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Sekiguchi M, Reinhard N, Fukuda A, Katoh S, Rieger D, Helfrich-Förster C, Yoshii T. A Detailed Re-Examination of the Period Gene Rescue Experiments Shows That Four to Six Cryptochrome-Positive Posterior Dorsal Clock Neurons (DN 1p) of Drosophila melanogaster Can Control Morning and Evening Activity. J Biol Rhythms 2024; 39:463-483. [PMID: 39082442 DOI: 10.1177/07487304241263130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024]
Abstract
Animal circadian clocks play a crucial role in regulating behavioral adaptations to daily environmental changes. The fruit fly Drosophila melanogaster exhibits 2 prominent peaks of activity in the morning and evening, known as morning (M) and evening (E) peaks. These peaks are controlled by 2 distinct circadian oscillators located in separate groups of clock neurons in the brain. To investigate the clock neurons responsible for the M and E peaks, a cell-specific gene expression system, the GAL4-UAS system, has been commonly employed. In this study, we re-examined the two-oscillator model for the M and E peaks of Drosophila by utilizing more than 50 Gal4 lines in conjunction with the UAS-period16 line, which enables the restoration of the clock function in specific cells in the period (per) null mutant background. Previous studies have indicated that the group of small ventrolateral neurons (s-LNv) is responsible for controlling the M peak, while the other group, consisting of the 5th ventrolateral neuron (5th LNv) and the three cryptochrome (CRY)-positive dorsolateral neurons (LNd), is responsible for the E peak. Furthermore, the group of posterior dorsal neurons 1 (DN1p) is thought to also contain M and E oscillators. In this study, we found that Gal4 lines directed at the same clock neuron groups can lead to different results, underscoring the fact that activity patterns are influenced by many factors. Nevertheless, we were able to confirm previous findings that the entire network of circadian clock neurons controls M and E peaks, with the lateral neurons playing a dominant role. In addition, we demonstrate that 4 to 6 CRY-positive DN1p cells are sufficient to generate M and E peaks in light-dark cycles and complex free-running rhythms in constant darkness. Ultimately, our detailed screening could serve as a catalog to choose the best Gal4 lines that can be used to rescue per in specific clock neurons.
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Affiliation(s)
- Manabu Sekiguchi
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Nils Reinhard
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Ayumi Fukuda
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Shun Katoh
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Okayama, Japan
| | - Dirk Rieger
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Taishi Yoshii
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Okayama, Japan
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2
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Chakravarty P, Ashbury AM, Strandburg-Peshkin A, Iffelsberger J, Goldshtein A, Schuppli C, Snell KRS, Charpentier MJE, Núñez CL, Gaggioni G, Geiger N, Rößler DC, Gall G, Yang PP, Fruth B, Harel R, Crofoot MC. The sociality of sleep in animal groups. Trends Ecol Evol 2024:S0169-5347(24)00176-9. [PMID: 39242333 DOI: 10.1016/j.tree.2024.07.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 07/15/2024] [Accepted: 07/19/2024] [Indexed: 09/09/2024]
Abstract
Group-living animals sleep together, yet most research treats sleep as an individual process. Here, we argue that social interactions during the sleep period contribute in important, but largely overlooked, ways to animal groups' social dynamics, while patterns of social interaction and the structure of social connections within animal groups play important, but poorly understood, roles in shaping sleep behavior. Leveraging field-appropriate methods, such as direct and video-based observation, and increasingly common on-animal motion sensors (e.g., accelerometers), behavioral indicators can be tracked to measure sleep in multiple individuals in a group of animals simultaneously. Sleep proximity networks and sleep timing networks can then be used to investigate the collective dynamics of sleep in wild group-living animals.
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Affiliation(s)
- Pritish Chakravarty
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany.
| | - Alison M Ashbury
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Ariana Strandburg-Peshkin
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Josefine Iffelsberger
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Aya Goldshtein
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany; Department of Collective Behavior, Max Planck Institute of Animal Behavior, Konstanz, Germany
| | - Caroline Schuppli
- Development and Evolution of Cognition Research Group, Max Planck Institute of Animal Behavior, Konstanz, Germany
| | - Katherine R S Snell
- Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Migration, Max Planck Institute of Animal Behavior, Konstanz, Germany
| | - Marie J E Charpentier
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Institut des Sciences de l'Evolution de Montpellier (ISEM), UMR5554, University of Montpellier/CNRS/IRD/EPHE, Montpellier, France
| | - Chase L Núñez
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Giulia Gaggioni
- Institut des Sciences de l'Evolution de Montpellier (ISEM), UMR5554, University of Montpellier/CNRS/IRD/EPHE, Montpellier, France; Division of Psychiatry, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Nadja Geiger
- Department of Biology, University of Konstanz, Konstanz, Germany; Zukunftskolleg, University of Konstanz, Konstanz, Germany
| | - Daniela C Rößler
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany; Zukunftskolleg, University of Konstanz, Konstanz, Germany
| | - Gabriella Gall
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany; Zukunftskolleg, University of Konstanz, Konstanz, Germany
| | - Pei-Pei Yang
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; School of Resources and Environmental Engineering, Anhui University, Hefei, China; International Collaborative Research Center for Huangshan Biodiversity and Tibetan Macaque Behavioral Ecology, Hefei, China
| | - Barbara Fruth
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Department of Migration, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for Research and Conservation/KMDA, Antwerp, Belgium
| | - Roi Harel
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany
| | - Margaret C Crofoot
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany; Department of Biology, University of Konstanz, Konstanz, Germany.
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3
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Benita M, Menahem A, Rath A, Scharf I, Gottlieb D. Beyond adult models: Tribolium castaneum larval timekeeping reveals unexpected robustness and insights into circadian clock. INSECT SCIENCE 2024. [PMID: 39126186 DOI: 10.1111/1744-7917.13437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 07/03/2024] [Accepted: 07/09/2024] [Indexed: 08/12/2024]
Abstract
Circadian rhythms are self-sustained endogenous oscillations that are found in all living organisms. In insects, circadian rhythms control a wide variety of behavioral and physiological processes, including feeding, locomotion, mating, and metabolism. While the role of circadian rhythms in adult insects is well-understood, it is largely unexplored in larvae. This study investigates the potential for larval synchronized activity in the red flour beetle (Tribolium castaneum), a species exhibiting solitary and aggregation phases. We hypothesized that, similar to adults, larvae would exhibit a daily activity pattern governed by an endogenous circadian clock. We further predicted that the transition between the solitary and gregarious phases extends to unique temporal activity patterns. Our results revealed unique timekeeper gene expression in larvae, leading to a distinct daily rhythm characterized by nocturnal activity. Cues indicating on potential cannibalism did not change daily activity peak. However, the absence of these cues significantly reduced the proportion of rhythmic larvae and led to higher variation in peak activity, highlighting the crucial role of social interactions in shaping their rhythmicity. This study sheds light on the evolution and function of larval synchronization in group-living insects, offering novel insights into this complex behavior.
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Affiliation(s)
- Miriam Benita
- Department of Food Science, Institute of Post-Harvest and Food Science, The Volcani Center, Rishon LeZion, Israel
- George S Wise Faculty of Life Sciences, School of Zoology, Tel Aviv University, Tel Aviv, Israel
| | - Ariel Menahem
- Department of Food Science, Institute of Post-Harvest and Food Science, The Volcani Center, Rishon LeZion, Israel
| | - Animesha Rath
- Department of Food Science, Institute of Post-Harvest and Food Science, The Volcani Center, Rishon LeZion, Israel
| | - Inon Scharf
- George S Wise Faculty of Life Sciences, School of Zoology, Tel Aviv University, Tel Aviv, Israel
| | - Daphna Gottlieb
- Department of Food Science, Institute of Post-Harvest and Food Science, The Volcani Center, Rishon LeZion, Israel
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Vaze KM, Manoli G, Helfrich-Förster C. Drosophila ezoana uses morning and evening oscillators to adjust its rhythmic activity to different daylengths but only the morning oscillator to measure night length for photoperiodic responses. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:535-548. [PMID: 37329349 PMCID: PMC11226516 DOI: 10.1007/s00359-023-01646-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/11/2023] [Accepted: 05/30/2023] [Indexed: 06/19/2023]
Abstract
Animals living at high latitudes are exposed to prominent seasonal changes to which they need to adapt to survive. By applying Zeitgeber cycles of different periods and photoperiods we show here that high-latitude D. ezoana flies possess evening oscillators and highly damped morning oscillators that help them adapting their activity rhythms to long photoperiods. In addition, the damped morning oscillators are involved in timing diapause. The flies measure night length and use external coincidence for timing diapause. We discuss the clock protein TIMELESS (d-TIM) as the molecular correlate and the small ventrolateral clock neurons (s-LNvs) as the anatomical correlates of the components measuring night length.
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Affiliation(s)
- Koustubh M Vaze
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Giulia Manoli
- Neurobiology and Genetics, University of Würzburg, Biocentre, Theodor-Boveri-Institute, Am Hubland, 97074, Würzburg, Germany
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, University of Würzburg, Biocentre, Theodor-Boveri-Institute, Am Hubland, 97074, Würzburg, Germany.
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5
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Bidell D, Feige ND, Triphan T, Müller C, Pauls D, Helfrich-Förster C, Selcho M. Photoreceptors for immediate effects of light on circadian behavior. iScience 2024; 27:109819. [PMID: 38770135 PMCID: PMC11103378 DOI: 10.1016/j.isci.2024.109819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 03/12/2024] [Accepted: 04/24/2024] [Indexed: 05/22/2024] Open
Abstract
Animals need to sharpen their behavioral output in order to adapt to a variable environment. Hereby, light is one of the most pivotal environmental signals and thus behavioral plasticity in response to light can be observed in diurnal animals, including humans. Furthermore, light is the main entraining signal of the clock, yet immediate effects of light enhance or overwrite circadian output and thereby mask circadian behavior. In Drosophila, such masking effects are most evident as a lights-on response in two behavioral rhythms - the emergence of the adult insect from the pupa, called eclosion, and the diurnal rhythm of locomotor activity. Here, we show that the immediate effect of light on eclosion depends solely on R8 photoreceptors of the eyes. In contrast, the increase in activity by light at night is triggered by different cells and organs that seem to compensate for the loss of each other, potentially to ensure behavioral plasticity.
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Affiliation(s)
- Daniel Bidell
- Department of Animal Physiology, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Natalie-Danielle Feige
- Department of Animal Physiology, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Tilman Triphan
- Department of Genetics, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Claudia Müller
- Department of Animal Physiology, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Dennis Pauls
- Department of Animal Physiology, Institute of Biology, Leipzig University, Leipzig, Germany
| | | | - Mareike Selcho
- Department of Animal Physiology, Institute of Biology, Leipzig University, Leipzig, Germany
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6
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Amatobi KM, Ozbek-Unal AG, Schäbler S, Deppisch P, Helfrich-Förster C, Mueller MJ, Wegener C, Fekete A. The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition. J Lipid Res 2023; 64:100417. [PMID: 37481037 PMCID: PMC10550813 DOI: 10.1016/j.jlr.2023.100417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 07/06/2023] [Accepted: 07/11/2023] [Indexed: 07/24/2023] Open
Abstract
Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period01 clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality.
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Affiliation(s)
- Kelechi M Amatobi
- Biocenter, Julius-von-Sachs-Institute, Pharmaceutical Biology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany; Biocenter, Theodor-Boveri-Institute, Würzburg Insect Research (WIR), Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Ayten Gizem Ozbek-Unal
- Biocenter, Julius-von-Sachs-Institute, Pharmaceutical Biology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Stefan Schäbler
- Biocenter, Julius-von-Sachs-Institute, Pharmaceutical Biology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Peter Deppisch
- Biocenter, Theodor-Boveri-Institute, Würzburg Insect Research (WIR), Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Charlotte Helfrich-Förster
- Biocenter, Theodor-Boveri-Institute, Würzburg Insect Research (WIR), Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Martin J Mueller
- Biocenter, Julius-von-Sachs-Institute, Pharmaceutical Biology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Christian Wegener
- Biocenter, Theodor-Boveri-Institute, Würzburg Insect Research (WIR), Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.
| | - Agnes Fekete
- Biocenter, Julius-von-Sachs-Institute, Pharmaceutical Biology, Julius-Maximilians-Universität Würzburg, Würzburg, Germany.
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7
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Silva-López J, Godoy P, Jara L, Godoy-Herrera R. Interaction and integration among behaviors of adult Drosophila in nature. PLoS One 2023; 18:e0278427. [PMID: 37440503 PMCID: PMC10343093 DOI: 10.1371/journal.pone.0278427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 06/23/2023] [Indexed: 07/15/2023] Open
Abstract
Living in environments whose ecologies vary in periods as short as 24 h is a challenge for animals as Drosophila species that inhabit pear and apple orchards. These orchards have sunny and shady sections. The size and shape of these habitats change daily according to the position of the sun in the sky. Sunny areas are related to dryness and water loss, and shady places have lower temperatures and higher humidity. The presence of heterospecific flies may lead to competition for space and food. In sunny habitats we did not find adult Drosophila. In shady sections we found conspecific groups D. melanogaster, D. simulans, D. immigrans, D. subobscura, and the Chilean endemic D. pavani perched on grasses and herbs at 8-10 cm from fruits that had fallen on the ground. In the fruits, 99% of the adults were females and they were not grouped. The way in which daily changes in the size and shape of shady habitats together with the presence of heterospecific adults influence the selection of places to live is poorly understood in Drosophila. Our experiments show that adults of the five species prefer dark areas. The experimental results show that the odors of each species: i) influence conspecifics to select similar perch sites and decrease mobility, and ii) increase mobility in heterospecific adults and modify their perch site preferences. Attractions between conspecifics, the repulsions between species, and preferences for shaded areas matter in choosing a place to live in the five Drosophila species. These behaviors seem to have evolved as coordinated routines, contributing to the coexistence of the five Drosophila species in the apple and pear orchards examined.
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Affiliation(s)
- Jeannette Silva-López
- Facultad de Ciencias, Departamento de Ciencias Básicas, Universidad del Bío-Bío, Chillán, Chile
| | - Pablo Godoy
- Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Canada
| | - Lilian Jara
- Facultad de Medicina, Programa de Genética Humana, Universidad de Chile, Santiago, Chile
| | - Raúl Godoy-Herrera
- Facultad de Medicina, Programa de Genética Humana, Universidad de Chile, Santiago, Chile
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Au DD, Liu JC, Park SJ, Nguyen TH, Dimalanta M, Foden AJ, Holmes TC. Drosophila photoreceptor systems converge in arousal neurons and confer light responsive robustness. Front Neurosci 2023; 17:1160353. [PMID: 37274190 PMCID: PMC10235467 DOI: 10.3389/fnins.2023.1160353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/05/2023] [Indexed: 06/06/2023] Open
Abstract
Lateral ventral neurons (LNvs) in the fly circadian neural circuit mediate behaviors other than clock resetting, including light-activated acute arousal. Converging sensory inputs often confer functional redundancy. The LNvs have three distinct light input pathways: (1) cell autonomously expressed cryptochrome (CRY), (2) rhodopsin 7 (Rh7), and (3) synaptic inputs from the eyes and other external photoreceptors that express opsins and CRY. We explored the relative photoelectrical and behavioral input contributions of these three photoreceptor systems to determine their functional impact in flies. Patch-clamp electrophysiology measuring light evoked firing frequency (FF) was performed on large LNvs (l-LNvs) in response to UV (365 nm), violet (405 nm), blue (450 nm), or red (635 nm) LED light stimulation, testing controls versus mutants that lack photoreceptor inputs gl60j, cry-null, rh7-null, and double mutant gl60j-cry-null flies. For UV, violet, and blue short wavelength light inputs, all photoreceptor mutants show significantly attenuated action potential FF responses measured in the l-LNv. In contrast, red light FF responses are only significantly attenuated in double mutant gl60j-cry-null flies. We used a light-pulse arousal assay to compare behavioral responses to UV, violet, blue and red light of control and light input mutants, measuring the awakening arousal response of flies during subjective nighttime at two different intensities to capture potential threshold differences (10 and 400 μW/cm2). The light arousal behavioral results are similar to the electrophysiological results, showing significant attenuation of behavioral light responses for mutants compared to control. These results show that the different LNv convergent photoreceptor systems are integrated and together confer functional redundancy for light evoked behavioral arousal.
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Affiliation(s)
- David D. Au
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Jenny C. Liu
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Soo Jee Park
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Thanh H. Nguyen
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Mia Dimalanta
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Alexander J. Foden
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
| | - Todd C. Holmes
- Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
- Center for Neural Circuit Mapping, School of Medicine, University of California, Irvine, Irvine, CA, United States
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9
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Wice EW, Saltz JB. Indirect genetic effects for social network structure in Drosophila melanogaster. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220075. [PMID: 36802774 PMCID: PMC9939268 DOI: 10.1098/rstb.2022.0075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/16/2022] [Indexed: 02/21/2023] Open
Abstract
The position an individual holds in a social network is dependent on both its direct and indirect social interactions. Because social network position is dependent on the actions and interactions of conspecifics, it is likely that the genotypic composition of individuals within a social group impacts individuals' network positions. However, we know very little about whether social network positions have a genetic basis, and even less about how the genotypic makeup of a social group impacts network positions and structure. With ample evidence indicating that network positions influence various fitness metrics, studying how direct and indirect genetic effects shape network positions is crucial for furthering our understanding of how the social environment can respond to selection and evolve. Using replicate genotypes of Drosophila melanogaster fruit flies, we created social groups that varied in their genotypic makeup. Social groups were videoed, and networks were generated using motion-tracking software. We found that both an individual's own genotype and the genotypes of conspecifics in its social group affect its position within a social network. These findings provide an early example of how indirect genetic effects and social network theory can be linked, and shed new light on how quantitative genetic variation shapes the structure of social groups. This article is part of a discussion meeting issue 'Collective behaviour through time'.
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Affiliation(s)
- Eric Wesley Wice
- Department of Biosciences, Rice University, Houston, TX 77005, USA
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10
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Kyriacou CP, Menegazzi P, Dolezel D. Editorial: Biological rhythms: Evolution, population biology, and adaptation. Front Physiol 2023; 14:1157631. [PMID: 36866177 PMCID: PMC9971991 DOI: 10.3389/fphys.2023.1157631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/16/2023] Open
Affiliation(s)
- Charalambos P. Kyriacou
- Department Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom,*Correspondence: Charalambos P. Kyriacou,
| | - Pamela Menegazzi
- Neurobiology and Genetics, University of Würzburg, Würzburg, Germany
| | - David Dolezel
- The Czech Academy of Sciences, AVCR, Institute of Entomology, Ceske Budejovice, Czechia
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11
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Jiang XL, Ren Z, Hai XX, Zhang L, Wang ZG, Lyu F. Exposure to artificial light at night mediates the locomotion activity and oviposition capacity of Dastarcus helophoroides (Fairmaire). Front Physiol 2023; 14:1063601. [PMID: 36846342 PMCID: PMC9947650 DOI: 10.3389/fphys.2023.1063601] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/31/2023] [Indexed: 02/11/2023] Open
Abstract
Light entrains the endogenous circadian clocks of organisms to synchronize their behavioral and physiological rhythms with the natural photoperiod. The presence of artificial light at night disrupts these photoperiodic cues and is currently considered to be a major threat to key fitness-related behaviors, including sleep disruption and physiological stress. Research on the ecological influence of forest pest and their natural enemies is lacking. The wood-boring insects significantly damage forest and urban forest ecosystem functions. The parasitic beetles, Dastarcus helophoroides is an important natural enemy of wood-boring insects, especially those in the Cerambycidae family. However, the effect of artificial light at night on the locomotor rhythms and oviposition capacity of D. helophoroides has received little attention. To address this gap, diel changes in the locomotor activity and number of eggs laid by female D. helophoroides was analyzed under different light-dark (LD) cycles and temperatures. The results showed that the 24-h rhythmic of locomotor activity in these beetles was elevated in darkness and reduced under illumination, indicating that they are nocturnal insects. This activity has two major peaks, the evening (1-8 h after lights off) and morning (3.5-12.5 h after lights off) components, reflecting that light mediate regular changes in locomotor activity. Moreover, the circadian rhythms and active percentage were influenced by the illumination duration and temperature, especially constant light and 40°C. Females laid more eggs under the 16 L: 8 D cycles at 30°C than under the other combinations of photoperiod (including constant light and darkness) and temperature. Finally, the potential influence of exposure to four ecologically relevant intensities of artificial light at night (0, 1, 10 or 100 lx) on oviposition capacity was studied. The results showed that lifetime exposure to bright artificial light (1-100 lx) at night decreased the number of eggs laid relative to those laid with no lighting at night. These results demonstrate that chronic exposure to bright artificial light at night may influence the locomotor activity and oviposition capacity of this parasitic beetle.
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Affiliation(s)
- Xiang-lan Jiang
- Key Laboratories for Germplasm Resources of Forest Trees and Forest Protection of Hebei Province, College of Forestry, Agricultural University of Hebei, Baoding, Hebei, China
| | - Zhe Ren
- Key Laboratories for Germplasm Resources of Forest Trees and Forest Protection of Hebei Province, College of Forestry, Agricultural University of Hebei, Baoding, Hebei, China
| | - Xiao-xia Hai
- Key Laboratories for Germplasm Resources of Forest Trees and Forest Protection of Hebei Province, College of Forestry, Agricultural University of Hebei, Baoding, Hebei, China
| | - Ling Zhang
- Chengde Academy of Agriculture and Forestry Sciences, Chengde, Hebei, China
| | - Zhi-gang Wang
- Key Laboratories for Germplasm Resources of Forest Trees and Forest Protection of Hebei Province, College of Forestry, Agricultural University of Hebei, Baoding, Hebei, China
| | - Fei Lyu
- Key Laboratories for Germplasm Resources of Forest Trees and Forest Protection of Hebei Province, College of Forestry, Agricultural University of Hebei, Baoding, Hebei, China,*Correspondence: Fei Lyu,
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12
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Liessem S, Held M, Bisen RS, Haberkern H, Lacin H, Bockemühl T, Ache JM. Behavioral state-dependent modulation of insulin-producing cells in Drosophila. Curr Biol 2023; 33:449-463.e5. [PMID: 36580915 DOI: 10.1016/j.cub.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 11/01/2022] [Accepted: 12/02/2022] [Indexed: 12/29/2022]
Abstract
Insulin signaling plays a pivotal role in metabolic control and aging, and insulin accordingly is a key factor in several human diseases. Despite this importance, the in vivo activity dynamics of insulin-producing cells (IPCs) are poorly understood. Here, we characterized the effects of locomotion on the activity of IPCs in Drosophila. Using in vivo electrophysiology and calcium imaging, we found that IPCs were strongly inhibited during walking and flight and that their activity rebounded and overshot after cessation of locomotion. Moreover, IPC activity changed rapidly during behavioral transitions, revealing that IPCs are modulated on fast timescales in behaving animals. Optogenetic activation of locomotor networks ex vivo, in the absence of actual locomotion or changes in hemolymph sugar levels, was sufficient to inhibit IPCs. This demonstrates that the behavioral state-dependent inhibition of IPCs is actively controlled by neuronal pathways and is independent of changes in glucose concentration. By contrast, the overshoot in IPC activity after locomotion was absent ex vivo and after starvation, indicating that it was not purely driven by feedforward signals but additionally required feedback derived from changes in hemolymph sugar concentration. We hypothesize that IPC inhibition during locomotion supports mobilization of fuel stores during metabolically demanding behaviors, while the rebound in IPC activity after locomotion contributes to replenishing muscle glycogen stores. In addition, the rapid dynamics of IPC modulation support a potential role of insulin in the state-dependent modulation of sensorimotor processing.
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Affiliation(s)
- Sander Liessem
- Neurobiology and Genetics, Theodor-Boveri-Institute, Biocenter, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Martina Held
- Neurobiology and Genetics, Theodor-Boveri-Institute, Biocenter, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Rituja S Bisen
- Neurobiology and Genetics, Theodor-Boveri-Institute, Biocenter, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Hannah Haberkern
- HHMI Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Haluk Lacin
- Department of Genetics, Washington University School of Medicine, 4523 Clayton Avenue, St Louis, MO 63110, USA
| | - Till Bockemühl
- Department of Biology, Institute of Zoology, University of Cologne, Zülpicher Str. 47b, 50674 Cologne, Germany
| | - Jan M Ache
- Neurobiology and Genetics, Theodor-Boveri-Institute, Biocenter, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
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13
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Riva S, Ispizua JI, Breide MT, Polcowñuk S, Lobera JR, Ceriani MF, Risau-Gusman S, Franco DL. Mating disrupts morning anticipation in Drosophila melanogaster females. PLoS Genet 2022; 18:e1010258. [PMID: 36548223 PMCID: PMC9779042 DOI: 10.1371/journal.pgen.1010258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 11/04/2022] [Indexed: 12/24/2022] Open
Abstract
After mating, the physiology of Drosophila females undergo several important changes, some of which are reflected in their rest-activity cycles. To explore the hypothesis that mating modifies the temporal organization of locomotor activity patterns, we recorded fly activity by a video tracking method. Monitoring rest-activity patterns under light/dark (LD) cycles indicated that mated females lose their ability to anticipate the night-day transition, in stark contrast to males and virgins. This postmating response is mediated by the activation of the sex peptide receptor (SPR) mainly on pickpocket (ppk) expressing neurons, since reducing expression of this receptor in these neurons restores the ability to anticipate the LD transition in mated females. Furthermore, we provide evidence of connectivity between ppk+ neurons and the pigment-dispersing factor (PDF)-positive ventral lateral neurons (sLNv), which play a central role in the temporal organization of daily activity. Since PDF has been associated to the generation of the morning activity peak, we hypothesized that the mating signal could modulate PDF levels. Indeed, we confirm that mated females have reduced PDF levels at the dorsal protocerebrum; moreover, SPR downregulation in ppk+ neurons mimics PDF levels observed in males. In sum, our results are consistent with a model whereby mating-triggered signals reach clock neurons in the fly central nervous system to modulate the temporal organization of circadian behavior according to the needs of the new status.
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Affiliation(s)
- Sabrina Riva
- Medical Physics Department, Bariloche Atomic Center, Comisión Nacional de Energía Atómica (CNEA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Argentina
| | - Juan Ignacio Ispizua
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir—IIBBA—CONICET, Buenos Aires, Argentina
| | - María Trinidad Breide
- Medical Physics Department, Bariloche Atomic Center, Comisión Nacional de Energía Atómica (CNEA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Argentina
| | - Sofía Polcowñuk
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir—IIBBA—CONICET, Buenos Aires, Argentina
| | - José Ricardo Lobera
- Medical Physics Department, Bariloche Atomic Center, Comisión Nacional de Energía Atómica (CNEA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Argentina
| | - María Fernanda Ceriani
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir—IIBBA—CONICET, Buenos Aires, Argentina
| | - Sebastian Risau-Gusman
- Medical Physics Department, Bariloche Atomic Center, Comisión Nacional de Energía Atómica (CNEA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Argentina
- * E-mail: (SRG); (DLF)
| | - Diana Lorena Franco
- Medical Physics Department, Bariloche Atomic Center, Comisión Nacional de Energía Atómica (CNEA) and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Argentina
- * E-mail: (SRG); (DLF)
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14
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Dani C, Sheeba V. Drosophila Populations Reared Under Tropical Semi-natural Conditions Evolve Season-dependent Differences in Timing of Eclosion. Front Physiol 2022; 13:954731. [PMID: 35910567 PMCID: PMC9334559 DOI: 10.3389/fphys.2022.954731] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 06/15/2022] [Indexed: 11/16/2022] Open
Abstract
Circadian clocks are considered an evolutionary adaptation to environmental cycles, helping organisms to adapt to daily and seasonal changes. However, most studies on the evolution of circadian rhythms have been carried out in controlled laboratory conditions; hence evolution of circadian clocks and rhythms in organisms reared under the influence of naturally varying time cues is not well understood. To address this, we reared large outbred fly populations in an outdoor enclosure on our institutional grounds in Bengaluru, southern India for about 150 generations, at the same time maintaining their ancestral control populations under standard laboratory conditions. Studying their rhythms in eclosion, a vital behavior for Drosophila, in the laboratory and semi-natural environments revealed that flies reared under semi-natural conditions differed in the timing of eclosion under semi-natural conditions in a season-dependent manner from their laboratory-reared counterparts. These differences were manifested under harsh semi-natural environments but not under mild ones or in standard laboratory conditions. Further analysis revealed that this phenotype might be responsive to seasonal changes in temperature cycles which was confirmed in the laboratory with simulated light and temperature cycles that approximated semi-natural conditions. Our results highlight key intricacies on the relative impact of intensity and timing of environmental cues for predicting the timing of Drosophila eclosion under tropical naturalistic conditions. Overall, our research uncovers previously unexplored aspects of adaptive circadian timekeeping in complex natural conditions, offering valuable insight into the evolution of clocks.
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15
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Zurl M, Poehn B, Rieger D, Krishnan S, Rokvic D, Veedin Rajan VB, Gerrard E, Schlichting M, Orel L, Ćorić A, Lucas RJ, Wolf E, Helfrich-Förster C, Raible F, Tessmar-Raible K. Two light sensors decode moonlight versus sunlight to adjust a plastic circadian/circalunidian clock to moon phase. Proc Natl Acad Sci U S A 2022; 119:e2115725119. [PMID: 35622889 PMCID: PMC9295771 DOI: 10.1073/pnas.2115725119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 03/31/2022] [Indexed: 11/30/2022] Open
Abstract
Many species synchronize their physiology and behavior to specific hours. It is commonly assumed that sunlight acts as the main entrainment signal for ∼24-h clocks. However, the moon provides similarly regular time information. Consistently, a growing number of studies have reported correlations between diel behavior and lunidian cycles. Yet, mechanistic insight into the possible influences of the moon on ∼24-h timers remains scarce. We have explored the marine bristleworm Platynereis dumerilii to investigate the role of moonlight in the timing of daily behavior. We uncover that moonlight, besides its role in monthly timing, also schedules the exact hour of nocturnal swarming onset to the nights’ darkest times. Our work reveals that extended moonlight impacts on a plastic clock that exhibits <24 h (moonlit) or >24 h (no moon) periodicity. Abundance, light sensitivity, and genetic requirement indicate that the Platynereis light receptor molecule r-Opsin1 serves as a receptor that senses moonrise, whereas the cryptochrome protein L-Cry is required to discriminate the proper valence of nocturnal light as either moonlight or sunlight. Comparative experiments in Drosophila suggest that cryptochrome’s principle requirement for light valence interpretation is conserved. Its exact biochemical properties differ, however, between species with dissimilar timing ecology. Our work advances the molecular understanding of lunar impact on fundamental rhythmic processes, including those of marine mass spawners endangered by anthropogenic change.
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Affiliation(s)
- Martin Zurl
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Birgit Poehn
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Dirk Rieger
- Department for Neurobiology and Genetics, Theodor-Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Shruthi Krishnan
- Institute of Molecular Biology, 55128 Mainz, Germany
- Institute of Molecular Physiology, Johannes Gutenberg-University of Mainz, 55128 Mainz, Germany
| | - Dunja Rokvic
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Vinoth Babu Veedin Rajan
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Elliot Gerrard
- Division of Neuroscience & Experimental Psychology, University of Manchester, Manchester M13 9PT, United Kingdom
| | | | - Lukas Orel
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Aida Ćorić
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Robert J. Lucas
- Division of Neuroscience & Experimental Psychology, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Eva Wolf
- Institute of Molecular Biology, 55128 Mainz, Germany
- Institute of Molecular Physiology, Johannes Gutenberg-University of Mainz, 55128 Mainz, Germany
| | - Charlotte Helfrich-Förster
- Department for Neurobiology and Genetics, Theodor-Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Florian Raible
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
| | - Kristin Tessmar-Raible
- Max Perutz Labs, University of Vienna, 1030 Vienna, Austria
- Research Platform “Rhythms of Life", University of Vienna, 1030 Vienna, Austria
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
- Carl-von-Ossietzky University, 26111 Oldenburg, Germany
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16
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Gupta P, Sinha A, Malik S, Rani S. Dawn and dusk chorus as a potential zeitgeber. BIOL RHYTHM RES 2022. [DOI: 10.1080/09291016.2022.2069646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Preeti Gupta
- Biological Rhythm Research Laboratory, Department of Zoology, University of Lucknow, Lucknow, India
| | - Ankit Sinha
- Biodiversity and Wildlife Conservation Laboratory, Department of Zoology, University of Lucknow, Lucknow, India
| | - Shalie Malik
- Biological Rhythm Research Laboratory, Department of Zoology, University of Lucknow, Lucknow, India
| | - Sangeeta Rani
- Department of Zoology, University of Lucknow, Lucknow, India
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17
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Iyengar AS, Kulkarni R, Sheeba V. Under warm ambient conditions, Drosophila melanogaster suppresses nighttime activity via the neuropeptide pigment dispersing factor. GENES, BRAIN, AND BEHAVIOR 2022; 21:e12802. [PMID: 35285135 PMCID: PMC9744560 DOI: 10.1111/gbb.12802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 02/21/2022] [Accepted: 02/21/2022] [Indexed: 11/26/2022]
Abstract
Rhythmic locomotor behaviour of flies is controlled by an endogenous time-keeping mechanism, the circadian clock, and is influenced by environmental temperatures. Flies inherently prefer cool temperatures around 25°C, and under such conditions, time their locomotor activity to occur at dawn and dusk. Under relatively warmer conditions such as 30°C, flies shift their activity into the night, advancing their morning activity bout into the early morning, before lights-ON, and delaying their evening activity into early night. The molecular basis for such temperature-dependent behavioural modulation has been associated with core circadian clock genes, but the neuronal basis is not yet clear. Under relatively cool temperatures such as 25°C, the role of the circadian pacemaker ventrolateral neurons (LNvs), along with a major neuropeptide secreted by them, pigment dispersing factor (PDF), has been showed in regulating various aspects of locomotor activity rhythms. However, the role of the LNvs and PDF in warm temperature-mediated behavioural modulation has not been explored. We show here that flies lacking proper PDF signalling or the LNvs altogether, cannot suppress their locomotor activity resulting in loss of sleep during the middle of the night, and thus describe a novel role for PDF signalling and the LNvs in behavioural modulation under warm ambient conditions. In a rapidly warming world, such behavioural plasticity may enable organisms to respond to harsh temperatures in the environment.
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Affiliation(s)
- Aishwariya Srikala Iyengar
- Chronobiology and Behavioural Neurogenetics LaboratoryNeuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBangaloreIndia
| | - Rutvij Kulkarni
- Chronobiology and Behavioural Neurogenetics LaboratoryNeuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBangaloreIndia
| | - Vasu Sheeba
- Chronobiology and Behavioural Neurogenetics LaboratoryNeuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBangaloreIndia
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18
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Perception of Daily Time: Insights from the Fruit Flies. INSECTS 2021; 13:insects13010003. [PMID: 35055846 PMCID: PMC8780729 DOI: 10.3390/insects13010003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/21/2021] [Accepted: 12/07/2021] [Indexed: 11/17/2022]
Abstract
We create mental maps of the space that surrounds us; our brains also compute time—in particular, the time of day. Visual, thermal, social, and other cues tune the clock-like timekeeper. Consequently, the internal clock synchronizes with the external day-night cycles. In fact, daylength itself varies, causing the change of seasons and forcing our brain clock to accommodate layers of plasticity. However, the core of the clock, i.e., its molecular underpinnings, are highly resistant to perturbations, while the way animals adapt to the daily and annual time shows tremendous biological diversity. How can this be achieved? In this review, we will focus on 75 pairs of clock neurons in the Drosophila brain to understand how a small neural network perceives and responds to the time of the day, and the time of the year.
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19
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Chromatin Dynamics and Gene Expression Response to Heat Exposure in Field-Conditioned versus Laboratory-Cultured Nematostella vectensis. Int J Mol Sci 2021; 22:ijms22147454. [PMID: 34299075 PMCID: PMC8303994 DOI: 10.3390/ijms22147454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/05/2021] [Accepted: 07/08/2021] [Indexed: 12/19/2022] Open
Abstract
Organisms’ survival is associated with the ability to respond to natural or anthropogenic environmental stressors. Frequently, these responses involve changes in gene regulation and expression, consequently altering physiology, development, or behavior. Here, we present modifications in response to heat exposure that mimics extreme summertime field conditions of lab-cultured and field-conditioned Nematostella vectensis. Using ATAC-seq and RNA-seq data, we found that field-conditioned animals had a more concentrated reaction to short-term thermal stress, expressed as enrichment of the DNA repair mechanism pathway. By contrast, lab animals had a more diffuse reaction that involved a larger number of differentially expressed genes and enriched pathways, including amino acid metabolism. Our results demonstrate that pre-conditioning affects the ability to respond efficiently to heat exposure in terms of both chromatin accessibility and gene expression and reinforces the importance of experimentally addressing ecological questions in the field.
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20
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Wice EW, Saltz JB. Selection on heritable social network positions is context-dependent in Drosophila melanogaster. Nat Commun 2021; 12:3357. [PMID: 34099680 PMCID: PMC8185000 DOI: 10.1038/s41467-021-23672-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 04/26/2021] [Indexed: 02/05/2023] Open
Abstract
Social group structure is highly variable and can be important for nearly every aspect of behavior and its fitness consequences. Group structure can be modeled using social network analysis, but we know little about the evolutionary factors shaping and maintaining variation in how individuals are embedded within their networks (i.e., network position). While network position is a pervasive target of selection, it remains unclear whether network position is heritable and can respond to selection. Furthermore, it is unclear how environmental factors interact with genotypic effects on network positions, or how environmental factors shape selection on heritable network structure. Here we show multiple measures of social network position are heritable, using replicate genotypes and replicate social groups of Drosophila melanogaster flies. Our results indicate genotypic differences in network position are largely robust to changes in the environment flies experience, though some measures of network position do vary across environments. We also show selection on multiple network position metrics depends on the environmental context they are expressed in, laying the groundwork for better understanding how spatio-temporal variation in selection contributes to the evolution of variable social group structure.
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21
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Ruf F, Mitesser O, Mungwa ST, Horn M, Rieger D, Hovestadt T, Wegener C. Natural Zeitgebers Under Temperate Conditions Cannot Compensate for the Loss of a Functional Circadian Clock in Timing of a Vital Behavior in Drosophila. J Biol Rhythms 2021; 36:271-285. [PMID: 33745356 PMCID: PMC8114442 DOI: 10.1177/0748730421998112] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The adaptive significance of adjusting behavioral activities to the right time of the day seems obvious. Laboratory studies implicated an important role of circadian clocks in behavioral timing and rhythmicity. Yet, recent studies on clock-mutant animals questioned this importance under more naturalistic settings, as various clock mutants showed nearly normal diel activity rhythms under seminatural zeitgeber conditions. We here report evidence that proper timing of eclosion, a vital behavior of the fruit fly Drosophila melanogaster, requires a functional molecular clock under quasi-natural conditions. In contrast to wild-type flies, period01 mutants with a defective molecular clock showed impaired rhythmicity and gating in a temperate environment even in the presence of a full complement of abiotic zeitgebers. Although period01 mutants still eclosed during a certain time window during the day, this time window was much broader and loosely defined, and rhythmicity was lower or lost as classified by various statistical measures. Moreover, peak eclosion time became more susceptible to variable day-to-day changes of light. In contrast, flies with impaired peptidergic interclock signaling (Pdf01 and han5304 PDF receptor mutants) eclosed mostly rhythmically with normal gate sizes, similar to wild-type controls. Our results suggest that the presence of natural zeitgebers is not sufficient, and a functional molecular clock is required to induce stable temporal eclosion patterns in flies under temperate conditions with considerable day-to-day variation in light intensity and temperature. Temperate zeitgebers are, however, sufficient to functionally rescue a loss of PDF-mediated clock-internal and -output signaling.
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Affiliation(s)
- Franziska Ruf
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Oliver Mitesser
- Animal Ecology and Tropical Biology, Theoretical Evolutionary Ecology Group, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Simon Tii Mungwa
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Melanie Horn
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Dirk Rieger
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Thomas Hovestadt
- Animal Ecology and Tropical Biology, Theoretical Evolutionary Ecology Group, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Christian Wegener
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Würzburg, Germany
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22
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Monteiro F, Rodrigues P, Nascimento CS, Simões F, Miguel M. The daily rhythms of working memory and their methodological constraints: a critical overview. BIOL RHYTHM RES 2021. [DOI: 10.1080/09291016.2021.1907511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Fábio Monteiro
- Department of Psychology and Education, University of Beira Interior, Covilhã, Portugal
| | - Paulo Rodrigues
- Department of Psychology and Education, University of Beira Interior, Covilhã, Portugal
| | | | - Fátima Simões
- Department of Psychology and Education, University of Beira Interior, Covilhã, Portugal
- Research Center in Education and Psychology of the University of Évora, University of Évora, Évora, Portugal
| | - Mário Miguel
- Department of Physiology and Behavior, Federal University of Rio Grande do Norte, Natal, Brazil
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23
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Teles-de-Freitas R, Rivas GBS, Peixoto AA, Bruno RV. The Summer Is Coming: nocte and timeless Genes Are Influenced by Temperature Cycles and May Affect Aedes aegypti Locomotor Activity. Front Physiol 2020; 11:614722. [PMID: 33424639 PMCID: PMC7786104 DOI: 10.3389/fphys.2020.614722] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/23/2020] [Indexed: 11/13/2022] Open
Abstract
Mosquitoes exhibit activity rhythms, crucial for the transmission of pathogens, under the control of a circadian clock. Aedes aegypti is one of the world’s leading vectors. For decades, several studies have linked the rise in ambient temperature with the increase in their activity. Here, we identify candidate genes whose expression is influenced by temperature cycles and may affect Aedes locomotor activity. We observed that timeless completely lost its rhythmic expression in light/dark, with out-of-phase temperature cycles, and by RNAi mediated knockdown of nocte, an important gene for Drosophila circadian synchronization by temperature cycles. Thus, timeless and nocte are important genes for synchronization by temperature cycles in Aedes aegypti. To reinforce our findings, we simulated in the laboratory the gradual temperature fluctuations that were as close as possible to daily temperature variations in Brazil. We observed that the activity and the expression of the molecular circadian clock of Ae. aegypti differs significantly from that of mosquitoes subjected to constant or rectangular abrupt changes in temperature. We suggest that for understanding the circadian behavior of Aedes with possible implications for intervention strategies, the seminatural paradigm needs to replace the traditional laboratory study.
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Affiliation(s)
- Rayane Teles-de-Freitas
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Gustavo B S Rivas
- Department of Biology, Center for Biological Clocks Research, Texas A&M University, College Station, TX, United States
| | - Alexandre A Peixoto
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM)/CNPq, Rio de Janeiro, Brazil
| | - Rafaela Vieira Bruno
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM)/CNPq, Rio de Janeiro, Brazil
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24
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Schäbler S, Amatobi KM, Horn M, Rieger D, Helfrich-Förster C, Mueller MJ, Wegener C, Fekete A. Loss of function in the Drosophila clock gene period results in altered intermediary lipid metabolism and increased susceptibility to starvation. Cell Mol Life Sci 2020; 77:4939-4956. [PMID: 31960114 PMCID: PMC7658074 DOI: 10.1007/s00018-019-03441-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 11/27/2019] [Accepted: 12/23/2019] [Indexed: 12/14/2022]
Abstract
The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period01 (per01) clock mutants and Canton-S wildtype (WTCS) flies in an isogenic and non-isogenic background using LC-MS. In the non-isogenic background, metabolites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per01 mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WTCS in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per01 mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per01 did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per01 mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants.
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Affiliation(s)
- Stefan Schäbler
- Pharmaceutical Biology, Julius-Von-Sachs-Institute, Biocenter, University of Würzburg, Julius-von-Sachs Platz 2, 97084, Würzburg, Germany
| | - Kelechi M Amatobi
- Pharmaceutical Biology, Julius-Von-Sachs-Institute, Biocenter, University of Würzburg, Julius-von-Sachs Platz 2, 97084, Würzburg, Germany
| | - Melanie Horn
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Dirk Rieger
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Martin J Mueller
- Pharmaceutical Biology, Julius-Von-Sachs-Institute, Biocenter, University of Würzburg, Julius-von-Sachs Platz 2, 97084, Würzburg, Germany
| | - Christian Wegener
- Neurobiology and Genetics, Würzburg Insect Research, Theodor-Boveri-Institute, Biocenter, University of Würzburg, Am Hubland, 97074, Würzburg, Germany.
| | - Agnes Fekete
- Pharmaceutical Biology, Julius-Von-Sachs-Institute, Biocenter, University of Würzburg, Julius-von-Sachs Platz 2, 97084, Würzburg, Germany.
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25
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Ueno T, Takahashi Y. Intrapopulation genetic variation in the level and rhythm of daily activity in Drosophila immigrans. Ecol Evol 2020; 10:14388-14393. [PMID: 33391722 PMCID: PMC7771174 DOI: 10.1002/ece3.7041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/07/2020] [Accepted: 10/30/2020] [Indexed: 01/12/2023] Open
Abstract
Genetic diversity within a population, such as polymorphisms and personality, is considered to improve population performance because such intraspecific variations have the potential to alleviate the competition for a limited resource or the risk of predation and sexual harassment at a population level. Variation in the level and rhythm of daily activity in a population could also affect population performance by directly altering ecological, social, and sexual interactions among individuals. However, it remains to be elucidated whether such intra-population variation in the level and rhythms of daily activity exists in a natural population. Here, we investigated the genetic variation in daily activity within a single natural population of Drosophila immigrans. We established 21 isofemale lines from a single natural population and measured larval activity level and the level and daily pattern of adult activity over a 24 hr period. Larval activity level significantly varied among isofemale lines. Likewise, the activity level in the adult stage significantly varied among lines. The significant variation was also found in the daily pattern of adult activity; some lines showed greater activity level in the daytime, and others showed greater activity level in the night. Our results consistently suggest that there is a genetic variation in behavioral activity in a natural population, probably contributing to shaping the population performance.
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Affiliation(s)
- Takahisa Ueno
- Graduate School of Science and EngineeringChiba UniversityChibaJapan
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26
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Beer K, Helfrich-Förster C. Model and Non-model Insects in Chronobiology. Front Behav Neurosci 2020; 14:601676. [PMID: 33328925 PMCID: PMC7732648 DOI: 10.3389/fnbeh.2020.601676] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/30/2020] [Indexed: 12/20/2022] Open
Abstract
The fruit fly Drosophila melanogaster is an established model organism in chronobiology, because genetic manipulation and breeding in the laboratory are easy. The circadian clock neuroanatomy in D. melanogaster is one of the best-known clock networks in insects and basic circadian behavior has been characterized in detail in this insect. Another model in chronobiology is the honey bee Apis mellifera, of which diurnal foraging behavior has been described already in the early twentieth century. A. mellifera hallmarks the research on the interplay between the clock and sociality and complex behaviors like sun compass navigation and time-place-learning. Nevertheless, there are aspects of clock structure and function, like for example the role of the clock in photoperiodism and diapause, which can be only insufficiently investigated in these two models. Unlike high-latitude flies such as Chymomyza costata or D. ezoana, cosmopolitan D. melanogaster flies do not display a photoperiodic diapause. Similarly, A. mellifera bees do not go into "real" diapause, but most solitary bee species exhibit an obligatory diapause. Furthermore, sociality evolved in different Hymenoptera independently, wherefore it might be misleading to study the social clock only in one social insect. Consequently, additional research on non-model insects is required to understand the circadian clock in Diptera and Hymenoptera. In this review, we introduce the two chronobiology model insects D. melanogaster and A. mellifera, compare them with other insects and show their advantages and limitations as general models for insect circadian clocks.
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Affiliation(s)
- Katharina Beer
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocentre, Am Hubland, University of Würzburg, Würzburg, Germany
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27
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The Effect of General Anaesthesia on Circadian Rhythms in Behaviour and Clock Gene Expression of Drosophila melanogaster. Clocks Sleep 2020; 2:434-441. [PMID: 33113932 PMCID: PMC7712384 DOI: 10.3390/clockssleep2040032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/09/2020] [Accepted: 10/22/2020] [Indexed: 11/16/2022] Open
Abstract
General anaesthesia (GA) is implicated as a cause of postoperative sleep disruption and fatigue with part of the disturbance being attributed to a shift of the circadian clock. In this study, Drosophila melanogaster was used as a model to determine how Isoflurane affects the circadian clock at the behavioural and molecular levels. We measured the response of the clock at both of these levels caused by different durations and different concentrations of Isoflurane at circadian time 4 (CT4). Once characterized, we held the duration and concentration constants (at 2% in air for 6 h) and calculated the phase responses over the entire circadian cycle in both activity and period expression. Phase advances in behaviour were observed during the subjective day, whereas phase delays were associated with subjective night time GA interventions. The corresponding pattern of gene expression preceded the behavioural pattern by approximately four hours. We discuss the implications of this effect for clinical and research practice.
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28
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Piccolin F, Pitzschler L, Biscontin A, Kawaguchi S, Meyer B. Circadian regulation of diel vertical migration (DVM) and metabolism in Antarctic krill Euphausia superba. Sci Rep 2020; 10:16796. [PMID: 33033314 PMCID: PMC7546626 DOI: 10.1038/s41598-020-73823-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 09/21/2020] [Indexed: 11/09/2022] Open
Abstract
Antarctic krill (Euphausia superba) are high latitude pelagic organisms which play a key ecological role in the ecosystem of the Southern Ocean. To synchronize their daily and seasonal life-traits with their highly rhythmic environment, krill rely on the implementation of rhythmic strategies which might be regulated by a circadian clock. A recent analysis of krill circadian transcriptome revealed that their clock might be characterized by an endogenous free-running period of about 12-15 h. Using krill exposed to simulated light/dark cycles (LD) and constant darkness (DD), we investigated the circadian regulation of krill diel vertical migration (DVM) and oxygen consumption, together with daily patterns of clock gene expression in brain and eyestalk tissue. In LD, we found clear 24 h rhythms of DVM and oxygen consumption, suggesting a synchronization with photoperiod. In DD, the DVM rhythm shifted to a 12 h period, while the peak of oxygen consumption displayed a temporal advance during the subjective light phase. This suggested that in free-running conditions the periodicity of these clock-regulated output functions might reflect the shortening of the endogenous period observed at the transcriptional level. Moreover, differences in the expression patterns of clock gene in brain and eyestalk, in LD and DD, suggested the presence in krill of a multiple oscillator system. Evidence of short periodicities in krill behavior and physiology further supports the hypothesis that a short endogenous period might represent a circadian adaption to cope with extreme seasonal photoperiodic variability at high latitude.
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Affiliation(s)
- Fabio Piccolin
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Section Polar Biological Oceanography, Am Handelshafen 12, 27570, Bremerhaven, Germany.
| | - Lisa Pitzschler
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Section Polar Biological Oceanography, Am Handelshafen 12, 27570, Bremerhaven, Germany
| | - Alberto Biscontin
- Department of Biology, University of Padova, Via Ugo Bassi 58/b, 35121, Padova, Italy
| | - So Kawaguchi
- Australian Antarctic Division, Department of the Environment and Energy, 203 Channel Hwy, Kingston, TAS, 7050, Australia
| | - Bettina Meyer
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Section Polar Biological Oceanography, Am Handelshafen 12, 27570, Bremerhaven, Germany. .,Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Carl-von-Ossietzky-Strasse 9-11, 26111, Oldenburg, Germany. .,Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg, Ammerländer Heerstrasse 231, 26129, Oldenburg, Germany.
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29
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Verly T, Costa S, Lima N, Mallet J, Odêncio F, Pereira M, Moreira CJDC, Britto C, Pavan MG. Vector competence and feeding-excretion behavior of Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) infected with Trypanosoma cruzi TcVI. PLoS Negl Trop Dis 2020; 14:e0008712. [PMID: 32970687 PMCID: PMC7544132 DOI: 10.1371/journal.pntd.0008712] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 10/08/2020] [Accepted: 08/13/2020] [Indexed: 01/22/2023] Open
Abstract
Background Several studies addressed changes on the insect vector behavior due to parasite infection, but little is known for triatomine bugs, vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. We assessed infection rates and metacyclogenesis of T. cruzi (TcVI) in fifth-instar nymphs of Triatoma rubrovaria comparing with the primary vector Triatoma infestans. Also, biological parameters related to feeding-excretion behavior were evaluated aiming to identify which variables are most influenced by T. cruzi infection. Methodology/principal findings Fifth-instar nymphs of T. rubrovaria and T. infestans were fed on mice infected with T. cruzi (TcVI). We compared the presence and the number of parasite evolutive forms in excreta of both triatomine species at 30, 60 and 90 days post-infection (dpi) with traditional statistical analyses. Moreover, both species were analyzed through generalized linear models and multinomial logistic regression hypotheses for seven behavioral parameters related to host-seeking and feeding-excretion. Triatoma rubrovaria and T. infestans had similar overall infection and metacyclogenesis rates of T. cruzi TcVI in laboratory conditions. Regarding vector behavior, we confirmed that the triatomine’s tendency is to move away from the bite region after a blood meal, probably to avoid being noticed by the vertebrate host. Interspecific differences were observed on the volume of blood ingested and on the proportion of individuals that excreted after the blood meal, revealing the higher feeding efficiency and dejection rates of T. infestans. The amount of ingested blood and the bite behavior of T. rubrovaria seems to be influenced by TcVI infection. Infected specimens tended to ingest ~25% more blood and to bite more the head of the host. Noteworthy, in two occasions, kleptohematophagy and coprophagy behaviors were also observed in T. rubrovaria. Conclusions/significance Laboratory infections revealed similar rate of T. cruzi TcVI trypomatigotes in excreta of T. rubrovaria and T. infestans, one of the most epidemiological important vectors of T. cruzi. Therefore, TcVI DTU was able to complete its life cycle in T. rubrovaria under laboratory conditions, and this infection changed the feeding behavior of T. rubrovaria. Considering these results, T. rubrovaria must be kept under constant entomological surveillance in Rio Grande do Sul, Brazil. Chagas disease is caused by the etiological agent Trypanosoma cruzi and is mainly transmitted through the excreta of triatomine vectors. It is endemic in Latin America and the Caribbean, affecting ~8 million people. Control programs are based on the elimination of domestic vectors through insecticide-spraying indoors, since there is no vaccine or efficient treatment for chronic patients. However, this strategy is not sustainable where native triatomine species are capable of colonizing peridomestic structures and reinvading human dwellings. Since the ‘virtual’ elimination of Triatomainfestans in Brazil (residual foci remain in Rio Grande do Sul and Bahia), specimens of the native Triatoma rubrovaria have been constantly collected inside human dwellings and peridomiciliary ecotopes in Rio Grande do Sul, southern Brazil, which might represent a real risk for human infections. Here we analyzed a unique and large dataset through classical and modern statistical methods to evaluate T. cruzi infection in T. rubrovaria and to identify host-seeking, and also feeding/excretion behavioral traits that could be influenced by the parasite. Our results indicated that the parasite infection caused changes in T. rubrovaria feeding behavior that could increase T. cruzi TcVI transmission. Moreover, this vector species had similar infection rate to one of the main important Chagas disease vectors in South America, T. infestans. Therefore, T. rubrovaria must be kept under constant entomological surveillance in Rio Grande do Sul, Brazil.
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Affiliation(s)
- Thaiane Verly
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | - Stephanie Costa
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | - Nathanielly Lima
- Laboratório Interdisciplinar de Vigilância Entomológica em Diptera e Hemiptera, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | - Jacenir Mallet
- Laboratório Interdisciplinar de Vigilância Entomológica em Diptera e Hemiptera, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
- Universidade Iguaçu - UNIG, Rio de Janeiro, Brazil
| | - Francisco Odêncio
- Laboratório de Ultraestrutura Celular, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | - Mirian Pereira
- Laboratório de Ultraestrutura Celular, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Constança Britto
- Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
| | - Márcio G. Pavan
- Laboratório de Mosquitos Transmissores de Hematozoários, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil
- * E-mail:
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30
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Mazzotta GM, Damulewicz M, Cusumano P. Better Sleep at Night: How Light Influences Sleep in Drosophila. Front Physiol 2020; 11:997. [PMID: 33013437 PMCID: PMC7498665 DOI: 10.3389/fphys.2020.00997] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/22/2020] [Indexed: 01/25/2023] Open
Abstract
Sleep-like states have been described in Drosophila and the mechanisms and factors that generate and define sleep-wake profiles in this model organism are being thoroughly investigated. Sleep is controlled by both circadian and homeostatic mechanisms, and environmental factors such as light, temperature, and social stimuli are fundamental in shaping and confining sleep episodes into the correct time of the day. Among environmental cues, light seems to have a prominent function in modulating the timing of sleep during the 24 h and, in this review, we will discuss the role of light inputs in modulating the distribution of the fly sleep-wake cycles. This phenomenon is of growing interest in the modern society, where artificial light exposure during the night is a common trait, opening the possibility to study Drosophila as a model organism for investigating shift-work disorders.
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Affiliation(s)
| | - Milena Damulewicz
- Department of Cell Biology and Imaging, Jagiellonian University, Kraków, Poland
| | - Paola Cusumano
- Department of Biology, University of Padova, Padua, Italy
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31
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Krittika S, Yadav P. Dietary protein restriction deciphers new relationships between lifespan, fecundity and activity levels in fruit flies Drosophila melanogaster. Sci Rep 2020; 10:10019. [PMID: 32572062 PMCID: PMC7308371 DOI: 10.1038/s41598-020-66372-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 05/07/2020] [Indexed: 11/10/2022] Open
Abstract
Drosophila melanogaster has been used in Diet Restriction (DR) studies for a few decades now, due to easy diet implementation and its short lifespan. Since the concentration of protein determines the trade-offs between lifespan and fecundity, it is important to understand the level of protein and the extent of its influence on lifespan, fecundity and activity of fruit flies. In this study, we intend to assess the effect of a series of protein restricted diets from age 1 day of the adult fly on these traits to understand the possible variations in trade-off across tested diets. We found that lifespan under different protein concentrations remains unaltered, even though protein restricted diets exerted an age-specific influence on fecundity. Interestingly, there was no difference in lifetime activity of the flies in most of the tested protein restricted (PR) diets, even though a sex-dependent influence of protein concentrations was observed. Additionally, we report that not all concentrations of PR diet increase activity, thereby suggesting that the correlation between lifespan and the lifetime activity can be challenged under protein-restricted condition. Therefore, the PR does not need to exert its effect on lifespan and fecundity only but can also influence activity levels of the flies, thereby emphasizing the role of nutrient allotment between lifespan, fecundity and activity.
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Affiliation(s)
- Sudhakar Krittika
- Fly Laboratory # 210, Anusandhan Kendra-II, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, 613401, Tamil Nadu, India
| | - Pankaj Yadav
- Fly Laboratory # 210, Anusandhan Kendra-II, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, 613401, Tamil Nadu, India.
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32
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Breda C, Rosato E, Kyriacou CP. Norpa Signalling and the Seasonal Circadian Locomotor Phenotype in Drosophila. BIOLOGY 2020; 9:biology9060130. [PMID: 32560221 PMCID: PMC7345481 DOI: 10.3390/biology9060130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/04/2020] [Accepted: 06/09/2020] [Indexed: 01/22/2023]
Abstract
In this paper, we review the role of the norpA-encoded phospholipase C in light and thermal entrainment of the circadian clock in Drosophila melanogaster. We extend our discussion to the role of norpA in the thermo-sensitive splicing of the per 3′ UTR, which has significant implications for seasonal adaptations of circadian behaviour. We use the norpA mutant-generated enhancement of per splicing and the corresponding advance that it produces in the morning (M) and evening (E) locomotor component to dissect out the neurons that are contributing to this norpA phenotype using GAL4/UAS. We initially confirmed, by immunocytochemistry and in situ hybridisation in adult brains, that norpA expression is mostly concentrated in the eyes, but we were unable to unequivocally reveal norpA expression in the canonical clock cells using these methods. In larval brains, we did see some evidence for co-expression of NORPA with PDF in clock neurons. Nevertheless, downregulation of norpA in clock neurons did generate behavioural advances in adults, with the eyes playing a significant role in the norpA seasonal phenotype at high temperatures, whereas the more dorsally located CRYPTOCHROME-positive clock neurons are the likely candidates for generating the norpA behavioural effects in the cold. We further show that knockdown of the related plc21C encoded phospholipase in clock neurons does not alter per splicing nor generate any of the behavioural advances seen with norpA. Our results with downregulating norpA and plc21C implicate the rhodopsins Rh2/Rh3/Rh4 in the eyes as mediating per 3′ UTR splicing at higher temperatures and indicate that the CRY-positive LNds, also known as ‘evening’ cells are likely mediating the low-temperature seasonal effects on behaviour via altering per 3′UTR splicing.
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33
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Andreatta G, Tessmar-Raible K. The Still Dark Side of the Moon: Molecular Mechanisms of Lunar-Controlled Rhythms and Clocks. J Mol Biol 2020; 432:3525-3546. [PMID: 32198116 PMCID: PMC7322537 DOI: 10.1016/j.jmb.2020.03.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/18/2020] [Accepted: 03/09/2020] [Indexed: 12/22/2022]
Abstract
Starting with the beginning of the last century, a multitude of scientific studies has documented that the lunar cycle times behaviors and physiology in many organisms. It is plausible that even the first life forms adapted to the different rhythms controlled by the moon. Consistently, many marine species exhibit lunar rhythms, and also the number of documented "lunar-rhythmic" terrestrial species is increasing. Organisms follow diverse lunar geophysical/astronomical rhythms, which differ significantly in terms of period length: from hours (circalunidian and circatidal rhythms) to days (circasemilunar and circalunar cycles). Evidence for internal circatital and circalunar oscillators exists for a range of species based on past behavioral studies, but those species with well-documented behaviorally free-running lunar rhythms are not typically used for molecular studies. Thus, the underlying molecular mechanisms are largely obscure: the dark side of the moon. Here we review findings that start to connect molecular pathways with moon-controlled physiology and behaviors. The present data indicate connections between metabolic/endocrine pathways and moon-controlled rhythms, as well as interactions between circadian and circatidal/circalunar rhythms. Moreover, recent high-throughput analyses provide useful leads toward pathways, as well as molecular markers. However, for each interpretation, it is important to carefully consider the, partly substantially differing, conditions used in each experimental paradigm. In the future, it will be important to use lab experiments to delineate the specific mechanisms of the different solar- and lunar-controlled rhythms, but to also start integrating them together, as life has evolved equally long under rhythms of both sun and moon.
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Affiliation(s)
- Gabriele Andreatta
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria
| | - Kristin Tessmar-Raible
- Max Perutz Labs, University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria; Research Platform "Rhythms of Life", University of Vienna, Vienna BioCenter, Dr. Bohr-Gasse 9/4, A-1030 Vienna, Austria.
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34
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Melnattur K, Zhang B, Shaw PJ. Disrupting flight increases sleep and identifies a novel sleep-promoting pathway in Drosophila. SCIENCE ADVANCES 2020; 6:eaaz2166. [PMID: 32494708 PMCID: PMC7209998 DOI: 10.1126/sciadv.aaz2166] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 02/25/2020] [Indexed: 06/06/2023]
Abstract
Sleep is plastic and is influenced by ecological factors and environmental changes. The mechanisms underlying sleep plasticity are not well understood. We show that manipulations that impair flight in Drosophila increase sleep as a form of sleep plasticity. We disrupted flight by blocking the wing-expansion program, genetically disrupting flight, and by mechanical wing perturbations. We defined a new sleep regulatory circuit starting with specific wing sensory neurons, their target projection neurons in the ventral nerve cord, and the neurons they connect to in the central brain. In addition, we identified a critical neuropeptide (burs) and its receptor (rickets) that link wing expansion and sleep. Disrupting flight activates these sleep-promoting projection neurons, as indicated by increased cytosolic calcium levels, and stably increases the number of synapses in their axonal projections. These data reveal an unexpected role for flight in regulating sleep and provide new insight into how sensory processing controls sleep need.
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Affiliation(s)
- K. Melnattur
- Department of Neuroscience, Washington University School of Medicine, Campus Box 8108, 660 South Euclid Avenue, St. Louis, MO 63110, USA
| | - B. Zhang
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - P. J. Shaw
- Department of Neuroscience, Washington University School of Medicine, Campus Box 8108, 660 South Euclid Avenue, St. Louis, MO 63110, USA
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35
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Kaniewska MM, Vaněčková H, Doležel D, Kotwica-Rolinska J. Light and Temperature Synchronizes Locomotor Activity in the Linden Bug, Pyrrhocoris apterus. Front Physiol 2020; 11:242. [PMID: 32300305 PMCID: PMC7142227 DOI: 10.3389/fphys.2020.00242] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/02/2020] [Indexed: 02/06/2023] Open
Abstract
Circadian clocks are synchronized with the external environment by light and temperature. The effect of these cues on behavior is well-characterized in Drosophila, however, little is known about synchronization in non-model insect species. Therefore, we explored entrainment of locomotor activity by light and temperature in the linden bug Pyrrhocoris apterus (Heteroptera), an insect species with a strong seasonal response (reproductive diapause), which is triggered by both photoperiod and thermoperiod. Our results show that either light or temperature cycles are strong factors entraining P. apterus locomotor activity. Pyrrhocoris is able to be partially synchronized by cycles with temperature amplitude as small as 3°C and more than 50% of bugs is synchronized by 5°C steps. If conflicting zeitgebers are provided, light is the stronger signal. Linden bugs lack light-sensitive (Drosophila-like) cryptochrome. Notably, a high percentage of bugs is rhythmic even in constant light (LL) at intensity ∼400 lux, a condition which induces 100% arrhythmicity in Drosophila. However, the rhythmicity of bugs is still reduced in LL conditions, whereas rhythmicity remains unaffected in constant dark (DD). Interestingly, a similar phenomenon is observed after temperature cycles entrainment. Bugs released to constant thermophase and DD display weak rhythmicity, whereas strong rhythmicity is observed in bugs released to constant cryophase and DD. Our study describes the daily and circadian behavior of the linden bug as a response to photoperiodic and thermoperiodic entraining cues. Although the molecular mechanism of the circadian clock entrainment in the linden bug is virtually unknown, our study contributes to the knowledge of the insect circadian clock features beyond Drosophila research.
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Affiliation(s)
- Magdalena Maria Kaniewska
- Institute of Entomology, Biology Centre of Academy of Sciences of the Czech Republic, České Budějovice, Czechia.,Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Hana Vaněčková
- Institute of Entomology, Biology Centre of Academy of Sciences of the Czech Republic, České Budějovice, Czechia
| | - David Doležel
- Institute of Entomology, Biology Centre of Academy of Sciences of the Czech Republic, České Budějovice, Czechia.,Faculty of Science, University of South Bohemia, České Budějovice, Czechia
| | - Joanna Kotwica-Rolinska
- Institute of Entomology, Biology Centre of Academy of Sciences of the Czech Republic, České Budějovice, Czechia
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36
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Small eyes in dim light: Implications to spatio-temporal visual abilities in Drosophila melanogaster. Vision Res 2020; 169:33-40. [DOI: 10.1016/j.visres.2020.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/27/2020] [Accepted: 02/27/2020] [Indexed: 02/07/2023]
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37
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de Azevedo RVDM, Hansen C, Chen KF, Rosato E, Kyriacou CP. Disrupted Glutamate Signaling in Drosophila Generates Locomotor Rhythms in Constant Light. Front Physiol 2020; 11:145. [PMID: 32210832 PMCID: PMC7069353 DOI: 10.3389/fphys.2020.00145] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 02/11/2020] [Indexed: 01/23/2023] Open
Abstract
We have used the Cambridge Protein Trap resource (CPTI) to screen for flies whose locomotor rhythms are rhythmic in constant light (LL) as a means of identifying circadian photoreception genes. From the screen of ∼150 CPTI lines, we obtained seven hits, two of which targeted the glutamate pathway, Got1 (Glutamate oxaloacetate transaminase 1) and Gs2 (Glutamine synthetase 2). We focused on these by employing available mutants and observed that variants of these genes also showed high levels of LL rhythmicity compared with controls. It was also clear that the genetic background was important with a strong interaction observed with the common and naturally occurring timeless (tim) polymorphisms, ls-tim and s-tim. The less circadian photosensitive ls-tim allele generated high levels of LL rhythmicity in combination with Got1 or Gs2, even though ls-tim and s-tim alleles do not, by themselves, generate the LL phenotype. The use of dsRNAi for both genes as well as for Gad (Glutamic acid decarboxylase) and the metabotropic glutamate receptor DmGluRA driven by clock gene promoters also revealed high levels of LL rhythmicity compared to controls. It is clear that the glutamate pathway is heavily implicated in circadian photoreception. TIM levels in Got1 and Gs2 mutants cycled and were more abundant than in controls under LL. Got1 but not Gs2 mutants showed diminished phase shifts to 10 min light pulses. Neurogenetic dissection of the LL rhythmic phenotype using the gal4/gal80 UAS bipartite system suggested that the more dorsal CRY-negative clock neurons, DNs and LNds were responsible for the LL phenotype. Immunocytochemistry using the CPTI YFP tagged insertions for the two genes revealed that the DN1s but not the DN2 and DN3s expressed Got1 and Gs2, but expression was also observed in the lateral neurons, the LNds and s-LNvs. Expression of both genes was also found in neuroglia. However, downregulation of glial Gs2 and Got1 using repo-gal4 did not generate high levels of LL rhythmicity, so it is unlikely that this phenotype is mediated by glial expression. Our results suggest a model whereby the DN1s and possibly CRY-negative LNds use glutamate signaling to supress the pacemaker s-LNvs in LL.
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Affiliation(s)
| | - Celia Hansen
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Ko-Fan Chen
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Ezio Rosato
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Charalambos P Kyriacou
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
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Häfker NS, Tessmar-Raible K. Rhythms of behavior: are the times changin’? Curr Opin Neurobiol 2020; 60:55-66. [DOI: 10.1016/j.conb.2019.10.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/25/2019] [Accepted: 10/29/2019] [Indexed: 02/07/2023]
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Abhilash L, Ramakrishnan A, Priya S, Sheeba V. Waveform Plasticity under Entrainment to 12-h T-cycles in Drosophila melanogaster: Behavior, Neuronal Network, and Evolution. J Biol Rhythms 2020; 35:145-157. [PMID: 31994435 DOI: 10.1177/0748730419899549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A crucial property of circadian clocks is the ability to regulate the shape of an oscillation over its cycle length (waveform) appropriately, thus enhancing Darwinian fitness. Many studies over the past decade have revealed interesting ways in which the waveform of rodent behavior could be manipulated, one of which is that the activity bout bifurcates under environments that have 2 light/dark cycles within one 24-h day (LDLD). It has been observed that such unique, although unnatural, environments reveal acute changes in the circadian clock network. However, although adaptation of waveforms to different photoperiods is well studied, modulation of waveforms under LDLD has received relatively less attention in research on insect rhythms. Therefore, we undertook this study to ask the following questions: what is the extent of waveform plasticity that Drosophila melanogaster exhibits, and what are the neuronal underpinnings of such plasticity under LDLD? We found that the activity/rest rhythms of wild-type flies do not bifurcate under LDLD. Instead, they show similar but significantly different behavior from that under a long-day LD cycle. This behavior is accompanied by differences in the organization of the circadian neuronal network, which include changes in waveforms of a core clock component and an output molecule. In addition, to understand the functional significance of such variations in the waveform, we examined laboratory selected populations that exhibit divergent eclosion chronotypes (and therefore, waveforms). We found that populations selected for predominant eclosion in an evening window (late chronotypes) showed reduced amplitude plasticity and increased phase plasticity of activity/rest rhythms. This, we argue, is reflective of divergent evolution of circadian neuronal network organization in our laboratory selected flies.
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Affiliation(s)
- Lakshman Abhilash
- Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, Karnataka, India
| | - Aishwarya Ramakrishnan
- Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, Karnataka, India
| | - Srishti Priya
- Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, Karnataka, India
| | - Vasu Sheeba
- Behavioural Neurogenetics Laboratory, Neuroscience Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore, Karnataka, India
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40
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Ferreira CH, Moita MA. What can a non-eusocial insect tell us about the neural basis of group behaviour? CURRENT OPINION IN INSECT SCIENCE 2019; 36:118-124. [PMID: 31563022 DOI: 10.1016/j.cois.2019.09.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 08/25/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Group behaviour has been extensively studied in canonically social swarming, shoaling and flocking vertebrates and invertebrates, providing great insight into the behavioural and ecological aspects of group living. However, the search for its neuronal basis is lagging behind. In the natural environment, Drosophila melanogaster, increasingly used as a model to study neuronal circuits and behaviour, spend their lives surrounded by several conspecifics of different stages, as well as heterospecifics. Despite their dynamic multi-organism natural environment, the neuronal basis of social behaviours has been typically studied in dyadic interactions, such as mating or aggression. This review will focus on recent studies regarding how the behaviour of fruit flies can be shaped by the nature of the surrounding group. We argue that the rich social environment of Drosophila melanogaster, its arsenal of neurogenetic tools and the ability to use large sample sizes for detailed quantitative behavioural analysis makes this species ideal for mechanistic studies of group behaviour.
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Affiliation(s)
- Clara H Ferreira
- Champalimaud Research, Champalimaud Center for the Unknown, 1400-038 Lisbon, Portugal.
| | - Marta A Moita
- Champalimaud Research, Champalimaud Center for the Unknown, 1400-038 Lisbon, Portugal.
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41
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Tarrant AM, Helm RR, Levy O, Rivera HE. Environmental entrainment demonstrates natural circadian rhythmicity in the cnidarian Nematostella vectensis. ACTA ACUST UNITED AC 2019; 222:jeb.205393. [PMID: 31611292 DOI: 10.1242/jeb.205393] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 10/10/2019] [Indexed: 12/21/2022]
Abstract
Considerable advances in chronobiology have been made through controlled laboratory studies, but distinct temporal rhythms can emerge under natural environmental conditions. Lab-reared Nematostella vectensis sea anemones exhibit circadian behavioral and physiological rhythms. Given that these anemones inhabit shallow estuarine environments subject to tidal inputs, it was unclear whether circadian rhythmicity would persist following entrainment in natural conditions, or whether circatidal periodicity would predominate. Nematostella were conditioned within a marsh environment, where they experienced strong daily temperature cycles as well as brief tidal flooding around the full and new moons. Upon retrieval, anemones exhibited strong circadian (∼24 h) activity rhythms under a light-dark cycle or continuous darkness, but reduced circadian rhythmicity under continuous light. However, some individuals in each light condition showed circadian rhythmicity, and a few individuals showed circatidal rhythmicity. Consistent with the behavioral studies, a large number of transcripts (1640) exhibited diurnal rhythmicity compared with very few (64) with semidiurnal rhythmicity. Diurnal transcripts included core circadian regulators, and 101 of 434 (23%) genes that were previously found to be upregulated by exposure to ultraviolet radiation. Together, these behavioral and transcriptional studies show that circadian rhythmicity predominates and suggest that solar radiation drives physiological cycles in this sediment-dwelling subtidal animal.
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Affiliation(s)
- Ann M Tarrant
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA
| | - Rebecca R Helm
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA.,Biology Department, University of North Carolina Asheville, Asheville NC 28804, USA
| | - Oren Levy
- Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Hanny E Rivera
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA.,Biology Department, Boston University, Boston MA 02215, USA
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42
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Horn M, Mitesser O, Hovestadt T, Yoshii T, Rieger D, Helfrich-Förster C. The Circadian Clock Improves Fitness in the Fruit Fly, Drosophila melanogaster. Front Physiol 2019; 10:1374. [PMID: 31736790 PMCID: PMC6838225 DOI: 10.3389/fphys.2019.01374] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 10/17/2019] [Indexed: 12/17/2022] Open
Abstract
It is assumed that a properly timed circadian clock enhances fitness, but only few studies have truly demonstrated this in animals. We raised each of the three classical Drosophila period mutants for >50 generations in the laboratory in competition with wildtype flies. The populations were either kept under a conventional 24-h day or under cycles that matched the mutant’s natural cycle, i.e., a 19-h day in the case of pers mutants and a 29-h day for perl mutants. The arrhythmic per0 mutants were grown together with wildtype flies under constant light that renders wildtype flies similar arrhythmic as the mutants. In addition, the mutants had to compete with wildtype flies for two summers in two consecutive years under outdoor conditions. We found that wildtype flies quickly outcompeted the mutant flies under the 24-h laboratory day and under outdoor conditions, but perl mutants persisted and even outnumbered the wildtype flies under the 29-h day in the laboratory. In contrast, pers and per0 mutants did not win against wildtype flies under the 19-h day and constant light, respectively. Our results demonstrate that wildtype flies have a clear fitness advantage in terms of fertility and offspring survival over the period mutants and – as revealed for perl mutants – this advantage appears maximal when the endogenous period resonates with the period of the environment. However, the experiments indicate that perl and pers persist at low frequencies in the population even under the 24-h day. This may be a consequence of a certain mating preference of wildtype and heterozygous females for mutant males and time differences in activity patterns between wildtype and mutants.
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Affiliation(s)
- Melanie Horn
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, Julius-Maximilians University Würzburg, Würzburg, Germany
| | - Oliver Mitesser
- Theoretical Evolutionary Ecology Group, Biocenter, Department of Animal Ecology and Tropical Biology, Julius-Maximilians University Würzburg, Würzburg, Germany
| | - Thomas Hovestadt
- Theoretical Evolutionary Ecology Group, Biocenter, Department of Animal Ecology and Tropical Biology, Julius-Maximilians University Würzburg, Würzburg, Germany
| | - Taishi Yoshii
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Dirk Rieger
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, Julius-Maximilians University Würzburg, Würzburg, Germany
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, Julius-Maximilians University Würzburg, Würzburg, Germany
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43
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Bertolini E, Schubert FK, Zanini D, Sehadová H, Helfrich-Förster C, Menegazzi P. Life at High Latitudes Does Not Require Circadian Behavioral Rhythmicity under Constant Darkness. Curr Biol 2019; 29:3928-3936.e3. [PMID: 31679928 DOI: 10.1016/j.cub.2019.09.032] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 08/13/2019] [Accepted: 09/12/2019] [Indexed: 01/08/2023]
Abstract
Nearly all organisms evolved endogenous self-sustained timekeeping mechanisms to track and anticipate cyclic changes in the environment. Circadian clocks, with a periodicity of about 24 h, allow animals to adapt to day-night cycles. Biological clocks are highly adaptive, but strong behavioral rhythms might be a disadvantage for adaptation to weakly rhythmic environments such as polar areas [1, 2]. Several high-latitude species, including Drosophila species, were found to be highly arrhythmic under constant conditions [3-6]. Furthermore, Drosophila species from subarctic regions can extend evening activity until dusk under long days. These traits depend on the clock network neurochemistry, and we previously proposed that high-latitude Drosophila species evolved specific clock adaptations to colonize polar regions [5, 7, 8]. We broadened our analysis to 3 species of the Chymomyza genus, which diverged circa 5 million years before the Drosophila radiation [9] and colonized both low and high latitudes [10, 11]. C. costata, pararufithorax, and procnemis, independently of their latitude of origin, possess the clock neuronal network of low-latitude Drosophila species, and their locomotor activity does not track dusk under long photoperiods. Nevertheless, the high-latitude C. costata becomes arrhythmic under constant darkness (DD), whereas the two low-latitude species remain rhythmic. Different mechanisms are behind the arrhythmicity in DD of C. costata and the high-latitude Drosophila ezoana, suggesting that the ability to maintain behavioral rhythms has been lost more than once during drosophilids' evolution and that it might indeed be an evolutionary adaptation for life at high latitudes.
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Affiliation(s)
- Enrico Bertolini
- Neurobiology and Genetics, Theodor Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Frank K Schubert
- Neurobiology and Genetics, Theodor Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Damiano Zanini
- Neurobiology and Genetics, Theodor Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Hana Sehadová
- Faculty of Science, Biology Centre of the Czech Academy of Sciences, Institute of Entomology and University of South Bohemia, 37005 Ceske Budejovice, Czech Republic
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, Theodor Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany
| | - Pamela Menegazzi
- Neurobiology and Genetics, Theodor Boveri Institute, Biocentre, University of Würzburg, 97074 Würzburg, Germany.
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44
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Schlichting M, Weidner P, Diaz M, Menegazzi P, Dalla Benetta E, Helfrich-Förster C, Rosbash M. Light-Mediated Circuit Switching in the Drosophila Neuronal Clock Network. Curr Biol 2019; 29:3266-3276.e3. [PMID: 31564496 DOI: 10.1016/j.cub.2019.08.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/28/2019] [Accepted: 08/13/2019] [Indexed: 12/16/2022]
Abstract
The circadian clock is a timekeeper but also helps adapt physiology to the outside world. This is because an essential feature of clocks is their ability to adjust (entrain) to the environment, with light being the most important signal. Whereas cryptochrome-mediated entrainment is well understood in Drosophila, integration of light information via the visual system lacks a neuronal or molecular mechanism. Here, we show that a single photoreceptor subtype is essential for long-day adaptation. These cells activate key circadian neurons, namely the large ventral-lateral neurons (lLNvs), which release the neuropeptide pigment-dispersing factor (PDF). RNAi and rescue experiments show that PDF from these cells is necessary and sufficient for delaying the timing of the evening (E) activity in long-day conditions. This contrasts to PDF that derives from the small ventral-lateral neurons (sLNvs), which are essential for constant darkness (DD) rhythmicity. Using a cell-specific CRISPR/Cas9 assay, we show that lLNv-derived PDF directly interacts with neurons important for E activity timing. Interestingly, this pathway is specific for long-day adaptation and appears to be dispensable in equinox or DD conditions. The results therefore indicate that external cues cause a rearrangement of neuronal hierarchy, which contributes to behavioral plasticity.
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Affiliation(s)
- Matthias Schlichting
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02454, USA.
| | - Patrick Weidner
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02454, USA; Department for Neurobiology and Genetics, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Madelen Diaz
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02454, USA
| | - Pamela Menegazzi
- Department for Neurobiology and Genetics, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Elena Dalla Benetta
- Department for Neurobiology and Genetics, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | | | - Michael Rosbash
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02454, USA
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45
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Shaw B, Fountain M, Wijnen H. Control of Daily Locomotor Activity Patterns in Drosophila suzukii by the Circadian Clock, Light, Temperature and Social Interactions. J Biol Rhythms 2019; 34:463-481. [PMID: 31436123 DOI: 10.1177/0748730419869085] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Understanding behavioral rhythms in a pest species can contribute to improving the efficacy of control methods targeting that pest. However, in some species, the behavioral patterns recorded in artificial conditions contrast greatly with observed wild-type behavioral rhythms. In this study, we identify the determinants of daily activity rhythms of the soft and stone fruit pest Drosophila suzukii. The impact of gender, space, social housing, temperature, light, fly morph, and the circadian clock on D. suzukii locomotor rhythms was investigated. Assays were performed under artificial laboratory conditions or more natural semifield conditions to identify how these factors affected daily locomotor behavior. Daily locomotor activity patterns collected under semifield conditions varied very little between the various sex and social condition combinations. However, in lab-based assays, individual and group-housed males often exhibited divergent activity patterns, with more prominent hyperactivity at light/dark transitions. In contrast, hyperactivity responses were suppressed under lab protocols mimicking summer conditions for groups of females and mixed-sex groups. Moreover, when environmental cues were removed, flies held in groups displayed stronger rhythmicity than individual flies. Thus, social interactions can reinforce circadian behavior and resist hyperactivity responses in D. suzukii. Fly morph appeared to have little impact on behavioral pattern, with winter and summer morph flies displaying similar activity profiles under April semifield and laboratory mimic environmental conditions. In conclusion, separate and combined effects of light, temperature, circadian clock function, and social interactions were apparent in the daily activity profiles of D. suzukii. When groups of female or mixed-sex flies were used, implementation of matching photoperiods and realistic daily temperature gradients in the lab was sufficient to re-create behavioral patterns observed in summer semifield settings. The ability to leverage lab assays to predict D. suzukii field behavior promises to be a valuable asset in improving control measures for this pest.
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Affiliation(s)
- Bethan Shaw
- NIAB EMR, East Malling, Kent, UK.,School of Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, UK
| | | | - Herman Wijnen
- School of Biological Sciences and Institute for Life Sciences, University of Southampton, Southampton, UK
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46
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Hansen CN, Özkaya Ö, Roe H, Kyriacou CP, Giongo L, Rosato E. Locomotor Behaviour and Clock Neurons Organisation in the Agricultural Pest Drosophila suzukii. Front Physiol 2019; 10:941. [PMID: 31396106 PMCID: PMC6667661 DOI: 10.3389/fphys.2019.00941] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 07/09/2019] [Indexed: 01/29/2023] Open
Abstract
Drosophila suzukii (Matsumara) also called Spotted Wing Drosophila (SWD), is an invasive pest species originally from Asia that has now spread widely across Europe and North America. The majority of drosophilids including the best known Drosophila melanogaster only breed on decaying fruits. On the contrary, the presence of a strong serrated ovipositor and behavioural and metabolic adaptations allow D. suzukii to lay eggs inside healthy, ripening fruits that are still on the plant. Here we present an analysis of the rhythmic locomotor activity behaviour of D. suzukii under several laboratory settings. Moreover, we identify the canonical clock neurons in this species by reporting the expression pattern of the major clock proteins in the brain. Interestingly, a fundamentally similar organisation of the clock neurons network between D. melanogaster and D. suzukii does not correspond to similar characteristics in rhythmic locomotor activity behaviour.
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Affiliation(s)
- Celia Napier Hansen
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Özge Özkaya
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Helen Roe
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Charalambos P Kyriacou
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Lara Giongo
- Centro Ricerca e Innovazione, Fondazione Edmund Mach, Trento, Italy
| | - Ezio Rosato
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
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47
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Abstract
Fruit flies evolved in tropical regions under stable light-dark cycles. However, their photosensitive circadian clock had to adapt to extreme seasonal photoperiods during their colonisation of temperate regions. This was achieved by changing the neuronal expression of two key clock-related components.
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48
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Salmela MJ, Weinig C. The fitness benefits of genetic variation in circadian clock regulation. CURRENT OPINION IN PLANT BIOLOGY 2019; 49:86-93. [PMID: 31302588 DOI: 10.1016/j.pbi.2019.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 05/31/2019] [Accepted: 06/04/2019] [Indexed: 06/10/2023]
Abstract
Functional circadian clocks are essential for fitness in diverse ecosystems, facilitating detection of predictable light-dark and temperature cycles. The molecular basis of endogenous clocks is variable across the tree of life, but it has one omnipresent attribute: natural genetic diversity that manifests as variation for instance in circadian period length around the hypothesised optimum of 24 hours. Latitudinal variation in photoperiod alone is unlikely to account for the vast diversity documented in varied organisms, but we have yet to achieve a solid understanding of the interplay between clock variability and natural selection. Recent circadian studies sampling populations have drawn attention to the hierarchical structure of genetic diversity in the wild, unveiling pronounced genetic variation even on a scale of metres.
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Affiliation(s)
- Matti J Salmela
- Natural Resources Institute Finland, Latokartanonkaari 9, 00790 Helsinki, Finland
| | - Cynthia Weinig
- Department of Botany, 3165, University of Wyoming, 1000 E. University Ave., Laramie, WY 82071, USA; Program in Ecology, University of Wyoming, Laramie, WY 82071, USA; Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA.
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49
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Baik LS, Recinos Y, Chevez JA, Au DD, Holmes TC. Multiple Phototransduction Inputs Integrate to Mediate UV Light-evoked Avoidance/Attraction Behavior in Drosophila. J Biol Rhythms 2019; 34:391-400. [PMID: 31140349 DOI: 10.1177/0748730419847339] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Short-wavelength light guides many behaviors that are crucial for an insect's survival. In Drosophila melanogaster, short-wavelength light induces both attraction and avoidance behaviors. How light cues evoke two opposite valences of behavioral responses remains unclear. Here, we comprehensively examine the effects of (1) light intensity, (2) timing of light (duration of exposure, circadian time of day), and (3) phototransduction mechanisms processing light information that determine avoidance versus attraction behavior assayed at high spatiotemporal resolution in Drosophila. External opsin-based photoreceptors signal for attraction behavior in response to low-intensity ultraviolet (UV) light. In contrast, the cell-autonomous neuronal photoreceptors, CRYPTOCHROME (CRY) and RHODOPSIN 7 (RH7), signal avoidance responses to high-intensity UV light. In addition to binary attraction versus avoidance behavioral responses to UV light, flies show distinct clock-dependent spatial preference within a light environment coded by different light input channels.
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Affiliation(s)
- Lisa Soyeon Baik
- Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California
| | - Yocelyn Recinos
- Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California
| | - Joshua A Chevez
- Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California
| | - David D Au
- Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California
| | - Todd C Holmes
- Department of Physiology and Biophysics, School of Medicine, University of California at Irvine, Irvine, California
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Srivastava M, Varma V, Abhilash L, Sharma VK, Sheeba V. Circadian Clock Properties and Their Relationships as a Function of Free-Running Period in Drosophila melanogaster. J Biol Rhythms 2019; 34:231-248. [PMID: 30939971 DOI: 10.1177/0748730419837767] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The stability of circadian clock mechanisms under cyclic environments contributes to increased Darwinian fitness by accurately timing daily behavior and physiology. Earlier studies on biological clocks speculated that the timing of behavior and its accuracy are determined by the intrinsic period (τ) of the circadian clock under constant conditions, its stability, the period of the external cycle (T), and resetting of the clock by environmental time cues. However, most of these previous studies suffered from certain limitations, the major ones being a narrow range of examined τ values and a non-uniformity in the genetic background across the individuals tested. We present data that rigorously test the following hypotheses by employing Drosophila melanogaster fruit flies with τ ranging from 17 to 30 h in a uniform genetic background. We tested whether 1) precision (day-to-day stability of τ) is greater for clocks with τ close to 24 h; 2) accuracy (i.e., day-to-day stability of the phase relationship (ψ), where ψ is the duration between a phase of the rhythm and a phase of the external cycle) is greater for clocks with τ close to 24 h; 3) Ψ is delayed with an increase in τ; and 4) Ψ becomes more advanced with an increase in length of zeitgeber cycle (T). We show that precision is not always maximum for ~24-h clocks, but that accuracy is greatest when τ approximates T. Further, flies exhibit a delayed phase relationship with increasing τ and an advanced phase relationship under long T-cycles as compared with shorter T-cycles. We also describe relationships between activity and rest durations and how our observations fit predictions from models of circadian entrainment. Overall, we confirm that accuracy and phase of entrained rhythm are governed by both intrinsic clock period and the length of the external cycle; however, we find that the relationship between intrinsic period and precision does not fit previous predictions.
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Affiliation(s)
- Manishi Srivastava
- Chronobiology Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka India
| | - Vishwanath Varma
- Chronobiology Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka India
| | - Lakshman Abhilash
- Chronobiology Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka India
| | - Vijay Kumar Sharma
- Chronobiology Laboratory, Evolutionary and Integrative Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka India
| | - Vasu Sheeba
- Behavioural Neurogenetics Laboratory, Neurosciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka India
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