anticipate the energy demands of future activity. Finally, our studies reveal that the initiation of even minimal behavioural movements causes large-scale changes in the pattern of neural activity and energy metabolism, which reveals a widespread engagement of the brain. As the relationship between neural activity and energy metabolism is probably evolutionarily ancient and highly conserved, our studies provide a critical foundation for using metabolic proxies to capture changes in neural activity.


Assuntos
Comportamento Animal , Encéfalo/citologia , Encéfalo/fisiologia , Drosophila melanogaster/metabolismo , Drosophila melanogaster/fisiologia , Redes e Vias Metabólicas , Neurônios/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Encéfalo/metabolismo , Drosophila melanogaster/citologia , Metabolismo Energético , Feminino , Masculino , Vias Neurais , Optogenética , Descanso
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