Neuropeptidergic regulation of insect diapause by the circadian clock

Current Opinion in Insect Science, Journal Year: 2024, Volume and Issue: 63, P. 101198 - 101198

Published: April 6, 2024

Diapause is an endocrine-mediated strategy used by insects to survive seasons of adverse environmental conditions. Insects living in temperate zones are regularly exposed such conditions the form winter. To winter, they must prepare for it long before arrives. A reliable indicator impending winter shortening day length. measure length, need their circadian clock as internal time reference. In this article, I provide overview current state knowledge on neuropeptides that link diapause inducing hormonal brain centers.

Language: Английский

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A clock for all seasons

Journal of Comparative Physiology A, Journal Year: 2024, Volume and Issue: 210(4), P. 473 - 480

Published: June 19, 2024

Abstract Circadian clocks play an essential role in adapting locomotor activity as well physiological, and metabolic rhythms of organisms to the day-night cycles on Earth during four seasons. In addition, they can serve a time reference for measuring day length adapt advance annual changes environment, which be particularly pronounced at higher latitudes. The physiological responses are also known photoperiodism. This special issue Journal Comparative Physiology A aims account diurnal photoperiodic adaptations by presenting collection ten review articles, five original research three perspective pieces. contributions include historical accounts, circadian clock models, epigenetic, molecular, neuronal mechanisms seasonal adaptations, latitudinal differences studies wild that address challenges global change.

Language: Английский

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Circadian and circatidal oscillations of clock gene expression in brains of Eurydice pulchra and Parhyale hawaiensis.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract Coastal organisms express daily and tidal rhythms of physiology behaviour to adapt their intertidal environments. Although the molecular-genetic basis circadian clocks driving is well understood, nature mechanism circatidal remain a mystery. Using fluorescent in situ hybridisation, we mapped discrete clusters putative “clock” cells co-expressing canonical clock genes across brains crustaceans Eurydice pulchra Parhyale hawaiensis . Tidally rhythmic, field-collected E. exhibited ∼12-hour ∼24-hours gene expression cell groups. Laboratory-reared P. entrained 24-hour light:dark cycles (LD) exhibiting robust several In showing following entrainment by agitation under LD, was evident some rhythmic groups, but dorsal-lateral cluster ∼12-hour, i.e., circatidal, transcriptional rhythms. This oscillation phased prior agitation, not LD. These brain networks groups with or periodicities tracking LD respectively, reveal neural substrate for interactive generation appropriate complex habitats.

Language: Английский

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

Open Biology, Journal Year: 2025, Volume and Issue: 15(3)

Published: March 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.

Language: Английский

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Correlation between circadian and photoperiodic latitudinal clines in Drosophila littoralis

Open Biology, Journal Year: 2025, Volume and Issue: 15(3)

Published: March 1, 2025

Insects can survive harsh conditions, including Arctic winters, by entering a hormonally induced state of dormancy, known as diapause. Diapause is triggered environmental cues such shortening the photoperiod (lengthening night). The time entry into diapause depends on latitude insects' habitat, and this applies even within species: populations living at higher latitudes enter earlier in year than lower latitudes. A long-standing question biology whether internal circadian clock, which governs daily behaviour serves reference clock to measure night length, shows similar latitudinal adaptations. To address question, we examined onset various behavioural molecular parameters cosmopolitan fly, Drosophila littoralis, species distributed throughout Europe from Black Sea (41° N) regions (69° N). We found that all showed same correlation with critical length for induction. conclude has adapted may result observed differences

Language: Английский

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Pigment-dispersing factor is present in circadian clock neurons of pea aphids and may mediate photoperiodic signalling to insulin-producing cells

Open Biology, Journal Year: 2023, Volume and Issue: 13(6)

Published: June 1, 2023

The neuropeptide pigment-dispersing factor (PDF) plays a pivotal role in the circadian clock of most Ecdysozoa and is additionally involved timing seasonal responses several photoperiodic species. pea aphid, Acyrthosiphon pisum, paradigmatic species with an annual life cycle tightly coupled to changes day length. Nevertheless, PDF could not be identified A. pisum so far . In present study, we PDF-coding gene that has undergone significant otherwise highly conserved insect C-terminal amino acid sequence. A newly generated aphid-specific antibody stained four neurons each hemisphere aphid brain co-express protein Period have projections pars lateralis are plastic change their appearance daily manner, resembling those fruit fly neurons. Most intriguingly, terminals overlap dendrites insulin-like peptide (ILP) positive neurosecretory cells intercerebralis putative Cryptochrome (CRY) Since ILP been previously shown crucial for adaptations CRY might serve as photoreceptor vital measuring length, our results suggest critical timing.

Language: Английский

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The circadian and photoperiodic clock of the pea aphid

Journal of Comparative Physiology A, Journal Year: 2023, Volume and Issue: 210(4), P. 627 - 639

Published: July 24, 2023

The pea aphid, Acyrthosiphon pisum, is a paradigmatic photoperiodic species that exhibits remarkable annual life cycle, which tightly coupled to the seasonal changes in day length. During spring and summer, characterised by longer days, aphid populations consist exclusively of viviparous females reproduce parthenogenetically. When autumn comes days shorten, aphids switch their reproductive mode generate males oviparous sexual females, mate produce cold-resistant eggs overwinter survive unfavourable season. While responses have been well described, nature timing mechanisms underlie length discrimination are still not completely understood. Experiments from 1960's suggested rely on an 'hourglass' clock measuring elapsed time during dark night accumulating biochemical factor, reaches critical threshold at certain triggers reproduction mode. However, can also be attributed strongly dampened circadian clock. Recent studies uncovered molecular components location brain revealed it connected neurohormonal system controlling reproduction. We provide overview putative control aphids, photoreceptors involved this process neuroendocrine system.

Language: Английский

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The Never Given 2022 Pittendrigh/Aschoff Lecture: The Clock Network in the Brain—Insights From Insects

Journal of Biological Rhythms, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 11, 2024

My journey into chronobiology began in 1977 with lectures and internships Wolfgang Engelmann Hans Erkert at the University of Tübingen Germany. At that time, only known animal clock gene was

Language: Английский

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One seasonal clock fits all?

Journal of Comparative Physiology A, Journal Year: 2023, Volume and Issue: 210(4), P. 641 - 647

Published: Nov. 10, 2023

Adaptation of physiology and behavior to seasonal changes in the environment are for many organisms essential survival. Most our knowledge about underlying mechanisms comes from research on photoperiodic regulation reproduction plants, insects mammals. However, even humans, who mostly live environments with minimal influences, show annual rhythms (e.g., immune activity, brain function), sleep-wake cycles) disease prevalence infectious diseases). As variations environmental conditions may be drastically altered due climate change, understanding adaptation becomes more relevant. While species have developed specific solutions dedicated tasks regulation, we find a number common principles when comparing insect mammalian systems: (1) circadian system contributes regulation; (2) similar signaling molecules (VIP PDF) used transferring information neuroendocrine controlling response; (3) hormone melatonin participates as well mammals; (4) photoperiod affect neurotransmitter function both animal groups. The few examples overlap elaborated this perspective article, discussion relevance should seen encouragement unravel machinery multitude organisms.

Language: Английский

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Functional interactions between neurotransmitters and neuropeptides in regulating suprachiasmatic nucleus function and circadian rhythms

Exploration of neuroscience, Journal Year: 2024, Volume and Issue: 3(5), P. 434 - 477

Published: Sept. 24, 2024

The overt expression of circadian rhythms is a manifestation the suprachiasmatic nucleus (SCN). This integrated complex function based on transcriptional/translational feedback loops (TFFLs), neurotransmitters, genes, networking, and synchronization essential for this molecular mechanism to operate effectively. Neurotransmitters by participating in entrainment environmental light conditions contribute robustness rhythm. Neurotransmitter signaling hallmark rhythm expression. Even during development, neuropeptides dramatic cellular, genetic, network circuit changes. Participating neurotransmitters are seen afferent inputs, efferent output, SCN. There numerous involved SCN function. Astrocytes co-exist with neurons Autonomous clocks astrocytes can drive behavior like neurons. acting as two arms clock. Coupling through glutamate released from gives additional evidence role astrocytes. Glutaminergic may also be responsible timekeeping. independently combination execute functions making unique pacemaker rhythms. reassessment highlights its underlying mechanisms, genetic linkage, recently known

Language: Английский

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