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DePew AT, Bruckner JJ, O'Connor-Giles KM, Mosca TJ. Neuronal LRP4 directs the development, maturation and cytoskeletal organization of Drosophila peripheral synapses. Development 2024; 151:dev202517. [PMID: 38738619 PMCID: PMC11190576 DOI: 10.1242/dev.202517] [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: 11/09/2023] [Accepted: 05/02/2024] [Indexed: 05/14/2024]
Abstract
Synaptic development requires multiple signaling pathways to ensure successful connections. Transmembrane receptors are optimally positioned to connect the synapse and the rest of the neuron, often acting as synaptic organizers to synchronize downstream events. One such organizer, the LDL receptor-related protein LRP4, is a cell surface receptor that has been most well-studied postsynaptically at mammalian neuromuscular junctions. Recent work, however, identified emerging roles, but how LRP4 acts as a presynaptic organizer and the downstream mechanisms of LRP4 are not well understood. Here, we show that LRP4 functions presynaptically at Drosophila neuromuscular synapses, acting in motoneurons to instruct pre- and postsynaptic development. Loss of presynaptic LRP4 results in multiple defects, impairing active zone organization, synapse growth, physiological function, microtubule organization, synaptic ultrastructure and synapse maturation. We further demonstrate that LRP4 promotes most aspects of presynaptic development via a downstream SR-protein kinase, SRPK79D. These data demonstrate a function for presynaptic LRP4 as a peripheral synaptic organizer, highlight a downstream mechanism conserved with its CNS function in Drosophila, and underscore previously unappreciated but important developmental roles for LRP4 in cytoskeletal organization, synapse maturation and active zone organization.
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Affiliation(s)
- Alison T. DePew
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Joseph J. Bruckner
- Cell and Molecular Biology Training Program, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Kate M. O'Connor-Giles
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
- Carney Institute for Brain Science, Brown University, Providence, RI 02912, 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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2
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DePew AT, Bruckner JJ, O’Connor-Giles KM, Mosca TJ. Neuronal LRP4 directs the development, maturation, and cytoskeletal organization of peripheral synapses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.564481. [PMID: 37961323 PMCID: PMC10635100 DOI: 10.1101/2023.11.03.564481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Synapse development requires multiple signaling pathways to accomplish the myriad of steps needed to ensure a successful connection. Transmembrane receptors on the cell surface are optimally positioned to facilitate communication between the synapse and the rest of the neuron and often function as synaptic organizers to synchronize downstream signaling events. One such organizer, the LDL receptor-related protein LRP4, is a cell surface receptor most well-studied postsynaptically at mammalian neuromuscular junctions. Recent work, however, has identified emerging roles for LRP4 as a presynaptic molecule, but how LRP4 acts as a presynaptic organizer, what roles LRP4 plays in organizing presynaptic biology, and the downstream mechanisms of LRP4 are not well understood. Here we show that LRP4 functions presynaptically at Drosophila neuromuscular synapses, acting in motor neurons to instruct multiple aspects of pre- and postsynaptic development. Loss of presynaptic LRP4 results in a range of developmental defects, impairing active zone organization, synapse growth, physiological function, microtubule organization, synaptic ultrastructure, and synapse maturation. We further demonstrate that LRP4 promotes most aspects of presynaptic development via a downstream SR-protein kinase, SRPK79D. SRPK79D overexpression suppresses synaptic defects associated with loss of lrp4. These data demonstrate a function for LRP4 as a peripheral synaptic organizer acting presynaptically, highlight a downstream mechanism conserved with its CNS function, and indicate previously unappreciated roles for LRP4 in cytoskeletal organization, synapse maturation, and active zone organization, underscoring its developmental importance.
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Affiliation(s)
- Alison T. DePew
- Dept. of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107 USA
| | - Joseph J. Bruckner
- Cell and Molecular Biology Training Program, University of Wisconsin-Madison, Madison, WI 53706 USA
| | - Kate M. O’Connor-Giles
- Department of Neuroscience, Brown University, Providence, RI 02912 USA
- Carney Institute for Brain Science, Brown University, Providence, RI 02912, USA
| | - Timothy J. Mosca
- Dept. of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107 USA
- Lead Contact
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3
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Sullivan M, Fernandez-Aranda F, Camacho-Barcia L, Harkin A, Macrì S, Mora-Maltas B, Jiménez-Murcia S, O'Leary A, Ottomana AM, Presta M, Slattery D, Scholtz S, Glennon JC. Insulin and Disorders of Behavioural Flexibility. Neurosci Biobehav Rev 2023; 150:105169. [PMID: 37059405 DOI: 10.1016/j.neubiorev.2023.105169] [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: 12/30/2022] [Revised: 04/03/2023] [Accepted: 04/10/2023] [Indexed: 04/16/2023]
Abstract
Behavioural inflexibility is a symptom of neuropsychiatric and neurodegenerative disorders such as Obsessive-Compulsive Disorder, Autism Spectrum Disorder and Alzheimer's Disease, encompassing the maintenance of a behaviour even when no longer appropriate. Recent evidence suggests that insulin signalling has roles apart from its regulation of peripheral metabolism and mediates behaviourally-relevant central nervous system (CNS) functions including behavioural flexibility. Indeed, insulin resistance is reported to generate anxious, perseverative phenotypes in animal models, with the Type 2 diabetes medication metformin proving to be beneficial for disorders including Alzheimer's Disease. Structural and functional neuroimaging studies of Type 2 diabetes patients have highlighted aberrant connectivity in regions governing salience detection, attention, inhibition and memory. As currently available therapeutic strategies feature high rates of resistance, there is an urgent need to better understand the complex aetiology of behaviour and develop improved therapeutics. In this review, we explore the circuitry underlying behavioural flexibility, changes in Type 2 diabetes, the role of insulin in CNS outcomes and mechanisms of insulin involvement across disorders of behavioural inflexibility.
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Affiliation(s)
- Mairéad Sullivan
- Conway Institute of Biomedical and Biomolecular Research, School of Medicine, University College Dublin, Dublin, Ireland.
| | - Fernando Fernandez-Aranda
- Department of Psychiatry, University Hospital of Bellvitge, Barcelona, Spain; Psychoneurobiology of Eating and Addictive Behaviors Group, Neurosciences Program, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain; CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Barcelona, Spain; Department of Clinical Sciences, School of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain
| | - Lucía Camacho-Barcia
- Department of Psychiatry, University Hospital of Bellvitge, Barcelona, Spain; Psychoneurobiology of Eating and Addictive Behaviors Group, Neurosciences Program, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain; CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Barcelona, Spain
| | - Andrew Harkin
- School of Pharmacy and Pharmaceutical Sciences, Trinity College Dublin, Ireland
| | - Simone Macrì
- Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy
| | - Bernat Mora-Maltas
- Department of Psychiatry, University Hospital of Bellvitge, Barcelona, Spain; Psychoneurobiology of Eating and Addictive Behaviors Group, Neurosciences Program, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
| | - Susana Jiménez-Murcia
- Department of Psychiatry, University Hospital of Bellvitge, Barcelona, Spain; Psychoneurobiology of Eating and Addictive Behaviors Group, Neurosciences Program, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain; CIBER Fisiopatología Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Barcelona, Spain; Department of Clinical Sciences, School of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain
| | - Aet O'Leary
- University Hospital Frankfurt, Frankfurt, Germany
| | - Angela Maria Ottomana
- Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; Neuroscience Unit, Department of Medicine, University of Parma, 43100 Parma, Italy
| | - Martina Presta
- Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, 00161 Rome, Italy; Department of Physiology and Pharmacology, Sapienza University of Rome, 00185 Rome, Italy
| | | | | | - Jeffrey C Glennon
- Conway Institute of Biomedical and Biomolecular Research, School of Medicine, University College Dublin, Dublin, Ireland
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4
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Selle J, Dinger K, Jentgen V, Zanetti D, Will J, Georgomanolis T, Vohlen C, Wilke R, Kojonazarov B, Klymenko O, Mohr J, V Koningsbruggen-Rietschel S, Rhodes CJ, Ulrich A, Hirani D, Nestler T, Odenthal M, Mahabir E, Nayakanti S, Dabral S, Wunderlich T, Priest J, Seeger W, Dötsch J, Pullamsetti SS, Alejandre Alcazar MA. Maternal and perinatal obesity induce bronchial obstruction and pulmonary hypertension via IL-6-FoxO1-axis in later life. Nat Commun 2022; 13:4352. [PMID: 35896539 PMCID: PMC9329333 DOI: 10.1038/s41467-022-31655-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/22/2022] [Indexed: 02/06/2023] Open
Abstract
Obesity is a pre-disposing condition for chronic obstructive pulmonary disease, asthma, and pulmonary arterial hypertension. Accumulating evidence suggests that metabolic influences during development can determine chronic lung diseases (CLD). We demonstrate that maternal obesity causes early metabolic disorder in the offspring. Here, interleukin-6 induced bronchial and microvascular smooth muscle cell (SMC) hyperproliferation and increased airway and pulmonary vascular resistance. The key anti-proliferative transcription factor FoxO1 was inactivated via nuclear exclusion. These findings were confirmed using primary SMC treated with interleukin-6 and pharmacological FoxO1 inhibition as well as genetic FoxO1 ablation and constitutive activation. In vivo, we reproduced the structural and functional alterations in offspring of obese dams via the SMC-specific ablation of FoxO1. The reconstitution of FoxO1 using IL-6-deficient mice and pharmacological treatment did not protect against metabolic disorder but prevented SMC hyperproliferation. In human observational studies, childhood obesity was associated with reduced forced expiratory volume in 1 s/forced vital capacity ratio Z-score (used as proxy for lung function) and asthma. We conclude that the interleukin-6-FoxO1 pathway in SMC is a molecular mechanism by which perinatal obesity programs the bronchial and vascular structure and function, thereby driving CLD development. Thus, FoxO1 reconstitution provides a potential therapeutic option for preventing this metabolic programming of CLD.
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Affiliation(s)
- Jaco Selle
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Katharina Dinger
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Vanessa Jentgen
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Daniela Zanetti
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA
| | - Johannes Will
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Theodoros Georgomanolis
- Faculty of Medicine and University Hospital Cologne, Cologne Center for Genomics (CCG), University of Cologne, Cologne, Germany
| | - Christina Vohlen
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
| | - Rebecca Wilke
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Baktybek Kojonazarov
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
| | - Oleksiy Klymenko
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
| | - Jasmine Mohr
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Silke V Koningsbruggen-Rietschel
- Faculty of Medicine and University Hospital Cologne, Pediatric Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Christopher J Rhodes
- National Heart and Lung Institute, Hammersmith Campus, Imperial College London, London, UK
| | - Anna Ulrich
- National Heart and Lung Institute, Hammersmith Campus, Imperial College London, London, UK
| | - Dharmesh Hirani
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
| | - Tim Nestler
- Faculty of Medicine and University Hospital Cologne, Institute of Pathology, University of Cologne, Cologne, Germany
| | - Margarete Odenthal
- Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Institute of Pathology, University of Cologne, Cologne, Germany
| | - Esther Mahabir
- Faculty of Medicine and University Hospital Cologne, Comparative Medicine, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Sreenath Nayakanti
- Department of Lung Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Swati Dabral
- Department of Lung Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
| | - Thomas Wunderlich
- Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Max-Planck-Institute for Metabolism Research, Cologne, Germany
- Faculty of Medicine and University Hospital Cologne, Cologne Excellence Cluster for Stress Responses in Ageing-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| | - James Priest
- Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Werner Seeger
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
- Department of Lung Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
- Department of Internal Medicine, German Center for Lung Research (DZL), Cardio-Pulmonary Institute (CPI), Justus Liebig University, Giessen, Germany
| | - Jörg Dötsch
- Faculty of Medicine and University Hospital Cologne, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Soni S Pullamsetti
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany
- Department of Lung Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, Member of the German Center for Lung Research (DZL), Bad Nauheim, Germany
- Department of Internal Medicine, German Center for Lung Research (DZL), Cardio-Pulmonary Institute (CPI), Justus Liebig University, Giessen, Germany
| | - Miguel A Alejandre Alcazar
- Faculty of Medicine and University Hospital Cologne, Translational Experimental Pediatrics-Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany.
- Faculty of Medicine and University Hospital Cologne, Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany.
- Institute for Lung Health (ILH), University of Giessen and Marburg Lung Centre (UGMLC), Member of the German Centre for Lung Research (DZL), Gießen, Germany.
- Faculty of Medicine and University Hospital Cologne, Cologne Excellence Cluster for Stress Responses in Ageing-Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
- Department of Internal Medicine, German Center for Lung Research (DZL), Cardio-Pulmonary Institute (CPI), Justus Liebig University, Giessen, Germany.
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5
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Saunders HAJ, Johnson-Schlitz DM, Jenkins BV, Volkert PJ, Yang SZ, Wildonger J. Acetylated α-tubulin K394 regulates microtubule stability to shape the growth of axon terminals. Curr Biol 2022; 32:614-630.e5. [PMID: 35081332 PMCID: PMC8843987 DOI: 10.1016/j.cub.2021.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/19/2021] [Accepted: 12/07/2021] [Indexed: 02/09/2023]
Abstract
Microtubules are essential to neuron shape and function. Acetylation of tubulin has the potential to directly tune the behavior and function of microtubules in cells. Although proteomic studies have identified several acetylation sites in α-tubulin, the effects of acetylation at these sites remains largely unknown. This includes the highly conserved residue lysine 394 (K394), which is located at the αβ-tubulin dimer interface. Using a fly model, we show that α-tubulin K394 is acetylated in the nervous system and is an essential residue. We found that an acetylation-blocking mutation in endogenous α-tubulin, K394R, perturbs the synaptic morphogenesis of motoneurons and reduces microtubule stability. Intriguingly, the K394R mutation has opposite effects on the growth of two functionally and morphologically distinct motoneurons, revealing neuron-type-specific responses when microtubule stability is altered. Eliminating the deacetylase HDAC6 increases K394 acetylation, and the over-expression of HDAC6 reduces microtubule stability similar to the K394R mutant. Thus, our findings implicate α-tubulin K394 and its acetylation in the regulation of microtubule stability and suggest that HDAC6 regulates K394 acetylation during synaptic morphogenesis.
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Affiliation(s)
- Harriet A. J. Saunders
- Integrated Program in Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Dena M. Johnson-Schlitz
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Brian V. Jenkins
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Peter J. Volkert
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Biochemistry Scholars Program, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
| | - Sihui Z. Yang
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Cellular & Molecular Biology Graduate Program, University of Wisconsin-Madison, 1525 Linden Drive, Madison, WI, 53706, USA
| | - Jill Wildonger
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA,Current address: Pediatrics Department and Biological Sciences Division, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA,Lead and author for correspondence:
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6
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Martinez D, Zhu M, Guidry JJ, Majeste N, Mao H, Yanofsky ST, Tian X, Wu C. Mask, the Drosophila ankyrin repeat and KH domain-containing protein, affects microtubule stability. J Cell Sci 2021; 134:272264. [PMID: 34553767 PMCID: PMC8572007 DOI: 10.1242/jcs.258512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 09/16/2021] [Indexed: 11/26/2022] Open
Abstract
Proper regulation of microtubule (MT) stability and dynamics is vital for essential cellular processes, including axonal transportation and synaptic growth and remodeling in neurons. In the present study, we demonstrate that the Drosophila ankyrin repeat and KH domain-containing protein Mask negatively affects MT stability in both larval muscles and motor neurons. In larval muscles, loss-of-function of mask increases MT polymer length, and in motor neurons, loss of mask function results in overexpansion of the presynaptic terminal at the larval neuromuscular junctions (NMJs). mask genetically interacts with stathmin (stai), a neuronal modulator of MT stability, in the regulation of axon transportation and synaptic terminal stability. Our structure–function analysis of Mask revealed that its ankyrin repeats domain-containing N-terminal portion is sufficient to mediate Mask's impact on MT stability. Furthermore, we discovered that Mask negatively regulates the abundance of the MT-associated protein Jupiter in motor neuron axons, and that neuronal knocking down of Jupiter partially suppresses mask loss-of-function phenotypes at the larval NMJs. Taken together, our studies demonstrate that Mask is a novel regulator for MT stability, and such a role of Mask requires normal function of Jupiter. Summary: Mask is a novel regulator of MT stability in Drosophila. Mask shows prominent interplay with two important modulators of MT, Tau and Stathmin (Stai), whose mutations are related to human diseases.
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Affiliation(s)
- Daniel Martinez
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Mingwei Zhu
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Jessie J Guidry
- Proteomics Core Facility, and the Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Niles Majeste
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Hui Mao
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Sarah T Yanofsky
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Xiaolin Tian
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Chunlai Wu
- Neuroscience Center of Excellence, Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
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7
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Bu S, Yong WL, Lim BJW, Kondo S, Yu F. A systematic analysis of microtubule-destabilizing factors during dendrite pruning in Drosophila. EMBO Rep 2021; 22:e52679. [PMID: 34338441 DOI: 10.15252/embr.202152679] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/10/2021] [Accepted: 07/12/2021] [Indexed: 11/09/2022] Open
Abstract
It has long been thought that microtubule disassembly, one of the earliest cellular events, contributes to neuronal pruning and neurodegeneration in development and disease. However, how microtubule disassembly drives neuronal pruning remains poorly understood. Here, we conduct a systematic investigation of various microtubule-destabilizing factors and identify exchange factor for Arf6 (Efa6) and Stathmin (Stai) as new regulators of dendrite pruning in ddaC sensory neurons during Drosophila metamorphosis. We show that Efa6 is both necessary and sufficient to regulate dendrite pruning. Interestingly, Efa6 and Stai facilitate microtubule turnover and disassembly prior to dendrite pruning without compromising the minus-end-out microtubule orientation in dendrites. Moreover, our pharmacological and genetic manipulations strongly support a key role of microtubule disassembly in promoting dendrite pruning. Thus, this systematic study highlights the importance of two selective microtubule destabilizers in dendrite pruning and substantiates a causal link between microtubule disassembly and neuronal pruning.
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Affiliation(s)
- Shufeng Bu
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Wei Lin Yong
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore
| | - Bryan Jian Wei Lim
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Shu Kondo
- Invertebrate Genetics Laboratory, National Institute of Genetics, Shizuoka, Japan
| | - Fengwei Yu
- Temasek Life Sciences Laboratory, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore
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8
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Rana T, Behl T, Sehgal A, Mehta V, Singh S, Sharma N, Bungau S. Elucidating the Possible Role of FoxO in Depression. Neurochem Res 2021; 46:2761-2775. [PMID: 34075521 DOI: 10.1007/s11064-021-03364-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/23/2021] [Accepted: 05/25/2021] [Indexed: 12/21/2022]
Abstract
Forkhead box-O (FoxO) transcriptional factors perform essential functions in several physiological and biological processes. Recent studies have shown that FoxO is implicated in the pathophysiology of depression. Changes in the upstream mediators of FoxOs including brain-derived neurotrophic factor (BDNF) and protein kinase B have been associated with depressive disorder and the antidepressant agents are known to alter the phosphorylation of FoxOs. Moreover, FoxOs might be regulated by serotonin or noradrenaline signaling and the hypothalamic-pituitary-adrenal (HPA)-axis,both of them are associated with the development of the depressive disorder. FoxO also regulates neural morphology, synaptogenesis, and neurogenesis in the hippocampus, which accounts for the pathogenesis of the depressive disorder. The current article underlined the potential functions of FoxOs in the etiology of depressive disorder and formulate few essential proposals for further investigation. The review also proposes that FoxO and its signal pathway might establish possible therapeutic mediators for the management of depressive disorder.
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Affiliation(s)
- Tarapati Rana
- Chitkara College of Pharmacy, Chitkara University, Chandigarh, Punjab, India.,Government Pharmacy College, Seraj, Mandi, Himachal Pradesh, India
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Chandigarh, Punjab, India.
| | - Aayush Sehgal
- Chitkara College of Pharmacy, Chitkara University, Chandigarh, Punjab, India
| | - Vineet Mehta
- Government College of Pharmacy, Rohru, Distt., Shimla, Himachal Pradesh, India
| | - Sukhbir Singh
- Chitkara College of Pharmacy, Chitkara University, Chandigarh, Punjab, India
| | - Neelam Sharma
- Chitkara College of Pharmacy, Chitkara University, Chandigarh, Punjab, India
| | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, Oradea, Romania
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9
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Belalcazar HM, Hendricks EL, Zamurrad S, Liebl FLW, Secombe J. The histone demethylase KDM5 is required for synaptic structure and function at the Drosophila neuromuscular junction. Cell Rep 2021; 34:108753. [PMID: 33596422 PMCID: PMC7945993 DOI: 10.1016/j.celrep.2021.108753] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/14/2020] [Accepted: 01/25/2021] [Indexed: 02/08/2023] Open
Abstract
Mutations in the genes encoding the lysine demethylase 5 (KDM5) family of histone demethylases are observed in individuals with intellectual disability (ID). Despite clear evidence linking KDM5 function to neurodevelopmental pathways, how this family of proteins impacts transcriptional programs to mediate synaptic structure and activity remains unclear. Using the Drosophila larval neuromuscular junction (NMJ), we show that KDM5 is required presynaptically for neuroanatomical development and synaptic function. The Jumonji C (JmjC) domain-encoded histone demethylase activity of KDM5, which is expected to be diminished by many ID-associated alleles, is required for appropriate synaptic morphology and neurotransmission. The activity of the C5HC2 zinc finger is also required, as an ID-associated mutation in this motif reduces NMJ bouton number, increases bouton size, and alters microtubule dynamics. KDM5 therefore uses demethylase-dependent and independent mechanisms to regulate NMJ structure and activity, highlighting the complex nature by which this chromatin modifier carries out its neuronal gene-regulatory programs.
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Affiliation(s)
- Helen M Belalcazar
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Emily L Hendricks
- Department of Biological Sciences, Southern Illinois University Edwardsville, 44 Circle Drive, Edwardsville, IL 62026, USA
| | - Sumaira Zamurrad
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Faith L W Liebl
- Department of Biological Sciences, Southern Illinois University Edwardsville, 44 Circle Drive, Edwardsville, IL 62026, USA
| | - Julie Secombe
- Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1410 Pelham Parkway South, Bronx, NY 10461, USA.
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10
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Birnbaum A, Sodders M, Bouska M, Chang K, Kang P, McNeill E, Bai H. FOXO Regulates Neuromuscular Junction Homeostasis During Drosophila Aging. Front Aging Neurosci 2021; 12:567861. [PMID: 33584240 PMCID: PMC7874159 DOI: 10.3389/fnagi.2020.567861] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 12/04/2020] [Indexed: 12/17/2022] Open
Abstract
The transcription factor foxo is a known regulator of lifespan extension and tissue homeostasis. It has been linked to the maintenance of neuronal processes across many species and has been shown to promote youthful characteristics by regulating cytoskeletal flexibility and synaptic plasticity at the neuromuscular junction (NMJ). However, the role of foxo in aging neuromuscular junction function has yet to be determined. We profiled adult Drosophila foxo- null mutant abdominal ventral longitudinal muscles and found that young mutants exhibited morphological profiles similar to those of aged wild-type flies, such as larger bouton areas and shorter terminal branches. We also observed changes to the axonal cytoskeleton and an accumulation of late endosomes in foxo null mutants and motor neuron-specific foxo knockdown flies, similar to those of aged wild-types. Motor neuron-specific overexpression of foxo can delay age-dependent changes to NMJ morphology, suggesting foxo is responsible for maintaining NMJ integrity during aging. Through genetic screening, we identify several downstream factors mediated through foxo-regulated NMJ homeostasis, including genes involved in the MAPK pathway. Interestingly, the phosphorylation of p38 was increased in the motor neuron-specific foxo knockdown flies, suggesting foxo acts as a suppressor of p38/MAPK activation. Our work reveals that foxo is a key regulator for NMJ homeostasis, and it may maintain NMJ integrity by repressing MAPK signaling.
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Affiliation(s)
- Allison Birnbaum
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States.,Department of Cell, Developmental and Integrative Biology, University of Alabama Birmingham, Birmingham, AL, United States
| | - Maggie Sodders
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States
| | - Mark Bouska
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States
| | - Kai Chang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States
| | - Ping Kang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States
| | - Elizabeth McNeill
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
| | - Hua Bai
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA, United States
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11
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He Q, Du J, Wei L, Zhao Z. AKH-FOXO pathway regulates starvation-induced sleep loss through remodeling of the small ventral lateral neuron dorsal projections. PLoS Genet 2020; 16:e1009181. [PMID: 33104699 PMCID: PMC7644095 DOI: 10.1371/journal.pgen.1009181] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 11/05/2020] [Accepted: 10/08/2020] [Indexed: 11/18/2022] Open
Abstract
Starvation caused by adverse feeding stresses or food shortages has been reported to result in sleep loss in animals. However, how the starvation signal interacts with the central nervous system is still unknown. Here, the adipokinetic hormone (AKH)-Fork head Box-O (FOXO) pathway is shown to respond to energy change and adjust the sleep of Drosophila through remodeling of the s-LNv (small ventral lateral neurons) dorsal projections. Our results show that starvation prevents flies from going to sleep after the first light-dark transition. The LNvs are required for starvation-induced sleep loss through extension of the pigment dispersing factor (PDF)-containing s-LNv dorsal projections. Further studies reveal that loss of AKH or AKHR (akh receptor) function blocks starvation-induced extension of s-LNv dorsal projections and rescues sleep suppression during food deprivation. FOXO, which has been reported to regulate synapse plasticity of neurons, acts as starvation response factor downstream of AKH, and down regulation of FOXO level considerably alleviates the influence of starvation on s-LNv dorsal projections and sleep. Taking together, our results outline the transduction pathways between starvation signal and sleep, and reveal a novel functional site for sleep regulation.
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Affiliation(s)
- Qiankun He
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Juan Du
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
| | - Liya Wei
- College of Life Science, Hebei University, Baoding, China
| | - Zhangwu Zhao
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, China
- * E-mail:
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12
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Castets P, Ham DJ, Rüegg MA. The TOR Pathway at the Neuromuscular Junction: More Than a Metabolic Player? Front Mol Neurosci 2020; 13:162. [PMID: 32982690 PMCID: PMC7485269 DOI: 10.3389/fnmol.2020.00162] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/05/2020] [Indexed: 12/18/2022] Open
Abstract
The neuromuscular junction (NMJ) is the chemical synapse connecting motor neurons and skeletal muscle fibers. NMJs allow all voluntary movements, and ensure vital functions like breathing. Changes in the structure and function of NMJs are hallmarks of numerous pathological conditions that affect muscle function including sarcopenia, the age-related loss of muscle mass and function. However, the molecular mechanisms leading to the morphological and functional perturbations in the pre- and post-synaptic compartments of the NMJ remain poorly understood. Here, we discuss the role of the metabolic pathway associated to the kinase TOR (Target of Rapamycin) in the development, maintenance and alterations of the NMJ. This is of particular interest as the TOR pathway has been implicated in aging, but its role at the NMJ is still ill-defined. We highlight the respective functions of the two TOR-associated complexes, TORC1 and TORC2, and discuss the role of localized protein synthesis and autophagy regulation in motor neuron terminals and sub-synaptic regions of muscle fibers and their possible effects on NMJ maintenance.
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Affiliation(s)
- Perrine Castets
- Department of Cell Physiology and Metabolism, Faculty of Medicine, University of Geneva, Geneva, Switzerland
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13
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Rolls MM, Thyagarajan P, Feng C. Microtubule dynamics in healthy and injured neurons. Dev Neurobiol 2020; 81:321-332. [PMID: 32291942 DOI: 10.1002/dneu.22746] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/22/2020] [Accepted: 04/08/2020] [Indexed: 12/28/2022]
Abstract
Most neurons must last a lifetime and their microtubule cytoskeleton is an important contributor to their longevity. Neurons have some of the most stable microtubules of all cells, but the tip of every microtubule remains dynamic and, although requiring constant GTP consumption, microtubules are always being rebuilt. While some ongoing level of rebuilding always occurs, overall microtubule stability can be modulated in response to injury and stress as well as the normal developmental process of pruning. Specific microtubule severing proteins act in different contexts to increase microtubule dynamicity and promote degeneration and pruning. After axon injury, complex changes in dynamics occur and these are important for both neuroprotection induced by injury and subsequent outgrowth of a new axon. Understanding how microtubule dynamics is modulated in different scenarios, as well as the impact of the changes in stability, is an important avenue to explore for development of strategies to promote neuroprotection and regeneration.
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Affiliation(s)
- Melissa M Rolls
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Pankajam Thyagarajan
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
| | - Chengye Feng
- Biochemistry and Molecular Biology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, USA
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14
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Shi Q, Lin YQ, Saliba A, Xie J, Neely GG, Banerjee S. Tubulin Polymerization Promoting Protein, Ringmaker, and MAP1B Homolog Futsch Coordinate Microtubule Organization and Synaptic Growth. Front Cell Neurosci 2019; 13:192. [PMID: 31156389 PMCID: PMC6529516 DOI: 10.3389/fncel.2019.00192] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 04/16/2019] [Indexed: 12/15/2022] Open
Abstract
Drosophila Ringmaker (Ringer) is homologous to the human Tubulin Polymerization Promoting Proteins (TPPPs) that are implicated in the stabilization and bundling of microtubules (MTs) that are particularly important for neurons and are also implicated in synaptic organization and plasticity. No in vivo functional data exist that have addressed the role of TPPP in synapse organization in any system. Here, we present the phenotypic and functional characterization of ringer mutants during Drosophila larval neuromuscular junction (NMJ) synaptic development. ringer mutants show reduced synaptic growth and transmission and display phenotypic similarities and genetic interactions with the Drosophila homolog of vertebrate Microtubule Associated Protein (MAP)1B, futsch. Immunohistochemical and biochemical analyses show that individual and combined loss of Ringer and Futsch cause a significant reduction in MT loops at the NMJs and reduced acetylated-tubulin levels. Presynaptic over-expression of Ringer and Futsch causes elevated levels of acetylated-tubulin and significant increase in NMJ MT loops. These results indicate that Ringer and Futsch regulate synaptic MT organization in addition to synaptic growth. Together our findings may inform studies on the close mammalian homolog, TPPP, and provide insights into the role of MTs and associated proteins in synapse growth and organization.
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Affiliation(s)
- Qian Shi
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health, San Antonio, TX, United States
| | - Yong Qi Lin
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Afaf Saliba
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health, San Antonio, TX, United States
| | - Jing Xie
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health, San Antonio, TX, United States
- Xiangya School of Medicine, Central South University, Changsha, China
| | - G. Gregory Neely
- The Dr. John and Anne Chong Lab for Functional Genomics, Charles Perkins Centre and School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Swati Banerjee
- Department of Cellular and Integrative Physiology, Long School of Medicine, University of Texas Health, San Antonio, TX, United States
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15
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Politano SF, Salemme RR, Ashley J, López-Rivera JA, Bakula TA, Puhalla KA, Quinn JP, Juszczak MJ, Phillip LK, Carrillo RA, Vanderzalm PJ. Tao Negatively Regulates BMP Signaling During Neuromuscular Junction Development in Drosophila. Dev Neurobiol 2019; 79:335-349. [PMID: 31002474 DOI: 10.1002/dneu.22681] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 03/15/2019] [Accepted: 04/15/2019] [Indexed: 12/15/2022]
Abstract
The coordinated growth and development of synapses is critical for all aspects of neural circuit function and mutations that disrupt these processes can result in various neurological defects. Several anterograde and retrograde signaling pathways, including the canonical Bone Morphogenic Protein (BMP) pathway, regulate synaptic development in vertebrates and invertebrates. At the Drosophila larval neuromuscular junction (NMJ), the retrograde BMP pathway is a part of the machinery that controls NMJ expansion concurrent with larval growth. We sought to determine whether the conserved Hippo pathway, critical for proportional growth in other tissues, also functions in NMJ development. We found that neuronal loss of the serine-threonine protein kinase Tao, a regulator of the Hippo signaling pathway, results in supernumerary boutons which contain a normal density of active zones. Tao is also required for proper synaptic function, as reduction of Tao results in NMJs with decreased evoked excitatory junctional potentials. Surprisingly, Tao function in NMJ growth is independent of the Hippo pathway. Instead, our experiments suggest that Tao negatively regulates BMP signaling as reduction of Tao leads to an increase in pMad levels in motor neuron nuclei and an increase in BMP target gene expression. Taken together, these results support a role for Tao as a novel inhibitor of BMP signaling in motor neurons during synaptic development and function.
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Affiliation(s)
- Stephen F Politano
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - Ryan R Salemme
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - James Ashley
- Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois, 60637
| | | | - Toren A Bakula
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - Kathryn A Puhalla
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - John P Quinn
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - Madison J Juszczak
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - Lauren K Phillip
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
| | - Robert A Carrillo
- Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois, 60637
| | - Pamela J Vanderzalm
- Department of Biology, John Carroll University, University Heights, Ohio, 44118
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16
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Feng C, Thyagarajan P, Shorey M, Seebold DY, Weiner AT, Albertson RM, Rao KS, Sagasti A, Goetschius DJ, Rolls MM. Patronin-mediated minus end growth is required for dendritic microtubule polarity. J Cell Biol 2019; 218:2309-2328. [PMID: 31076454 PMCID: PMC6605808 DOI: 10.1083/jcb.201810155] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 03/13/2019] [Accepted: 04/23/2019] [Indexed: 02/06/2023] Open
Abstract
Feng et al. describe persistent neuronal microtubule minus end growth that depends on the CAMSAP protein Patronin and is needed for dendritic minus-end-out polarity. Microtubule minus ends are thought to be stable in cells. Surprisingly, in Drosophila and zebrafish neurons, we observed persistent minus end growth, with runs lasting over 10 min. In Drosophila, extended minus end growth depended on Patronin, and Patronin reduction disrupted dendritic minus-end-out polarity. In fly dendrites, microtubule nucleation sites localize at dendrite branch points. Therefore, we hypothesized minus end growth might be particularly important beyond branch points. Distal dendrites have mixed polarity, and reduction of Patronin lowered the number of minus-end-out microtubules. More strikingly, extra Patronin made terminal dendrites almost completely minus-end-out, indicating low Patronin normally limits minus-end-out microtubules. To determine whether minus end growth populated new dendrites with microtubules, we analyzed dendrite development and regeneration. Minus ends extended into growing dendrites in the presence of Patronin. In sum, our data suggest that Patronin facilitates sustained microtubule minus end growth, which is critical for populating dendrites with minus-end-out microtubules.
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Affiliation(s)
- Chengye Feng
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Pankajam Thyagarajan
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Matthew Shorey
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Dylan Y Seebold
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Alexis T Weiner
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Richard M Albertson
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Kavitha S Rao
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Alvaro Sagasti
- Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA
| | - Daniel J Goetschius
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
| | - Melissa M Rolls
- Biochemistry and Molecular Biology and the Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA
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17
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Xu A, Zhang Z, Ko SH, Fisher AL, Liu Z, Chen L. Microtubule regulators act in the nervous system to modulate fat metabolism and longevity through DAF-16 in C. elegans. Aging Cell 2019; 18:e12884. [PMID: 30638295 PMCID: PMC6413656 DOI: 10.1111/acel.12884] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 10/26/2018] [Accepted: 11/03/2018] [Indexed: 12/16/2022] Open
Abstract
Microtubule (MT) regulation is involved in both neuronal function and the maintenance of neuronal structure, and MT dysregulation appears to be a general downstream indicator and effector of age‐related neurodegeneration. But the role of MTs in natural aging is largely unknown. Here, we demonstrate a role of MT regulators in regulating longevity. We find that loss of EFA‐6, a modulator of MT dynamics, can delay both neuronal aging and extend the lifespan of C. elegans. Through the use of genetic mutants affecting other MT‐regulating genes in C. elegans, we find that loss of MT stabilizing genes (including ptrn‐1 and ptl‐1) shortens lifespan, while loss of MT destabilizing gene hdac‐6 extends lifespan. Via the use of tissue‐specific transgenes, we further show that these MT regulators can act in the nervous system to modulate lifespan. Through RNA‐seq analyses, we found that genes involved in lipid metabolism were differentially expressed in MT regulator mutants, and via the use of Nile Red and Oil Red O staining, we show that the MT regulator mutants have altered fat storage. We further find that the increased fat storage and extended lifespan of the long‐lived MT regulator mutants are dependent on the DAF‐16/FOXO transcription factor. Our results suggest that neuronal MT status might affect organismal aging through DAF‐16‐regulated changes in fat metabolism, and therefore, MT‐based therapies might represent a novel intervention to promote healthy aging.
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Affiliation(s)
- Aiping Xu
- Barshop Institute for Longevity and Aging Studies; San Antonio Texas
- Department of Cell Systems and Anatomy; UTHSCSA; San Antonio Texas
| | - Zhao Zhang
- Department of Molecular Medicine; UTHSCSA; San Antonio Texas
| | - Su-Hyuk Ko
- Barshop Institute for Longevity and Aging Studies; San Antonio Texas
- Department of Cell Systems and Anatomy; UTHSCSA; San Antonio Texas
- Department of Molecular Medicine; UTHSCSA; San Antonio Texas
| | - Alfred L. Fisher
- Center for Healthy Aging; UTHSCSA; San Antonio Texas
- Division of Geriatrics, Gerontology, and Palliative Medicine, Department of Medicine; UTHSCSA; San Antonio Texas
- GRECC, South Texas VA Healthcare System; San Antonio Texas
| | - Zhijie Liu
- Department of Molecular Medicine; UTHSCSA; San Antonio Texas
| | - Lizhen Chen
- Barshop Institute for Longevity and Aging Studies; San Antonio Texas
- Department of Cell Systems and Anatomy; UTHSCSA; San Antonio Texas
- Department of Molecular Medicine; UTHSCSA; San Antonio Texas
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18
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McLaughlin CN, Perry-Richardson JJ, Coutinho-Budd JC, Broihier HT. Dying Neurons Utilize Innate Immune Signaling to Prime Glia for Phagocytosis during Development. Dev Cell 2019; 48:506-522.e6. [PMID: 30745142 DOI: 10.1016/j.devcel.2018.12.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/19/2018] [Accepted: 12/21/2018] [Indexed: 02/06/2023]
Abstract
Glia continuously survey neuronal health during development, providing trophic support to healthy neurons while rapidly engulfing dying ones. These diametrically opposed functions necessitate a foolproof mechanism enabling glia to unambiguously identify those neurons to support versus those to engulf. To ensure specificity, glia are proposed to interact with dying neurons via a series of carefully choreographed steps. However, these crucial interactions are largely obscure. Here we show that dying neurons and glia communicate via Toll-receptor-regulated innate immune signaling. Neuronal apoptosis drives processing and activation of the Toll-6 ligand, Spätzle5. This cue activates a dSARM-mediated Toll-6 transcriptional pathway in glia, which controls the expression of the Draper engulfment receptor. Pathway loss drives early-onset neurodegeneration, underscoring its functional importance. Our results identify an upstream priming signal that prepares glia for phagocytosis. Thus, a core innate immune pathway plays an unprecedented role setting the valence of neuron-glia interactions during development.
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Affiliation(s)
- Colleen N McLaughlin
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
| | - Jahci J Perry-Richardson
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | | | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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19
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McLaughlin CN, Broihier HT. Keeping Neurons Young and Foxy: FoxOs Promote Neuronal Plasticity. Trends Genet 2018; 34:65-78. [PMID: 29102406 DOI: 10.1016/j.tig.2017.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/10/2017] [Accepted: 10/13/2017] [Indexed: 12/27/2022]
Abstract
Any adult who has tried to take up the piano or learn a new language is faced with the sobering realization that acquiring such skills is more challenging as an adult than as a child. Neuronal plasticity, or the malleability of brain circuits, declines with age. Young neurons tend to be more adaptable and can alter the size and strength of their connections more readily than can old neurons. Myriad circuit- and synapse-level mechanisms that shape plasticity have been identified. Yet, molecular mechanisms setting the overall competence of young neurons for distinct forms of plasticity remain largely obscure. Recent studies indicate evolutionarily conserved roles for FoxO proteins in establishing the capacity for cell-fate, morphological, and synaptic plasticity in neurons.
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Affiliation(s)
- Colleen N McLaughlin
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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20
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Muñoz-Soriano V, Belacortu Y, Sanz FJ, Solana-Manrique C, Dillon L, Suay-Corredera C, Ruiz-Romero M, Corominas M, Paricio N. Cbt modulates Foxo activation by positively regulating insulin signaling in Drosophila embryos. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2018; 1861:S1874-9399(18)30034-8. [PMID: 30055320 DOI: 10.1016/j.bbagrm.2018.07.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 07/10/2018] [Accepted: 07/19/2018] [Indexed: 01/05/2023]
Abstract
In late Drosophila embryos, the epidermis exhibits a dorsal hole as a consequence of germ band retraction. It is sealed during dorsal closure (DC), a morphogenetic process in which the two lateral epidermal layers converge towards the dorsal midline and fuse. We previously demonstrated the involvement of the Cbt transcription factor in Drosophila DC. However its molecular role in the process remained obscure. In this study, we used genomic approaches to identify genes regulated by Cbt as well as its direct targets during late embryogenesis. Our results reveal a complex transcriptional circuit downstream of Cbt and evidence that it is functionally related with the Insulin/insulin-like growth factor signaling pathway. In this context, Cbt may act as a positive regulator of the pathway, leading to the repression of Foxo activity. Our results also suggest that the DC defects observed in cbt embryos could be partially due to Foxo overactivation and that a regulatory feedback loop between Foxo and Cbt may be operating in the DC context.
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Affiliation(s)
- Verónica Muñoz-Soriano
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain; Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universitat de València, Dr Moliner 50, 46100 Burjassot, Spain
| | - Yaiza Belacortu
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain
| | - Francisco José Sanz
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain; Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universitat de València, Dr Moliner 50, 46100 Burjassot, Spain
| | - Cristina Solana-Manrique
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain; Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universitat de València, Dr Moliner 50, 46100 Burjassot, Spain
| | - Luke Dillon
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain
| | - Carmen Suay-Corredera
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain
| | - Marina Ruiz-Romero
- Departament de Genètica, Facultat de Biologia, and Institut de Biomedicina (IBUB) de la Universitat de Barcelona, Barcelona, Spain
| | - Montserrat Corominas
- Departament de Genètica, Facultat de Biologia, and Institut de Biomedicina (IBUB) de la Universitat de Barcelona, Barcelona, Spain
| | - Nuria Paricio
- Departamento de Genética, Facultad CC Biológicas, Universitat de València, 46100 Burjasot, Spain; Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED), Universitat de València, Dr Moliner 50, 46100 Burjassot, Spain.
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21
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Chen L. Microtubules and axon regeneration in C. elegans. Mol Cell Neurosci 2018; 91:160-166. [PMID: 29551667 DOI: 10.1016/j.mcn.2018.03.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/14/2018] [Accepted: 03/15/2018] [Indexed: 11/28/2022] Open
Abstract
Axon regeneration is a fundamental and conserved process that allows the nervous system to repair circuits after trauma. Due to its conserved genome, transparent body, and relatively simple neuroanatomy, C. elegans has become a powerful model organism for studying the cellular and molecular mechanisms underlying axon regeneration. Various studies from different model organisms have found microtubule dynamics to be pivotal to axon regrowth. In this review, we will discuss the latest findings on how microtubule dynamics are regulated during axon regeneration in C. elegans. Understanding the mechanisms of axon regeneration will aid in the development of more effective therapeutic strategies for treatments of diseases involving disconnection of axons, such as spinal cord injury and stroke.
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Affiliation(s)
- Lizhen Chen
- Barshop Institute for Longevity and Aging Studies, Department of Cell Systems and Anatomy, Department of Molecular Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA.
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22
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Tas D, Stickley L, Miozzo F, Koch R, Loncle N, Sabado V, Gnägi B, Nagoshi E. Parallel roles of transcription factors dFOXO and FER2 in the development and maintenance of dopaminergic neurons. PLoS Genet 2018. [PMID: 29529025 PMCID: PMC5864087 DOI: 10.1371/journal.pgen.1007271] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Forkhead box (FOXO) proteins are evolutionarily conserved, stress-responsive transcription factors (TFs) that can promote or counteract cell death. Mutations in FOXO genes are implicated in numerous pathologies, including age-dependent neurodegenerative disorders, such as Parkinson’s disease (PD). However, the complex regulation and downstream mechanisms of FOXOs present a challenge in understanding their roles in the pathogenesis of PD. Here, we investigate the involvement of FOXO in the death of dopaminergic (DA) neurons, the key pathological feature of PD, in Drosophila. We show that dFOXO null mutants exhibit a selective loss of DA neurons in the subgroup crucial for locomotion, the protocerebral anterior medial (PAM) cluster, during development as well as in adulthood. PAM neuron-targeted adult-restricted knockdown demonstrates that dFOXO in adult PAM neurons tissue-autonomously promotes neuronal survival during aging. We further show that dFOXO and the bHLH-TF 48-related-2 (FER2) act in parallel to protect PAM neurons from different forms of cellular stress. Remarkably, however, dFOXO and FER2 share common downstream processes leading to the regulation of autophagy and mitochondrial morphology. Thus, overexpression of one can rescue the loss of function of the other. These results indicate a role of dFOXO in neuroprotection and highlight the notion that multiple genetic and environmental factors interact to increase the risk of DA neuron degeneration and the development of PD. PD, mainly characterized by a progressive loss of dopaminergic neurons in the substantia nigra (SN), is the most prevalent neurodegenerative movement disorder affecting more than 6 million people worldwide. Despite the discovery of several genes linked to familial PD, our understanding of its pathogenesis remains limited, as approximately 90% of the PD cases are sporadic with no apparent genetic linkage. Genome-wide expression studies have implicated the stress-responsive TF FOXO in PD. However, the exact role of FOXO in the survival of DA neurons and PD pathogenesis is still poorly understood. Here, we use fruit flies to address the role of FOXO in the maintenance of DA neurons. dFOXO (Drosophila FOXO) null mutants show a progressive loss of DA neurons in the subgroup essential for locomotion, a phenotype identical to that of Fer2 mutants. Remarkably, dFOXO and FER2 act in parallel pathways to protect PAM neurons from different cellular stressors, but both pathways contribute to the regulation of autophagy and mitochondrial biology. These results demonstrate that dFOXO is required for the maintenance of DA neurons important for locomotion and shed new light on the molecular mechanisms underpinning the complex gene-environment interactions affecting DA neuron survival and PD pathogenesis.
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Affiliation(s)
- Damla Tas
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Luca Stickley
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Federico Miozzo
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Rafael Koch
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Nicolas Loncle
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Virginie Sabado
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
| | - Bettina Gnägi
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, Bern, CH, Switzerland
| | - Emi Nagoshi
- Department of Genetics and Evolution, Sciences III, University of Geneva, 30 Quai Ernest-Ansermet, Geneva-4, CH, Switzerland
- Institute of Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland
- * E-mail:
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23
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Multiplicity of acquired cross-resistance in paclitaxel-resistant cancer cells is associated with feedback control of TUBB3 via FOXO3a-mediated ABCB1 regulation. Oncotarget 2018; 7:34395-419. [PMID: 27284014 PMCID: PMC5085164 DOI: 10.18632/oncotarget.9118] [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: 02/17/2016] [Accepted: 04/11/2016] [Indexed: 12/22/2022] Open
Abstract
Acquired drug resistance is a primary obstacle for effective cancer therapy. The correlation of point mutations in class III β-tubulin (TUBB3) and the prominent overexpression of ATP-binding cassette P-glycoprotein (ABCB1), a multidrug resistance gene, have been protruding mechanisms of resistance to microtubule disruptors such as paclitaxel (PTX) for many cancers. However, the precise underlying mechanism of the rapid onset of cross-resistance to an array of structurally and functionally unrelated drugs in PTX-resistant cancers has been poorly understood. We determined that our established PTX-resistant cancer cells display ABCB1/ABCC1-associated cross-resistance to chemically different drugs such as 5-fluorouracil, docetaxel, and cisplatin. We found that feedback activation of TUBB3 can be triggered through the FOXO3a-dependent regulation of ABCB1, which resulted in the accentuation of induced PTX resistance and encouraged multiplicity in acquired cross-resistance. FOXO3a-directed regulation of P-glycoprotein (P-gp) function suggests that control of ABCB1 involves methylation-dependent activation. Consistently, transcriptional overexpression or downregulation of FOXO3a directs inhibitor-controlled protease-degradation of TUBB3. The functional PI3K/Akt signaling is tightly responsive to FOXO3a activation alongside doxorubicin treatment, which directs FOXO3a arginine hypermethylation. In addition, we found that secretome factors from PTX-resistant cancer cells with acquired cross-resistance support a P-gp-dependent association in multidrug resistance (MDR) development, which assisted the FOXO3a-mediated control of TUBB3 feedback. The direct silencing of TUBB3 reverses induced multiple cross-resistance, reduces drug-resistant tumor mass, and suppresses the impaired microtubule stability status of PTX-resistant cells with transient cross-resistance. These findings highlight the control of the TUBB3 response to ABCB1 genetic suppressors as a mechanism to reverse the profuse development of multidrug resistance in cancer.
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24
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Drosophila Kruppel homolog 1 represses lipolysis through interaction with dFOXO. Sci Rep 2017; 7:16369. [PMID: 29180716 PMCID: PMC5703730 DOI: 10.1038/s41598-017-16638-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 11/15/2017] [Indexed: 12/29/2022] Open
Abstract
Transcriptional coordination is a vital process contributing to metabolic homeostasis. As one of the key nodes in the metabolic network, the forkhead transcription factor FOXO has been shown to interact with diverse transcription co-factors and integrate signals from multiple pathways to control metabolism, oxidative stress response, and cell cycle. Recently, insulin/FOXO signaling has been implicated in the regulation of insect development via the interaction with insect hormones, such as ecdysone and juvenile hormone. In this study, we identified an interaction between Drosophila FOXO (dFOXO) and the zinc finger transcription factor Kruppel homolog 1 (Kr-h1), one of the key players in juvenile hormone signaling. We found that Kr-h1 mutants show delayed larval development and altered lipid metabolism, in particular induced lipolysis upon starvation. Notably, Kr-h1 physically and genetically interacts with dFOXO in vitro and in vivo to regulate the transcriptional activation of insulin receptor (InR) and adipose lipase brummer (bmm). The transcriptional co-regulation by Kr-h1 and dFOXO may represent a broad mechanism by which Kruppel-like factors integrate with insulin signaling to maintain metabolic homeostasis and coordinate organism growth.
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25
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Muroyama A, Lechler T. Microtubule organization, dynamics and functions in differentiated cells. Development 2017; 144:3012-3021. [PMID: 28851722 DOI: 10.1242/dev.153171] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Over the past several decades, numerous studies have greatly expanded our knowledge about how microtubule organization and dynamics are controlled in cultured cells in vitro However, our understanding of microtubule dynamics and functions in vivo, in differentiated cells and tissues, remains under-explored. Recent advances in generating genetic tools and imaging technologies to probe microtubules in situ, coupled with an increased interest in the functions of this cytoskeletal network in differentiated cells, are resulting in a renaissance. Here, we discuss the lessons learned from such approaches, which have revealed that, although some differentiated cells utilize conserved strategies to remodel microtubules, there is considerable diversity in the underlying molecular mechanisms of microtubule reorganization. This highlights a continued need to explore how differentiated cells regulate microtubule geometry in vivo.
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Affiliation(s)
- Andrew Muroyama
- Departments of Dermatology and Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Terry Lechler
- Departments of Dermatology and Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
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26
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Guo Y, Li Z, Shi C, Li J, Yao M, Chen X. Trichostatin A attenuates oxidative stress-mediated myocardial injury through the FoxO3a signaling pathway. Int J Mol Med 2017; 40:999-1008. [PMID: 28849190 PMCID: PMC5593460 DOI: 10.3892/ijmm.2017.3101] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 08/03/2017] [Indexed: 11/06/2022] Open
Abstract
Trichostatin A (TSA), a histone deacetylase inhibitor, is widely used as an anticancer drug. Recently, TSA has been shown to exert a protective effect on ischemia/reperfusion (I/R) injury; however, the underlying mechanisms remain unclear. Forkhead box O3a (FoxO3a), a unique FoxO family member, has been shown to attenuate myocardial injury by increasing resistance to oxidative stress in mice. The present study aimed to investigate whether TSA exerts its cardioprotective effects through the FoxO3a signaling pathway. For this purpose, healthy male Wistar rats were pre-treated with TSA for 5 days before they were subjected to ligation/relaxation of the left anterior descending branch of the coronary artery and to 30 min of ischemia, followed by 24 h of reperfusion. The activities of creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and superoxide diamutase (SOD), as well as the malondialdehyde (MDA) levels were examined. The H9c2 rat myocardial cell line was cultured in 10% FBS-containing DMEM for 24 h. The cells were incubated with/without TSA (50 nmol/l) for 1 h and then incubated with/without H2O2 (400 µM) for 2 h. Reactive oxygen species (ROS) and mitochondrial membrane potential (Δψm) were measured by probe staining in the H9c2 cells. The expression of FoxO3a, mitochondrial SOD2 and catalase was quantified by western blot analysis. The levels of H3 and H4 acetylation of the FoxO3a promoter region were examined by chromatin immunoprecipitation assay. TSA significantly reduced the myocardial infarct size and the activities of serum LDH, AST and CK in the rats. TSA also decreased the levels of MDA and increased the activities of SOD in the myocardial tissue of the rats. Consistent with the reduced injury to the TSA-treated rats, TSA significantly reduced the H2O2-induced levels of ROS and increased Δψm. In addition, TSA increased the expression of FoxO3a, SOD2 and catalase, which may be related to increasing the level of H4 acetylation of the FoxO3a promoter region. Our results thus revealed that TSA protected the myocardium from oxidative stress-mediated damage by increasing H4 acetylation of the FoxO3a promoter region, and the expression of FoxO3a, SOD2 and catalase.
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Affiliation(s)
- Yunhui Guo
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Zhiping Li
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Canxia Shi
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jia Li
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Meng Yao
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Xia Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
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27
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Nishida T, Yoshimura R, Endo Y. Three-dimensional fine structure of the organization of microtubules in neurite varicosities by ultra-high voltage electron microscope tomography. Cell Tissue Res 2017. [PMID: 28646303 DOI: 10.1007/s00441-017-2645-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Neurite varicosities are highly specialized compartments that are involved in neurotransmitter/ neuromodulator release and provide a physiological platform for neural functions. However, it remains unclear how microtubule organization contributes to the form of varicosity. Here, we examine the three-dimensional structure of microtubules in varicosities of a differentiated PC12 neural cell line using ultra-high voltage electron microscope tomography. Three-dimensional imaging showed that a part of the varicosities contained an accumulation of organelles that were separated from parallel microtubule arrays. Further detailed analysis using serial sections and whole-mount tomography revealed microtubules running in a spindle shape of swelling in some other types of varicosities. These electron tomographic results showed that the structural diversity and heterogeneity of microtubule organization supported the form of varicosities, suggesting that a different distribution pattern of microtubules in varicosities is crucial to the regulation of varicosities development.
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Affiliation(s)
- Tomoki Nishida
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Osaka, Ibaraki, 567-0047, Japan.
- Japan Textile Products Quality and Technology Center, 5-7-3, Shimoyamate St, Chuo-ku, Kobe, Hyogo, 650-0011, Japan.
| | - Ryoichi Yoshimura
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Yasuhisa Endo
- Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
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28
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Farina F, Lambert E, Commeau L, Lejeune FX, Roudier N, Fonte C, Parker JA, Boddaert J, Verny M, Baulieu EE, Neri C. The stress response factor daf-16/FOXO is required for multiple compound families to prolong the function of neurons with Huntington's disease. Sci Rep 2017. [PMID: 28638078 PMCID: PMC5479833 DOI: 10.1038/s41598-017-04256-w] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Helping neurons to compensate for proteotoxic stress and maintain function over time (neuronal compensation) has therapeutic potential in aging and neurodegenerative disease. The stress response factor FOXO3 is neuroprotective in models of Huntington’s disease (HD), Parkinson’s disease and motor-neuron diseases. Neuroprotective compounds acting in a FOXO-dependent manner could thus constitute bona fide drugs for promoting neuronal compensation. However, whether FOXO-dependent neuroprotection is a common feature of several compound families remains unknown. Using drug screening in C. elegans nematodes with neuronal expression of human exon-1 huntingtin (128Q), we found that 3ß-Methoxy-Pregnenolone (MAP4343), 17ß-oestradiol (17ßE2) and 12 flavonoids including isoquercitrin promote neuronal function in 128Q nematodes. MAP4343, 17ßE2 and isoquercitrin also promote stress resistance in mutant Htt striatal cells derived from knock-in HD mice. Interestingly, daf-16/FOXO is required for MAP4343, 17ßE2 and isoquercitrin to sustain neuronal function in 128Q nematodes. This similarly applies to the GSK3 inhibitor lithium chloride (LiCl) and, as previously described, to resveratrol and the AMPK activator metformin. Daf-16/FOXO and the targets engaged by these compounds define a sub-network enriched for stress-response and neuronally-active pathways. Collectively, these data highlights the dependence on a daf-16/FOXO-interaction network as a common feature of several compound families for prolonging neuronal function in HD.
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Affiliation(s)
- Francesca Farina
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France
| | - Emmanuel Lambert
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France
| | - Lucie Commeau
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France
| | - François-Xavier Lejeune
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France
| | | | - Cosima Fonte
- Inserm, UMR 1195, 94276, Le Kremlin-Bicêtre, Cedex, France
| | - J Alex Parker
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France.,CRCHUM, Montréal, Canada and Department de Neurosciences, Faculté de médecine, Université de Montréal, Montréal, Canada
| | - Jacques Boddaert
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France.,Department of Geriatrics, Pitié-Salpêtrière Hospital, Assistance Publique Hôpitaux de Paris (APHP), 75013, Paris, France
| | - Marc Verny
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France.,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France.,Department of Geriatrics, Pitié-Salpêtrière Hospital, Assistance Publique Hôpitaux de Paris (APHP), 75013, Paris, France
| | - Etienne-Emile Baulieu
- Inserm, UMR 1195, 94276, Le Kremlin-Bicêtre, Cedex, France. .,MAPREG, 94276, Le Kremlin-Bicêtre, Cedex, France.
| | - Christian Neri
- CNRS, Laboratory of Neuronal Cell Biology & Pathology and University Hospital Department Fight Aging and Stress (DHU FAST), UMR 8256, Paris, France. .,Sorbonne Universités, University Pierre and Marie Curie (UPMC) Univ Paris 06, Paris, France.
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29
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O'Connor-Giles K. Toll-tally tubular: A newly identified Toll-like receptor-FoxO pathway regulates dynamics of the neuronal microtubule network. J Cell Biol 2017; 214:371-3. [PMID: 27528655 PMCID: PMC4987299 DOI: 10.1083/jcb.201607118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 07/29/2016] [Indexed: 11/22/2022] Open
Abstract
Recent studies reveal a conserved role for FoxO transcription factors in establishing neuronal structure and circuit function. In this issue, McLaughlin et al. (2016. J. Cell Biol.http://dx.doi.org/10.1083/jcb.201601014) identify a novel Toll-like receptor–FoxO pathway that represses the mitotic kinesin Pavarotti/MKLP1 to promote dynamic microtubules required for axonal transport and activity-dependent remodeling of presynaptic terminals.
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30
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Kang MJ, Vasudevan D, Kang K, Kim K, Park JE, Zhang N, Zeng X, Neubert TA, Marr MT, Ryoo HD. 4E-BP is a target of the GCN2-ATF4 pathway during Drosophila development and aging. J Cell Biol 2016; 216:115-129. [PMID: 27979906 PMCID: PMC5223598 DOI: 10.1083/jcb.201511073] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Revised: 04/19/2016] [Accepted: 11/17/2016] [Indexed: 12/31/2022] Open
Abstract
Kang et al. show that the GCN2–ATF4 pathway induces 4E-BP transcription in response to amino acid deprivation and also during the development of certain Drosophila tissues. 4E-BP has selective effects on translation; therefore, this pathway helps to shift the mRNA expression profiles of cells. Reduced amino acid availability attenuates mRNA translation in cells and helps to extend lifespan in model organisms. The amino acid deprivation–activated kinase GCN2 mediates this response in part by phosphorylating eIF2α. In addition, the cap-dependent translational inhibitor 4E-BP is transcriptionally induced to extend lifespan in Drosophila melanogaster, but through an unclear mechanism. Here, we show that GCN2 and its downstream transcription factor, ATF4, mediate 4E-BP induction, and GCN2 is required for lifespan extension in response to dietary restriction of amino acids. The 4E-BP intron contains ATF4-binding sites that not only respond to stress but also show inherent ATF4 activity during normal development. Analysis of the newly synthesized proteome through metabolic labeling combined with click chemistry shows that certain stress-responsive proteins are resistant to inhibition by 4E-BP, and gcn2 mutant flies have reduced levels of stress-responsive protein synthesis. These results indicate that GCN2 and ATF4 are important regulators of 4E-BP transcription during normal development and aging.
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Affiliation(s)
- Min-Ji Kang
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016 .,Department of Biomedical Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Deepika Vasudevan
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016
| | - Kwonyoon Kang
- Department of Biomedical Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Kyunggon Kim
- Proteomics Core Laboratory, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Jung-Eun Park
- Department of Biomedical Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Nan Zhang
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016
| | - Xiaomei Zeng
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016
| | - Thomas A Neubert
- Department of Biochemistry and Molecular Pharmacology, Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY 10016
| | - Michael T Marr
- Department of Biology, Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02453
| | - Hyung Don Ryoo
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016
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31
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Sears JC, Broihier HT. FoxO regulates microtubule dynamics and polarity to promote dendrite branching in Drosophila sensory neurons. Dev Biol 2016; 418:40-54. [PMID: 27546375 DOI: 10.1016/j.ydbio.2016.08.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 08/12/2016] [Accepted: 08/16/2016] [Indexed: 01/15/2023]
Abstract
The size and shape of dendrite arbors are defining features of neurons and critical determinants of neuronal function. The molecular mechanisms establishing arborization patterns during development are not well understood, though properly regulated microtubule (MT) dynamics and polarity are essential. We previously found that FoxO regulates axonal MTs, raising the question of whether it also regulates dendritic MTs and morphology. Here we demonstrate that FoxO promotes dendrite branching in all classes of Drosophila dendritic arborization (da) neurons. FoxO is required both for initiating growth of new branches and for maintaining existing branches. To elucidate FoxO function, we characterized MT organization in both foxO null and overexpressing neurons. We find that FoxO directs MT organization and dynamics in dendrites. Moreover, it is both necessary and sufficient for anterograde MT polymerization, which is known to promote dendrite branching. Lastly, FoxO promotes proper larval nociception, indicating a functional consequence of impaired da neuron morphology in foxO mutants. Together, our results indicate that FoxO regulates dendrite structure and function and suggest that FoxO-mediated pathways control MT dynamics and polarity.
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Affiliation(s)
- James C Sears
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106, USA.
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32
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Mahoney RE, Azpurua J, Eaton BA. Insulin signaling controls neurotransmission via the 4eBP-dependent modification of the exocytotic machinery. eLife 2016; 5:e16807. [PMID: 27525480 PMCID: PMC5012858 DOI: 10.7554/elife.16807] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 08/14/2016] [Indexed: 12/26/2022] Open
Abstract
Altered insulin signaling has been linked to widespread nervous system dysfunction including cognitive dysfunction, neuropathy and susceptibility to neurodegenerative disease. However, knowledge of the cellular mechanisms underlying the effects of insulin on neuronal function is incomplete. Here, we show that cell autonomous insulin signaling within the Drosophila CM9 motor neuron regulates the release of neurotransmitter via alteration of the synaptic vesicle fusion machinery. This effect of insulin utilizes the FOXO-dependent regulation of the thor gene, which encodes the Drosophila homologue of the eif-4e binding protein (4eBP). A critical target of this regulatory mechanism is Complexin, a synaptic protein known to regulate synaptic vesicle exocytosis. We find that the amounts of Complexin protein observed at the synapse is regulated by insulin and genetic manipulations of Complexin levels support the model that increased synaptic Complexin reduces neurotransmission in response to insulin signaling.
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Affiliation(s)
- Rebekah Elizabeth Mahoney
- Department of Physiology, University of Texas Health Sciences Center at San Antonio, San Antonio, United States
- Barshop Institute of Aging and Longevity Studies, University of Texas Health Sciences Center at San Antonio, San Antonio, United States
| | - Jorge Azpurua
- Department of Physiology, University of Texas Health Sciences Center at San Antonio, San Antonio, United States
| | - Benjamin A Eaton
- Department of Physiology, University of Texas Health Sciences Center at San Antonio, San Antonio, United States
- Barshop Institute of Aging and Longevity Studies, University of Texas Health Sciences Center at San Antonio, San Antonio, United States
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33
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McLaughlin CN, Nechipurenko IV, Liu N, Broihier HT. A Toll receptor-FoxO pathway represses Pavarotti/MKLP1 to promote microtubule dynamics in motoneurons. J Cell Biol 2016; 214:459-74. [PMID: 27502486 PMCID: PMC4987293 DOI: 10.1083/jcb.201601014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 07/07/2016] [Indexed: 02/06/2023] Open
Abstract
McLaughlin et al. uncover a motoneuronal Toll-6–directed pathway that functions via dSARM and FoxO to attenuate microtubule stability through repression of Pavarotti/MKLP1 transcription. Genetic and pharmacological strategies reveal a novel requirement for dynamic synaptic microtubules in structural plasticity, which are established by Toll-6–FoxO signaling. FoxO proteins are evolutionarily conserved regulators of neuronal structure and function, yet the neuron-specific pathways within which they act are poorly understood. To elucidate neuronal FoxO function in Drosophila melanogaster, we first screened for FoxO’s upstream regulators and downstream effectors. On the upstream side, we present genetic and molecular pathway analyses indicating that the Toll-6 receptor, the Toll/interleukin-1 receptor domain adaptor dSARM, and FoxO function in a linear pathway. On the downstream side, we find that Toll-6–FoxO signaling represses the mitotic kinesin Pavarotti/MKLP1 (Pav-KLP), which itself attenuates microtubule (MT) dynamics. We next probed in vivo functions for this novel pathway and found that it is essential for axon transport and structural plasticity in motoneurons. We demonstrate that elevated expression of Pav-KLP underlies transport and plasticity phenotypes in pathway mutants, indicating that Toll-6–FoxO signaling promotes MT dynamics by limiting Pav-KLP expression. In addition to uncovering a novel molecular pathway, our work reveals an unexpected function for dynamic MTs in enabling rapid activity-dependent structural plasticity.
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Affiliation(s)
- Colleen N McLaughlin
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106
| | - Inna V Nechipurenko
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106
| | - Nan Liu
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106
| | - Heather T Broihier
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106
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Bodaleo FJ, Gonzalez-Billault C. The Presynaptic Microtubule Cytoskeleton in Physiological and Pathological Conditions: Lessons from Drosophila Fragile X Syndrome and Hereditary Spastic Paraplegias. Front Mol Neurosci 2016; 9:60. [PMID: 27504085 PMCID: PMC4958632 DOI: 10.3389/fnmol.2016.00060] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/11/2016] [Indexed: 11/21/2022] Open
Abstract
The capacity of the nervous system to generate neuronal networks relies on the establishment and maintenance of synaptic contacts. Synapses are composed of functionally different presynaptic and postsynaptic compartments. An appropriate synaptic architecture is required to provide the structural basis that supports synaptic transmission, a process involving changes in cytoskeletal dynamics. Actin microfilaments are the main cytoskeletal components present at both presynaptic and postsynaptic terminals in glutamatergic synapses. However, in the last few years it has been demonstrated that microtubules (MTs) transiently invade dendritic spines, promoting their maturation. Nevertheless, the presence and functions of MTs at the presynaptic site are still a matter of debate. Early electron microscopy (EM) studies revealed that MTs are present in the presynaptic terminals of the central nervous system (CNS) where they interact with synaptic vesicles (SVs) and reach the active zone. These observations have been reproduced by several EM protocols; however, there is empirical heterogeneity in detecting presynaptic MTs, since they appear to be both labile and unstable. Moreover, increasing evidence derived from studies in the fruit fly neuromuscular junction proposes different roles for MTs in regulating presynaptic function in physiological and pathological conditions. In this review, we summarize the main findings that support the presence and roles of MTs at presynaptic terminals, integrating descriptive and biochemical analyses, and studies performed in invertebrate genetic models.
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Affiliation(s)
- Felipe J Bodaleo
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile
| | - Christian Gonzalez-Billault
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile; The Buck Institute for Research on Aging, NovatoCA, USA
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35
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Forkhead box O transcription factors as possible mediators in the development of major depression. Neuropharmacology 2015; 99:527-37. [DOI: 10.1016/j.neuropharm.2015.08.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 07/22/2015] [Accepted: 08/12/2015] [Indexed: 01/26/2023]
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Wu C, Chen Y, Wang F, Chen C, Zhang S, Li C, Li W, Wu S, Xue L. Pelle Modulates dFoxO-Mediated Cell Death in Drosophila. PLoS Genet 2015; 11:e1005589. [PMID: 26474173 PMCID: PMC4608839 DOI: 10.1371/journal.pgen.1005589] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 09/17/2015] [Indexed: 12/31/2022] Open
Abstract
Interleukin-1 receptor-associated kinases (IRAKs) are crucial mediators of the IL-1R/TLR signaling pathways that regulate the immune and inflammation response in mammals. Recent studies also suggest a critical role of IRAKs in tumor development, though the underlying mechanism remains elusive. Pelle is the sole Drosophila IRAK homolog implicated in the conserved Toll pathway that regulates Dorsal/Ventral patterning, innate immune response, muscle development and axon guidance. Here we report a novel function of pll in modulating apoptotic cell death, which is independent of the Toll pathway. We found that loss of pll results in reduced size in wing tissue, which is caused by a reduction in cell number but not cell size. Depletion of pll up-regulates the transcription of pro-apoptotic genes, and triggers caspase activation and cell death. The transcription factor dFoxO is required for loss-of-pll induced cell death. Furthermore, loss of pll activates dFoxO, promotes its translocation from cytoplasm to nucleus, and up-regulates the transcription of its target gene Thor/4E-BP. Finally, Pll physically interacts with dFoxO and phosphorylates dFoxO directly. This study not only identifies a previously unknown physiological function of pll in cell death, but also shed light on the mechanism of IRAKs in cell survival/death during tumorigenesis.
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Affiliation(s)
- Chenxi Wu
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Yujun Chen
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Feng Wang
- State Key Laboratory of Medicinal Chemical Biology and College of Life Sciences, Nankai University, Tianjin, China
| | - Changyan Chen
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Shiping Zhang
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Chaojie Li
- State Key Laboratory of Medicinal Chemical Biology and College of Life Sciences, Nankai University, Tianjin, China
| | - Wenzhe Li
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Shian Wu
- State Key Laboratory of Medicinal Chemical Biology and College of Life Sciences, Nankai University, Tianjin, China
| | - Lei Xue
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
- * E-mail:
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Hu Y, Han Y, Shao Y, Wang X, Ma Y, Ling E, Xue L. Gr33a modulates Drosophila male courtship preference. Sci Rep 2015; 5:7777. [PMID: 25586066 PMCID: PMC4648378 DOI: 10.1038/srep07777] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 12/10/2014] [Indexed: 11/30/2022] Open
Abstract
In any gamogenetic species, attraction between individuals of the opposite sex promotes reproductive success that guarantees their thriving. Consequently, mate determination between two sexes is effortless for an animal. However, choosing a spouse from numerous attractive partners of the opposite sex needs deliberation. In Drosophila melanogaster, both younger virgin females and older ones are equally liked options to males; nevertheless, when given options, males prefer younger females to older ones. Non-volatile cuticular hydrocarbons, considered as major pheromones in Drosophila, constitute females' sexual attraction that act through males' gustatory receptors (Grs) to elicit male courtship. To date, only a few putative Grs are known to play roles in male courtship. Here we report that loss of Gr33a function or abrogating the activity of Gr33a neurons does not disrupt male-female courtship, but eliminates males' preference for younger mates. Furthermore, ectopic expression of human amyloid precursor protein (APP) in Gr33a neurons abolishes males' preference behavior. Such function of APP is mediated by the transcription factor forkhead box O (dFoxO). These results not only provide mechanistic insights into Drosophila male courtship preference, but also establish a novel Drosophila model for Alzheimer's disease (AD).
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Affiliation(s)
- Yujia Hu
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yi Han
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yingyao Shao
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Xingjun Wang
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yeqing Ma
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Erjun Ling
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lei Xue
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
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Aleyasin H, Karuppagounder SS, Kumar A, Sleiman S, Basso M, Ma T, Siddiq A, Chinta SJ, Brochier C, Langley B, Haskew-Layton R, Bane SL, Riggins GJ, Gazaryan I, Starkov AA, Andersen JK, Ratan RR. Antihelminthic benzimidazoles are novel HIF activators that prevent oxidative neuronal death via binding to tubulin. Antioxid Redox Signal 2015; 22:121-34. [PMID: 24766300 PMCID: PMC4281859 DOI: 10.1089/ars.2013.5595] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AIMS Pharmacological activation of the adaptive response to hypoxia is a therapeutic strategy of growing interest for neurological conditions, including stroke, Huntington's disease, and Parkinson's disease. We screened a drug library with known safety in humans using a hippocampal neuroblast line expressing a reporter of hypoxia-inducible factor (HIF)-dependent transcription. RESULTS Our screen identified more than 40 compounds with the ability to induce hypoxia response element-driven luciferase activity as well or better than deferoxamine, a canonical activator of hypoxic adaptation. Among the chemical entities identified, the antihelminthic benzimidazoles represented one pharmacophore that appeared multiple times in our screen. Secondary assays confirmed that antihelminthics stabilized the transcriptional activator HIF-1α and induced expression of a known HIF target gene, p21(cip1/waf1), in post-mitotic cortical neurons. The on-target effect of these agents in stimulating hypoxic signaling was binding to free tubulin. Moreover, antihelminthic benzimidazoles also abrogated oxidative stress-induced death in vitro, and this on-target effect also involves binding to free tubulin. INNOVATION AND CONCLUSIONS These studies demonstrate that tubulin-binding drugs can activate a component of the hypoxic adaptive response, specifically the stabilization of HIF-1α and its downstream targets. Tubulin-binding drugs, including antihelminthic benzimidazoles, also abrogate oxidative neuronal death in primary neurons. Given their safety in humans and known ability to penetrate into the central nervous system, antihelminthic benzimidazoles may be considered viable candidates for treating diseases associated with oxidative neuronal death, including stroke.
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Affiliation(s)
- Hossein Aleyasin
- 1 Burke-Cornell Medical Research Institute , White Plains, New York
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Pavlikova N, Weiszenstein M, Pala J, Halada P, Seda O, Elkalaf M, Trnka J, Kovar J, Polak J. The effect of cultureware surfaces on functional and structural components of differentiated 3T3-L1 preadipocytes. ACTA ACUST UNITED AC 2015; 20:919-36. [DOI: 10.1515/cmble-2015-0054] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Accepted: 11/13/2015] [Indexed: 01/21/2023]
Abstract
AbstractExperiments using cultured primary cells or cell lines are a routine in vitro approach used across multiple biological disciplines, However, the structural and functional influences of various cultureware materials on cultured cells is not clearly understood. Surface treatments of cultureware have proven to have profound effects on cell viability and proliferation. In this study, we investigated the impact of polystyrene and fluorocarbon cultureware dishes on the proteomic profile of differentiated 3T3-L1 preadipocytes. After expansion and differentiation of cells on appropriate cultureware dishes, cell lysates were separated using two-dimensional gel electrophoresis and proteins were visualized with Coomassie blue staining. Spots with the highest differential expression between the two culture conditions were subsequently analyzed using matrix-assisted laser desorption/ionization mass spectrometry and the identified proteins were subjected to pathway analysis. We observed that 43% of all spots were differentially expressed depending on the cultureware. Pathway analysis revealed that glucose metabolism, mitochondrial structure and cell differentiation, represented by 14-3-3 protein-mediated signaling and the mitochondrial inner membrane organizing system (MINOS), were significantly affected by cultureware material. These results indicate that cultureware material can have a profound effect on key adipocyte functional pathways. These effects modifications of the cells should be reflected in the design of in vitro experiments and interpretation of their results.
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40
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Crimpy enables discrimination of presynaptic and postsynaptic pools of a BMP at the Drosophila neuromuscular junction. Dev Cell 2014; 31:586-98. [PMID: 25453556 DOI: 10.1016/j.devcel.2014.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 09/07/2014] [Accepted: 10/03/2014] [Indexed: 01/22/2023]
Abstract
Distinct pools of the bone morphogenetic protein (BMP) Glass bottom boat (Gbb) control structure and function of the Drosophila neuromuscular junction. Specifically, motoneuron-derived Gbb regulates baseline neurotransmitter release, whereas muscle-derived Gbb regulates neuromuscular junction growth. Yet how cells differentiate between these ligand pools is not known. Here we present evidence that the neuronal Gbb-binding protein Crimpy (Cmpy) permits discrimination of pre- and postsynaptic ligand by serving sequential functions in Gbb signaling. Cmpy first delivers Gbb to dense core vesicles (DCVs) for activity-dependent release from presynaptic terminals. In the absence of Cmpy, Gbb is no longer associated with DCVs and is not released by activity. Electrophysiological analyses demonstrate that Cmpy promotes Gbb's proneurotransmission function. Surprisingly, the Cmpy ectodomain is itself released upon DCV exocytosis, arguing that Cmpy serves a second function in BMP signaling. In addition to trafficking Gbb to DCVs, we propose that Gbb/Cmpy corelease from presynaptic terminals defines a neuronal protransmission signal.
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41
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Heckscher ES, Long F, Layden MJ, Chuang CH, Manning L, Richart J, Pearson JC, Crews ST, Peng H, Myers E, Doe CQ. Atlas-builder software and the eNeuro atlas: resources for developmental biology and neuroscience. Development 2014; 141:2524-32. [PMID: 24917506 DOI: 10.1242/dev.108720] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A major limitation in understanding embryonic development is the lack of cell type-specific markers. Existing gene expression and marker atlases provide valuable tools, but they typically have one or more limitations: a lack of single-cell resolution; an inability to register multiple expression patterns to determine their precise relationship; an inability to be upgraded by users; an inability to compare novel patterns with the database patterns; and a lack of three-dimensional images. Here, we develop new 'atlas-builder' software that overcomes each of these limitations. A newly generated atlas is three-dimensional, allows the precise registration of an infinite number of cell type-specific markers, is searchable and is open-ended. Our software can be used to create an atlas of any tissue in any organism that contains stereotyped cell positions. We used the software to generate an 'eNeuro' atlas of the Drosophila embryonic CNS containing eight transcription factors that mark the major CNS cell types (motor neurons, glia, neurosecretory cells and interneurons). We found neuronal, but not glial, nuclei occupied stereotyped locations. We added 75 new Gal4 markers to the atlas to identify over 50% of all interneurons in the ventral CNS, and these lines allowed functional access to those interneurons for the first time. We expect the atlas-builder software to benefit a large proportion of the developmental biology community, and the eNeuro atlas to serve as a publicly accessible hub for integrating neuronal attributes - cell lineage, gene expression patterns, axon/dendrite projections, neurotransmitters--and linking them to individual neurons.
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Affiliation(s)
- Ellie S Heckscher
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
| | - Fuhui Long
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Michael J Layden
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
| | - Chein-Hui Chuang
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
| | - Laurina Manning
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
| | - Jourdain Richart
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
| | - Joseph C Pearson
- Program in Molecular Biology and Biophysics, Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 275995, USA
| | - Stephen T Crews
- Program in Molecular Biology and Biophysics, Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 275995, USA
| | - Hanchuan Peng
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Eugene Myers
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Chris Q Doe
- Institute of Neuroscience, Institute of Molecular Biology, Howard Hughes Medical Institute, University of Oregon, Eugene, OR 97403, USA
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Wang X, Wang Z, Chen Y, Huang X, Hu Y, Zhang R, Ho MS, Xue L. FoxO mediates APP-induced AICD-dependent cell death. Cell Death Dis 2014; 5:e1233. [PMID: 24832605 PMCID: PMC4047897 DOI: 10.1038/cddis.2014.196] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 02/04/2014] [Accepted: 04/01/2014] [Indexed: 12/28/2022]
Abstract
The amyloid precursor protein (APP) is a broadly expressed transmembrane protein that has a significant role in the pathogenesis of Alzheimer's disease (AD). APP can be cleaved at multiple sites to generate a series of fragments including the amyloid β (Aβ) peptides and APP intracellular domain (AICD). Although Aβ peptides have been proposed to be the main cause of AD pathogenesis, the role of AICD has been underappreciated. Here we report that APP induces AICD-dependent cell death in Drosophila neuronal and non-neuronal tissues. Our genetic screen identified the transcription factor forkhead box O (FoxO) as a crucial downstream mediator of APP-induced cell death and locomotion defect. In mammalian cells, AICD physically interacts with FoxO in the cytoplasm, translocates with FoxO into the nucleus upon oxidative stress, and promotes FoxO-induced transcription of pro-apoptotic gene Bim. These data demonstrate that APP modulates FoxO-mediated cell death through AICD, which acts as a transcriptional co-activator of FoxO.
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Affiliation(s)
- X Wang
- 1] Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China [2]
| | - Z Wang
- 1] Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China [2]
| | - Y Chen
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - X Huang
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - Y Hu
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - R Zhang
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
| | - M S Ho
- Department of Anatomy and Neurobiology, School of Medicine, Tongji University, Shanghai, China
| | - L Xue
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai, China
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Abstract
The post-genomic era has produced a variety of new investigation technologies, techniques and approaches that may offer exciting insights into many long-standing questions of scientific research. The microtubule cytoskeleton is a highly conserved system that shows a high degree of internal complexity, is known to be integral to many cell systems and functions on a fundamental level. After decades of study, much is still unknown about microtubules in vivo from the control of dynamics in living cells to their responses to environmental changes and responses to other cellular processes. In the present article, we examine some outstanding questions in the microtubule field and propose a combination of emerging interdisciplinary approaches, i.e. high-throughput functional genomics techniques, quantitative and super-resolution microscopy, and in silico modelling, that could shed light on the systemic regulation of microtubules in cells by networks of regulatory factors. We propose that such an integrative approach is key to elucidate the function of the microtubule cytoskeleton as a complete responsive integral biological system.
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Abstract
Axon regeneration after damage is widespread in the animal kingdom, and the nematode Caenorhabditis elegans has recently emerged as a tractable model in which to study the genetics and cell biology of axon regrowth in vivo. A key early step in axon regrowth is the conversion of part of a mature axon shaft into a growth cone-like structure, involving coordinated alterations in the microtubule, actin, and neurofilament systems. Recent attention has focused on microtubule dynamics as a determinant of axon-regrowth ability in several organisms. Live imaging studies have begun to reveal how the microtubule cytoskeleton is remodeled after axon injury, as well as the regulatory pathways involved. The dual leucine zipper kinase family of mixed-lineage kinases has emerged as a critical sensor of axon damage and plays a key role in regulating microtubule dynamics in the damaged axon.
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Affiliation(s)
- Andrew D Chisholm
- Division of Biological Sciences, Section of Neurobiology, University of California, San Diego, La Jolla, California 92093;
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45
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Natarajan R, Trivedi-Vyas D, Wairkar YP. Tuberous sclerosis complex regulates Drosophila neuromuscular junction growth via the TORC2/Akt pathway. Hum Mol Genet 2013; 22:2010-23. [PMID: 23393158 DOI: 10.1093/hmg/ddt053] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mutations in the tuberous sclerosis complex (TSC) are associated with various forms of neurodevelopmental disorders, including autism and epilepsy. The heterodimeric TSC complex, consisting of Tsc1 and Tsc2 proteins, regulates the activity of the TOR (target of rapamycin) complex via Rheb, a small GTPase. TOR, an atypical serine/threonine kinase, forms two distinct complexes TORC1 and TORC2. Raptor and Rictor serve as specific functional components of TORC1 and TORC2, respectively. Previous studies have identified Tsc1 as a regulator of hippocampal neuronal morphology and function via the TOR pathway, but it is unclear whether this is mediated via TORC1 or TORC2. In a genetic screen for aberrant synaptic growth at the neuromuscular junctions (NMJs) in Drosophila, we identified that Tsc2 mutants showed increased synaptic growth. Increased synaptic growth was also observed in rictor mutants, while raptor knockdown did not phenocopy the TSC mutant phenotype, suggesting that a novel role exists for TORC2 in regulating synapse growth. Furthermore, Tsc2 mutants showed a dramatic decrease in the levels of phosphorylated Akt, and interestingly, Akt mutants phenocopied Tsc2 mutants, leading to the hypothesis that Tsc2 and Akt might work via the same genetic pathway to regulate synapse growth. Indeed, transheterozygous analysis of Tsc2 and Akt mutants confirmed this hypothesis. Finally, our data also suggest that while overexpression of rheb results in aberrant synaptic overgrowth, the overgrowth might be independent of TORC2. Thus, we propose that at the Drosophila NMJ, TSC regulates synaptic growth via the TORC2-Akt pathway.
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Affiliation(s)
- Rajalaxmi Natarajan
- Department of Neurology, and George and Cynthia Mitchell Center for Neurodegenerative Diseases, University ofTexas Medical Branch, 301 University Blvd., Galveston, TX 77555, USA
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Ludueña RF. A Hypothesis on the Origin and Evolution of Tubulin. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 302:41-185. [DOI: 10.1016/b978-0-12-407699-0.00002-9] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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