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1.
Elife ; 122023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724009

RESUMO

Drosophila melanogaster reproductive behaviors are orchestrated by fruitless neurons. We performed single-cell RNA-sequencing on pupal neurons that produce sex-specifically spliced fru transcripts, the fru P1-expressing neurons. Uniform Manifold Approximation and Projection (UMAP) with clustering generates an atlas containing 113 clusters. While the male and female neurons overlap in UMAP space, more than half the clusters have sex differences in neuron number, and nearly all clusters display sex-differential expression. Based on an examination of enriched marker genes, we annotate clusters as circadian clock neurons, mushroom body Kenyon cell neurons, neurotransmitter- and/or neuropeptide-producing, and those that express doublesex. Marker gene analyses also show that genes that encode members of the immunoglobulin superfamily of cell adhesion molecules, transcription factors, neuropeptides, neuropeptide receptors, and Wnts have unique patterns of enriched expression across the clusters. In vivo spatial gene expression links to the clusters are examined. A functional analysis of fru P1 circadian neurons shows they have dimorphic roles in activity and period length. Given that most clusters are comprised of male and female neurons indicates that the sexes have fru P1 neurons with common gene expression programs. Sex-specific expression is overlaid on this program, to build the potential for vastly different sex-specific behaviors.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Feminino , Masculino , Drosophila melanogaster/fisiologia , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Transcriptoma , Comportamento Sexual Animal/fisiologia , Neurônios/fisiologia , Caracteres Sexuais , Proteínas do Tecido Nervoso/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Curr Biol ; 33(2): 321-335.e6, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36603587

RESUMO

Visual systems extract multiple features from a scene using parallel neural circuits. Ultimately, the separate neural signals must come together to coherently influence action. Here, we characterize a circuit in Drosophila that integrates multiple visual features related to imminent threats to drive evasive locomotor turns. We identified, using genetic perturbation methods, a pair of visual projection neurons (LPLC2) and descending neurons (DNp06) that underlie evasive flight turns in response to laterally moving or approaching visual objects. Using two-photon calcium imaging or whole-cell patch clamping, we show that these cells indeed respond to both translating and approaching visual patterns. Furthermore, by measuring visual responses of LPLC2 neurons after genetically silencing presynaptic motion-sensing neurons, we show that their visual properties emerge by integrating multiple visual features across two early visual structures: the lobula and the lobula plate. This study highlights a clear example of how distinct visual signals converge on a single class of visual neurons and then activate premotor neurons to drive action, revealing a concise visuomotor pathway for evasive flight maneuvers in Drosophila.


Assuntos
Drosophila , Percepção de Movimento , Animais , Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Neurônios Motores/fisiologia , Interneurônios/metabolismo , Cálcio/metabolismo , Vias Visuais , Percepção de Movimento/fisiologia , Voo Animal/fisiologia
3.
Sci Rep ; 13(1): 383, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611081

RESUMO

Acoustic communication signals diversify even on short evolutionary time scales. To understand how the auditory system underlying acoustic communication could evolve, we conducted a systematic comparison of the early stages of the auditory neural circuit involved in song information processing between closely-related fruit-fly species. Male Drosophila melanogaster and D. simulans produce different sound signals during mating rituals, known as courtship songs. Female flies from these species selectively increase their receptivity when they hear songs with conspecific temporal patterns. Here, we firstly confirmed interspecific differences in temporal pattern preferences; D. simulans preferred pulse songs with longer intervals than D. melanogaster. Primary and secondary song-relay neurons, JO neurons and AMMC-B1 neurons, shared similar morphology and neurotransmitters between species. The temporal pattern preferences of AMMC-B1 neurons were also relatively similar between species, with slight but significant differences in their band-pass properties. Although the shift direction of the response property matched that of the behavior, these differences are not large enough to explain behavioral differences in song preferences. This study enhances our understanding of the conservation and diversification of the architecture of the early-stage neural circuit which processes acoustic communication signals.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Masculino , Feminino , Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Corte , Evolução Biológica , Neurônios , Drosophila simulans , Comportamento Sexual Animal/fisiologia , Vocalização Animal/fisiologia
4.
Elife ; 122023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36692370

RESUMO

A fundamental question in sensory processing is how different channels of sensory input are processed to regulate behavior. Different input channels may converge onto common downstream pathways to drive the same behaviors, or they may activate separate pathways to regulate distinct behaviors. We investigated this question in the Drosophila bitter taste system, which contains diverse bitter-sensing cells residing in different taste organs. First, we optogenetically activated subsets of bitter neurons within each organ. These subsets elicited broad and highly overlapping behavioral effects, suggesting that they converge onto common downstream pathways, but we also observed behavioral differences that argue for biased convergence. Consistent with these results, transsynaptic tracing revealed that bitter neurons in different organs connect to overlapping downstream pathways with biased connectivity. We investigated taste processing in one type of downstream bitter neuron that projects to the higher brain. These neurons integrate input from multiple organs and regulate specific taste-related behaviors. We then traced downstream circuits, providing the first glimpse into taste processing in the higher brain. Together, these results reveal that different bitter inputs are selectively integrated early in the circuit, enabling the pooling of information, while the circuit then diverges into multiple pathways that may have different roles.


Assuntos
Drosophila melanogaster , Paladar , Animais , Paladar/fisiologia , Drosophila melanogaster/fisiologia , Percepção Gustatória/fisiologia , Drosophila , Encéfalo/fisiologia
5.
Curr Biol ; 33(2): 351-363.e3, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36610393

RESUMO

Circadian clocks align various behaviors such as locomotor activity, sleep/wake, feeding, and mating to times of day that are most adaptive. How rhythmic information in pacemaker circuits is translated to neuronal outputs is not well understood. Here, we used brain-wide, 24-h in vivo calcium imaging in the Drosophila brain and searched for circadian rhythmic activity among identified clusters of dopaminergic (DA) and peptidergic neurosecretory (NS) neurons. Such rhythms were widespread and imposed by the PERIOD-dependent clock activity within the ∼150-cell circadian pacemaker network. The rhythms displayed either a morning (M), evening (E), or mid-day (MD) phase. Different subgroups of circadian pacemakers imposed neural activity rhythms onto different downstream non-clock neurons. Outputs from the canonical M and E pacemakers converged to regulate DA-PPM3 and DA-PAL neurons. E pacemakers regulate the evening-active DA-PPL1 neurons. In addition to these canonical M and E oscillators, we present evidence for a third dedicated phase occurring at mid-day: the l-LNv pacemakers present the MD activity peak, and they regulate the MD-active DA-PPM1/2 neurons and three distinct NS cell types. Thus, the Drosophila circadian pacemaker network is a polyphasic rhythm generator. It presents dedicated M, E, and MD phases that are functionally transduced as neuronal outputs to organize diverse daily activity patterns in downstream circuits.


Assuntos
Relógios Circadianos , Proteínas de Drosophila , Animais , Drosophila melanogaster/fisiologia , Atividade Motora/fisiologia , Ritmo Circadiano/fisiologia , Drosophila/fisiologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Neurônios Dopaminérgicos/metabolismo
6.
Curr Biol ; 33(2): 336-350.e5, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36584676

RESUMO

Circadian clocks are self-sustained molecular oscillators controlling daily changes of behavioral activity and physiology. For functional reliability and precision, the frequency of these molecular oscillations must be stable at different environmental temperatures, known as "temperature compensation." Despite being an intrinsic property of all circadian clocks, this phenomenon is not well understood at the molecular level. Here, we use behavioral and molecular approaches to characterize a novel mutation in the period (per) clock gene of Drosophila melanogaster, which alters a predicted nuclear export signal (NES) of the PER protein and affects temperature compensation. We show that this new perI530A allele leads to progressively longer behavioral periods and clock oscillations with increasing temperature in both clock neurons and peripheral clock cells. While the mutant PERI530A protein shows normal circadian fluctuations and post-translational modifications at cool temperatures, increasing temperatures lead to both severe amplitude dampening and hypophosphorylation of PERI530A. We further show that PERI530A displays reduced repressor activity at warmer temperatures, presumably because it cannot inactivate the transcription factor CLOCK (CLK), indicated by temperature-dependent altered CLK post-translational modification in perI530A flies. With increasing temperatures, nuclear accumulation of PERI530A within clock neurons is increased, suggesting that wild-type PER is exported out of the nucleus at warm temperatures. Downregulating the nuclear export factor CRM1 also leads to temperature-dependent changes of behavioral rhythms, suggesting that the PER NES and the nuclear export of clock proteins play an important role in temperature compensation of the Drosophila circadian clock.


Assuntos
Relógios Circadianos , Proteínas de Drosophila , Animais , Drosophila/metabolismo , Relógios Circadianos/genética , Drosophila melanogaster/fisiologia , Temperatura , Proteínas de Drosophila/metabolismo , Ritmo Circadiano/fisiologia , Transporte Ativo do Núcleo Celular , Reprodutibilidade dos Testes , Mutação , Proteínas CLOCK/genética
7.
Curr Biol ; 33(2): 215-227.e3, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36528025

RESUMO

In mammals, learning circuits play an essential role in energy balance by creating associations between sensory cues and the rewarding qualities of food. This process is altered by diet-induced obesity, but the causes and mechanisms are poorly understood. Here, we exploited the relative simplicity and wealth of knowledge about the D. melanogaster reinforcement learning network, the mushroom body, in order to study the relationship between the dietary environment, dopamine-induced plasticity, and food associations. We show flies that are fed a high-sugar diet cannot make associations between sensory cues and the rewarding properties of sugar. This deficit was caused by diet exposure, not fat accumulation, and specifically by lower dopamine-induced plasticity onto mushroom body output neurons (MBONs) during learning. Importantly, food memories dynamically tune the output of MBONs during eating, which instead remains fixed in sugar-diet animals. Interestingly, manipulating the activity of MBONs influenced eating and fat mass, depending on the diet. Altogether, this work advances our fundamental understanding of the mechanisms, causes, and consequences of the dietary environment on reinforcement learning and ingestive behavior.


Assuntos
Dopamina , Drosophila melanogaster , Animais , Drosophila melanogaster/fisiologia , Comportamento Alimentar/fisiologia , Aprendizagem/fisiologia , Açúcares , Corpos Pedunculados/fisiologia , Ingestão de Alimentos , Mamíferos
8.
J Insect Physiol ; 144: 104472, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549582

RESUMO

Limiting calories or specific nutrients without malnutrition, otherwise known as dietary restriction (DR), has been shown to extend lifespan and reduce reproduction across a broad range of taxa. Our recent findings in Drosophila melanogaster show that supplementing flies on macronutrient-rich diets with additional cholesterol can extend lifespan to the same extent as DR, while also sustaining high egg production. Thus, DR may be beneficial for lifespan because it reduces egg production which in turn reduces the mother's demand for sterols, thus supporting longer lifespan. It is also possible that mothers live longer and lay more eggs on high sterol diets because the diet triggers enhanced somatic maintenance and promotes egg production, but at the cost of diminished egg quality. To test this, we measured the viability of eggs and development of offspring from mothers fed either cholesterol-sufficient or cholesterol-limiting diets. We found that even when the mother's diet was completely devoid of cholesterol, viable egg production persisted for ∼10 days. Furthermore, we show that sterol-supplemented flies with long lives lay eggs that have high viability and the same developmental potential as those laid by shorter lived mothers on sterol limiting diets. These findings suggest that offspring viability is not a hidden cost of lifespan extension seen in response to dietary sterol supplementation.


Assuntos
Drosophila melanogaster , Óvulo , Feminino , Animais , Drosophila melanogaster/fisiologia , Longevidade , Esteróis , Dieta , Colesterol
9.
J Neurosci ; 43(5): 764-786, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535771

RESUMO

The ellipsoid body (EB) is a major structure of the central complex of the Drosophila melanogaster brain. Twenty-two subtypes of EB ring neurons have been identified based on anatomic and morphologic characteristics by light-level microscopy and EM connectomics. A few studies have associated ring neurons with the regulation of sleep homeostasis and structure. However, cell type-specific and population interactions in the regulation of sleep remain unclear. Using an unbiased thermogenetic screen of EB drivers using female flies, we found the following: (1) multiple ring neurons are involved in the modulation of amount of sleep and structure in a synergistic manner; (2) analysis of data for ΔP(doze)/ΔP(wake) using a mixed Gaussian model detected 5 clusters of GAL4 drivers which had similar effects on sleep pressure and/or depth: lines driving arousal contained R4m neurons, whereas lines that increased sleep pressure had R3m cells; (3) a GLM analysis correlating ring cell subtype and activity-dependent changes in sleep parameters across all lines identified several cell types significantly associated with specific sleep effects: R3p was daytime sleep-promoting, and R4m was nighttime wake-promoting; and (4) R3d cells present in 5HT7-GAL4 and in GAL4 lines, which exclusively affect sleep structure, were found to contribute to fragmentation of sleep during both day and night. Thus, multiple subtypes of ring neurons distinctively control sleep amount and/or structure. The unique highly interconnected structure of the EB suggests a local-network model worth future investigation; understanding EB subtype interactions may provide insight how sleep circuits in general are structured.SIGNIFICANCE STATEMENT How multiple brain regions, with many cell types, can coherently regulate sleep remains unclear, but identification of cell type-specific roles can generate opportunities for understanding the principles of integration and cooperation. The ellipsoid body (EB) of the fly brain exhibits a high level of connectivity and functional heterogeneity yet is able to tune multiple behaviors in real-time, including sleep. Leveraging the powerful genetic tools available in Drosophila and recent progress in the characterization of the morphology and connectivity of EB ring neurons, we identify several EB subtypes specifically associated with distinct aspects of sleep. Our findings will aid in revealing the rules of coding and integration in the brain.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Feminino , Drosophila/metabolismo , Drosophila melanogaster/fisiologia , Sono/fisiologia , Neurônios/fisiologia , Nível de Alerta/fisiologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
10.
Nat Commun ; 13(1): 7810, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36535958

RESUMO

Dietary composition affects food preference in animals. High sugar intake suppresses sweet sensation from insects to humans, but the molecular basis of this suppression is largely unknown. Here, we reveal that sugar intake in Drosophila induces the gut to express and secrete Hedgehog (Hh) into the circulation. We show that the midgut secreted Hh localize to taste sensilla and suppresses sweet sensation, perception, and preference. We further find that the midgut Hh inhibits Hh signalling in the sweet taste neurons. Our electrophysiology studies demonstrate that the midgut Hh signal also suppresses bitter taste and some odour responses, affecting overall food perception and preference. We further show that the level of sugar intake during a critical window early in life, sets the adult gut Hh expression and sugar perception. Our results together reveal a bottom-up feedback mechanism involving a "gut-taste neuron axis" that regulates food sensation and preference.


Assuntos
Drosophila melanogaster , Proteínas Hedgehog , Neurônios , Paladar , Animais , Drosophila melanogaster/fisiologia , Preferências Alimentares , Proteínas Hedgehog/metabolismo , Neurônios/fisiologia , Açúcares/metabolismo , Paladar/fisiologia , Proteínas de Drosophila/metabolismo
11.
BMC Biol ; 20(1): 279, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36514080

RESUMO

BACKGROUND: Male-derived seminal fluid proteins (SFPs) that enter female fruitflies during mating induce a myriad of physiological and behavioral changes, optimizing fertility of the mating pair. Some post-mating changes in female Drosophila melanogaster persist for ~10-14 days. Their long-term persistence is because the seminal protein that induces these particular changes, the Sex Peptide (SP), is retained long term in females by binding to sperm, with gradual release of its active domain from sperm. Several other "long-term response SFPs" (LTR-SFPs) "prime" the binding of SP to sperm. Whether female factors play a role in this process is unknown, though it is important to study both sexes for a comprehensive physiological understanding of SFP/sperm interactions and for consideration in models of sexual conflict. RESULTS: We report here that sperm in male ejaculates bind SP more weakly than sperm that have entered females. Moreover, we show that the amount of SP, and other SFPs, bound to sperm increases with time and transit of individual seminal proteins within the female reproductive tract (FRT). Thus, female contributions are needed for maximal and appropriate binding of SP, and other SFPs, to sperm. Towards understanding the source of female molecular contributions, we ablated spermathecal secretory cells (SSCs) and/or parovaria (female accessory glands), which contribute secretory proteins to the FRT. We found no dramatic change in the initial levels of SP bound to sperm stored in mated females with ablated or defective SSCs and/or parovaria, indicating that female molecules that facilitate the binding of SP to sperm are not uniquely derived from SSCs and parovaria. However, we observed higher levels of SP (and sperm) retention long term in females whose SSCs and parovaria had been ablated, indicating secretions from these female tissues are necessary for the gradual release of Sex Peptide's active region from stored sperm. CONCLUSION: This study reveals that the SP-sperm binding pathway is not entirely male-derived and that female contributions are needed to regulate the levels of SP associated with sperm stored in their storage sites.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Masculino , Feminino , Drosophila melanogaster/fisiologia , Proteínas de Drosophila/metabolismo , Sêmen/metabolismo , Espermatozoides/fisiologia , Comportamento Sexual Animal/fisiologia , Peptídeos/metabolismo
12.
Proc Biol Sci ; 289(1989): 20222054, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36515118

RESUMO

Among the many wonders of nature, the sense of smell of the fly Drosophila melanogaster might seem, at first glance, of esoteric interest. Nevertheless, for over a century, the 'nose' of this insect has been an extraordinary system to explore questions in animal behaviour, ecology and evolution, neuroscience, physiology and molecular genetics. The insights gained are relevant for our understanding of the sensory biology of vertebrates, including humans, and other insect species, encompassing those detrimental to human health. Here, I present an overview of our current knowledge of D. melanogaster olfaction, from molecules to behaviours, with an emphasis on the historical motivations of studies and illustration of how technical innovations have enabled advances. I also highlight some of the pressing and long-term questions.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Humanos , Drosophila melanogaster/fisiologia , Olfato/fisiologia , Comportamento Animal , Ecologia , Insetos
13.
BMC Biol ; 20(1): 283, 2022 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-36527001

RESUMO

BACKGROUND: Like most living organisms, the fruit fly Drosophila melanogaster exhibits strong and diverse behavioural reactions to light. Drosophila is a diurnal animal that displays both short- and long-term responses to light, important for, instance, in avoidance and light wavelength preference, regulation of eclosion, courtship, and activity, and provides an important model organism for understanding the regulation of circadian rhythms both at molecular and circuit levels. However, the assessment and comparison of light-based behaviours is still a challenge, mainly due to the lack of a standardised platform to measure behaviour and different protocols created across studies. Here, we describe the Drosophila Interactive System for Controlled Optical manipulations (DISCO), a low-cost, automated, high-throughput device that records the flies' activity using infrared beams while performing LED light manipulations. RESULTS: To demonstrate the effectiveness of this tool and validate its potential as a standard platform, we developed a number of distinct assays, including measuring the locomotor response of flies exposed to sudden darkness (lights-off) stimuli. Both white-eyed and red-eyed wild-type flies exhibit increased activity after the application of stimuli, while no changes can be observed in Fmr1 null allele flies, a model of fragile X syndrome. Next, to demonstrate the use of DISCO in long-term protocols, we monitored the circadian rhythm of the flies for 48 h while performing an alcohol preference test. We show that increased alcohol consumption happens intermittently throughout the day, especially in the dark phases. Finally, we developed a feedback-loop algorithm to implement a place preference test based on the flies' innate aversion to blue light and preference for green light. We show that both white-eyed and red-eyed wild-type flies were able to learn to avoid the blue-illuminated zones. CONCLUSIONS: Our results demonstrate the versatility of DISCO for a range of protocols, indicating that this platform can be used in a variety of ways to study light-dependent behaviours in flies.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Drosophila melanogaster/fisiologia , Ritmo Circadiano/fisiologia , Drosophila/fisiologia , Atividade Motora/fisiologia , Visão Ocular , Proteína do X Frágil de Retardo Mental
14.
J Exp Biol ; 225(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36477887

RESUMO

Most insects can acclimate to changes in their thermal environment and counteract temperature effects on neuromuscular function. At the critical thermal minimum, a spreading depolarization (SD) event silences central neurons, but the temperature at which this event occurs can be altered through acclimation. SD is triggered by an inability to maintain ion homeostasis in the extracellular space in the brain and is characterized by a rapid surge in extracellular K+ concentration, implicating ion pump and channel function. Here, we focused on the role of the Na+/K+-ATPase specifically in lowering the SD temperature in cold-acclimated Drosophila melanogaster. After first confirming cold acclimation altered SD onset, we investigated the dependency of the SD event on Na+/K+-ATPase activity by injecting the inhibitor ouabain into the head of the flies to induce SD over a range of temperatures. Latency to SD followed the pattern of a thermal performance curve, but cold acclimation resulted in a left-shift of the curve to an extent similar to its effect on the SD temperature. With Na+/K+-ATPase activity assays and immunoblots, we found that cold-acclimated flies have ion pumps that are less sensitive to temperature, but do not differ in their overall abundance in the brain. Combined, these findings suggest a key role for plasticity in Na+/K+-ATPase thermal sensitivity in maintaining central nervous system function in the cold, and more broadly highlight that a single ion pump can be an important determinant of whether insects can respond to their environment to remain active at low temperatures.


Assuntos
Temperatura Baixa , Drosophila melanogaster , Animais , Temperatura , Drosophila melanogaster/fisiologia , Aclimatação/fisiologia , Adenosina Trifosfatases , ATPase Trocadora de Sódio-Potássio/metabolismo
15.
Nutrients ; 14(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36558363

RESUMO

In traditional Chinese medicine, soft-shelled turtle protein and peptides serve as a nutraceutical for prolonging the lifespan. However, their effects on anti-aging have not been clarified scientifically in vivo. This study aimed to determine whether soft-shelled turtle peptides (STP) could promote the lifespan and healthspan in Drosophila melanogaster and the underlying molecular mechanisms. Herein, STP supplementation prolonged the mean lifespan by 20.23% and 9.04% in males and females, respectively, delaying the aging accompanied by climbing ability decline, enhanced gut barrier integrity, and improved anti-oxidation, starvation, and heat stress abilities, while it did not change the daily food intake. Mechanistically, STP enhanced autophagy and decreased oxidative stress by downregulating the target of rapamycin (TOR) signaling pathway. In addition, 95.18% of peptides from the identified sequences in STP could exert potential inhibitory effects on TOR through hydrogen bonds, van der Walls, hydrophobic interactions, and electrostatic interactions. The current study could provide a theoretical basis for the full exploitation of soft-shelled turtle aging prevention.


Assuntos
Longevidade , Tartarugas , Animais , Masculino , Feminino , Drosophila , Drosophila melanogaster/fisiologia , Peptídeos/farmacologia , Peptídeos/química
16.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499123

RESUMO

Allopathic medicines play a key role in the prevention and treatment of diseases. However, long-term consumption of these medicines may cause serious undesirable effects that harm human health. Plant-based medicines have emerged as alternatives to allopathic medicines because of their rare side effects. They contain several compounds that have the potential to improve health and treat diseases in humans, including their function as immunomodulators to treat immune-related diseases. Thus, the discovery of potent and safe immunomodulators from plants is gaining considerable research interest. Recently, Drosophila has gained prominence as a model organism in evaluating the efficacy of plant and plant-derived substances. Drosophila melanogaster "fruit fly" is a well-known, high-throughput model organism that has been used to study different biological aspects of development and diseases for more than 110 years. Most developmental and cell signaling pathways and 75% of human disease-related genes are conserved between humans and Drosophila. Using Drosophila, one can easily examine the pharmacological effects of plants/plant-derived components by employing a variety of tests in flies, such as survival, anti-inflammatory, antioxidant, and cell death tests. This review focused on D. melanogaster's potential for identifying immunomodulatory features associated with plants/plant-derived components.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Humanos , Drosophila melanogaster/fisiologia , Modelos Animais , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Adjuvantes Imunológicos/farmacologia
17.
Nature ; 611(7937): 754-761, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36352224

RESUMO

Odour plumes in the wild are spatially complex and rapidly fluctuating structures carried by turbulent airflows1-4. To successfully navigate plumes in search of food and mates, insects must extract and integrate multiple features of the odour signal, including odour identity5, intensity6 and timing6-12. Effective navigation requires balancing these multiple streams of olfactory information and integrating them with other sensory inputs, including mechanosensory and visual cues9,12,13. Studies dating back a century have indicated that, of these many sensory inputs, the wind provides the main directional cue in turbulent plumes, leading to the longstanding model of insect odour navigation as odour-elicited upwind motion6,8-12,14,15. Here we show that Drosophila melanogaster shape their navigational decisions using an additional directional cue-the direction of motion of odours-which they detect using temporal correlations in the odour signal between their two antennae. Using a high-resolution virtual-reality paradigm to deliver spatiotemporally complex fictive odours to freely walking flies, we demonstrate that such odour-direction sensing involves algorithms analogous to those in visual-direction sensing16. Combining simulations, theory and experiments, we show that odour motion contains valuable directional information that is absent from the airflow alone, and that both Drosophila and virtual agents are aided by that information in navigating naturalistic plumes. The generality of our findings suggests that odour-direction sensing may exist throughout the animal kingdom and could improve olfactory robot navigation in uncertain environments.


Assuntos
Drosophila melanogaster , Percepção de Movimento , Odorantes , Percepção Olfatória , Navegação Espacial , Vento , Animais , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/fisiologia , Odorantes/análise , Navegação Espacial/fisiologia , Percepção de Movimento/fisiologia , Fatores de Tempo , Percepção Olfatória/fisiologia , Antenas de Artrópodes/fisiologia , Sinais (Psicologia) , Caminhada/fisiologia
18.
Elife ; 112022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383075

RESUMO

Deciphering the genetic architecture of human cardiac disorders is of fundamental importance but their underlying complexity is a major hurdle. We investigated the natural variation of cardiac performance in the sequenced inbred lines of the Drosophila Genetic Reference Panel (DGRP). Genome-wide associations studies (GWAS) identified genetic networks associated with natural variation of cardiac traits which were used to gain insights as to the molecular and cellular processes affected. Non-coding variants that we identified were used to map potential regulatory non-coding regions, which in turn were employed to predict transcription factors (TFs) binding sites. Cognate TFs, many of which themselves bear polymorphisms associated with variations of cardiac performance, were also validated by heart-specific knockdown. Additionally, we showed that the natural variations associated with variability in cardiac performance affect a set of genes overlapping those associated with average traits but through different variants in the same genes. Furthermore, we showed that phenotypic variability was also associated with natural variation of gene regulatory networks. More importantly, we documented correlations between genes associated with cardiac phenotypes in both flies and humans, which supports a conserved genetic architecture regulating adult cardiac function from arthropods to mammals. Specifically, roles for PAX9 and EGR2 in the regulation of the cardiac rhythm were established in both models, illustrating that the characteristics of natural variations in cardiac function identified in Drosophila can accelerate discovery in humans.


Assuntos
Drosophila melanogaster , Coração , Locos de Características Quantitativas , Animais , Humanos , Drosophila melanogaster/fisiologia , Redes Reguladoras de Genes , Variação Genética , Estudo de Associação Genômica Ampla , Fenótipo , Coração/fisiologia
19.
Elife ; 112022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36398882

RESUMO

The agricultural pest Drosophila suzukii differs from most other Drosophila species in that it lays eggs in ripe, rather than overripe, fruit. Previously, we showed that changes in bitter taste sensation accompanied this adaptation (Dweck et al., 2021). Here, we show that D. suzukii has also undergone a variety of changes in sweet taste sensation. D. suzukii has a weaker preference than Drosophila melanogaster for laying eggs on substrates containing all three primary fruit sugars: sucrose, fructose, and glucose. Major subsets of D. suzukii taste sensilla have lost electrophysiological responses to sugars. Expression of several key sugar receptor genes is reduced in the taste organs of D. suzukii. By contrast, certain mechanosensory channel genes, including no mechanoreceptor potential C, are expressed at higher levels in the taste organs of D. suzukii, which has a higher preference for stiff substrates. Finally, we find that D. suzukii responds differently from D. melanogaster to combinations of sweet and mechanosensory cues. Thus, the two species differ in sweet sensation, mechanosensation, and their integration, which are all likely to contribute to the differences in their egg-laying preferences in nature.


Assuntos
Drosophila melanogaster , Drosophila , Animais , Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Açúcares , Oviposição , Sensação
20.
J Insect Physiol ; 143: 104456, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36396076

RESUMO

Plastic responses to heat stress have been shown to temporarily increase heat stress tolerance in many small ectotherms. Heat shock proteins (Hsps) have previously been shown to play a role in this induced heat stress tolerance. The heat shock response is fast but short lived, with the cellular Hsp concentration peaking within a few hours after induction. Induced heat stress tolerance, on the other hand, peaks 16-32 h after induction. Therefore, the inducible heat stress response must depend on additional mechanisms. The Turandot gene family has been suggested as a candidate. It contains eight genes that are all upregulated to some degree following heat stress in Drosophila melanogaster. Previously, Turandot A (totA) and Turandot X (totX) have been linked to induced heat stress tolerance. The study presented here aimed to investigate the temporal dynamics of Turandot expression and the functional role of totA and totC for heat stress tolerance. This was done by assaying the temporal heat tolerance and Turandot gene expression after a heat insult, and by exposing Turandot gene knock down flies to a range of heat hardening treatments, and evaluating the effects on heat tolerance. Successful gene knock down was verified by gene expression assays. In addition, expression of hsp70A was included. Both totA, totC, and hsp70A expression increased following a heat hardening treatment, while the results for totX were less clear. The expression of totC temporally co-occurred with and was functionally linked to increased heat tolerance. Expression of totA did not have a significant effect on heat stress tolerance. The complexity of inducible heat tolerance was underlined by the result that knock down of Turandot genes led to increased expression of hsp70. The results suggest that heat tolerance is determined by the interaction between several mechanisms, of which Turandot genes constitute one such mechanism.


Assuntos
Proteínas de Drosophila , Termotolerância , Animais , Drosophila melanogaster/fisiologia , Termotolerância/genética , Proteínas de Drosophila/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Temperatura Alta
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