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Godfrey RK, Alsop E, Bjork RT, Chauhan BS, Ruvalcaba HC, Antone J, Gittings LM, Michael AF, Williams C, Hala'ufia G, Blythe AD, Hall M, Sattler R, Van Keuren-Jensen K, Zarnescu DC. Modelling TDP-43 proteinopathy in Drosophila uncovers shared and neuron-specific targets across ALS and FTD relevant circuits. Acta Neuropathol Commun 2023; 11:168. [PMID: 37864255 PMCID: PMC10588218 DOI: 10.1186/s40478-023-01656-0] [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: 08/03/2023] [Accepted: 09/19/2023] [Indexed: 10/22/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) comprise a spectrum of neurodegenerative diseases linked to TDP-43 proteinopathy, which at the cellular level, is characterized by loss of nuclear TDP-43 and accumulation of cytoplasmic TDP-43 inclusions that ultimately cause RNA processing defects including dysregulation of splicing, mRNA transport and translation. Complementing our previous work in motor neurons, here we report a novel model of TDP-43 proteinopathy based on overexpression of TDP-43 in a subset of Drosophila Kenyon cells of the mushroom body (MB), a circuit with structural characteristics reminiscent of vertebrate cortical networks. This model recapitulates several aspects of dementia-relevant pathological features including age-dependent neuronal loss, nuclear depletion and cytoplasmic accumulation of TDP-43, and behavioral deficits in working memory and sleep that occur prior to axonal degeneration. RNA immunoprecipitations identify several candidate mRNA targets of TDP-43 in MBs, some of which are unique to the MB circuit and others that are shared with motor neurons. Among the latter is the glypican Dally-like-protein (Dlp), which exhibits significant TDP-43 associated reduction in expression during aging. Using genetic interactions we show that overexpression of Dlp in MBs mitigates TDP-43 dependent working memory deficits, conistent with Dlp acting as a mediator of TDP-43 toxicity. Substantiating our findings in the fly model, we find that the expression of GPC6 mRNA, a human ortholog of dlp, is specifically altered in neurons exhibiting the molecular signature of TDP-43 pathology in FTD patient brains. These findings suggest that circuit-specific Drosophila models provide a platform for uncovering shared or disease-specific molecular mechanisms and vulnerabilities across the spectrum of TDP-43 proteinopathies.
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Affiliation(s)
- R Keating Godfrey
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA.
- McGuire Center for Lepidoptera and Biodiversity, Florida Museum of Natural History, University of Florida, 3215 Hull Road, Gainesville, FL, 32611, USA.
| | - Eric Alsop
- Translational Genomics Research Institute, 445 N 5th St., Phoenix, AZ, 85004, USA
| | - Reed T Bjork
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Brijesh S Chauhan
- Cellular and Molecular Physiology, Penn State College of Medicine, 500 University Drive Crescent Building C4605, Hershey, PA, 17033, USA
| | - Hillary C Ruvalcaba
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Jerry Antone
- Translational Genomics Research Institute, 445 N 5th St., Phoenix, AZ, 85004, USA
| | - Lauren M Gittings
- Department of Translational Neuroscience, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA
| | - Allison F Michael
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Christi Williams
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Grace Hala'ufia
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Alexander D Blythe
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA
| | - Megan Hall
- Translational Genomics Research Institute, 445 N 5th St., Phoenix, AZ, 85004, USA
| | - Rita Sattler
- Department of Translational Neuroscience, Barrow Neurological Institute, 350 W Thomas Road, Phoenix, AZ, 85013, USA
| | | | - Daniela C Zarnescu
- Department of Molecular and Cellular Biology, Life Sciences South, University of Arizona, 1007 E. Lowell St., Tucson, AZ, 85721, USA.
- Cellular and Molecular Physiology, Penn State College of Medicine, 500 University Drive Crescent Building C4605, Hershey, PA, 17033, USA.
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2
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Flores-Valle A, Seelig JD. A place learning assay for tethered walking Drosophila. J Neurosci Methods 2022; 378:109657. [PMID: 35760146 DOI: 10.1016/j.jneumeth.2022.109657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 06/16/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022]
Abstract
BACKGROUND Drosophila shows a range of visually guided memory and learning behaviors, including place learning. Investigating the dynamics of neural circuits underlying such behaviors requires learning assays in tethered animals, compatible with in vivo imaging experiments. NEW METHOD Here, we introduce an assay for place learning for tethered walking flies. A cylindrical arena is rotated and translated in real time around the fly in concert with the rotational and translational walking activity measured with an air supported ball, resulting in a mechanical virtual reality (VR). RESULTS Navigation together with heat-based operant conditioning allows flies to learn the location of a cool spot with respect to a visual landmark. Flies optimize the time and distance required to find the cool spot over a similar number of trials as observed in assays with freely moving flies. Additionally, a fraction of flies remembers the location of the cool spot also after the conditioning heat is removed. COMPARISON WITH EXISTING METHODS Learning tasks have been implemented in tethered flying as well as walking flies. Mechanically translating and rotating an arena in concert with the fly's walking activity enables navigation in a three dimensional environment. CONCLUSION In the developed mechanical VR flies can learn to remember the location of a cool place within an otherwise hot environment with respect to a visual landmark. Implementing place learning in a tethered walking configuration is a precondition for investigating the underlying circuit dynamics using functional imaging.
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Affiliation(s)
- Andres Flores-Valle
- Max Planck Institute for Neurobiology of Behavior - caesar (MPINB), Bonn, Germany; International Max Planck Research School for Brain and Behavior, Bonn, Germany
| | - Johannes D Seelig
- Max Planck Institute for Neurobiology of Behavior - caesar (MPINB), Bonn, Germany.
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3
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Petruccelli E, Lark A, Mrkvicka JA, Kitamoto T. Significance of DopEcR, a G-protein coupled dopamine/ecdysteroid receptor, in physiological and behavioral response to stressors. J Neurogenet 2020; 34:55-68. [PMID: 31955616 PMCID: PMC7717672 DOI: 10.1080/01677063.2019.1710144] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 12/25/2019] [Indexed: 12/18/2022]
Abstract
Organisms respond to various environmental stressors by modulating physiology and behavior to maintain homeostasis. Steroids and catecholamines are involved in the highly conserved signaling pathways crucial for mounting molecular and cellular events that ensure immediate or long-term survival under stress conditions. The insect dopamine/ecdysteroid receptor (DopEcR) is a dual G-protein coupled receptor for the catecholamine dopamine and the steroid hormone ecdysone. DopEcR acts in a ligand-dependent manner, mediating dopaminergic signaling and unconventional "nongenomic" ecdysteroid actions through various intracellular signaling pathways. This unique feature of DopEcR raises the interesting possibility that DopEcR may serve as an integrative hub for complex molecular cascades activated under stress conditions. Here, we review previously published studies of Drosophila DopEcR in the context of stress response and also present newly discovered DopEcR loss-of-function phenotypes under different stress conditions. These findings provide corroborating evidence that DopEcR plays vital roles in responses to various stressors, including heat, starvation, alcohol, courtship rejection, and repeated neuronal stimulation in Drosophila. We further discuss what is known about DopEcR in other insects and DopEcR orthologs in mammals, implicating their roles in stress responses. Overall, this review highlights the importance of dual GPCRs for catecholamines and steroids in modulating physiology and behavior under stress conditions. Further multidisciplinary studies of Drosophila DopEcR will contribute to our basic understanding of the functional roles and underlying mechanisms of this class of GPCRs.
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Affiliation(s)
- Emily Petruccelli
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, USA
| | - Arianna Lark
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - James A Mrkvicka
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, USA
| | - Toshihiro Kitamoto
- Interdisciplinary Graduate Program in Genetics, University of Iowa, Iowa City, IA, USA
- Department of Anesthesia, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
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4
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Smith BH, Cook CN. Experimental psychology meets behavioral ecology: what laboratory studies of learning polymorphisms mean for learning under natural conditions, and vice versa. J Neurogenet 2020; 34:178-183. [PMID: 32024408 DOI: 10.1080/01677063.2020.1718674] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Behavior genetics, and specifically the study of learning and memory, has benefitted immensely from the development of powerful forward- and reverse-genetic methods for investigating the relationships between genes and behavior. Application of these methods in controlled laboratory settings has led to insights into gene-behavior relationships. In this perspective article, we argue that the field is now poised to make significant inroads into understanding the adaptive value of heritable variation in behavior in natural populations. Studies of natural variation with several species, in particular, are now in a position to complement laboratory studies of mechanisms, and sometimes this work can lead to counterintuitive insights into the mechanism of gene action on behavior. We make this case using a recent example from work with the honey bee, Apis mellifera.
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Affiliation(s)
- Brian H Smith
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Chelsea N Cook
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
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5
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Williams-Simon PA, Ganesan M, King EG. Learning to collaborate: bringing together behavior and quantitative genomics. J Neurogenet 2020; 34:28-35. [PMID: 31920134 DOI: 10.1080/01677063.2019.1710145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The genetic basis of complex trait like learning and memory have been well studied over the decades. Through those groundbreaking findings, we now have a better understanding about some of the genes and pathways that are involved in learning and/or memory. However, few of these findings identified the naturally segregating variants that are influencing learning and/or memory within populations. In this special issue honoring the legacy of Troy Zars, we review some of the traditional approaches that have been used to elucidate the genetic basis of learning and/or memory, specifically in fruit flies. We highlight some of his contributions to the field, and specifically describe his vision to bring together behavior and quantitative genomics with the aim of expanding our knowledge of the genetic basis of both learning and memory. Finally, we present some of our recent work in this area using a multiparental population (MPP) as a case study and describe the potential of this approach to advance our understanding of neurogenetics.
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Affiliation(s)
| | - Mathangi Ganesan
- Division of Biological Sciences, University of Missouri, Columbia, MO, USA
| | - Elizabeth G King
- Division of Biological Sciences, University of Missouri, Columbia, MO, USA
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6
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Abstract
Preference for spatial locations to maximize favorable outcomes and minimize aversive experiences helps animals survive and adapt to the changing environment. Both visual and non-visual cues play a critical role in spatial navigation and memory of a place supports and guides these strategies. Here we present the neural, genetic and behavioral processes involved in place memory formation using Drosophila melanogaster with a focus on non-visual cue based spatial memories. The work presented here highlights the work done by Dr. Troy Zars and his colleagues with an emphasis on role of biogenic amines in learning, cell biological mechanisms of neural systems and behavioral plasticity of place conditioning.
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Affiliation(s)
- Divya Sitaraman
- Department of Psychology, College of Science, California State University-East Bay, Hayward, CA, USA
| | - Holly LaFerriere
- Department of Biology, Bemidji State University, Bemidji, MN, USA
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7
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Werkhoven Z, Rohrsen C, Qin C, Brembs B, de Bivort B. MARGO (Massively Automated Real-time GUI for Object-tracking), a platform for high-throughput ethology. PLoS One 2019; 14:e0224243. [PMID: 31765421 PMCID: PMC6876843 DOI: 10.1371/journal.pone.0224243] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/08/2019] [Indexed: 12/20/2022] Open
Abstract
Fast object tracking in real time allows convenient tracking of very large numbers of animals and closed-loop experiments that control stimuli for many animals in parallel. We developed MARGO, a MATLAB-based, real-time animal tracking suite for custom behavioral experiments. We demonstrated that MARGO can rapidly and accurately track large numbers of animals in parallel over very long timescales, typically when spatially separated such as in multiwell plates. We incorporated control of peripheral hardware, and implemented a flexible software architecture for defining new experimental routines. These features enable closed-loop delivery of stimuli to many individuals simultaneously. We highlight MARGO's ability to coordinate tracking and hardware control with two custom behavioral assays (measuring phototaxis and optomotor response) and one optogenetic operant conditioning assay. There are currently several open source animal trackers. MARGO's strengths are 1) fast and accurate tracking, 2) high throughput, 3) an accessible interface and data output and 4) real-time closed-loop hardware control for for sensory and optogenetic stimuli, all of which are optimized for large-scale experiments.
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Affiliation(s)
- Zach Werkhoven
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
| | - Christian Rohrsen
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Germany
| | - Chuan Qin
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
| | - Björn Brembs
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Germany
| | - Benjamin de Bivort
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
- * E-mail:
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8
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Werkhoven Z, Rohrsen C, Qin C, Brembs B, de Bivort B. MARGO (Massively Automated Real-time GUI for Object-tracking), a platform for high-throughput ethology. PLoS One 2019; 14:e0224243. [PMID: 31765421 DOI: 10.1101/593046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/08/2019] [Indexed: 05/27/2023] Open
Abstract
Fast object tracking in real time allows convenient tracking of very large numbers of animals and closed-loop experiments that control stimuli for many animals in parallel. We developed MARGO, a MATLAB-based, real-time animal tracking suite for custom behavioral experiments. We demonstrated that MARGO can rapidly and accurately track large numbers of animals in parallel over very long timescales, typically when spatially separated such as in multiwell plates. We incorporated control of peripheral hardware, and implemented a flexible software architecture for defining new experimental routines. These features enable closed-loop delivery of stimuli to many individuals simultaneously. We highlight MARGO's ability to coordinate tracking and hardware control with two custom behavioral assays (measuring phototaxis and optomotor response) and one optogenetic operant conditioning assay. There are currently several open source animal trackers. MARGO's strengths are 1) fast and accurate tracking, 2) high throughput, 3) an accessible interface and data output and 4) real-time closed-loop hardware control for for sensory and optogenetic stimuli, all of which are optimized for large-scale experiments.
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Affiliation(s)
- Zach Werkhoven
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
| | - Christian Rohrsen
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Germany
| | - Chuan Qin
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
| | - Björn Brembs
- Institut für Zoologie - Neurogenetik, Universität Regensburg, Regensburg, Germany
| | - Benjamin de Bivort
- Dept. of Organismic and Evolutionary Biology & Center for Brain Science, Harvard University, Cambridge, MA, United States of America
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9
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Williams-Simon PA, Posey C, Mitchell S, Ng'oma E, Mrkvicka JA, Zars T, King EG. Multiple genetic loci affect place learning and memory performance in Drosophila melanogaster. GENES, BRAIN, AND BEHAVIOR 2019; 18:e12581. [PMID: 31095869 PMCID: PMC6718298 DOI: 10.1111/gbb.12581] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 12/25/2022]
Abstract
Learning and memory are critical functions for all animals, giving individuals the ability to respond to changes in their environment. Within populations, individuals vary, however the mechanisms underlying this variation in performance are largely unknown. Thus, it remains to be determined what genetic factors cause an individual to have high learning ability and what factors determine how well an individual will remember what they have learned. To genetically dissect learning and memory performance, we used the Drosophila synthetic population resource (DSPR), a multiparent mapping resource in the model system Drosophila melanogaster, consisting of a large set of recombinant inbred lines (RILs) that naturally vary in these and other traits. Fruit flies can be trained in a "heat box" to learn to remain on one side of a chamber (place learning) and can remember this (place memory) over short timescales. Using this paradigm, we measured place learning and memory for ~49 000 individual flies from over 700 DSPR RILs. We identified 16 different loci across the genome that significantly affect place learning and/or memory performance, with 5 of these loci affecting both traits. To identify transcriptomic differences associated with performance, we performed RNA-Seq on pooled samples of seven high performing and seven low performing RILs for both learning and memory and identified hundreds of genes with differences in expression in the two sets. Integrating our transcriptomic results with the mapping results allowed us to identify nine promising candidate genes, advancing our understanding of the genetic basis underlying natural variation in learning and memory performance.
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Affiliation(s)
| | - Christopher Posey
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
| | - Samuel Mitchell
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
| | - Enoch Ng'oma
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
| | - James A Mrkvicka
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
| | - Troy Zars
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
| | - Elizabeth G King
- Division of Biological Sciences, University of Missouri, Columbia, Missouri
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10
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Abstract
The ellipsoid body, a doughnut-shaped part of the fly brain, is essential for visual working memory. Gaseous second messengers establish a functional ellipsoid body and act as a short-term aid in orientation behavior.
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Affiliation(s)
- Troy Zars
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
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11
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Baggett V, Mishra A, Kehrer AL, Robinson AO, Shaw P, Zars T. Place learning overrides innate behaviors in Drosophila. ACTA ACUST UNITED AC 2018; 25:122-128. [PMID: 29449456 PMCID: PMC5817280 DOI: 10.1101/lm.046136.117] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 12/19/2017] [Indexed: 11/24/2022]
Abstract
Animals in a natural environment confront many sensory cues. Some of these cues bias behavioral decisions independent of experience, and action selection can reveal a stimulus–response (S–R) connection. However, in a changing environment it would be a benefit for an animal to update behavioral action selection based on experience, and learning might modify even strong S–R relationships. How animals use learning to modify S–R relationships is a largely open question. Three sensory stimuli, air, light, and gravity sources were presented to individual Drosophila melanogaster in both naïve and place conditioning situations. Flies were tested for a potential modification of the S–R relationships of anemotaxis, phototaxis, and negative gravitaxis by a contingency that associated place with high temperature. With two stimuli, significant S–R relationships were abandoned when the cue was in conflict with the place learning contingency. The role of the dunce (dnc) cAMP-phosphodiesterase and the rutabaga (rut) adenylyl cyclase were examined in all conditions. Both dnc1 and rut2080 mutant flies failed to display significant S–R relationships with two attractive cues, and have characteristically lower conditioning scores under most conditions. Thus, learning can have profound effects on separate native S–R relationships in multiple contexts, and mutation of the dnc and rut genes reveal complex effects on behavior.
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Affiliation(s)
- Vincent Baggett
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | - Aditi Mishra
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | - Abigail L Kehrer
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | - Abbey O Robinson
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | - Paul Shaw
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Troy Zars
- Division of Biological Sciences, University of Missouri, Columbia, Missouri 65211, USA
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12
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Popova VV, Brechalov AV, Georgieva SG, Kopytova DV. Nonreplicative functions of the origin recognition complex. Nucleus 2018; 9:460-473. [PMID: 30196754 PMCID: PMC6244734 DOI: 10.1080/19491034.2018.1516484] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 08/04/2018] [Accepted: 08/16/2018] [Indexed: 12/14/2022] Open
Abstract
Origin recognition complex (ORC), a heteromeric six-subunit complex, is the central component of the eukaryotic pre-replication complex. Recent data from yeast, frogs, flies and mammals present compelling evidence that ORC and its individual subunits have nonreplicative functions as well. The majority of these functions, such as heterochromatin formation, chromosome condensation, and segregation are dependent on ORC-DNA interactions. Furthermore, ORC is involved in the control of cell division via its participation in centrosome duplication and cytokinesis. Recent findings have also demonstrated a direct interaction between ORC and mRNPs and highlighted an essential role of ORC in mRNA nuclear export. Along with the growth of evolutionary complexity of organisms, ORC complex functions become more elaborate and new functions of the ORC sub-complexes and individual subunits have emerged.
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Affiliation(s)
- Varvara V. Popova
- Department of Transcription Regulation and Chromatin Dynamics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander V. Brechalov
- Department of Transcription Regulation and Chromatin Dynamics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Sofia G. Georgieva
- Department of Transcription Regulation and Chromatin Dynamics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Daria V. Kopytova
- Department of Transcription Regulation and Chromatin Dynamics, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
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LaFerriere H, Zars T. The Drosophila melanogaster tribbles pseudokinase is necessary for proper memory formation. Neurobiol Learn Mem 2017; 144:68-76. [PMID: 28669782 DOI: 10.1016/j.nlm.2017.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/27/2017] [Accepted: 06/28/2017] [Indexed: 12/11/2022]
Abstract
The tribbles (trbl) pseudokinases play important roles in signaling and physiology in multiple contexts, ranging from innate immunity to cancer, suggesting fundamental cellular functions for the trbls' gene products. Despite expression of the trbl pseudokinases in the nervous systems of invertebrate and vertebrate animals, and evidence that they have a function within mouse and human dopamine neurons, there is no clear case for a function of a Trbl protein that influences behavior. Indeed, the first and only evidence for this type of function comes from Drosophila melanogaster, where a mutation of the single trbl gene was identified in a genetic screen for short-term memory mutant flies. The current study tested flies containing multiple trbl mutant alleles and potential transgenic rescue in both operant place memory and classical olfactory memory paradigms. Genetic complementation tests and transgenic rescue of memory phenotypes in both paradigms show that the D. melanogaster trbl pseudokinase is essential for proper memory formation. Expression analysis with a polyclonal antiserum against Trbl shows that the protein is expressed widely in the fly brain, with higher expression in the cellular rind than the neuropil. Rescue of the behavioral phenotype with transgenic expression indicates the trbl function can be localized to a subset of the nervous system. Thus, we provide the first compelling case for the function of a trbl pseudokinase in the regulation of behavior.
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Affiliation(s)
- Holly LaFerriere
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Troy Zars
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.
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