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Okamoto N, Yamanaka N. Nutrition-dependent control of insect development by insulin-like peptides. CURRENT OPINION IN INSECT SCIENCE 2015; 11:21-30. [PMID: 26664828 PMCID: PMC4671074 DOI: 10.1016/j.cois.2015.08.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In metazoans, members of the insulin-like peptide (ILP) family play a role in multiple physiological functions in response to the nutritional status. ILPs have been identified and characterized in a wide variety of insect species. Insect ILPs that are mainly produced by several pairs of medial neurosecretory cells in the brain circulate in the hemolymph and act systemically on target tissues. Physiological and biochemical studies in Lepidoptera and genetic studies in the fruit fly have greatly expanded our knowledge of the physiological functions of ILPs. Here, we outline the recent progress of the structural classification of insect ILPs and overview recent studies that have elucidated the physiological functions of insect ILPs involved in nutrient-dependent growth during development.
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Affiliation(s)
- Naoki Okamoto
- Department of Entomology, Institute for Integrative Genome Biology, Center for Disease Vector Research, University of California, Riverside, Riverside, CA 92521, USA
| | - Naoki Yamanaka
- Department of Entomology, Institute for Integrative Genome Biology, Center for Disease Vector Research, University of California, Riverside, Riverside, CA 92521, USA
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Lavrynenko O, Rodenfels J, Carvalho M, Dye NA, Lafont R, Eaton S, Shevchenko A. The ecdysteroidome of Drosophila: influence of diet and development. Development 2015; 142:3758-68. [PMID: 26395481 DOI: 10.1242/dev.124982] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 09/03/2015] [Indexed: 01/06/2023]
Abstract
Ecdysteroids are the hormones regulating development, physiology and fertility in arthropods, which synthesize them exclusively from dietary sterols. But how dietary sterol diversity influences the ecdysteroid profile, how animals ensure the production of desired hormones and whether there are functional differences between different ecdysteroids produced in vivo remains unknown. This is because currently there is no analytical technology for unbiased, comprehensive and quantitative assessment of the full complement of endogenous ecdysteroids. We developed a new LC-MS/MS method to screen the entire chemical space of ecdysteroid-related structures and to quantify known and newly discovered hormones and their catabolites. We quantified the ecdysteroidome in Drosophila melanogaster and investigated how the ecdysteroid profile varies with diet and development. We show that Drosophila can produce four different classes of ecdysteroids, which are obligatorily derived from four types of dietary sterol precursors. Drosophila makes makisterone A from plant sterols and epi-makisterone A from ergosterol, the major yeast sterol. However, they prefer to selectively utilize scarce ergosterol precursors to make a novel hormone 24,28-dehydromakisterone A and trace cholesterol to synthesize 20-hydroxyecdysone. Interestingly, epi-makisterone A supports only larval development, whereas all other ecdysteroids allow full adult development. We suggest that evolutionary pressure against producing epi-C-24 ecdysteroids might explain selective utilization of ergosterol precursors and the puzzling preference for cholesterol.
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Affiliation(s)
- Oksana Lavrynenko
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
| | - Jonathan Rodenfels
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
| | - Maria Carvalho
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
| | - Natalie A Dye
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
| | - Rene Lafont
- Sorbonne Universités, University Pierre and Marie Curie, Paris 06, IBPS-BIOSIPE, 7 Quai Saint Bernard, Case Courrier 29, Paris Cedex 05 75252, France
| | - Suzanne Eaton
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
| | - Andrej Shevchenko
- Max Planck Institute for Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden 01307, Germany
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Dunst S, Kazimiers T, von Zadow F, Jambor H, Sagner A, Brankatschk B, Mahmoud A, Spannl S, Tomancak P, Eaton S, Brankatschk M. Endogenously tagged rab proteins: a resource to study membrane trafficking in Drosophila. Dev Cell 2015; 33:351-65. [PMID: 25942626 PMCID: PMC4431667 DOI: 10.1016/j.devcel.2015.03.022] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/21/2015] [Accepted: 03/29/2015] [Indexed: 11/25/2022]
Abstract
Membrane trafficking is key to the cell biological mechanisms underlying development. Rab GTPases control specific membrane compartments, from core secretory and endocytic machinery to less-well-understood compartments. We tagged all 27 Drosophila Rabs with YFP(MYC) at their endogenous chromosomal loci, determined their expression and subcellular localization in six tissues comprising 23 cell types, and provide this data in an annotated, searchable image database. We demonstrate the utility of these lines for controlled knockdown and show that similar subcellular localization can predict redundant functions. We exploit this comprehensive resource to ask whether a common Rab compartment architecture underlies epithelial polarity. Strikingly, no single arrangement of Rabs characterizes the five epithelia we examine. Rather, epithelia flexibly polarize Rab distribution, producing membrane trafficking architectures that are tissue- and stage-specific. Thus, the core machinery responsible for epithelial polarization is unlikely to rely on polarized positioning of specific Rab compartments.
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Affiliation(s)
- Sebastian Dunst
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Tom Kazimiers
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; HHMI Janelia Research Campus, Ashburn, VA 20147, USA
| | - Felix von Zadow
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Helena Jambor
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Andreas Sagner
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; MRC National Institute for Medical Research, London NW7 1AA, UK
| | - Beate Brankatschk
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany; Paul Langerhans Institute, Dresden 01307, Germany
| | - Ali Mahmoud
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Stephanie Spannl
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Pavel Tomancak
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
| | - Suzanne Eaton
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
| | - Marko Brankatschk
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany.
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Garlapow ME, Huang W, Yarboro MT, Peterson KR, Mackay TFC. Quantitative Genetics of Food Intake in Drosophila melanogaster. PLoS One 2015; 10:e0138129. [PMID: 26375667 PMCID: PMC4574202 DOI: 10.1371/journal.pone.0138129] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 08/25/2015] [Indexed: 12/16/2022] Open
Abstract
Food intake is an essential animal activity, regulated by neural circuits that motivate food localization, evaluate nutritional content and acceptance or rejection responses through the gustatory system, and regulate neuroendocrine feedback loops that maintain energy homeostasis. Excess food consumption in people is associated with obesity and metabolic and cardiovascular disorders. However, little is known about the genetic basis of natural variation in food consumption. To gain insights in evolutionarily conserved genetic principles that regulate food intake, we took advantage of a model system, Drosophila melanogaster, in which food intake, environmental conditions and genetic background can be controlled precisely. We quantified variation in food intake among 182 inbred, sequenced lines of the Drosophila melanogaster Genetic Reference Panel (DGRP). We found significant genetic variation in the mean and within-line environmental variance of food consumption and observed sexual dimorphism and genetic variation in sexual dimorphism for both food intake traits (mean and variance). We performed genome wide association (GWA) analyses for mean food intake and environmental variance of food intake (using the coefficient of environmental variation, CVE, as the metric for environmental variance) and identified molecular polymorphisms associated with both traits. Validation experiments using RNAi-knockdown confirmed 24 of 31 (77%) candidate genes affecting food intake and/or variance of food intake, and a test cross between selected DGRP lines confirmed a SNP affecting mean food intake identified in the GWA analysis. The majority of the validated candidate genes were novel with respect to feeding behavior, and many had mammalian orthologs implicated in metabolic diseases.
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Affiliation(s)
- Megan E. Garlapow
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Wen Huang
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Michael T. Yarboro
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Kara R. Peterson
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Trudy F. C. Mackay
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
- * E-mail:
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Schirmeier S, Matzat T, Klämbt C. Axon ensheathment and metabolic supply by glial cells in Drosophila. Brain Res 2015; 1641:122-129. [PMID: 26367447 DOI: 10.1016/j.brainres.2015.09.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/02/2015] [Accepted: 09/03/2015] [Indexed: 02/06/2023]
Abstract
Neuronal function requires constant working conditions and a well-balanced supply of ions and metabolites. The metabolic homeostasis in the nervous system crucially depends on the presence of glial cells, which nurture and isolate neuronal cells. Here we review recent findings on how these tasks are performed by glial cells in the genetically amenable model organism Drosophila melanogaster. Despite the small size of its nervous system, which would allow diffusion of metabolites, a surprising division of labor between glial cells and neurons is evident. Glial cells are glycolytically active and transfer lactate and alanine to neurons. Neurons in turn do not require glycolysis but can use the glially provided compounds for their energy homeostasis. Besides feeding neurons, glial cells also insulate neuronal axons in a way similar to Remak fibers in the mammalian nervous system. The molecular mechanisms orchestrating this insulation require neuregulin signaling and resemble the mechanisms controlling glial differentiation in mammals surprisingly well. We hypothesize that metabolic cross talk and insulation of neurons by glial cells emerged early during evolution as two closely interlinked features in the nervous system. This article is part of a Special Issue entitled SI: Myelin Evolution.
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Affiliation(s)
- Stefanie Schirmeier
- Institut für Neuro- und Verhaltensbiologie, Badestr. 9, 48149 Münster, Germany
| | - Till Matzat
- Institut für Neuro- und Verhaltensbiologie, Badestr. 9, 48149 Münster, Germany
| | - Christian Klämbt
- Institut für Neuro- und Verhaltensbiologie, Badestr. 9, 48149 Münster, Germany.
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Hindle SJ, Bainton RJ. Barrier mechanisms in the Drosophila blood-brain barrier. Front Neurosci 2014; 8:414. [PMID: 25565944 PMCID: PMC4267209 DOI: 10.3389/fnins.2014.00414] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 11/24/2014] [Indexed: 12/12/2022] Open
Abstract
The invertebrate blood-brain barrier (BBB) field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through G-protein coupled receptor signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate BBB has recently been shown to require coordinated function of all layers of the compound barrier structure, analogous to signaling between the layers of the vertebrate neurovascular unit. These findings strengthen the notion that many BBB mechanisms are conserved between vertebrates and invertebrates, and suggest that novel findings in invertebrate model organisms will have a significant impact on the understanding of vertebrate BBB functions. In this vein, important roles in coordinating localized and systemic signaling to dictate organism development and growth are beginning to show how the BBB can govern whole animal physiologies. This includes novel functions of BBB gap junctions in orchestrating synchronized neuroblast proliferation, and of BBB secreted antagonists of insulin receptor signaling. These advancements and others are pushing the field forward in exciting new directions. In this review, we provide a synopsis of invertebrate BBB anatomy and physiology, with a focus on insights from the past 5 years, and highlight important areas for future study.
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Affiliation(s)
- Samantha J Hindle
- Department of Anesthesia and Perioperative Care, University of California, San Francisco San Francisco, CA, USA
| | - Roland J Bainton
- Department of Anesthesia and Perioperative Care, University of California, San Francisco San Francisco, CA, USA
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