The molecular mechanisms of diapause and diapause-like reversible arrest

Biochemical Society Transactions, Год журнала: 2023, Номер 51(5), С. 1847 - 1856

Опубликована: Окт. 6, 2023

Diapause is a protective mechanism that many organisms deploy to overcome environmental adversities. extends lifespan and fertility enhance the reproductive success survival of species. Although diapause states have been known employed for commercial purposes, example in silk industry, detailed molecular cell biological studies are an exciting frontier. Understanding diapause-like mechanisms will shed light on pathways steer through adverse conditions. One hope understanding support might be leveraged extend and/or health span humans as well species threatened by climate change. In addition, recent findings suggest cancer cells persist after treatment mimic states, implying these programs may facilitate from chemotherapy cause relapse. Here, we review underlying variety organisms, discuss supporting tumor persister cells.

Язык: Английский

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Synaptic connectome of the Drosophila circadian clock

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Дек. 5, 2024

Abstract The circadian clock and its output pathways play a pivotal role in optimizing daily processes. To obtain insights into how diverse rhythmic physiology behaviors are orchestrated, we have generated comprehensive connectivity map of an animal using the Drosophila FlyWire brain connectome. Intriguingly, identified additional dorsal neurons, thus showing that network contains ~240 instead 150 neurons. We revealed extensive contralateral synaptic within discovered novel indirect light input to also elucidated via which modulates descending neurons known regulate feeding reproductive behaviors. Interestingly, observed sparse monosynaptic between downstream higher-order centers neurosecretory cells behavior physiology. Therefore, integrated single-cell transcriptomics receptor mapping decipher putative paracrine peptidergic signaling by Our analyses neuropeptides expressed suggest significantly enriches interconnectivity network.

Язык: Английский

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Synaptic connectome of theDrosophilacircadian clock

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Сен. 13, 2023

The circadian clock and its output pathways play a pivotal role in optimizing daily processes. To obtain novel insights into how diverse rhythmic physiology behaviors are orchestrated, we have generated the first comprehensive connectivity map of an animal using Drosophila FlyWire brain connectome. Intriguingly, identified additional dorsal neurons, thus showing that network contains ∼240 instead 150 neurons. We also revealed extensive contralateral synaptic within discovered indirect light input to Interestingly, observed sparse monosynaptic between neurons down-stream higher-order centers neurosecretory cells known regulate behavior physiology. Therefore, integrated single-cell transcriptomics receptor mapping decipher putative paracrine peptidergic signaling by Our analyses neuropeptides expressed suggest significantly enriches interconnectivity network.

Язык: Английский

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Altered circadian rhythm, sleep, and rhodopsin 7 –dependent shade preference during diapause in Drosophila melanogaster

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(27)

Опубликована: Июнь 25, 2024

To survive adverse environments, many animals enter a dormant state such as hibernation, dauer, or diapause. Various Drosophila species undergo adult reproductive diapause in response to cool temperatures and/or short day-length. While flies are less active during diapause, it is unclear how environmental conditions affect circadian rhythms and sleep. Here we show that diapause-inducing temperatures, melanogaster exhibit altered activity profiles, including severely reduced morning an advanced evening peak. Consequently, the have single peak at time similar when nondiapausing take siesta. Temperatures ≤15 °C, rather than photoperiod, primarily drive this behavior. At rapidly deep-sleep lacks sleep cycles of higher require high levels stimulation for arousal. Furthermore, 25 prefer siesta shade, preference virtually eliminated 10 °C. Resting shade driven by aversion blue light sensed Rhodopsin 7 outside eyes. Flies °C neuronal markers elevated pressure, increased expression Bruchpilot Ca 2+ R5 ellipsoid body neurons. Therefore, pressure might overcome aversion. Thus, same cause arrest, preserve germline stem cells, extend lifespan, D. prone deep dramatically altered, yet rhythmic, daily patterns.

Язык: Английский

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Melatonin and Seasonal Synchrony in Mammals

Journal of Pineal Research, Год журнала: 2024, Номер 76(5)

Опубликована: Авг. 1, 2024

ABSTRACT In mammals, seasonal opportunities and challenges are anticipated through programmed changes in physiology behavior. Appropriate anticipatory timing depends on synchronization to the external solar year, achieved use of day length (photoperiod) as a synchronizing signal. nocturnal production melatonin by pineal gland is key hormonal mediator photoperiodic change, exerting its effects via hypothalamopituitary axis. this review/perspective, we consider developments during history research into synchronizer effect melatonin, highlighting role that pars tuberalis –tanycyte module plays process. We go downstream pathways, which include discrete hypothalamic neuronal populations. Neurons express neuropeptides kisspeptin (Arg)(Phe)–related peptide‐3 (RFRP‐3) govern reproductive function while neurons somatostatin may be involved metabolic adaptations. Finally, identify several outstanding questions, need addressed provide much thorough understanding deep impact upon synchronization.

Язык: Английский

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Photoperiodic plasticity of pigment-dispersing factor immunoreactive fibers projecting toward prothoracicotropic hormone neurons in flesh fly Sarcophaga similis larvae

Journal of Comparative Physiology A, Год журнала: 2025, Номер unknown

Опубликована: Янв. 15, 2025

Larvae of the flesh fly, Sarcophaga similis exhibit photoperiodic responses to control pupal diapause. Although external coincidence model is applicable S. photoperiodism, it remains unknown how circadian clock system integrates day-length information. To explore mechanisms, we examined neural circuitry involving lateral neurons (LNs) and prothoracicotropic hormone (PTTH) neurons. We also effects on LN-fiber patterns in third-instar larvae. Immunohistochemistry showed that protein PERIOD neuropeptide pigment-dispersing factor (PDF) were co-localized four cells per brain hemisphere, named these PDF-LNs similis. Single-cell polymerase chain reaction backfilled from ring gland two pairs pars lateralis with contralateral axons (PL-c neurons) expressed ptth. Double labeling immunohistochemistry backfills revealed PDF-immunoreactive varicose fibers projected close PL-c short f (snpf) receptor glutamate-gated chloride channel but not pdf sNPF L-glutamate PDF acutely inhibited spontaneous firing activity The number varicosities dorsal protocerebrum was significantly higher under short-day than long-day conditions a time-dependent manner. These results suggest and/or glutamate signaling PTTH form potential circuity for diapause photoperiod modifies connectivity strength between their post- or pre-neurons circuitry.

Язык: Английский

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Circadian Rhythm, Hypoxia, and Cellular Senescence: From Molecular Mechanisms to Targeted Strategies

European Journal of Pharmacology, Год журнала: 2025, Номер unknown, С. 177290 - 177290

Опубликована: Янв. 1, 2025

Язык: Английский

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Synaptic Targets of Circadian Clock Neurons Influence Core Clock Parameters

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2025, Номер unknown

Опубликована: Янв. 31, 2025

Neuronal connectivity in the circadian clock network is essential for robust endogenous timekeeping. In Drosophila network, four pairs of small ventral lateral neurons (sLNvs) serve as main pacemakers. Peptidergic communication via sLNv, which release key output neuropeptide, Pigment Dispersing Factor (PDF), has been well characterized. absence PDF, flies become largely arrhythmic, similar to phenotype associated with loss mammalian peptide, VIP. contrast, little known about role synaptic connections that sLNvs form downstream neurons. Connectomic analyses revealed despite their pacemaker within very few monosynaptic other However, they strong a group previously uncharacterized neurons, SLP316, turn synapse onto dorsal Here, we show silencing SLP316 tetanus toxin (TNT) expression shortens free-running period, whereas hyper-exciting them by expressing constitutively open Na[+] channel, NaChBac, results period lengthening. Under light-dark cycles, also causes lower daytime activity and higher sleep, likely due increased sleep pressure. Our postsynaptic partners are non-clock neuronal cell type regulates timing activity.

Язык: Английский

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A genome-wide association study implicates the olfactory system in Drosophila melanogaster diapause-associated lifespan extension and fecundity

Опубликована: Фев. 26, 2025

The effects of environmental stress on animal life are gaining importance with climate change. Diapause is a dormancy program that occurs in response to an adverse environment, followed by resumption development and reproduction upon the return favorable conditions. complex trait, so we leveraged Drosophila genetic reference panel (DGRP) lines conducted Genome-Wide Association Study (GWAS) characterize basis diapause. We assessed post-diapause non-diapause fecundity across 193 DGRP lines. GWAS revealed 546 variants, encompassing single nucleotide polymorphisms, insertions deletions associated fecundity. identified 291 candidate diapause-associated genes, 40 which had previously been diapause, 89 were more than one SNP. Gene network analysis indicated genes primarily linked neuronal reproductive system development. Similarly, comparison results from other fly greatest overlap olfactory-behavior-associated fecundity-and-lifespan-associated genes. An RNAi screen selected candidates two Dip-𝛾 Scribbler, be required during recovery for complemented test neurons successful found although amputation antenna little no effect lifespan, it reduced diapause lifespan postdiapause further show olfactory receptor temperature-sensing Our provide insights into molecular, cellular, adult .

Язык: Английский

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Pigment-dispersing factor neuropeptides act as multifunctional hormones and modulators in tardigrades

Open Biology, Год журнала: 2025, Номер 15(3)

Опубликована: Март 1, 2025

Pigment-dispersing factors (PDFs) are neuropeptides that play key roles in controlling the circadian rhythms various insects, whereas their function remains elusive other protostomes including tardigrades (water bears). Here we show three PDFs of tardigrade Hypsibius exemplaris co-localized two pairs inner lobe cells brain, only one PDF occurs four additional cerebral and extracerebral cells. The axons pass through contralateral brain hemisphere, descend to ventral nerve cord terminate potential release sites posteriormost trunk ganglion. Using vitro assays, demonstrate all deorphanized receptor (PDFR) functional. Widespread localization PDFR suggests may act as multifunctional hormones neuromodulators control major functions light detection, neural processing, locomotion, feeding, digestion, osmoregulation, growth, embryonic development oogenesis/reproduction.

Язык: Английский

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