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Lymer S, Patel K, Lennon J, Blau J. Circadian clock neurons use activity-regulated gene expression for structural plasticity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.25.595887. [PMID: 38826237 PMCID: PMC11142243 DOI: 10.1101/2024.05.25.595887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Drosophila s-LNv circadian pacemaker neurons show dramatic structural plasticity, with their projections expanded at dawn and then retracted by dusk. This predictable plasticity makes s-LNvs ideal to study molecular mechanisms of plasticity. Although s-LNv plasticity is controlled by their molecular clock, changing s-LNv excitability also regulates plasticity. Here, we tested the idea that s-LNvs use activity-regulated genes to control plasticity. We found that inducing expression of either of the activity-regulated transcription factors Hr38 or Sr (orthologs of mammalian Nr4a1 and Egr1) is sufficient to rapidly expand s-LNv projections. Conversely, transiently knocking down expression of either Hr38 or sr blocks expansion of s-LNv projections at dawn. We show that Hr38 rapidly induces transcription of sif, which encodes a Rac1 GEF required for s-LNv plasticity rhythms. We conclude that the s-LNv molecular clock controls s-LNv excitability, which couples to an activity-regulated gene expression program to control s-LNv plasticity.
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Ehrlich A, Xu AA, Luminari S, Kidd S, Treiber CD, Russo J, Blau J. Tango-seq: overlaying transcriptomics on connectomics to identify neurons downstream of Drosophila clock neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.22.595372. [PMID: 38826334 PMCID: PMC11142192 DOI: 10.1101/2024.05.22.595372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Knowing how neural circuits change with neuronal plasticity and differ between individuals is important to fully understand behavior. Connectomes are typically assembled using electron microscopy, but this is low throughput and impractical for analyzing plasticity or mutations. Here, we modified the trans-Tango genetic circuit-tracing technique to identify neurons synaptically downstream of Drosophila s-LNv clock neurons, which show 24hr plasticity rhythms. s-LNv target neurons were labeled specifically in adult flies using a nuclear reporter gene, which facilitated their purification and then single cell sequencing. We call this Tango-seq, and it allows transcriptomic data - and thus cell identity - to be overlayed on top of anatomical data. We found that s-LNvs preferentially make synaptic connections with a subset of the CNMa+ DN1p clock neurons, and that these are likely plastic connections. We also identified synaptic connections between s-LNvs and mushroom body Kenyon cells. Tango-seq should be a useful addition to the connectomics toolkit.
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Affiliation(s)
- Alison Ehrlich
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Angelina A Xu
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Sofia Luminari
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Simon Kidd
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Christoph D Treiber
- Centre for Neural Circuits and Behaviour, University of Oxford, UK
- Current address: Department of Biology, University of Oxford, UK
| | - Jordan Russo
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Justin Blau
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
- Center for Genomics and Systems Biology (CGSB), New York University Abu Dhabi, Abu Dhabi, UAE
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3
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Hofbauer B, Zandawala M, Reinhard N, Rieger D, Werner C, Evers JF, Wegener C. The neuropeptide pigment-dispersing factor signals independently of Bruchpilot-labelled active zones in daily remodelled terminals of Drosophila clock neurons. Eur J Neurosci 2024; 59:2665-2685. [PMID: 38414155 DOI: 10.1111/ejn.16294] [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: 06/21/2023] [Revised: 02/06/2024] [Accepted: 02/08/2024] [Indexed: 02/29/2024]
Abstract
The small ventrolateral neurons (sLNvs) are key components of the central clock in the Drosophila brain. They signal via the neuropeptide pigment-dispersing factor (PDF) to align the molecular clockwork of different central clock neurons and to modulate downstream circuits. The dorsal terminals of the sLNvs undergo daily morphological changes that affect presynaptic sites organised by the active zone protein Bruchpilot (BRP), a homolog of mammalian ELKS proteins. However, the role of these presynaptic sites for PDF release is ill-defined. Here, we combined expansion microscopy with labelling of active zones by endogenously tagged BRP to examine the spatial correlation between PDF-containing dense-core vesicles and BRP-labelled active zones. We found that the number of BRP-labelled puncta in the sLNv terminals was similar while their density differed between Zeitgeber time (ZT) 2 and 14. The relative distance between BRP- and PDF-labelled puncta was increased in the morning, around the reported time of PDF release. Spontaneous dense-core vesicle release profiles of sLNvs in a publicly available ssTEM dataset (FAFB) consistently lacked spatial correlation to BRP-organised active zones. RNAi-mediated downregulation of brp and other active zone proteins expressed by the sLNvs did not affect PDF-dependent locomotor rhythmicity. In contrast, down-regulation of genes encoding proteins of the canonical vesicle release machinery, the dense-core vesicle-related protein CADPS, as well as PDF impaired locomotor rhythmicity. Taken together, our study suggests that PDF release from the sLNvs is independent of BRP-organised active zones, while BRP may be redistributed to active zones in a time-dependent manner.
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Affiliation(s)
- Benedikt Hofbauer
- Biocenter, Theodor-Boveri-Institute, Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Meet Zandawala
- Biocenter, Theodor-Boveri-Institute, Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
- Department of Biochemistry and Molecular Biology, University of Nevada Reno, Reno, NV, USA
| | - Nils Reinhard
- Biocenter, Theodor-Boveri-Institute, Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Dirk Rieger
- Biocenter, Theodor-Boveri-Institute, Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Christian Werner
- Biocenter, Theodor-Boveri-Institute, Department of Biotechnology and Biophysics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Jan Felix Evers
- Centre for organismal studies COS, Universität Heidelberg, Heidelberg, Germany
- Cairn GmbH, Heidelberg, Germany
| | - Christian Wegener
- Biocenter, Theodor-Boveri-Institute, Neurobiology and Genetics, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
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Mariano V, Kanellopoulos AK, Ricci C, Di Marino D, Borrie SC, Dupraz S, Bradke F, Achsel T, Legius E, Odent S, Billuart P, Bienvenu T, Bagni C. Intellectual Disability and Behavioral Deficits Linked to CYFIP1 Missense Variants Disrupting Actin Polymerization. Biol Psychiatry 2024; 95:161-174. [PMID: 37704042 DOI: 10.1016/j.biopsych.2023.08.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/27/2023] [Accepted: 08/31/2023] [Indexed: 09/15/2023]
Abstract
BACKGROUND 15q11.2 deletions and duplications have been linked to autism spectrum disorder, schizophrenia, and intellectual disability. Recent evidence suggests that dysfunctional CYFIP1 (cytoplasmic FMR1 interacting protein 1) contributes to the clinical phenotypes observed in individuals with 15q11.2 deletion/duplication syndrome. CYFIP1 plays crucial roles in neuronal development and brain connectivity, promoting actin polymerization and regulating local protein synthesis. However, information about the impact of single nucleotide variants in CYFIP1 on neurodevelopmental disorders is limited. METHODS Here, we report a family with 2 probands exhibiting intellectual disability, autism spectrum disorder, spastic tetraparesis, and brain morphology defects and who carry biallelic missense point mutations in the CYFIP1 gene. We used skin fibroblasts from one of the probands, the parents, and typically developing individuals to investigate the effect of the variants on the functionality of CYFIP1. In addition, we generated Drosophila knockin mutants to address the effect of the variants in vivo and gain insight into the molecular mechanism that underlies the clinical phenotype. RESULTS Our study revealed that the 2 missense variants are in protein domains responsible for maintaining the interaction within the wave regulatory complex. Molecular and cellular analyses in skin fibroblasts from one proband showed deficits in actin polymerization. The fly model for these mutations exhibited abnormal brain morphology and F-actin loss and recapitulated the core behavioral symptoms, such as deficits in social interaction and motor coordination. CONCLUSIONS Our findings suggest that the 2 CYFIP1 variants contribute to the clinical phenotype in the probands that reflects deficits in actin-mediated brain development processes.
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Affiliation(s)
- Vittoria Mariano
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland; Department of Human Genetics, KU Leuven, Belgium
| | | | - Carlotta Ricci
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Daniele Di Marino
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center, Polytechnic University of Marche, Ancona, Italy; Department of Neuroscience, Neuronal Death and Neuroprotection Unit, Mario Negri Institute for Pharmacological Research-IRCCS, Milan, Italy
| | | | - Sebastian Dupraz
- Axonal Growth and Regeneration Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Frank Bradke
- Axonal Growth and Regeneration Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Tilmann Achsel
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Eric Legius
- Department of Human Genetics, KU Leuven, Belgium
| | - Sylvie Odent
- Service de Génétique Clinique, Centre Labellisé pour les Anomalies du Développement Ouest, Centre Hospitalier Universitaire de Rennes, Rennes, France; Institut de Génétique et Développement de Rennes, CNRS, UMR 6290, Université de Rennes, ERN-ITHACA, France
| | - Pierre Billuart
- Institut de Psychiatrie et de Neurosciences de Paris, Institut National de la Santé et de la Recherche Médicale U1266, Université de Paris Cité (UPC), Paris, France
| | - Thierry Bienvenu
- Institut de Psychiatrie et de Neurosciences de Paris, Institut National de la Santé et de la Recherche Médicale U1266, Université de Paris Cité (UPC), Paris, France
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland; Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
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Chatterjee M, Roschitzki B, Grossmann J, Rathinam M, Kunz L, Wolski W, Panse C, Yadav J, Schlapbach R, Rao U, Sreevathsa R. Developmental stage-specific proteome analysis of the legume pod borer Maruca vitrata provides insights on relevant proteins. Int J Biol Macromol 2024; 254:127666. [PMID: 37890743 DOI: 10.1016/j.ijbiomac.2023.127666] [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: 06/23/2023] [Revised: 08/31/2023] [Accepted: 10/23/2023] [Indexed: 10/29/2023]
Abstract
The spotted pod borer, Maruca vitrata (Lepidoptera: Crambidae) is a destructive insect pest that inflicts significant productivity losses on important leguminous crops. Unravelling insect proteomes is vital to comprehend their fundamental molecular mechanisms. This research delved into the proteome profiles of four distinct stages -three larval and pupa of M. vitrata, utilizing LC-MS/MS label-free quantification-based methods. Employing comprehensive proteome analysis with fractionated datasets, we mapped 75 % of 3459 Drosophila protein orthologues out of which 2695 were identified across all developmental stages while, 137 and 94 were exclusive to larval and pupal stages respectively. Cluster analysis of 2248 protein orthologues derived from MaxQuant quantitative dataset depicted six clusters based on expression pattern similarity across stages. Consequently, gene ontology and protein-protein interaction network analyses using STRING database identified cluster 1 (58 proteins) and cluster 6 (25 proteins) associated with insect immune system and lipid metabolism. Furthermore, qRT-PCR-based expression analyses of ten selected proteins-coding genes authenticated the proteome data. Subsequently, functional validation of these chosen genes through gene silencing reduced their transcript abundance accompanied by a marked increase in mortality among dsRNA-injected larvae. Overall, this is a pioneering study to effectively develop a proteome atlas of M. vitrata as a potential resource for crop protection programs.
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Affiliation(s)
- Madhurima Chatterjee
- Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Bernd Roschitzki
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Jonas Grossmann
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Swiss Institute of Bioinformatics, Quartier Sorge, Batiment Amphipole, 1015 Lausanne, Switzerland
| | - Maniraj Rathinam
- ICAR-National Institute for Plant Biotechnology, New Delhi, India
| | - Laura Kunz
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Witold Wolski
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Swiss Institute of Bioinformatics, Quartier Sorge, Batiment Amphipole, 1015 Lausanne, Switzerland
| | - Christian Panse
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Swiss Institute of Bioinformatics, Quartier Sorge, Batiment Amphipole, 1015 Lausanne, Switzerland
| | - Jyoti Yadav
- Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India
| | - Ralph Schlapbach
- Functional Genomics Center Zurich, University of Zurich/ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Uma Rao
- Division of Nematology, ICAR-Indian Agricultural Research Institute, New Delhi, India; Engrave Bio Labs Pvt.Ltd., Shanthipuram, Kukatpally, Hyderabad, India.
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6
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Petsakou A, Liu Y, Liu Y, Comjean A, Hu Y, Perrimon N. Cholinergic neurons trigger epithelial Ca 2+ currents to heal the gut. Nature 2023; 623:122-131. [PMID: 37722602 PMCID: PMC10699467 DOI: 10.1038/s41586-023-06627-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 09/08/2023] [Indexed: 09/20/2023]
Abstract
A fundamental and unresolved question in regenerative biology is how tissues return to homeostasis after injury. Answering this question is essential for understanding the aetiology of chronic disorders such as inflammatory bowel diseases and cancer1. We used the Drosophila midgut2 to investigate this and discovered that during regeneration a subpopulation of cholinergic3 neurons triggers Ca2+ currents among intestinal epithelial cells, the enterocytes, to promote return to homeostasis. We found that downregulation of the conserved cholinergic enzyme acetylcholinesterase4 in the gut epithelium enables acetylcholine from specific Egr5 (TNF in mammals)-sensing cholinergic neurons to activate nicotinic receptors in innervated enterocytes. This activation triggers high Ca2+, which spreads in the epithelium through Innexin2-Innexin7 gap junctions6, promoting enterocyte maturation followed by reduction of proliferation and inflammation. Disrupting this process causes chronic injury consisting of ion imbalance, Yki (YAP in humans) activation7, cell death and increase of inflammatory cytokines reminiscent of inflammatory bowel diseases8. Altogether, the conserved cholinergic pathway facilitates epithelial Ca2+ currents that heal the intestinal epithelium. Our findings demonstrate nerve- and bioelectric9-dependent intestinal regeneration and advance our current understanding of how a tissue returns to homeostasis after injury.
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Affiliation(s)
| | - Yifang Liu
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Ying Liu
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Aram Comjean
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Yanhui Hu
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Boston, MA, USA.
- Howard Hughes Medical Institute, Boston, MA, USA.
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7
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Gundermann DG, Lymer S, Blau J. A rapid and dynamic role for FMRP in the plasticity of adult neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.01.555985. [PMID: 37693612 PMCID: PMC10491314 DOI: 10.1101/2023.09.01.555985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Fragile X syndrome (FXS) is a neuro-developmental disorder caused by silencing Fmr1, which encodes the RNA-binding protein FMRP. Although Fmr1 is expressed in adult neurons, it has been challenging to separate acute from chronic effects of loss of Fmr1 in models of FXS. We have used the precision of Drosophila genetics to test if Fmr1 acutely affects adult neuronal plasticity in vivo, focusing on the s-LNv circadian pacemaker neurons that show 24 hour rhythms in structural plasticity. We found that over-expressing Fmr1 for only 4 hours blocks the activity-dependent expansion of s-LNv projections without altering the circadian clock or activity-regulated gene expression. Conversely, acutely reducing Fmr1 expression prevented s-LNv projections from retracting. One FMRP target that we identified in s-LNvs is sif, which encodes a Rac1 GEF. Our data indicate that FMRP normally reduces sif mRNA translation at dusk to reduce Rac1 activity. Overall, our data reveal a previously unappreciated rapid and direct role for FMRP in acutely regulating neuronal plasticity in adult neurons, and underscore the importance of RNA-binding proteins in this process.
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Affiliation(s)
- Daniel G Gundermann
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
| | - Seana Lymer
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
- Current address: Proteintech Genomics, 11588 Sorrento Valley Rd, San Diego, CA 92121
| | - Justin Blau
- Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, UAE
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8
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Morena da Silva F, Lim S, Cabrera AR, Schrems ER, Jones RG, Rosa-Caldwell ME, Washington TA, Murach KA, Greene NP. The time-course of cancer cachexia onset reveals biphasic transcriptional disruptions in female skeletal muscle distinct from males. BMC Genomics 2023; 24:374. [PMID: 37403010 DOI: 10.1186/s12864-023-09462-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 06/17/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Cancer-cachexia (CC) is a debilitating condition affecting up to 80% of cancer patients and contributing to 40% of cancer-related deaths. While evidence suggests biological sex differences in the development of CC, assessments of the female transcriptome in CC are lacking, and direct comparisons between sexes are scarce. This study aimed to define the time course of Lewis lung carcinoma (LLC)-induced CC in females using transcriptomics, while directly comparing biological sex differences. RESULTS We found the global gene expression of the gastrocnemius muscle of female mice revealed biphasic transcriptomic alterations, with one at 1 week following tumor allograft and another during the later stages of cachexia development. The early phase was associated with the upregulation of extracellular-matrix pathways, while the later phase was characterized by the downregulation of oxidative phosphorylation, electron transport chain, and TCA cycle. When DEGs were compared to a known list of mitochondrial genes (MitoCarta), ~ 47% of these genes were differently expressed in females exhibiting global cachexia, suggesting transcriptional changes to mitochondrial gene expression happens concomitantly to functional impairments previously published. In contrast, the JAK-STAT pathway was upregulated in both the early and late stages of CC. Additionally, we observed a consistent downregulation of Type-II Interferon signaling genes in females, which was associated with protection in skeletal muscle atrophy despite systemic cachexia. Upregulation of Interferon signaling was noted in the gastrocnemius muscle of cachectic and atrophic male mice. Comparison of female tumor-bearing mice with males revealed ~ 70% of DEGs were distinct between sexes in cachectic animals, demonstrating dimorphic mechanisms of CC. CONCLUSION Our findings suggest biphasic disruptions in the transcriptome of female LLC tumor-bearing mice: an early phase associated with ECM remodeling and a late phase, accompanied by the onset of systemic cachexia, affecting overall muscle energy metabolism. Notably, ~ 2/3 of DEGs in CC are biologically sex-specific, providing evidence of dimorphic mechanisms of cachexia between sexes. Downregulation of Type-II Interferon signaling genes appears specific to CC development in females, suggesting a new biological sex-specific marker of CC not reliant on the loss of muscle mass, that might represent a protective mechanism against muscle loss in CC in female mice.
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Affiliation(s)
- Francielly Morena da Silva
- Cachexia Research Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Seongkyun Lim
- Cachexia Research Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Ana Regina Cabrera
- Cachexia Research Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Eleanor R Schrems
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Ronald G Jones
- Molecular Muscle Mass Regulation Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Megan E Rosa-Caldwell
- Cachexia Research Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Tyrone A Washington
- Exercise Muscle Biology Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Kevin A Murach
- Molecular Muscle Mass Regulation Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA.
| | - Nicholas P Greene
- Cachexia Research Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA.
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9
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Zheng Y, Liu C, Wang S, Qian K, Feng Y, Yu F, Wang J. Genome-wide analysis of cuticle protein family genes in rice stem borer Chilo suppressalis: Insights into their role in environmental adaptation and insecticidal stress response. Int J Biol Macromol 2023:124989. [PMID: 37244330 DOI: 10.1016/j.ijbiomac.2023.124989] [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: 03/27/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/29/2023]
Abstract
Insect cuticle plays a key role in insect survival, adaptation and prosperity by serving as the exoskeleton and the first barrier against environmental stresses. As the major components of insect cuticle, the diverse structural cuticle proteins (CPs) contribute to variation in physical properties and functions of cuticle. However, the roles of CPs in cuticular versatility, especially in the stress response or adaption, remain incompletely understood. In this study, we performed a genome-wide analysis of CP superfamily in the rice-boring pest Chilo suppressalis. A total of 211 CP genes were identified and their encoding proteins were classified into eleven families and three subfamilies (RR1, RR2, and RR3). The comparative genomic analysis of CPs revealed that C. suppressalis had fewer CP genes compared to other lepidopteran species, which largely resulted from a less expansion of his-rich RR2 genes involved in cuticular sclerotization, suggesting long-term boring life of C. suppressalis inside rice hosts might evolutionarily prefer cuticular elasticity rather than cuticular sclerotization. We also investigated the response pattern of all CP genes under insecticidal stresses. >50 % CsCPs were upregulated at least 2-fold under insecticidal stresses. Notably, the majority of the highly upregulated CsCPs formed gene pairs or gene clusters on chromosomes, indicating the rapid response of adjacent CsCPs to insecticidal stress. Most high-response CsCPs encoded AAPA/V/L motifs that are related to cuticular elasticity and >50 % of the sclerotization-related his-rich RR2 genes were also upregulated. These results suggested the potential roles of CsCPs in balancing the elasticity and sclerotization of cuticles, which is essential for the survival and adaptation of plant borers including C. suppressalis. Our study provides valuable information for further developing cuticle-based strategies of both pest management and biomimetic applications.
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Affiliation(s)
- Yang Zheng
- College of Plant Protection, Yangzhou University, Yangzhou, China.
| | - Changpeng Liu
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Shuang Wang
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Kun Qian
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Yinghao Feng
- College of Plant Protection, Yangzhou University, Yangzhou, China
| | - Fuhai Yu
- School of Chemistry, Chemical Engineering and Materials, Jining University, Qufu 273155, Shandong, China
| | - Jianjun Wang
- College of Plant Protection, Yangzhou University, Yangzhou, China
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10
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Vaughen JP, Theisen E, Clandinin TR. From seconds to days: Neural plasticity viewed through a lipid lens. Curr Opin Neurobiol 2023; 80:102702. [PMID: 36965206 DOI: 10.1016/j.conb.2023.102702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/31/2023] [Accepted: 02/16/2023] [Indexed: 03/27/2023]
Abstract
Many adult neurons are dynamically remodeled across timescales ranging from the rapid addition and removal of specific synaptic connections, to largescale structural plasticity events that reconfigure circuits over hours, days, and months. Membrane lipids, including brain-enriched sphingolipids, play crucial roles in these processes. In this review, we summarize progress at the intersection of neuronal activity, lipids, and structural remodeling. We highlight how brain activity modulates lipid metabolism to enable adaptive structural plasticity, and showcase glia as key players in membrane remodeling. These studies reveal that lipids act as critical signaling molecules that instruct the dynamic architecture of the brain.
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Affiliation(s)
- John P Vaughen
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, United States; Department of Developmental Biology, Stanford University, Stanford, CA, 94305, United States. https://twitter.com/gliaful
| | - Emma Theisen
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, United States. https://twitter.com/emmaktheisen
| | - Thomas R Clandinin
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, United States.
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11
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Van Drunen R, Eckel-Mahan K. Circadian rhythms as modulators of brain health during development and throughout aging. Front Neural Circuits 2023; 16:1059229. [PMID: 36741032 PMCID: PMC9893507 DOI: 10.3389/fncir.2022.1059229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 12/08/2022] [Indexed: 01/20/2023] Open
Abstract
The circadian clock plays a prominent role in neurons during development and throughout aging. This review covers topics pertinent to the role of 24-h rhythms in neuronal development and function, and their tendency to decline with aging. Pharmacological or behavioral modification that augment the function of our internal clock may be central to decline of cognitive disease and to future chronotherapy for aging-related diseases of the central nervous system.
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12
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Vaughen JP, Theisen E, Rivas-Serna IM, Berger AB, Kalakuntla P, Anreiter I, Mazurak VC, Rodriguez TP, Mast JD, Hartl T, Perlstein EO, Reimer RJ, Clandinin MT, Clandinin TR. Glial control of sphingolipid levels sculpts diurnal remodeling in a circadian circuit. Neuron 2022; 110:3186-3205.e7. [PMID: 35961319 PMCID: PMC10868424 DOI: 10.1016/j.neuron.2022.07.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/21/2022] [Accepted: 07/14/2022] [Indexed: 11/19/2022]
Abstract
Structural plasticity in the brain often necessitates dramatic remodeling of neuronal processes, with attendant reorganization of the cytoskeleton and membranes. Although cytoskeletal restructuring has been studied extensively, how lipids might orchestrate structural plasticity remains unclear. We show that specific glial cells in Drosophila produce glucocerebrosidase (GBA) to locally catabolize sphingolipids. Sphingolipid accumulation drives lysosomal dysfunction, causing gba1b mutants to harbor protein aggregates that cycle across circadian time and are regulated by neural activity, the circadian clock, and sleep. Although the vast majority of membrane lipids are stable across the day, a specific subset that is highly enriched in sphingolipids cycles daily in a gba1b-dependent fashion. Remarkably, both sphingolipid biosynthesis and degradation are required for the diurnal remodeling of circadian clock neurites, which grow and shrink across the day. Thus, dynamic sphingolipid regulation by glia enables diurnal circuit remodeling and proper circadian behavior.
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Affiliation(s)
- John P Vaughen
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - Emma Theisen
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA
| | - Irma Magaly Rivas-Serna
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Andrew B Berger
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA
| | - Prateek Kalakuntla
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - Ina Anreiter
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA
| | - Vera C Mazurak
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | | | - Joshua D Mast
- Perlara PBC, 2625 Alcatraz Ave #435, Berkeley, CA 94705, USA
| | - Tom Hartl
- Perlara PBC, 2625 Alcatraz Ave #435, Berkeley, CA 94705, USA
| | | | - Richard J Reimer
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - M Thomas Clandinin
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Thomas R Clandinin
- Department of Neurobiology, Stanford University, Stanford, CA 94305, USA.
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13
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Perry A, McGaugh SE, Keene AC, Blackmon H. CaveCrawler: an interactive analysis suite for cavefish bioinformatics. G3 GENES|GENOMES|GENETICS 2022; 12:6609176. [PMID: 35708643 PMCID: PMC9339328 DOI: 10.1093/g3journal/jkac132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 05/10/2022] [Indexed: 11/13/2022]
Abstract
The growing use of genomics in diverse organisms provides the basis for identifying genomic and transcriptional differences across species and experimental conditions. Databases containing genomic and functional data have played critical roles in the development of numerous genetic models but most emerging models lack such databases. The Mexican tetra, Astyanax mexicanus exists as 2 morphs: surface-dwelling and cave-dwelling. There exist at least 30 cave populations, providing a system to study convergent evolution. We have generated a web-based analysis suite that integrates datasets from different studies to identify how gene transcription and genetic markers of selection differ between populations and across experimental contexts. Results of diverse studies can be analyzed in conjunction with other genetic data (e.g. Gene Ontology information), to enable biological inference from cross-study patterns and identify future avenues of research. Furthermore, the framework that we have built for A. mexicanus can be adapted for other emerging model systems.
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Affiliation(s)
- Annabel Perry
- Department of Biology, Texas A&M University , College Station, TX 77843, USA
| | - Suzanne E McGaugh
- Department of Ecology, Evolution, and Behavior, University of Minnesota , Saint Paul, MN 55108, USA
| | - Alex C Keene
- Department of Biology, Texas A&M University , College Station, TX 77843, USA
| | - Heath Blackmon
- Department of Biology, Texas A&M University , College Station, TX 77843, USA
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14
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Shafer OT, Gutierrez GJ, Li K, Mildenhall A, Spira D, Marty J, Lazar AA, Fernandez MDLP. ---Connectomic analysis of the Drosophila lateral neuron clock cells reveals the synaptic basis of functional pacemaker classes. eLife 2022; 11:79139. [PMID: 35766361 PMCID: PMC9365390 DOI: 10.7554/elife.79139] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/29/2022] [Indexed: 11/23/2022] Open
Abstract
The circadian clock orchestrates daily changes in physiology and behavior to ensure internal temporal order and optimal timing across the day. In animals, a central brain clock coordinates circadian rhythms throughout the body and is characterized by a remarkable robustness that depends on synaptic connections between constituent neurons. The clock neuron network of Drosophila, which shares network motifs with clock networks in the mammalian brain yet is built of many fewer neurons, offers a powerful model for understanding the network properties of circadian timekeeping. Here, we report an assessment of synaptic connectivity within a clock network, focusing on the critical lateral neuron (LN) clock neuron classes within the Janelia hemibrain dataset. Our results reveal that previously identified anatomical and functional subclasses of LNs represent distinct connectomic types. Moreover, we identify a small number of non-clock cell subtypes representing highly synaptically coupled nodes within the clock neuron network. This suggests that neurons lacking molecular timekeeping likely play integral roles within the circadian timekeeping network. To our knowledge, this represents the first comprehensive connectomic analysis of a circadian neuronal network. Most organisms on Earth possess an internal timekeeping system which ensures that bodily processes such as sleep, wakefulness or digestion take place at the right time. These precise daily rhythms are kept in check by a master clock in the brain. There, thousands of neurons – some of which carrying an internal ‘molecular clock’ – connect to each other through structures known as synapses. Exactly how the resulting network is organised to support circadian timekeeping remains unclear. To explore this question, Shafer, Gutierrez et al. focused on fruit flies, as recent efforts have systematically mapped every neuron and synaptic connection in the brain of this model organism. Analysing available data from the hemibrain connectome project at Janelia revealed that that the neurons with the most important timekeeping roles were in fact forming the fewest synapses within the network. In addition, neurons without internal molecular clocks mediated strong synaptic connections between those that did, suggesting that ‘clockless’ cells still play an integral role in circadian timekeeping. With this research, Shafer, Gutierrez et al. provide unexpected insights into the organisation of the master body clock. Better understanding the networks that underpin circadian rhythms will help to grasp how and why these are disrupted in obesity, depression and Alzheimer’s disease.
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Affiliation(s)
- Orie T Shafer
- Advanced Science Research Center, City University of New York, New York, United States
| | - Gabrielle J Gutierrez
- Center for Theoretical Neuroscience, Columbia University, New York City, United States
| | - Kimberly Li
- Department of Neuroscience and Behavior, Barnard College, New York, United States
| | - Amber Mildenhall
- Department of Neuroscience and Behavior, Barnard College, New York, United States
| | - Daphna Spira
- Center for Theoretical Neuroscience, Columbia University, New York City, United States
| | - Jonathan Marty
- Department of Electrical Engineering, Columbia University, New York, United States
| | - Aurel A Lazar
- Department of Electrical Engineering, Columbia University, New York, United States
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15
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Seng C, Luo W, Földy C. Circuit formation in the adult brain. Eur J Neurosci 2022; 56:4187-4213. [PMID: 35724981 PMCID: PMC9546018 DOI: 10.1111/ejn.15742] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 06/08/2022] [Accepted: 06/09/2022] [Indexed: 11/30/2022]
Abstract
Neurons in the mammalian central nervous system display an enormous capacity for circuit formation during development but not later in life. In principle, new circuits could be also formed in adult brain, but the absence of the developmental milieu and the presence of growth inhibition and hundreds of working circuits are generally viewed as unsupportive for such a process. Here, we bring together evidence from different areas of neuroscience—such as neurological disorders, adult‐brain neurogenesis, innate behaviours, cell grafting, and in vivo cell reprogramming—which demonstrates robust circuit formation in adult brain. In some cases, adult‐brain rewiring is ongoing and required for certain types of behaviour and memory, while other cases show significant promise for brain repair in disease models. Together, these examples highlight that the adult brain has higher capacity for structural plasticity than previously recognized. Understanding the underlying mechanisms behind this retained plasticity has the potential to advance basic knowledge regarding the molecular organization of synaptic circuits and could herald a new era of neural circuit engineering for therapeutic repair.
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Affiliation(s)
- Charlotte Seng
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zurich, Zürich, Switzerland
| | - Wenshu Luo
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zurich, Zürich, Switzerland
| | - Csaba Földy
- Laboratory of Neural Connectivity, Brain Research Institute, Faculties of Medicine and Science, University of Zurich, Zürich, Switzerland
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16
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Duhart JC, Mosca TJ. Genetic regulation of central synapse formation and organization in Drosophila melanogaster. Genetics 2022; 221:6597078. [PMID: 35652253 DOI: 10.1093/genetics/iyac078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/29/2022] [Indexed: 01/04/2023] Open
Abstract
A goal of modern neuroscience involves understanding how connections in the brain form and function. Such a knowledge is essential to inform how defects in the exquisite complexity of nervous system growth influence neurological disease. Studies of the nervous system in the fruit fly Drosophila melanogaster enabled the discovery of a wealth of molecular and genetic mechanisms underlying development of synapses-the specialized cell-to-cell connections that comprise the essential substrate for information flow and processing in the nervous system. For years, the major driver of knowledge was the neuromuscular junction due to its ease of examination. Analogous studies in the central nervous system lagged due to a lack of genetic accessibility of specific neuron classes, synaptic labels compatible with cell-type-specific access, and high resolution, quantitative imaging strategies. However, understanding how central synapses form remains a prerequisite to understanding brain development. In the last decade, a host of new tools and techniques extended genetic studies of synapse organization into central circuits to enhance our understanding of synapse formation, organization, and maturation. In this review, we consider the current state-of-the-field. We first discuss the tools, technologies, and strategies developed to visualize and quantify synapses in vivo in genetically identifiable neurons of the Drosophila central nervous system. Second, we explore how these tools enabled a clearer understanding of synaptic development and organization in the fly brain and the underlying molecular mechanisms of synapse formation. These studies establish the fly as a powerful in vivo genetic model that offers novel insights into neural development.
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Affiliation(s)
- Juan Carlos Duhart
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Timothy J Mosca
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
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17
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Buhl E, Kim YA, Parsons T, Zhu B, Santa-Maria I, Lefort R, Hodge JJ. Effects of Eph/ephrin signalling and human Alzheimer's disease-associated EphA1 on behaviour and neurophysiology. Neurobiol Dis 2022; 170:105752. [DOI: 10.1016/j.nbd.2022.105752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 04/09/2022] [Accepted: 05/09/2022] [Indexed: 12/13/2022] Open
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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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The E3 ubiquitin ligase adaptor Tango10 links the core circadian clock to neuropeptide and behavioral rhythms. Proc Natl Acad Sci U S A 2021; 118:2110767118. [PMID: 34799448 PMCID: PMC8617488 DOI: 10.1073/pnas.2110767118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/04/2021] [Indexed: 11/18/2022] Open
Abstract
Circadian transcriptional timekeepers in pacemaker neurons drive profound daily rhythms in sleep and wake. Here we reveal a molecular pathway that links core transcriptional oscillators to neuronal and behavioral rhythms. Using two independent genetic screens, we identified mutants of Transport and Golgi organization 10 (Tango10) with poor behavioral rhythmicity. Tango10 expression in pacemaker neurons expressing the neuropeptide PIGMENT-DISPERSING FACTOR (PDF) is required for robust rhythms. Loss of Tango10 results in elevated PDF accumulation in nerve terminals even in mutants lacking a functional core clock. TANGO10 protein itself is rhythmically expressed in PDF terminals. Mass spectrometry of TANGO10 complexes reveals interactions with the E3 ubiquitin ligase CULLIN 3 (CUL3). CUL3 depletion phenocopies Tango10 mutant effects on PDF even in the absence of the core clock gene timeless Patch clamp electrophysiology in Tango10 mutant neurons demonstrates elevated spontaneous firing potentially due to reduced voltage-gated Shaker-like potassium currents. We propose that Tango10/Cul3 transduces molecular oscillations from the core clock to neuropeptide release important for behavioral rhythms.
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20
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Decapentaplegic Acutely Defines the Connectivity of Central Pacemaker Neurons in Drosophila. J Neurosci 2021; 41:8338-8350. [PMID: 34429376 DOI: 10.1523/jneurosci.0397-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 07/12/2021] [Accepted: 08/11/2021] [Indexed: 11/21/2022] Open
Abstract
Rhythmic rest-activity cycles are controlled by an endogenous clock. In Drosophila, this clock resides in ∼150 neurons organized in clusters whose hierarchy changes in response to environmental conditions. The concerted activity of the circadian network is necessary for the adaptive responses to synchronizing environmental stimuli. Thus far, work was devoted to unravel the logic of the coordination of different clusters focusing on neurotransmitters and neuropeptides. We further explored communication in the adult male brain through ligands belonging to the bone morphogenetic protein (BMP) pathway. Herein we show that the lateral ventral neurons (LNvs) express the small morphogen decapentaplegic (DPP). DPP expression in the large LNvs triggered a period lengthening phenotype, the downregulation of which caused reduced rhythmicity and affected anticipation at dawn and dusk, underscoring DPP per se conveys time-of-day relevant information. Surprisingly, DPP expression in the large LNvs impaired circadian remodeling of the small LNv axonal terminals, likely through local modulation of the guanine nucleotide exchange factor Trio. These findings open the provocative possibility that the BMP pathway is recruited to strengthen/reduce the connectivity among specific clusters along the day and thus modulate the contribution of the clusters to the circadian network.SIGNIFICANCE STATEMENT The circadian clock relies on the communication between groups of so-called clock neurons to coordinate physiology and behavior to the optimal times across the day, predicting and adapting to a changing environment. The circadian network relies on neurotransmitters and neuropeptides to fine-tune connectivity among clock neurons and thus give rise to a coherent output. Herein we show that decapentaplegic, a ligand belonging to the BMP retrograde signaling pathway required for coordinated growth during development, is recruited by a group of circadian neurons in the adult brain to trigger structural remodeling of terminals on a daily basis.
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21
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Abstract
Circadian clocks are biochemical time-keeping machines that synchronize animal behavior and physiology with planetary rhythms. In Drosophila, the core components of the clock comprise a transcription/translation feedback loop and are expressed in seven neuronal clusters in the brain. Although it is increasingly evident that the clocks in each of the neuronal clusters are regulated differently, how these clocks communicate with each other across the circadian neuronal network is less clear. Here, we review the latest evidence that describes the physical connectivity of the circadian neuronal network . Using small ventral lateral neurons as a starting point, we summarize how one clock may communicate with another, highlighting the signaling pathways that are both upstream and downstream of these clocks. We propose that additional efforts are required to understand how temporal information generated in each circadian neuron is integrated across a neuronal circuit to regulate rhythmic behavior.
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Affiliation(s)
- Myra Ahmad
- Department of Pediatrics, Division of Medical Genetics, Dalhousie University, Halifax, NS, Canada
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
| | - Wanhe Li
- Laboratory of Genetics, The Rockefeller University, New York, NY, USA
| | - Deniz Top
- Department of Pediatrics, Division of Medical Genetics, Dalhousie University, Halifax, NS, Canada
- Department of Pharmacology, Dalhousie University, Halifax, NS, Canada
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22
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Song BJ, Sharp SJ, Rogulja D. Daily rewiring of a neural circuit generates a predictive model of environmental light. SCIENCE ADVANCES 2021; 7:7/13/eabe4284. [PMID: 33762336 PMCID: PMC7990339 DOI: 10.1126/sciadv.abe4284] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 02/03/2021] [Indexed: 05/02/2023]
Abstract
Behavioral responsiveness to external stimulation is shaped by context. We studied how sensory information can be contextualized, by examining light-evoked locomotor responsiveness of Drosophila relative to time of day. We found that light elicits an acute increase in locomotion (startle) that is modulated in a time-of-day-dependent manner: Startle is potentiated during the nighttime, when light is unexpected, but is suppressed during the daytime. The internal daytime-nighttime context is generated by two interconnected and functionally opposing populations of circadian neurons-LNvs generating the daytime state and DN1as generating the nighttime state. Switching between the two states requires daily remodeling of LNv and DN1a axons such that the maximum presynaptic area in one population coincides with the minimum in the other. We propose that a dynamic model of environmental light resides in the shifting connectivities of the LNv-DN1a circuit, which helps animals evaluate ongoing conditions and choose a behavioral response.
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Affiliation(s)
- Bryan J Song
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Slater J Sharp
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Dragana Rogulja
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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23
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Ma D, Przybylski D, Abruzzi KC, Schlichting M, Li Q, Long X, Rosbash M. A transcriptomic taxonomy of Drosophila circadian neurons around the clock. eLife 2021; 10:63056. [PMID: 33438579 PMCID: PMC7837698 DOI: 10.7554/elife.63056] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 01/11/2021] [Indexed: 01/19/2023] Open
Abstract
Many different functions are regulated by circadian rhythms, including those orchestrated by discrete clock neurons within animal brains. To comprehensively characterize and assign cell identity to the 75 pairs of Drosophila circadian neurons, we optimized a single-cell RNA sequencing method and assayed clock neuron gene expression at different times of day. The data identify at least 17 clock neuron categories with striking spatial regulation of gene expression. Transcription factor regulation is prominent and likely contributes to the robust circadian oscillation of many transcripts, including those that encode cell-surface proteins previously shown to be important for cell recognition and synapse formation during development. The many other clock-regulated genes also constitute an important resource for future mechanistic and functional studies between clock neurons and/or for temporal signaling to circuits elsewhere in the fly brain.
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Affiliation(s)
- Dingbang Ma
- Howard Hughes Medical Institute, Brandeis University, Waltham, United States
| | - Dariusz Przybylski
- Howard Hughes Medical Institute, Brandeis University, Waltham, United States
| | - Katharine C Abruzzi
- Howard Hughes Medical Institute, Brandeis University, Waltham, United States
| | | | - Qunlong Li
- Howard Hughes Medical Institute, Brandeis University, Waltham, United States
| | - Xi Long
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, United States
| | - Michael Rosbash
- Howard Hughes Medical Institute, Brandeis University, Waltham, United States
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24
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Kula-Eversole E, Lee DH, Samba I, Yildirim E, Levine DC, Hong HK, Lear BC, Bass J, Rosbash M, Allada R. Phosphatase of Regenerating Liver-1 Selectively Times Circadian Behavior in Darkness via Function in PDF Neurons and Dephosphorylation of TIMELESS. Curr Biol 2021; 31:138-149.e5. [PMID: 33157022 PMCID: PMC7855481 DOI: 10.1016/j.cub.2020.10.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 08/25/2020] [Accepted: 10/07/2020] [Indexed: 12/31/2022]
Abstract
The timing of behavior under natural light-dark conditions is a function of circadian clocks and photic input pathways, but a mechanistic understanding of how these pathways collaborate in animals is lacking. Here we demonstrate in Drosophila that the Phosphatase of Regenerating Liver-1 (PRL-1) sets period length and behavioral phase gated by photic signals. PRL-1 knockdown in PDF clock neurons dramatically lengthens circadian period. PRL-1 mutants exhibit allele-specific interactions with the light- and clock-regulated gene timeless (tim). Moreover, we show that PRL-1 promotes TIM accumulation and dephosphorylation. Interestingly, the PRL-1 mutant period lengthening is suppressed in constant light, and PRL-1 mutants display a delayed phase under short, but not long, photoperiod conditions. Thus, our studies reveal that PRL-1-dependent dephosphorylation of TIM is a core mechanism of the clock that sets period length and phase in darkness, enabling the behavioral adjustment to change day-night cycles.
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Affiliation(s)
| | - Da Hyun Lee
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Ima Samba
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Evrim Yildirim
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Daniel C Levine
- Department of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Hee-Kyung Hong
- Department of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Bridget C Lear
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA
| | - Joseph Bass
- Department of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Michael Rosbash
- Howard Hughes Medical Institute, Department of Biology, Brandeis University, Waltham, MA 02445, USA
| | - Ravi Allada
- Department of Neurobiology, Northwestern University, Evanston, IL 60208, USA.
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25
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Weil T, Ometto L, Esteve-Codina A, Gómez-Garrido J, Oppedisano T, Lotti C, Dabad M, Alioto T, Vrhovsek U, Hogenhout S, Anfora G. Linking omics and ecology to dissect interactions between the apple proliferation phytoplasma and its psyllid vector Cacopsylla melanoneura. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 127:103474. [PMID: 33007407 DOI: 10.1016/j.ibmb.2020.103474] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 09/08/2020] [Accepted: 09/17/2020] [Indexed: 06/11/2023]
Abstract
Phytoplasmas are bacterial plant pathogens that are detrimental to many plants and cause devastating effects on crops. They are not viable outside their host plants and depend on specific insect vectors for their transmission. So far, research has largely focused on plant-pathogen interactions, while the complex interactions between phytoplasmas and insect vectors are far less understood. Here, we used next-generation sequencing to investigate how transcriptional profiles of the vector psyllid Cacopsylla melanoneura (Hemiptera, Psyllidae) are altered during infection by the bacterium Candidatus Phytoplasma mali (P. mali), which causes the economically important apple proliferation disease. This first de novo transcriptome assembly of an apple proliferation vector revealed that mainly genes involved in small GTPase mediated signal transduction, nervous system development, adhesion, reproduction, actin-filament based and rhythmic processes are significantly altered upon P. mali infection. Furthermore, the presence of P. mali is accompanied by significant changes in carbohydrate and polyol levels, as revealed by metabolomics analysis. Taken together, our results suggest that infection with P. mali impacts on the insect vector physiology, which in turn likely affects the ability of the vector to transmit phytoplasma.
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Affiliation(s)
- Tobias Weil
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy.
| | - Lino Ometto
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy; Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Anna Esteve-Codina
- CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain
| | - Jèssica Gómez-Garrido
- CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain
| | - Tiziana Oppedisano
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy; Present address: Hermiston Agricultural Research and Extension Center, Oregon State University, Hermiston (OR, USA
| | - Cesare Lotti
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy
| | - Marc Dabad
- CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain
| | - Tyler Alioto
- CNAG-CRG, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08028, Barcelona, Spain; Universitat Pompeu Fabra (UPF), 08003, Barcelona, Spain
| | - Urska Vrhovsek
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy
| | - Saskia Hogenhout
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK
| | - Gianfranco Anfora
- Research and Innovation Center, Fondazione E. Mach, 38010, San Michele all'Adige (TN), Italy; Centre Agriculture Food Environment, University of Trento, 38010, San Michele all'Adige (TN), Italy
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26
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High-Frequency Neuronal Bursting is Essential for Circadian and Sleep Behaviors in Drosophila. J Neurosci 2020; 41:689-710. [PMID: 33262246 DOI: 10.1523/jneurosci.2322-20.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/04/2020] [Accepted: 11/09/2020] [Indexed: 02/08/2023] Open
Abstract
Circadian rhythms have been extensively studied in Drosophila; however, still little is known about how the electrical properties of clock neurons are specified. We have performed a behavioral genetic screen through the downregulation of candidate ion channels in the lateral ventral neurons (LNvs) and show that the hyperpolarization-activated cation current Ih is important for the behaviors that the LNvs influence: temporal organization of locomotor activity, analyzed in males, and sleep, analyzed in females. Using whole-cell patch clamp electrophysiology we demonstrate that small LNvs (sLNvs) are bursting neurons, and that Ih is necessary to achieve the high-frequency bursting firing pattern characteristic of both types of LNvs in females. Since firing in bursts has been associated to neuropeptide release, we hypothesized that Ih would be important for LNvs communication. Indeed, herein we demonstrate that Ih is fundamental for the recruitment of pigment dispersing factor (PDF) filled dense core vesicles (DCVs) to the terminals at the dorsal protocerebrum and for their timed release, and hence for the temporal coordination of circadian behaviors.SIGNIFICANCE STATEMENT Ion channels are transmembrane proteins with selective permeability to specific charged particles. The rich repertoire of parameters that may gate their opening state, such as voltage-sensitivity, modulation by second messengers and specific kinetics, make this protein family a determinant of neuronal identity. Ion channel structure is evolutionary conserved between vertebrates and invertebrates, making any discovery easily translatable. Through a screen to uncover ion channels with roles in circadian rhythms, we have identified the Ih channel as an important player in a subset of clock neurons of the fruit fly. We show that lateral ventral neurons (LNvs) need Ih to fire action potentials in a high-frequency bursting mode and that this is important for peptide transport and the control of behavior.
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Falcón J, Torriglia A, Attia D, Viénot F, Gronfier C, Behar-Cohen F, Martinsons C, Hicks D. Exposure to Artificial Light at Night and the Consequences for Flora, Fauna, and Ecosystems. Front Neurosci 2020; 14:602796. [PMID: 33304237 PMCID: PMC7701298 DOI: 10.3389/fnins.2020.602796] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/22/2020] [Indexed: 12/22/2022] Open
Abstract
The present review draws together wide-ranging studies performed over the last decades that catalogue the effects of artificial-light-at-night (ALAN) upon living species and their environment. We provide an overview of the tremendous variety of light-detection strategies which have evolved in living organisms - unicellular, plants and animals, covering chloroplasts (plants), and the plethora of ocular and extra-ocular organs (animals). We describe the visual pigments which permit photo-detection, paying attention to their spectral characteristics, which extend from the ultraviolet into infrared. We discuss how organisms use light information in a way crucial for their development, growth and survival: phototropism, phototaxis, photoperiodism, and synchronization of circadian clocks. These aspects are treated in depth, as their perturbation underlies much of the disruptive effects of ALAN. The review goes into detail on circadian networks in living organisms, since these fundamental features are of critical importance in regulating the interface between environment and body. Especially, hormonal synthesis and secretion are often under circadian and circannual control, hence perturbation of the clock will lead to hormonal imbalance. The review addresses how the ubiquitous introduction of light-emitting diode technology may exacerbate, or in some cases reduce, the generalized ever-increasing light pollution. Numerous examples are given of how widespread exposure to ALAN is perturbing many aspects of plant and animal behaviour and survival: foraging, orientation, migration, seasonal reproduction, colonization and more. We examine the potential problems at the level of individual species and populations and extend the debate to the consequences for ecosystems. We stress, through a few examples, the synergistic harmful effects resulting from the impacts of ALAN combined with other anthropogenic pressures, which often impact the neuroendocrine loops in vertebrates. The article concludes by debating how these anthropogenic changes could be mitigated by more reasonable use of available technology - for example by restricting illumination to more essential areas and hours, directing lighting to avoid wasteful radiation and selecting spectral emissions, to reduce impact on circadian clocks. We end by discussing how society should take into account the potentially major consequences that ALAN has on the natural world and the repercussions for ongoing human health and welfare.
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Affiliation(s)
- Jack Falcón
- Laboratoire Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), MNHN, CNRS FRE 2030, SU, IRD 207, UCN, UA, Paris, France
| | - Alicia Torriglia
- Centre de Recherche des Cordeliers, INSERM U 1138, Ophtalmopole Hôpital Cochin, Assistance Publique - Hôpitaux de Paris, Université de Paris - SU, Paris, France
| | - Dina Attia
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Maisons-Alfort, France
| | | | - Claude Gronfier
- Lyon Neuroscience Research Center (CRNL), Waking Team, Inserm UMRS 1028, CNRS UMR 5292, Université Claude Bernard Lyon 1, Lyon, France
| | - Francine Behar-Cohen
- Centre de Recherche des Cordeliers, INSERM U 1138, Ophtalmopole Hôpital Cochin, Assistance Publique - Hôpitaux de Paris, Université de Paris - SU, Paris, France
| | | | - David Hicks
- Inserm, CNRS, Institut des Neurosciences Cellulaires et Intégratives, Université de Strasbourg, Strasbourg, France
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Duhart JM, Herrero A, de la Cruz G, Ispizua JI, Pírez N, Ceriani MF. Circadian Structural Plasticity Drives Remodeling of E Cell Output. Curr Biol 2020; 30:5040-5048.e5. [PMID: 33065014 DOI: 10.1016/j.cub.2020.09.057] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/21/2020] [Accepted: 09/17/2020] [Indexed: 12/15/2022]
Abstract
Behavioral outputs arise as a result of highly regulated yet flexible communication among neurons. The Drosophila circadian network includes 150 neurons that dictate the temporal organization of locomotor activity; under light-dark (LD) conditions, flies display a robust bimodal pattern. The pigment-dispersing factor (PDF)-positive small ventral lateral neurons (sLNv) have been linked to the generation of the morning activity peak (the "M cells"), whereas the Cryptochrome (CRY)-positive dorsal lateral neurons (LNds) and the PDF-negative sLNv are necessary for the evening activity peak (the "E cells") [1, 2]. While each group directly controls locomotor output pathways [3], an interplay between them along with a third dorsal cluster (the DN1ps) is necessary for the correct timing of each peak and for adjusting behavior to changes in the environment [4-7]. M cells set the phase of roughly half of the circadian neurons (including the E cells) through PDF [5, 8-10]. Here, we show the existence of synaptic input provided by the evening oscillator onto the M cells. Both structural and functional approaches revealed that E-to-M cell connectivity changes across the day, with higher excitatory input taking place before the day-to-night transition. We identified two different neurotransmitters, acetylcholine and glutamate, released by E cells that are relevant for robust circadian output. Indeed, we show that acetylcholine is responsible for the excitatory input from E cells to M cells, which show preferential responsiveness to acetylcholine during the evening. Our findings provide evidence of an excitatory feedback between circadian clusters and unveil an important plastic remodeling of the E cells' synaptic connections.
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Affiliation(s)
- José M Duhart
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina
| | - Anastasia Herrero
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina
| | - Gabriel de la Cruz
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina
| | - Juan I Ispizua
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina
| | - Nicolás Pírez
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina
| | - M Fernanda Ceriani
- Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, Buenos Aires 1405-BWE, Argentina.
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Takenaka N, Nakao M, Hasegawa K, Chan MP, Satoh T. The guanine nucleotide exchange factor FLJ00068 activates Rac1 in adipocyte insulin signaling. FEBS Lett 2020; 594:4370-4380. [PMID: 32978791 DOI: 10.1002/1873-3468.13939] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/31/2020] [Accepted: 09/10/2020] [Indexed: 12/26/2022]
Abstract
Insulin stimulates glucose uptake via the translocation of the glucose transporter GLUT4 to the plasma membrane in adipocytes. Several lines of evidence suggest that the small GTPase Rac1 plays an important role in insulin-stimulated glucose uptake in skeletal muscle and adipocytes. The purpose of this study is to investigate the mechanisms whereby Rac1 is regulated in adipocyte insulin signaling. Here, we show that knockdown of the guanine nucleotide exchange factor FLJ00068 inhibits Rac1 activation and GLUT4 translocation by insulin and a constitutively activated form of the protein kinase Akt2. Furthermore, constitutively activated FLJ00068 induced Rac1 activation and Rac1-dependent GLUT4 translocation. Collectively, these results suggest the involvement of FLJ00068 downstream of Akt2 in insulin-stimulated glucose uptake signaling in adipocytes.
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Affiliation(s)
- Nobuyuki Takenaka
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Japan
| | - Mika Nakao
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Japan
| | - Kiko Hasegawa
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Japan
| | - Man Piu Chan
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Japan
| | - Takaya Satoh
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Japan
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Rouyer F, Chatterjee A. Circadian Clocks: Structural Plasticity on the Input Side. Curr Biol 2020; 30:R890-R893. [PMID: 32750352 DOI: 10.1016/j.cub.2020.06.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Key Drosophila clock neurons remodel their axonal arborization on a daily basis. The current view is that remodelling is part of the control of clock neuron output but new data support a major role in modulating sensory inputs.
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Affiliation(s)
- François Rouyer
- Institut des Neurosciences Paris-Saclay, Université Paris-Sud, Université Paris-Saclay, CNRS, 91190 Gif-sur-Yvette, France.
| | - Abhishek Chatterjee
- Institut des Neurosciences Paris-Saclay, Université Paris-Sud, Université Paris-Saclay, CNRS, 91190 Gif-sur-Yvette, France
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31
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Hartsock MJ, Spencer RL. Memory and the circadian system: Identifying candidate mechanisms by which local clocks in the brain may regulate synaptic plasticity. Neurosci Biobehav Rev 2020; 118:134-162. [PMID: 32712278 DOI: 10.1016/j.neubiorev.2020.07.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 07/14/2020] [Accepted: 07/18/2020] [Indexed: 12/11/2022]
Abstract
The circadian system is an endogenous biological network responsible for coordinating near-24-h cycles in behavior and physiology with daily timing cues from the external environment. In this review, we explore how the circadian system regulates memory formation, retention, and recall. Circadian rhythms in these memory processes may arise through several endogenous pathways, and recent work highlights the importance of genetic timekeepers found locally within tissues, called local clocks. We evaluate the circadian memory literature for evidence of local clock involvement in memory, identifying potential nodes for direct interactions between local clock components and mechanisms of synaptic plasticity. Our discussion illustrates how local clocks may pervasively modulate neuronal plastic capacity, a phenomenon that we designate here as circadian metaplasticity. We suggest that this function of local clocks supports the temporal optimization of memory processes, illuminating the potential for circadian therapeutic strategies in the prevention and treatment of memory impairment.
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Affiliation(s)
- Matthew J Hartsock
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
| | - Robert L Spencer
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, Colorado 80309, United States.
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32
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Coupling Neuropeptide Levels to Structural Plasticity in Drosophila Clock Neurons. Curr Biol 2020; 30:3154-3166.e4. [PMID: 32619484 DOI: 10.1016/j.cub.2020.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/05/2020] [Accepted: 06/02/2020] [Indexed: 12/24/2022]
Abstract
We have previously reported that pigment dispersing factor (PDF) neurons, which are essential in the control of rest-activity cycles in Drosophila, undergo circadian remodeling of their axonal projections, a phenomenon called circadian structural plasticity. Axonal arborizations display higher complexity during the day and become simpler at night, and this remodeling involves changes in the degree of connectivity. This phenomenon depends on the clock present within the ventrolateral neurons (LNvs) as well as in glia. In this work, we characterize in detail the contribution of the PDF neuropeptide to structural plasticity at different times across the day. Using diverse genetic strategies to temporally restrict its downregulation, we demonstrate that even subtle alterations to PDF cycling at the dorsal protocerebrum correlate with impaired remodeling, underscoring its relevance for the characteristic morning spread; PDF released from the small LNvs (sLNvs) and the large LNvs (lLNvs) contribute to the process. Moreover, forced depolarization recruits activity-dependent mechanisms to mediate growth only at night, overcoming the restriction imposed by the clock on membrane excitability. Interestingly, the active process of terminal remodeling requires PDF receptor (PDFR) signaling acting locally through the cyclic-nucleotide-gated channel ion channel subunit A (CNGA). Thus, clock-dependent PDF signaling shapes the connectivity of these essential clock neurons on daily basis.
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Fernandez MP, Pettibone HL, Bogart JT, Roell CJ, Davey CE, Pranevicius A, Huynh KV, Lennox SM, Kostadinov BS, Shafer OT. Sites of Circadian Clock Neuron Plasticity Mediate Sensory Integration and Entrainment. Curr Biol 2020; 30:2225-2237.e5. [PMID: 32386535 DOI: 10.1016/j.cub.2020.04.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 03/09/2020] [Accepted: 04/09/2020] [Indexed: 01/22/2023]
Abstract
Networks of circadian timekeeping in the brain display marked daily changes in neuronal morphology. In Drosophila melanogaster, the striking daily structural remodeling of the dorsal medial termini of the small ventral lateral neurons has long been hypothesized to mediate endogenous circadian timekeeping. To test this model, we have specifically abrogated these sites of daily neuronal remodeling through the reprogramming of neural development and assessed the effects on circadian timekeeping and clock outputs. Remarkably, the loss of these sites has no measurable effects on endogenous circadian timekeeping or on any of the major output functions of the small ventral lateral neurons. Rather, their loss reduces sites of glutamatergic sensory neurotransmission that normally encodes naturalistic time cues from the environment. These results support an alternative model: structural plasticity in critical clock neurons is the basis for proper integration of light and temperature and gates sensory inputs into circadian clock neuron networks.
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Affiliation(s)
- Maria P Fernandez
- Advanced Science Research Center, The Graduate Center, City University of New York, New York City, NY 10031, USA; Department of Neuroscience and Behavior, Barnard College of Columbia University, New York City, NY 10027, USA.
| | - Hannah L Pettibone
- Advanced Science Research Center, The Graduate Center, City University of New York, New York City, NY 10031, USA; Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Joseph T Bogart
- Advanced Science Research Center, The Graduate Center, City University of New York, New York City, NY 10031, USA
| | - Casey J Roell
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Charles E Davey
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ausra Pranevicius
- Department of Neuroscience and Behavior, Barnard College of Columbia University, New York City, NY 10027, USA
| | - Khang V Huynh
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sara M Lennox
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Boyan S Kostadinov
- Mathematics Department, NYC College of Technology, City University of New York, Brooklyn, NY 11201, USA
| | - Orie T Shafer
- Advanced Science Research Center, The Graduate Center, City University of New York, New York City, NY 10031, USA; Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
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34
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King AN, Sehgal A. Molecular and circuit mechanisms mediating circadian clock output in the Drosophila brain. Eur J Neurosci 2020; 51:268-281. [PMID: 30059181 PMCID: PMC6353709 DOI: 10.1111/ejn.14092] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/12/2018] [Accepted: 07/23/2018] [Indexed: 01/06/2023]
Abstract
A central question in the circadian biology field concerns the mechanisms that translate ~24-hr oscillations of the molecular clock into overt rhythms. Drosophila melanogaster is a powerful system that provided the first understanding of how molecular clocks are generated and is now illuminating the neural basis of circadian behavior. The identity of ~150 clock neurons in the Drosophila brain and their roles in shaping circadian rhythms of locomotor activity have been described before. This review summarizes mechanisms that transmit time-of-day signals from the clock, within the clock network as well as downstream of it. We also discuss the identification of functional multisynaptic circuits between clock neurons and output neurons that regulate locomotor activity.
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Affiliation(s)
- Anna N. King
- Howard Hughes Medical Institute, Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States
| | - Amita Sehgal
- Howard Hughes Medical Institute, Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States
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35
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Arnes M, Alaniz ME, Karam CS, Cho JD, Lopez G, Javitch JA, Santa-Maria I. Role of Tau Protein in Remodeling of Circadian Neuronal Circuits and Sleep. Front Aging Neurosci 2019; 11:320. [PMID: 31824299 PMCID: PMC6881280 DOI: 10.3389/fnagi.2019.00320] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/04/2019] [Indexed: 01/08/2023] Open
Abstract
Multiple neurological, physiological, and behavioral functions are synchronized by circadian clocks into daily rhythms. Neurodegenerative diseases such as Alzheimer's disease and related tauopathies are associated with a decay of circadian rhythms, disruption of sleep patterns, and impaired cognitive function but the mechanisms underlying these alterations are still unclear. Traditional approaches in neurodegeneration research have focused on understanding how pathology impinges on circadian function. Since in Alzheimer's disease and related tauopathies tau proteostasis is compromised, here we sought to understand the role of tau protein in neuronal circadian biology and related behavior. Considering molecular mechanisms underlying circadian rhythms are conserved from Drosophila to humans, here we took advantage of a recently developed tau-deficient Drosophila line to show that loss of tau promotes dysregulation of daily circadian rhythms and sleep patterns. Strikingly, tau deficiency dysregulates the structural plasticity of the small ventral lateral circadian pacemaker neurons by disrupting the temporal cytoskeletal remodeling of its dorsal axonal projections and by inducing a slight increase in the cytoplasmic accumulation of core clock proteins. Taken together, these results suggest that loss of tau function participates in the regulation of circadian rhythms by modulating the correct operation and connectivity of core circadian networks and related behavior.
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Affiliation(s)
- Mercedes Arnes
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, United States
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
| | - Maria E. Alaniz
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, United States
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
| | - Caline S. Karam
- Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Joshua D. Cho
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, United States
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
| | - Gonzalo Lopez
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Jonathan A. Javitch
- Department of Psychiatry, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
- Department of Pharmacology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Ismael Santa-Maria
- Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University, New York, NY, United States
- Department of Pathology and Cell Biology, Columbia University, New York, NY, United States
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Nian X, Chen W, Bai W, Zhao Z, Zhang Y. miR-263b Controls Circadian Behavior and the Structural Plasticity of Pacemaker Neurons by Regulating the LIM-Only Protein Beadex. Cells 2019; 8:cells8080923. [PMID: 31426557 PMCID: PMC6721658 DOI: 10.3390/cells8080923] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 08/09/2019] [Accepted: 08/14/2019] [Indexed: 12/16/2022] Open
Abstract
: Circadian clocks drive rhythmic physiology and behavior to allow adaption to daily environmental changes. In Drosophila, the small ventral lateral neurons (sLNvs) are primary pacemakers that control circadian rhythms. Circadian changes are observed in the dorsal axonal projections of the sLNvs, but their physiological importance and the underlying mechanism are unclear. Here, we identified miR-263b as an important regulator of circadian rhythms and structural plasticity of sLNvs in Drosophila. Depletion of miR-263b (miR-263bKO) in flies dramatically impaired locomotor rhythms under constant darkness. Indeed, miR-263b is required for the structural plasticity of sLNvs. miR-263b regulates circadian rhythms through inhibition of expression of the LIM-only protein Beadex (Bx). Consistently, overexpression of Bx or loss-of-function mutation (BxhdpR26) phenocopied miR-263bKO and miR-263b overexpression in behavior and molecular characteristics. In addition, mutating the miR-263b binding sites in the Bx 3' UTR using CRISPR/Cas9 recapitulated the circadian phenotypes of miR-263bKO flies. Together, these results establish miR-263b as an important regulator of circadian locomotor behavior and structural plasticity.
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Affiliation(s)
- Xiaoge Nian
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
- Department of Biology, University of Nevada Reno, Reno, NV 89557, USA
| | - Wenfeng Chen
- Department of Biology, University of Nevada Reno, Reno, NV 89557, USA
- Institute of Life Sciences, Fuzhou University, Fuzhou 350108, China
| | - Weiwei Bai
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Zhangwu Zhao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Yong Zhang
- Department of Biology, University of Nevada Reno, Reno, NV 89557, USA.
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Niu Y, Liu Z, Nian X, Xu X, Zhang Y. miR-210 controls the evening phase of circadian locomotor rhythms through repression of Fasciclin 2. PLoS Genet 2019; 15:e1007655. [PMID: 31356596 PMCID: PMC6687186 DOI: 10.1371/journal.pgen.1007655] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 08/08/2019] [Accepted: 07/08/2019] [Indexed: 11/19/2022] Open
Abstract
Circadian clocks control the timing of animal behavioral and physiological rhythms. Fruit flies anticipate daily environmental changes and exhibit two peaks of locomotor activity around dawn and dusk. microRNAs are small non-coding RNAs that play important roles in post-transcriptional regulation. Here we identify Drosophila miR-210 as a critical regulator of circadian rhythms. Under light-dark conditions, flies lacking miR-210 (miR-210KO) exhibit a dramatic 2 hrs phase advance of evening anticipatory behavior. However, circadian rhythms and molecular pacemaker function are intact in miR-210KO flies under constant darkness. Furthermore, we identify that miR-210 determines the evening phase of activity through repression of the cell adhesion molecule Fasciclin 2 (Fas2). Ablation of the miR-210 binding site within the 3' UTR of Fas2 (Fas2ΔmiR-210) by CRISPR-Cas9 advances the evening phase as in miR-210KO. Indeed, miR-210 genetically interacts with Fas2. Moreover, Fas2 abundance is significantly increased in the optic lobe of miR-210KO. In addition, overexpression of Fas2 in the miR-210 expressing cells recapitulates the phase advance behavior phenotype of miR-210KO. Together, these results reveal a novel mechanism by which miR-210 regulates circadian locomotor behavior.
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Affiliation(s)
- Ye Niu
- Department of Biology, University of Nevada Reno, Reno, NV, United States of America
| | - Zhenxing Liu
- Department of Biology, University of Nevada Reno, Reno, NV, United States of America
| | - Xiaoge Nian
- Department of Biology, University of Nevada Reno, Reno, NV, United States of America
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Xuehan Xu
- Department of Biology, University of Nevada Reno, Reno, NV, United States of America
| | - Yong Zhang
- Department of Biology, University of Nevada Reno, Reno, NV, United States of America
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38
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Mansilla A, Jordán-Álvarez S, Santana E, Jarabo P, Casas-Tintó S, Ferrús A. Molecular mechanisms that change synapse number. J Neurogenet 2018; 32:155-170. [DOI: 10.1080/01677063.2018.1506781] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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39
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Ma TJ, Zhang ZW, Lu YL, Zhang YY, Tao DC, Liu YQ, Ma YX. CLOCK and BMAL1 stabilize and activate RHOA to promote F-actin formation in cancer cells. Exp Mol Med 2018; 50:1-15. [PMID: 30287810 PMCID: PMC6172197 DOI: 10.1038/s12276-018-0156-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 06/20/2018] [Accepted: 06/22/2018] [Indexed: 02/05/2023] Open
Abstract
Circadian genes control most of the physiological functions in cancer cells, including cell proliferation, migration, and invasion. The CLOCK and BMAL1 complex plays a central role in circadian rhythms. Previous studies have shown that circadian genes may act as oncogenes or tumor-suppressor genes. In addition, F-actin, regulated by RHOA, has been shown to participate in tumor progression. However, the roles of the CLOCK and BMAL1 genes in the regulation of tumor progression via the RHOA-ROCK-CFL pathway remain largely unclear. Here we first indicate that the rearrangement of F-actin is regulated by CLOCK and BMAL1. We found that CLOCK and BMAL1 can upregulate RHOA expression by inhibiting CUL3-mediated ubiquitination and activate RHOA by reducing the interaction between RHOA and RhoGDI. Consequently, CLOCK and BMAL1 control the expression of the components of the RHOA-ROCK-CFL pathway, which alters the dynamics of F-actin/G-actin turnover and promotes cancer cell proliferation, migration, and invasion. In conclusion, our research proposes a novel insight into the role of CLOCK and BMAL1 in tumor cells.
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Affiliation(s)
- Teng-Jiao Ma
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Zhi-Wei Zhang
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yi-Lu Lu
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Ying-Ying Zhang
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Da-Chang Tao
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yun-Qiang Liu
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China
| | - Yong-Xin Ma
- Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital and Collaborative Innovation Center, Sichuan University, 610041, Chengdu, China.
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40
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Azeez IA, Del Gallo F, Cristino L, Bentivoglio M. Daily Fluctuation of Orexin Neuron Activity and Wiring: The Challenge of "Chronoconnectivity". Front Pharmacol 2018; 9:1061. [PMID: 30319410 PMCID: PMC6167434 DOI: 10.3389/fphar.2018.01061] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 09/03/2018] [Indexed: 12/12/2022] Open
Abstract
In the heterogeneous hub represented by the lateral hypothalamus, neurons containing the orexin/hypocretin peptides play a key role in vigilance state transitions and wakefulness stability, energy homeostasis, and other functions relevant for motivated behaviors. Orexin neurons, which project widely to the neuraxis, are innervated by multiple extra- and intra-hypothalamic sources. A key property of the adaptive capacity of orexin neurons is represented by daily variations of activity, which is highest in the period of the animal’s activity and wakefulness. These sets of data are here reviewed. They concern the discharge profile during the sleep/wake cycle, spontaneous Fos induction, peptide synthesis and release reflected by immunostaining intensity and peptide levels in the cerebrospinal fluid as well as postsynaptic effects. At the synaptic level, adaptive capacity of orexin neurons subserved by remodeling of excitatory and inhibitory inputs has been shown in response to changes in the nutritional status and prolonged wakefulness. The present review wishes to highlight that synaptic plasticity in the wiring of orexin neurons also occurs in unperturbed conditions and could account for diurnal variations of orexin neuron activity. Data in zebrafish larvae have shown rhythmic changes in the density of inhibitory innervation of orexin dendrites in relation to vigilance states. Recent findings in mice have indicated a diurnal reorganization of the excitatory/inhibitory balance in the perisomatic innervation of orexin neurons. Taken together these sets of data point to “chronoconnectivity,” i.e., a synaptic rearrangement of inputs to orexin neurons over the course of the day in relation to sleep and wake states. This opens questions on the underlying circadian and homeostatic regulation and on the involved players at synaptic level, which could implicate dual transmitters, cytoskeletal rearrangements, hormonal regulation, as well as surrounding glial cells and extracellular matrix. Furthermore, the question arises of a “chronoconnectivity” in the wiring of other neuronal cell groups of the sleep-wake-regulatory network, many of which are characterized by variations of their firing rate during vigilance states.
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Affiliation(s)
- Idris A Azeez
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Federico Del Gallo
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | | | - Marina Bentivoglio
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.,National Institute of Neuroscience, Verona Unit, Verona, Italy
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41
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Fujiwara Y, Hermann-Luibl C, Katsura M, Sekiguchi M, Ida T, Helfrich-Förster C, Yoshii T. The CCHamide1 Neuropeptide Expressed in the Anterior Dorsal Neuron 1 Conveys a Circadian Signal to the Ventral Lateral Neurons in Drosophila melanogaster. Front Physiol 2018; 9:1276. [PMID: 30246807 PMCID: PMC6139358 DOI: 10.3389/fphys.2018.01276] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 08/22/2018] [Indexed: 12/01/2022] Open
Abstract
The fruit fly Drosophila melanogaster possesses approximately 150 brain clock neurons that control circadian behavioral rhythms. Even though individual clock neurons have self-sustaining oscillators, they interact and synchronize with each other through a network. However, little is known regarding the factors responsible for these network interactions. In this study, we investigated the role of CCHamide1 (CCHa1), a neuropeptide expressed in the anterior dorsal neuron 1 (DN1a), in intercellular communication of the clock neurons. We observed that CCHa1 connects the DN1a clock neurons to the ventral lateral clock neurons (LNv) via the CCHa1 receptor, which is a homolog of the gastrin-releasing peptide receptor playing a role in circadian intercellular communications in mammals. CCHa1 knockout or knockdown flies have a generally low activity level with a special reduction of morning activity. In addition, they exhibit advanced morning activity under light-dark cycles and delayed activity under constant dark conditions, which correlates with an advance/delay of PAR domain Protein 1 (PDP1) oscillations in the small-LNv (s-LNv) neurons that control morning activity. The terminals of the s-LNv neurons show rather high levels of Pigment-dispersing factor (PDF) in the evening, when PDF is low in control flies, suggesting that the knockdown of CCHa1 leads to increased PDF release; PDF signals the other clock neurons and evidently increases the amplitude of their PDP1 cycling. A previous study showed that high-amplitude PDP1 cycling increases the siesta of the flies, and indeed, CCHa1 knockout or knockdown flies exhibit a longer siesta than control flies. The DN1a neurons are known to be receptive to PDF signaling from the s-LNv neurons; thus, our results suggest that the DN1a and s-LNv clock neurons are reciprocally coupled via the neuropeptides CCHa1 and PDF, and this interaction fine-tunes the timing of activity and sleep.
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Affiliation(s)
- Yuri Fujiwara
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | - Christiane Hermann-Luibl
- Department of Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, Germany
| | - Maki Katsura
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan
| | | | - Takanori Ida
- Division of Searching and Identification of Bioactive Peptides, Department of Bioactive Peptides, Frontier Science Research Center, University of Miyazaki, Miyazaki, Japan
- Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan
| | - Charlotte Helfrich-Förster
- Department of 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
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42
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Sheng C, Javed U, Gibbs M, Long C, Yin J, Qin B, Yuan Q. Experience-dependent structural plasticity targets dynamic filopodia in regulating dendrite maturation and synaptogenesis. Nat Commun 2018; 9:3362. [PMID: 30135566 PMCID: PMC6105721 DOI: 10.1038/s41467-018-05871-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 07/27/2018] [Indexed: 11/21/2022] Open
Abstract
Highly motile dendritic protrusions are hallmarks of developing neurons. These exploratory filopodia sample the environment and initiate contacts with potential synaptic partners. To understand the role for dynamic filopodia in dendrite morphogenesis and experience-dependent structural plasticity, we analyzed dendrite dynamics, synapse formation, and dendrite volume expansion in developing ventral lateral neurons (LNvs) of the Drosophila larval visual circuit. Our findings reveal the temporal coordination between heightened dendrite dynamics with synaptogenesis in LNvs and illustrate the strong influence imposed by sensory experience on the prevalence of dendritic filopodia, which regulate the formation of synapses and the expansion of dendritic arbors. Using genetic analyses, we further identified Amphiphysin (Amph), a BAR (Bin/Amphiphysin/Rvs) domain-containing protein as a required component for tuning the dynamic state of LNv dendrites and promoting dendrite maturation. Taken together, our study establishes dynamic filopodia as the key cellular target for experience-dependent regulation of dendrite development. During development, dendrites display structural plasticity, as reflected in the appearance of long, thin and highly motile dendritic filopodia. Here, the authors examine dendritic dynamics of ventral lateral neurons in the developing Drosophila larva, and identify Amphiphysin as an important regulator of this process.
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Affiliation(s)
- Chengyu Sheng
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Uzma Javed
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Mary Gibbs
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Caixia Long
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jun Yin
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Bo Qin
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Quan Yuan
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
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43
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Chatterjee A, Lamaze A, De J, Mena W, Chélot E, Martin B, Hardin P, Kadener S, Emery P, Rouyer F. Reconfiguration of a Multi-oscillator Network by Light in the Drosophila Circadian Clock. Curr Biol 2018; 28:2007-2017.e4. [PMID: 29910074 PMCID: PMC6039274 DOI: 10.1016/j.cub.2018.04.064] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/28/2018] [Accepted: 04/18/2018] [Indexed: 01/02/2023]
Abstract
The brain clock that drives circadian rhythms of locomotor activity relies on a multi-oscillator neuronal network. In addition to synchronizing the clock with day-night cycles, light also reformats the clock-driven daily activity pattern. How changes in lighting conditions modify the contribution of the different oscillators to remodel the daily activity pattern remains largely unknown. Our data in Drosophila indicate that light readjusts the interactions between oscillators through two different modes. We show that a morning s-LNv > DN1p circuit works in series, whereas two parallel evening circuits are contributed by LNds and other DN1ps. Based on the photic context, the master pacemaker in the s-LNv neurons swaps its enslaved partner-oscillator-LNd in the presence of light or DN1p in the absence of light-to always link up with the most influential phase-determining oscillator. When exposure to light further increases, the light-activated LNd pacemaker becomes independent by decoupling from the s-LNvs. The calibration of coupling by light is layered on a clock-independent network interaction wherein light upregulates the expression of the PDF neuropeptide in the s-LNvs, which inhibits the behavioral output of the DN1p evening oscillator. Thus, light modifies inter-oscillator coupling and clock-independent output-gating to achieve flexibility in the network. It is likely that the light-induced changes in the Drosophila brain circadian network could reveal general principles of adapting to varying environmental cues in any neuronal multi-oscillator system.
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Affiliation(s)
- Abhishek Chatterjee
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Angélique Lamaze
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Joydeep De
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Wilson Mena
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Elisabeth Chélot
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Béatrice Martin
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Paul Hardin
- Department of Biology and Center for Biological Clocks Research, Texas A&M University, College Station, TX 77845-3258, USA
| | | | - Patrick Emery
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - François Rouyer
- Institut des Neurosciences Paris-Saclay, Univ. Paris Sud, CNRS, Université Paris-Saclay, 91190 Gif-sur-Yvette, France.
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44
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Hoyle NP, Seinkmane E, Putker M, Feeney KA, Krogager TP, Chesham JE, Bray LK, Thomas JM, Dunn K, Blaikley J, O'Neill JS. Circadian actin dynamics drive rhythmic fibroblast mobilization during wound healing. Sci Transl Med 2018; 9:9/415/eaal2774. [PMID: 29118260 DOI: 10.1126/scitranslmed.aal2774] [Citation(s) in RCA: 120] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 05/25/2017] [Accepted: 10/03/2017] [Indexed: 12/22/2022]
Abstract
Fibroblasts are primary cellular protagonists of wound healing. They also exhibit circadian timekeeping, which imparts an approximately 24-hour rhythm to their biological function. We interrogated the functional consequences of the cell-autonomous clockwork in fibroblasts using a proteome-wide screen for rhythmically expressed proteins. We observed temporal coordination of actin regulators that drives cell-intrinsic rhythms in actin dynamics. In consequence, the cellular clock modulates the efficiency of actin-dependent processes such as cell migration and adhesion, which ultimately affect the efficacy of wound healing. Accordingly, skin wounds incurred during a mouse's active phase exhibited increased fibroblast invasion in vivo and ex vivo, as well as in cultured fibroblasts and keratinocytes. Our experimental results correlate with the observation that the time of injury significantly affects healing after burns in humans, with daytime wounds healing ~60% faster than nighttime wounds. We suggest that circadian regulation of the cytoskeleton influences wound-healing efficacy from the cellular to the organismal scale.
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Affiliation(s)
- Nathaniel P Hoyle
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
| | - Estere Seinkmane
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Marrit Putker
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Kevin A Feeney
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Toke P Krogager
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Johanna E Chesham
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Liam K Bray
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Justyn M Thomas
- Addenbrookes Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QH, UK
| | - Ken Dunn
- University Hospital South Manchester and Honorary, Centre for Health Informatics, Institute of Population Health, University of Manchester, Manchester M23 9LT, UK
| | - John Blaikley
- Centre for Respiratory Medicine and Allergy, University of Manchester and University Hospital of South Manchester NHS Foundation Trust, Manchester M23 9LT, UK
| | - John S O'Neill
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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45
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Wang Q, Abruzzi KC, Rosbash M, Rio DC. Striking circadian neuron diversity and cycling of Drosophila alternative splicing. eLife 2018; 7:35618. [PMID: 29863472 PMCID: PMC6025963 DOI: 10.7554/elife.35618] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/31/2018] [Indexed: 11/13/2022] Open
Abstract
Although alternative pre-mRNA splicing (AS) significantly diversifies the neuronal proteome, the extent of AS is still unknown due in part to the large number of diverse cell types in the brain. To address this complexity issue, we used an annotation-free computational method to analyze and compare the AS profiles between small specific groups of Drosophila circadian neurons. The method, the Junction Usage Model (JUM), allows the comprehensive profiling of both known and novel AS events from specific RNA-seq libraries. The results show that many diverse and novel pre-mRNA isoforms are preferentially expressed in one class of clock neuron and also absent from the more standard Drosophila head RNA preparation. These AS events are enriched in potassium channels important for neuronal firing, and there are also cycling isoforms with no detectable underlying transcriptional oscillations. The results suggest massive AS regulation in the brain that is also likely important for circadian regulation.
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Affiliation(s)
- Qingqing Wang
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,Center for RNA Systems Biology (CRSB), University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States
| | - Katharine C Abruzzi
- Department of Biology, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.,National Center for Behavior Genomics, Brandeis University, Waltham, United States
| | - Michael Rosbash
- Department of Biology, Howard Hughes Medical Institute, Brandeis University, Waltham, United States.,National Center for Behavior Genomics, Brandeis University, Waltham, United States
| | - Donald C Rio
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States.,Center for RNA Systems Biology (CRSB), University of California, Berkeley, Berkeley, United States.,California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, Berkeley, United States
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46
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Krzeptowski W, Hess G, Pyza E. Circadian Plasticity in the Brain of Insects and Rodents. Front Neural Circuits 2018; 12:32. [PMID: 29770112 PMCID: PMC5942159 DOI: 10.3389/fncir.2018.00032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 04/09/2018] [Indexed: 12/22/2022] Open
Abstract
In both vertebrate and invertebrate brains, neurons, glial cells and synapses are plastic, which means that the physiology and structure of these components are modified in response to internal and external stimuli during development and in mature brains. The term plasticity has been introduced in the last century to describe experience-dependent changes in synapse strength and number. These changes result from local functional and morphological synapse modifications; however, these modifications also occur more commonly in pre- and postsynaptic neurons. As a result, neuron morphology and neuronal networks are constantly modified during the life of animals and humans in response to different stimuli. Nevertheless, it has been discovered in flies and mammals that the number of synapses and size and shape of neurons also oscillate during the day. In most cases, these rhythms are circadian since they are generated by endogenous circadian clocks; however, some rhythmic changes in neuron morphology and synapse number and structure are controlled directly by environmental cues or by both external cues and circadian clocks. When the circadian clock is involved in generating cyclic changes in the nervous system, this type of plasticity is called circadian plasticity. It seems to be important in processing sensory information, in learning and in memory. Disruption of the clock may affect major brain functions.
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Affiliation(s)
- Wojciech Krzeptowski
- Department of Cell Biology and Imaging, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
| | - Grzegorz Hess
- Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland.,Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Elżbieta Pyza
- Department of Cell Biology and Imaging, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
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47
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Mendoza-Viveros L, Obrietan K, Cheng HYM. Commentary: miR-132/212 Modulates Seasonal Adaptation and Dendritic Morphology of the Central Circadian Clock. JOURNAL OF NEUROLOGY & NEUROMEDICINE 2018; 3:21-25. [PMID: 29682634 PMCID: PMC5906796 DOI: 10.29245/2572.942x/2017/1.1169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Daily rhythms in behavior and physiology are coordinated by an endogenous clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. This central pacemaker also relays day length information to allow for seasonal adaptation, a process for which melatonin signaling is essential. How the SCN encodes day length is not fully understood. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression by directing target mRNAs for degradation or translational repression. The miR-132/212 cluster plays a key role in facilitating neuronal plasticity, and miR-132 has been shown previously to modulate resetting of the central clock. A recent study from our group showed that miR-132/212 in mice is required for optimal adaptation to seasons and non-24-hour light/dark cycles through regulation of its target gene, methyl CpG-binding protein (MeCP2), in the SCN and dendritic spine density of SCN neurons. Furthermore, in the seasonal rodent Mesocricetus auratus (Syrian hamster), adaptation to short photoperiods is accompanied by structural plasticity in the SCN independently of melatonin signaling, thus further supporting a key role for SCN structural and, in turn, functional plasticity in the coding of day length. In this commentary, we discuss our recent findings in context of what is known about day length encoding by the SCN, and propose future directions.
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Affiliation(s)
- Lucia Mendoza-Viveros
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G3, Canada
| | - Karl Obrietan
- Department of Neuroscience, Ohio State University, Columbus, OH, 43210, USA
| | - Hai-Ying M. Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, L5L 1C6, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, M5S 3G3, Canada
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48
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Schubert FK, Hagedorn N, Yoshii T, Helfrich-Förster C, Rieger D. Neuroanatomical details of the lateral neurons of Drosophila melanogaster support their functional role in the circadian system. J Comp Neurol 2018; 526:1209-1231. [PMID: 29424420 PMCID: PMC5873451 DOI: 10.1002/cne.24406] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/30/2018] [Accepted: 01/30/2018] [Indexed: 12/29/2022]
Abstract
Drosophila melanogaster is a long‐standing model organism in the circadian clock research. A major advantage is the relative small number of about 150 neurons, which built the circadian clock in Drosophila. In our recent work, we focused on the neuroanatomical properties of the lateral neurons of the clock network. By applying the multicolor‐labeling technique Flybow we were able to identify the anatomical similarity of the previously described E2 subunit of the evening oscillator of the clock, which is built by the 5th small ventrolateral neuron (5th s‐LNv) and one ITP positive dorsolateral neuron (LNd). These two clock neurons share the same spatial and functional properties. We found both neurons innervating the same brain areas with similar pre‐ and postsynaptic sites in the brain. Here the anatomical findings support their shared function as a main evening oscillator in the clock network like also found in previous studies. A second quite surprising finding addresses the large lateral ventral PDF‐neurons (l‐LNvs). We could show that the four hardly distinguishable l‐LNvs consist of two subgroups with different innervation patterns. While three of the neurons reflect the well‐known branching pattern reproduced by PDF immunohistochemistry, one neuron per brain hemisphere has a distinguished innervation profile and is restricted only to the proximal part of the medulla‐surface. We named this neuron “extra” l‐LNv (l‐LNvx). We suggest the anatomical findings reflect different functional properties of the two l‐LNv subgroups.
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Affiliation(s)
- Frank K Schubert
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, 97074, Germany
| | - Nicolas Hagedorn
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, 97074, Germany
| | - Taishi Yoshii
- Graduate School of Natural Science and Technology, Okayama University, Okayama, 700-8530, Japan
| | - Charlotte Helfrich-Förster
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, 97074, Germany
| | - Dirk Rieger
- Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Würzburg, Würzburg, 97074, Germany
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49
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Ehmann N, Owald D, Kittel RJ. Drosophila active zones: From molecules to behaviour. Neurosci Res 2018; 127:14-24. [DOI: 10.1016/j.neures.2017.11.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 11/30/2017] [Accepted: 11/30/2017] [Indexed: 11/15/2022]
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50
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Selection for long and short sleep duration in Drosophila melanogaster reveals the complex genetic network underlying natural variation in sleep. PLoS Genet 2017; 13:e1007098. [PMID: 29240764 PMCID: PMC5730107 DOI: 10.1371/journal.pgen.1007098] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 11/01/2017] [Indexed: 12/16/2022] Open
Abstract
Why do some individuals need more sleep than others? Forward mutagenesis screens in flies using engineered mutations have established a clear genetic component to sleep duration, revealing mutants that convey very long or short sleep. Whether such extreme long or short sleep could exist in natural populations was unknown. We applied artificial selection for high and low night sleep duration to an outbred population of Drosophila melanogaster for 13 generations. At the end of the selection procedure, night sleep duration diverged by 9.97 hours in the long and short sleeper populations, and 24-hour sleep was reduced to 3.3 hours in the short sleepers. Neither long nor short sleeper lifespan differed appreciably from controls, suggesting little physiological consequences to being an extreme long or short sleeper. Whole genome sequence data from seven generations of selection revealed several hundred thousand changes in allele frequencies at polymorphic loci across the genome. Combining the data from long and short sleeper populations across generations in a logistic regression implicated 126 polymorphisms in 80 candidate genes, and we confirmed three of these genes and a larger genomic region with mutant and chromosomal deficiency tests, respectively. Many of these genes could be connected in a single network based on previously known physical and genetic interactions. Candidate genes have known roles in several classic, highly conserved developmental and signaling pathways—EGFR, Wnt, Hippo, and MAPK. The involvement of highly pleiotropic pathway genes suggests that sleep duration in natural populations can be influenced by a wide variety of biological processes, which may be why the purpose of sleep has been so elusive. One of the biggest mysteries in biology is the need to sleep. Sleep duration has an underlying genetic basis, suggesting that very long and short sleep times could be bred for experimentally. How far can sleep duration be driven up or down? Here we achieved extremely long and short night sleep duration by subjecting a wild-derived population of Drosophila melanogaster to an experimental breeding program. At the end of the breeding program, long sleepers averaged 9.97 hours more nightly sleep than short sleepers. We analyzed whole-genome sequences from seven generations of the experimental breeding to identify allele frequencies that diverged between long and short sleepers, and verified genes and genomic regions with mutation and deficiency testing. These alleles map to classic developmental and signaling pathways, implicating many diverse processes that potentially affect sleep duration.
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