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Sun J, Wu J, Zhang X, Wei Q, Kang W, Wang F, Liu F, Zhao M, Xu S, Han B. Enantioselective toxicity of the neonicotinoid dinotefuran on honeybee (Apis mellifera) larvae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 944:174014. [PMID: 38880156 DOI: 10.1016/j.scitotenv.2024.174014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Revised: 06/13/2024] [Accepted: 06/13/2024] [Indexed: 06/18/2024]
Abstract
The threat of neonicotinoids to insect pollinators, particularly honeybees (Apis mellifera), is a global concern, but the risk of chiral neonicotinoids to insect larvae remains poorly understood. In the current study, we evaluated the acute and chronic toxicity of dinotefuran enantiomers to honeybee larvae in vitro and explored the mechanism of toxicity. The results showed that the acute median lethal dose (LD50) of S-dinotefuran to honeybee larvae was 30.0 μg/larva after oral exposure for 72 h, which was more toxic than rac-dinotefuran (92.7 μg/larva) and R-dinotefuran (183.6 μg/larva). Although the acute toxicity of the three forms of dinotefuran to larvae was lower than that to adults, chronic exposure significantly reduced larval survival, larval weight, and weight of newly emerged adults. Analysis of gene expression and hormone titer indicated that dinotefuran affects larval growth and development by interfering with nutrient digestion and absorption and the molting system. Analysis of hemolymph metabolome further revealed that disturbances in the neuroactive ligand-receptor interaction pathway and energy metabolism are the key mechanisms of dinotefuran toxicity to bee larvae. In addition, melatonin and vitellogenin are used by larvae to cope with dinotefuran-induced oxidative stress. Our results contribute to a comprehensive understanding of dinotefuran damage to bees and provide new insights into the mechanism of enantioselective toxicity of insecticides to insect larvae.
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Affiliation(s)
- Jiajing Sun
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Modern Agricultural College, Yibin Vocational and Technical College, Yibin 644100, China
| | - Jiangli Wu
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Xufeng Zhang
- Institute of Horticultural Research, Shanxi Academy of Agricultural Sciences, Shanxi Agricultural University, Taiyuan 030031, China
| | - Qiaohong Wei
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Weipeng Kang
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Feng Wang
- Institute of Horticultural Research, Shanxi Academy of Agricultural Sciences, Shanxi Agricultural University, Taiyuan 030031, China
| | - Fengying Liu
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Meijiao Zhao
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Shufa Xu
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Bin Han
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
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2
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Poe AR, Zhu L, Tang SH, Valencia E, Kayser MS. Energetic Demands Regulate Sleep-Wake Rhythm Circuit Development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.19.558472. [PMID: 37786713 PMCID: PMC10541615 DOI: 10.1101/2023.09.19.558472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
Sleep and feeding patterns lack strong daily rhythms during early life. As diurnal animals mature, feeding is consolidated to the day and sleep to the night. In Drosophila, circadian sleep patterns are initiated with formation of a circuit connecting the central clock to arousal output neurons; emergence of circadian sleep also enables long-term memory (LTM). However, the cues that trigger the development of this clock-arousal circuit are unknown. Here, we identify a role for nutritional status in driving sleep-wake rhythm development in Drosophila larvae. We find that in the 2nd instar larval period (L2), sleep and feeding are spread across the day; these behaviors become organized into daily patterns by the 3rd instar larval stage (L3). Forcing mature (L3) animals to adopt immature (L2) feeding strategies disrupts sleep-wake rhythms and the ability to exhibit LTM. In addition, the development of the clock (DN1a)-arousal (Dh44) circuit itself is influenced by the larval nutritional environment. Finally, we demonstrate that larval arousal Dh44 neurons act through glucose metabolic genes to drive onset of daily sleep-wake rhythms. Together, our data suggest that changes to energetic demands in developing organisms trigger the formation of sleep-circadian circuits and behaviors.
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Affiliation(s)
- Amy R Poe
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lucy Zhu
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Si Hao Tang
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ella Valencia
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew S Kayser
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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3
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Krejčová G, Danielová A, Sehadová H, Dyčka F, Kubásek J, Moos M, Bajgar A. Macrophages play a nutritive role in post-metamorphic maturation in Drosophila. Development 2024; 151:dev202492. [PMID: 38456486 DOI: 10.1242/dev.202492] [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: 11/01/2023] [Accepted: 02/27/2024] [Indexed: 03/09/2024]
Abstract
In the body of multicellular organisms, macrophages play an indispensable role in maintaining tissue homeostasis by removing old, apoptotic and damaged cells. In addition, macrophages allow significant remodeling of body plans during embryonic morphogenesis, regeneration and metamorphosis. Although the huge amount of organic matter that must be removed during these processes represents a potential source of nutrients, their further use by the organism has not yet been addressed. Here, we document that, during metamorphosis, Drosophila larval adipose tissue is infiltrated by macrophages, which remove dying adipocytes by efferocytosis and engulf leaking RNA-protein granules and lipids. Consequently, the infiltrating macrophages transiently adopt the adipocyte-like metabolic profile to convert remnants of dying adipocytes to lipoproteins and storage peptides that nutritionally support post-metamorphic development. This process is fundamental for the full maturation of ovaries and the achievement of early fecundity of individuals. Whether macrophages play an analogous role in other situations of apoptotic cell removal remains to be elucidated.
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Affiliation(s)
- Gabriela Krejčová
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Ceske Budejovice, 37005, Czech Republic
| | - Adéla Danielová
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Ceske Budejovice, 37005, Czech Republic
| | - Hana Sehadová
- Institute of Entomology , Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, 37005, Czech Republic
| | - Filip Dyčka
- Department of Chemistry, Faculty of Science, University of South Bohemia, Ceske Budejovice, 37005, Czech Republic
| | - Jiří Kubásek
- Department of Experimental Plant Biology, Faculty of Science, University of South Bohemia, Ceske Budejovice, 37005, Czech Republic
| | - Martin Moos
- Institute of Entomology , Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, 37005, Czech Republic
| | - Adam Bajgar
- Department of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Ceske Budejovice, 37005, Czech Republic
- Institute of Entomology , Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, 37005, Czech Republic
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4
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Murakawa T, Nakamura T, Kawaguchi K, Murayama F, Zhao N, Stasevich TJ, Kimura H, Fujita N. A Drosophila toolkit for HA-tagged proteins unveils a block in autophagy flux in the last instar larval fat body. Development 2022; 149:274775. [DOI: 10.1242/dev.200243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/27/2022] [Indexed: 01/18/2023]
Abstract
ABSTRACT
For in vivo functional analysis of a protein of interest (POI), multiple transgenic strains with a POI that harbors different tags are needed but generation of these strains is still labor-intensive work. To overcome this, we have developed a versatile Drosophila toolkit with a genetically encoded single-chain variable fragment for the HA epitope tag: ‘HA Frankenbody’. This system allows various analyses of HA-tagged POI in live tissues by simply crossing an HA Frankenbody fly with an HA-tagged POI fly. Strikingly, the GFP-mCherry tandem fluorescent-tagged HA Frankenbody revealed a block in autophagic flux and an accumulation of enlarged autolysosomes in the last instar larval and prepupal fat body. Mechanistically, lysosomal activity was downregulated at this stage, and endocytosis, but not autophagy, was indispensable for the swelling of lysosomes. Furthermore, forced activation of lysosomes by fat body-targeted overexpression of Mitf, the single MiTF/TFE family gene in Drosophila, suppressed the lysosomal swelling and resulted in pupal lethality. Collectively, we propose that downregulated lysosomal function in the fat body plays a role in the metamorphosis of Drosophila.
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Affiliation(s)
- Tadayoshi Murakawa
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-11 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Tsuyoshi Nakamura
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-11 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Kohei Kawaguchi
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-11 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Futoshi Murayama
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Ning Zhao
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Timothy J. Stasevich
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
- World Research Hub Initiative, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Hiroshi Kimura
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-11 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- World Research Hub Initiative, Tokyo Institute of Technology, Yokohama 226-8503, Japan
| | - Naonobu Fujita
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, 4259-S2-11 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
- Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama 226-8503, Japan
- Precursory Research for Embryonic Science & Technology (PRESTO), Japan Science & Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
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5
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Parra-Peralbo E, Talamillo A, Barrio R. Origin and Development of the Adipose Tissue, a Key Organ in Physiology and Disease. Front Cell Dev Biol 2022; 9:786129. [PMID: 34993199 PMCID: PMC8724577 DOI: 10.3389/fcell.2021.786129] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 12/01/2021] [Indexed: 12/17/2022] Open
Abstract
Adipose tissue is a dynamic organ, well known for its function in energy storage and mobilization according to nutrient availability and body needs, in charge of keeping the energetic balance of the organism. During the last decades, adipose tissue has emerged as the largest endocrine organ in the human body, being able to secrete hormones as well as inflammatory molecules and having an important impact in multiple processes such as adipogenesis, metabolism and chronic inflammation. However, the cellular progenitors, development, homeostasis and metabolism of the different types of adipose tissue are not fully known. During the last decade, Drosophila melanogaster has demonstrated to be an excellent model to tackle some of the open questions in the field of metabolism and development of endocrine/metabolic organs. Discoveries ranged from new hormones regulating obesity to subcellular mechanisms that regulate lipogenesis and lipolysis. Here, we review the available evidences on the development, types and functions of adipose tissue in Drosophila and identify some gaps for future research. This may help to understand the cellular and molecular mechanism underlying the pathophysiology of this fascinating key tissue, contributing to establish this organ as a therapeutic target.
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Affiliation(s)
| | - Ana Talamillo
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Rosa Barrio
- Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Spain
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6
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Meschi E, Delanoue R. Adipokine and fat body in flies: Connecting organs. Mol Cell Endocrinol 2021; 533:111339. [PMID: 34082046 DOI: 10.1016/j.mce.2021.111339] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/21/2021] [Accepted: 05/25/2021] [Indexed: 10/21/2022]
Abstract
Under conditions of nutritional and environmental stress, organismal homeostasis is preserved through inter-communication between multiple organs. To do so, higher organisms have developed a system of interorgan communication through which one tissue can affect the metabolism, activity or fate of remote organs, tissues or cells. In this review, we discuss the latest findings emphasizing Drosophila melanogaster as a powerful model organism to study these interactions and may constitute one of the best documented examples depicting the long-distance communication between organs. In flies, the adipose tissue appears to be one of the main organizing centers for the regulation of insect development and behavior: it senses nutritional and hormonal signals and in turn, orchestrates the release of appropriate adipokines. We discuss the nature and the role of recently uncovered adipokines, their regulations by external cues, their secretory routes and their modes of action to adjust developmental growth and timing accordingly. These findings have the potential for identification of candidate factors and signaling pathways that mediate conserved interorgan crosstalk.
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Affiliation(s)
- Eleonora Meschi
- Centre for Neural Circuit and Behaviour, University of Oxford, Mansfield road, OX3 1SR, Oxford, UK
| | - Renald Delanoue
- University Côte d'Azur, CNRS, Inserm, Institute of Biology Valrose Parc Valrose, 06108, Nice, France.
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7
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Anreiter I, Allen AM, Vasquez OE, To L, Douglas SJ, Alvarez JV, Ewer J, Sokolowski MB. The Drosophila foraging gene plays a vital role at the start of metamorphosis for subsequent adult emergence. J Neurogenet 2021; 35:179-191. [PMID: 33944658 DOI: 10.1080/01677063.2021.1914608] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The foraging (for) gene has been extensively studied in many species for its functions in development, physiology, and behavior. It is common for genes that influence behavior and development to be essential genes, and for has been found to be an essential gene in both fruit flies and mammals, with for mutants dying before reaching the adult stage. However, the biological process underlying the lethality associated with this gene is not known. Here, we show that in Drosophila melanogaster, some but not all gene products of for are essential for survival. Specifically, we show that promoter 3 of for, but not promoters 1, 2, and 4 are required for survival past pupal stage. We use full and partial genetic deletions of for, and temperature-restricted knock-down of the gene to further investigate the stage of lethality. While deletion analysis shows that flies lacking for die at the end of pupal development, as pharate adults, temperature-restricted knock-down shows that for is only required at the start of pupal development, for normal adult emergence (AE) and viability. We further show that the inability of these mutants to emerge from their pupal cases is linked to deficiencies in emergence behaviors, caused by a possible energy deficiency, and finally, that the lethality of for mutants seems to be linked to protein isoform P3, transcribed from for promoter 3.
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Affiliation(s)
- Ina Anreiter
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada.,Child and Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Canada.,Department of Neurobiology, Stanford University, Stanford, CA, USA
| | - Aaron M Allen
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada.,Centre for Neural Circuits and Behavior, University of Oxford, Oxford, UK
| | - Oscar E Vasquez
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Lydia To
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada
| | - Scott J Douglas
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Javier V Alvarez
- Centro Interdisciplinario de Neurociencia de Valparaíso e Instituto de Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - John Ewer
- Centro Interdisciplinario de Neurociencia de Valparaíso e Instituto de Neurociencia, Universidad de Valparaíso, Valparaíso, Chile
| | - Marla B Sokolowski
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Canada.,Child and Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
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8
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Duan X, Tong C. Autophagy in Drosophila and Zebrafish. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1208:333-356. [PMID: 34260032 DOI: 10.1007/978-981-16-2830-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved cellular process that delivers cellular contents to the lysosome for degradation. It not only serves as a bulk degradation system for various cytoplasmic components but also functions selectively to clear damaged organelles, aggregated proteins, and invading pathogens (Feng et al., Cell Res 24:24-41, 2014; Galluzzi et al., EMBO J 36:1811-36, 2017; Klionsky et al., Autophagy 12:1-222, 2016). The malfunction of autophagy leads to multiple developmental defects and diseases (Mizushima et al., Nature 451:1069-75, 2008). Drosophila and zebrafish are higher metazoan model systems with sophisticated genetic tools readily available, which make it possible to dissect the autophagic processes and to understand the physiological functions of autophagy (Lorincz et al., Cells 6:22, 2017a; Mathai et al., Cells 6:21, 2017; Zhang and Baehrecke, Trends Cell Biol 25:376-87, 2015). In this chapter, we will discuss recent progress that has been made in the autophagic field by using these animal models. We will focus on the protein machineries required for autophagosome formation and maturation as well as the physiological roles of autophagy in both Drosophila and zebrafish.
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Affiliation(s)
- Xiuying Duan
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chao Tong
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China. .,The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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9
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The Genetic Basis of Natural Variation in Drosophila melanogaster Immune Defense against Enterococcus faecalis. Genes (Basel) 2020; 11:genes11020234. [PMID: 32098395 PMCID: PMC7074548 DOI: 10.3390/genes11020234] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/18/2020] [Accepted: 02/18/2020] [Indexed: 01/03/2023] Open
Abstract
Dissecting the genetic basis of natural variation in disease response in hosts provides insights into the coevolutionary dynamics of host-pathogen interactions. Here, a genome-wide association study of Drosophila melanogaster survival after infection with the Gram-positive entomopathogenic bacterium Enterococcus faecalis is reported. There was considerable variation in defense against E. faecalis infection among inbred lines of the Drosophila Genetics Reference Panel. We identified single nucleotide polymorphisms associated with six genes with a significant (p < 10-08, corresponding to a false discovery rate of 2.4%) association with survival, none of which were canonical immune genes. To validate the role of these genes in immune defense, their expression was knocked-down using RNAi and survival of infected hosts was followed, which confirmed a role for the genes krishah and S6k in immune defense. We further identified a putative role for the Bomanin gene BomBc1 (also known as IM23), in E. faecalis infection response. This study adds to the growing set of association studies for infection in Drosophila melanogaster and suggests that the genetic causes of variation in immune defense differ for different pathogens.
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10
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Xie L, Gu X, Okamoto K, Westermark GT, Leifer K. 3D analysis of human islet amyloid polypeptide crystalline structures in Drosophila melanogaster. PLoS One 2019; 14:e0223456. [PMID: 31600260 PMCID: PMC6786548 DOI: 10.1371/journal.pone.0223456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 09/20/2019] [Indexed: 11/18/2022] Open
Abstract
Expression of the Alzheimer’s disease associated polypeptide Aβ42 and the human polypeptide hormon islet amyloid polypeptide (hIAPP) and the prohormone precursor (hproIAPP) in neurons of Drosophila melanogaster leads to the formation of protein aggregates in the fat body tissue surrounding the brain. We determined the structure of these membrane-encircled protein aggregates using transmission electron microscopy (TEM) and observed the dissolution of protein aggregates after starvation. Electron tomography (ET) as an extension of transmission electron microscopy revealed that these aggregates were comprised of granular subunits having a diameter of 20 nm aligned into highly ordered structures in all three dimensions. The three dimensional (3D) lattice of hIAPP granules were constructed of two unit cells, a body centered tetragonal (BCT) and a triclinic unit cell. A 5-fold twinned structure was observed consisting of the cyclic twinning of the BCT and triclinic unit cells. The interaction between the two nearest hIAPP granules in both unit cells is not only governed by the van der Waals forces and the dipole-dipole interaction but potentially also by filament-like structures that can connect the nearest neighbors. Hence, our 3D structural analysis provides novel insight into the aggregation process of hIAPP in the fat body tissue of Drosophila melanogaster.
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Affiliation(s)
- Ling Xie
- Department of Engineering Sciences, Applied Materials Sciences, Uppsala University, Uppsala, Sweden
| | - Xiaohong Gu
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Kenta Okamoto
- Department of Biology Physics, Uppsala University, Uppsala, Sweden
| | - Gunilla T. Westermark
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- * E-mail: (KL); (GTW)
| | - Klaus Leifer
- Department of Engineering Sciences, Applied Materials Sciences, Uppsala University, Uppsala, Sweden
- * E-mail: (KL); (GTW)
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11
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Maruzs T, Simon-Vecsei Z, Kiss V, Csizmadia T, Juhász G. On the Fly: Recent Progress on Autophagy and Aging in Drosophila. Front Cell Dev Biol 2019; 7:140. [PMID: 31396511 PMCID: PMC6667644 DOI: 10.3389/fcell.2019.00140] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/09/2019] [Indexed: 01/03/2023] Open
Abstract
Autophagy ensures the lysosome-mediated breakdown and recycling of self-material, as it not only degrades obsolete or damaged intracellular constituents but also provides building blocks for biosynthetic and energy producing reactions. Studies in animal models including Drosophila revealed that autophagy defects lead to the rapid decline of neuromuscular function, neurodegeneration, sensitivity to stress (such as starvation or oxidative damage), and stem cell loss. Of note, recently identified human Atg gene mutations cause similar symptoms including ataxia and mental retardation. Physiologically, autophagic degradation (flux) is known to decrease during aging, and this defect likely contributes to the development of such age-associated diseases. Many manipulations that extend lifespan (including dietary restriction, reduced TOR kinase signaling, exercise or treatment with various anti-aging substances) require autophagy for their beneficial effect on longevity, pointing to the key role of this housekeeping process. Importantly, genetic (e.g., Atg8a overexpression in either neurons or muscle) or pharmacological (e.g., feeding rapamycin or spermidine to animals) promotion of autophagy has been successfully used to extend lifespan in Drosophila, suggesting that this intracellular degradation pathway can rejuvenate cells and organisms. In this review, we highlight key discoveries and recent progress in understanding the relationship of autophagy and aging in Drosophila.
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Affiliation(s)
- Tamás Maruzs
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Zsófia Simon-Vecsei
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Viktória Kiss
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary
| | - Tamás Csizmadia
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
| | - Gábor Juhász
- Institute of Genetics, Biological Research Centre of the Hungarian Academy of Sciences, Szeged, Hungary.,Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary
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12
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Jovanović B, Jovanović N, Cvetković VJ, Matić S, Stanić S, Whitley EM, Mitrović TL. The effects of a human food additive, titanium dioxide nanoparticles E171, on Drosophila melanogaster - a 20 generation dietary exposure experiment. Sci Rep 2018; 8:17922. [PMID: 30560898 PMCID: PMC6298969 DOI: 10.1038/s41598-018-36174-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 10/26/2018] [Indexed: 01/03/2023] Open
Abstract
In this study, fruit flies (Drosophila melanogaster) were exposed to an estimated daily human E171 consumption concentration for 20 generations. Exposure to E171 resulted in: a change in normal developmental and reproductive dynamics, reduced fecundity after repetitive breeding, increased genotoxicity, the appearance of aberrant phenotypes and morphologic changes to the adult fat body. Marks of adaptive evolution and directional selection were also exhibited. The larval stages were at a higher risk of sustaining damage from E171 as they had a slower elimination rate of TiO2 compared to the adults. This is particularly worrisome, since among the human population, children tend to consume higher daily concentrations of E171 than do adults. The genotoxic effect of E171 was statistically higher in each subsequent generation compared to the previous one. Aberrant phenotypes were likely caused by developmental defects induced by E171, and were not mutations, since the phenotypic features were not transferred to any progeny even after 5 generations of consecutive crossbreeding. Therefore, exposure to E171 during the early developmental period carries a higher risk of toxicity. The fact that the daily human consumption concentration of E171 interferes with and influences fruit fly physiological, ontogenetic, genotoxic, and adaptive processes certainly raises safety concerns.
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Affiliation(s)
- Boris Jovanović
- Department of Natural Resource Ecology and Management, Iowa State University, Ames, IA, USA.
| | - Nikola Jovanović
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
| | - Vladimir J Cvetković
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
| | - Sanja Matić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Kragujevac, Serbia
| | - Snežana Stanić
- Department of Biology and Ecology, Faculty of Science, University of Kragujevac, Kragujevac, Serbia
| | | | - Tatjana Lj Mitrović
- Department of Biology and Ecology, Faculty of Sciences and Mathematics, University of Niš, Niš, Serbia
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13
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Lőrincz P, Mauvezin C, Juhász G. Exploring Autophagy in Drosophila. Cells 2017; 6:cells6030022. [PMID: 28704946 PMCID: PMC5617968 DOI: 10.3390/cells6030022] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 07/06/2017] [Accepted: 07/08/2017] [Indexed: 12/11/2022] Open
Abstract
Autophagy is a catabolic process in eukaryotic cells promoting bulk or selective degradation of cellular components within lysosomes. In recent decades, several model systems were utilized to dissect the molecular machinery of autophagy and to identify the impact of this cellular “self-eating” process on various physiological and pathological processes. Here we briefly discuss the advantages and limitations of using the fruit fly Drosophila melanogaster, a popular model in cell and developmental biology, to apprehend the main pathway of autophagy in a complete animal.
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Affiliation(s)
- Péter Lőrincz
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, H-1117 Budapest, Hungary.
| | - Caroline Mauvezin
- Catalan Institute of Oncology-IDIBELL, Laboratory of Cancer Metabolism (LMC), Hospital Duran i Reynals, 08908 Barcelona, Spain.
| | - Gábor Juhász
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, H-1117 Budapest, Hungary.
- Institute of Genetics, Biological Research Centre, Hungarian Academy of Sciences, H-6726 Szeged, Hungary.
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14
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Zheng H, Yang X, Xi Y. Fat body remodeling and homeostasis control in Drosophila. Life Sci 2016; 167:22-31. [DOI: 10.1016/j.lfs.2016.10.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/14/2016] [Accepted: 10/16/2016] [Indexed: 11/29/2022]
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15
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Insulin and TOR signal in parallel through FOXO and S6K to promote epithelial wound healing. Nat Commun 2016; 7:12972. [PMID: 27713427 PMCID: PMC5059774 DOI: 10.1038/ncomms12972] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 08/22/2016] [Indexed: 12/18/2022] Open
Abstract
The TOR and Insulin/IGF signalling (IIS) network controls growth, metabolism and ageing. Although reducing TOR or insulin signalling can be beneficial for ageing, it can be detrimental for wound healing, but the reasons for this difference are unknown. Here we show that IIS is activated in the cells surrounding an epidermal wound in Drosophila melanogaster larvae, resulting in PI3K activation and redistribution of the transcription factor FOXO. Insulin and TOR signalling are independently necessary for normal wound healing, with FOXO and S6K as their respective effectors. IIS is specifically required in cells surrounding the wound, and the effect is independent of glycogen metabolism. Insulin signalling is needed for the efficient assembly of an actomyosin cable around the wound, and constitutively active myosin II regulatory light chain suppresses the effects of reduced IIS. These findings may have implications for the role of insulin signalling and FOXO activation in diabetic wound healing.
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16
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Bader CA, Shandala T, Carter EA, Ivask A, Guinan T, Hickey SM, Werrett MV, Wright PJ, Simpson PV, Stagni S, Voelcker NH, Lay PA, Massi M, Plush SE, Brooks DA. A Molecular Probe for the Detection of Polar Lipids in Live Cells. PLoS One 2016; 11:e0161557. [PMID: 27551717 PMCID: PMC4994960 DOI: 10.1371/journal.pone.0161557] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 08/07/2016] [Indexed: 01/08/2023] Open
Abstract
Lipids have an important role in many aspects of cell biology, including membrane architecture/compartment formation, intracellular traffic, signalling, hormone regulation, inflammation, energy storage and metabolism. Lipid biology is therefore integrally involved in major human diseases, including metabolic disorders, neurodegenerative diseases, obesity, heart disease, immune disorders and cancers, which commonly display altered lipid transport and metabolism. However, the investigation of these important cellular processes has been limited by the availability of specific tools to visualise lipids in live cells. Here we describe the potential for ReZolve-L1™ to localise to intracellular compartments containing polar lipids, such as for example sphingomyelin and phosphatidylethanolamine. In live Drosophila fat body tissue from third instar larvae, ReZolve-L1™ interacted mainly with lipid droplets, including the core region of these organelles. The presence of polar lipids in the core of these lipid droplets was confirmed by Raman mapping and while this was consistent with the distribution of ReZolve-L1™ it did not exclude that the molecular probe might be detecting other lipid species. In response to complete starvation conditions, ReZolve-L1™ was detected mainly in Atg8-GFP autophagic compartments, and showed reduced staining in the lipid droplets of fat body cells. The induction of autophagy by Tor inhibition also increased ReZolve-L1™ detection in autophagic compartments, whereas Atg9 knock down impaired autophagosome formation and altered the distribution of ReZolve-L1™. Finally, during Drosophila metamorphosis fat body tissues showed increased ReZolve-L1™ staining in autophagic compartments at two hours post puparium formation, when compared to earlier developmental time points. We concluded that ReZolve-L1™ is a new live cell imaging tool, which can be used as an imaging reagent for the detection of polar lipids in different intracellular compartments.
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Affiliation(s)
- Christie A. Bader
- School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia, Australia
| | - Tetyana Shandala
- School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia, Australia
| | - Elizabeth A. Carter
- Vibrational Spectroscopy Core Facility, The University of Sydney, Sydney, New South Wales, Australia
| | - Angela Ivask
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Taryn Guinan
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Shane M. Hickey
- School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia, Australia
| | - Melissa V. Werrett
- Department of Chemistry and Nanochemistry Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Phillip J. Wright
- Department of Chemistry and Nanochemistry Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Peter V. Simpson
- Department of Chemistry and Nanochemistry Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Stefano Stagni
- Department of Industrial Chemistry “Toso Montanari”, University of Bologna, Bologna, Italy
| | - Nicolas H. Voelcker
- Future Industries Institute, University of South Australia, Mawson Lakes, South Australia, Australia
| | - Peter A. Lay
- Vibrational Spectroscopy Core Facility, The University of Sydney, Sydney, New South Wales, Australia
| | - Massimiliano Massi
- Department of Chemistry and Nanochemistry Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Sally E. Plush
- School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia, Australia
| | - Douglas A. Brooks
- School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia, Australia
- * E-mail:
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17
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Mukherjee A, Patel B, Koga H, Cuervo AM, Jenny A. Selective endosomal microautophagy is starvation-inducible in Drosophila. Autophagy 2016; 12:1984-1999. [PMID: 27487474 DOI: 10.1080/15548627.2016.1208887] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Autophagy delivers cytosolic components to lysosomes for degradation and is thus essential for cellular homeostasis and to cope with different stressors. As such, autophagy counteracts various human diseases and its reduction leads to aging-like phenotypes. Macroautophagy (MA) can selectively degrade organelles or aggregated proteins, whereas selective degradation of single proteins has only been described for chaperone-mediated autophagy (CMA) and endosomal microautophagy (eMI). These 2 autophagic pathways are specific for proteins containing KFERQ-related targeting motifs. Using a KFERQ-tagged fluorescent biosensor, we have identified an eMI-like pathway in Drosophila melanogaster. We show that this biosensor localizes to late endosomes and lysosomes upon prolonged starvation in a KFERQ- and Hsc70-4- dependent manner. Furthermore, fly eMI requires endosomal multivesicular body formation mediated by ESCRT complex components. Importantly, induction of Drosophila eMI requires longer starvation than the induction of MA and is independent of the critical MA genes atg5, atg7, and atg12. Furthermore, inhibition of Tor signaling induces eMI in flies under nutrient rich conditions, and, as eMI in Drosophila also requires atg1 and atg13, our data suggest that these genes may have a novel, additional role in regulating eMI in flies. Overall, our data provide the first evidence for a novel, starvation-inducible, catabolic process resembling endosomal microautophagy in the Drosophila fat body.
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Affiliation(s)
- Anindita Mukherjee
- a Department of Developmental and Molecular Biology , Albert Einstein College of Medicine , New York , NY , USA
| | - Bindi Patel
- a Department of Developmental and Molecular Biology , Albert Einstein College of Medicine , New York , NY , USA
| | - Hiroshi Koga
- a Department of Developmental and Molecular Biology , Albert Einstein College of Medicine , New York , NY , USA
| | - Ana Maria Cuervo
- a Department of Developmental and Molecular Biology , Albert Einstein College of Medicine , New York , NY , USA.,b Institute for Aging Studies, Albert Einstein College of Medicine , New York , NY , USA.,c Marion Bessin Liver Research Center, Albert Einstein College of Medicine , New York , NY , USA
| | - Andreas Jenny
- a Department of Developmental and Molecular Biology , Albert Einstein College of Medicine , New York , NY , USA.,b Institute for Aging Studies, Albert Einstein College of Medicine , New York , NY , USA.,c Marion Bessin Liver Research Center, Albert Einstein College of Medicine , New York , NY , USA.,d Department of Genetics , Albert Einstein College of Medicine , New York , NY , USA
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18
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Fischer P, Preiss A, Nagel AC. A triangular connection between Cyclin G, PP2A and Akt1 in the regulation of growth and metabolism in Drosophila. Fly (Austin) 2016; 10:11-8. [PMID: 26980713 PMCID: PMC4934794 DOI: 10.1080/19336934.2016.1162362] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Size and weight control is a tightly regulated process, involving the highly conserved Insulin receptor/target of rapamycin (InR/TOR) signaling cascade. We recently identified Cyclin G (CycG) as an important modulator of InR/TOR signaling activity in Drosophila. cycG mutant flies are underweight and show a disturbed fat metabolism resembling TOR mutants. In fact, InR/TOR signaling activity is disturbed in cycG mutants at the level of Akt1, the central kinase linking InR and TORC1. Akt1 is negatively regulated by protein phosphatase PP2A. Notably the binding of the PP2A B′-regulatory subunit Widerborst (Wdb) to Akt1 is differentially regulated in cycG mutants, presumably by a direct interaction of CycG and Wdb. Since the metabolic defects of cycG mutant animals are abrogated by a concomitant loss of Wdb, CycG presumably influences Akt1 activity at the PP2A nexus. Here we show that Well rounded (Wrd), another B' subunit of PP2A in Drosophila, binds CycG similar to Wdb, and that its loss ameliorates some, but not all, of the metabolic defects of cycG mutants. We propose a model, whereby the binding of CycG to a particular B′-regulatory subunit influences the tissue specific activity of PP2A, required for the fine tuning of the InR/TOR signaling cascade in Drosophila.
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Affiliation(s)
- Patrick Fischer
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
| | - Anette Preiss
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
| | - Anja C Nagel
- a Institute of Genetics, University of Hohenheim , Stuttgart , Germany
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19
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Bader CA, Shandala T, Ng YS, Johnson IRD, Brooks DA. Atg9 is required for intraluminal vesicles in amphisomes and autolysosomes. Biol Open 2015; 4:1345-55. [PMID: 26353861 PMCID: PMC4728360 DOI: 10.1242/bio.013979] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Autophagy is an intracellular recycling and degradation process, which is important for energy metabolism, lipid metabolism, physiological stress response and organism development. During Drosophila development, autophagy is up-regulated in fat body and midgut cells, to control metabolic function and to enable tissue remodelling. Atg9 is the only transmembrane protein involved in the core autophagy machinery and is thought to have a role in autophagosome formation. During Drosophila development, Atg9 co-located with Atg8 autophagosomes, Rab11 endosomes and Lamp1 endosomes-lysosomes. RNAi silencing of Atg9 reduced both the number and the size of autophagosomes during development and caused morphological changes to amphisomes/autolysosomes. In control cells there was compartmentalised acidification corresponding to intraluminal Rab11/Lamp-1 vesicles, but in Atg9 depleted cells there were no intraluminal vesicles and the acidification was not compartmentalised. We concluded that Atg9 is required to form intraluminal vesicles and for localised acidification within amphisomes/autolysosomes, and consequently when depleted, reduced the capacity to degrade and remodel gut tissue during development. Summary: The disappearance of intraluminal vesicles in amphisomes/autolysosomes upon Atg9 depletion suggests that Atg9 has a specific role in intraluminal vesicle formation in autophagic compartments.
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Affiliation(s)
- C A Bader
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
| | - T Shandala
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
| | - Y S Ng
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
| | - I R D Johnson
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
| | - D A Brooks
- Mechanisms in Cell Biology and Diseases Research Group, School of Pharmacy and Medical Science, University of South Australia, Adelaide, South Australia 5001, Australia
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20
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Mulakkal NC, Nagy P, Takats S, Tusco R, Juhász G, Nezis IP. Autophagy in Drosophila: from historical studies to current knowledge. BIOMED RESEARCH INTERNATIONAL 2014; 2014:273473. [PMID: 24949430 PMCID: PMC4052151 DOI: 10.1155/2014/273473] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 04/17/2014] [Indexed: 12/17/2022]
Abstract
The discovery of evolutionarily conserved Atg genes required for autophagy in yeast truly revolutionized this research field and made it possible to carry out functional studies on model organisms. Insects including Drosophila are classical and still popular models to study autophagy, starting from the 1960s. This review aims to summarize past achievements and our current knowledge about the role and regulation of autophagy in Drosophila, with an outlook to yeast and mammals. The basic mechanisms of autophagy in fruit fly cells appear to be quite similar to other eukaryotes, and the role that this lysosomal self-degradation process plays in Drosophila models of various diseases already made it possible to recognize certain aspects of human pathologies. Future studies in this complete animal hold great promise for the better understanding of such processes and may also help finding new research avenues for the treatment of disorders with misregulated autophagy.
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Affiliation(s)
- Nitha C. Mulakkal
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Peter Nagy
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest H-1117, Hungary
| | - Szabolcs Takats
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest H-1117, Hungary
| | - Radu Tusco
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Gábor Juhász
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest H-1117, Hungary
| | - Ioannis P. Nezis
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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21
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Argue KJ, Neckameyer WS. Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses. Am J Physiol Regul Integr Comp Physiol 2014; 307:R82-92. [PMID: 24789992 DOI: 10.1152/ajpregu.00003.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses.
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Affiliation(s)
- Kathryn J Argue
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri
| | - Wendi S Neckameyer
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri
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22
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Liu H, Jia Q, Tettamanti G, Li S. Balancing crosstalk between 20-hydroxyecdysone-induced autophagy and caspase activity in the fat body during Drosophila larval-prepupal transition. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:1068-1078. [PMID: 24036278 DOI: 10.1016/j.ibmb.2013.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/22/2013] [Accepted: 09/02/2013] [Indexed: 06/02/2023]
Abstract
In the fruitfly, Drosophila melanogaster, autophagy and caspase activity function in parallel in the salivary gland during metamorphosis and in a common regulatory hierarchy during oogenesis. Both autophagy and caspase activity progressively increase in the remodeling fat body, and they are induced by a pulse of the molting hormone (20-hydroxyecdysone, 20E) during the larval-prepupal transition. Inhibition of autophagy and/or caspase activity in the remodeling fat body results in 25-40% pupal lethality, depending on the genotypes. Interestingly, a balancing crosstalk occurs between autophagy and caspase activity in this tissue: the inhibition of autophagy induces caspase activity and the inhibition of caspases induces autophagy. The Drosophila remodeling fat body provides an in vivo model for understanding the molecular mechanism of the balancing crosstalk between autophagy and caspase activity, which oppose with each other and are induced by the common stimulus 20E, and blockage of either path reinforces the other path.
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Affiliation(s)
- Hanhan Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China
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23
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Tian L, Ma L, Guo E, Deng X, Ma S, Xia Q, Cao Y, Li S. 20-Hydroxyecdysone upregulates Atg genes to induce autophagy in the Bombyx fat body. Autophagy 2013; 9:1172-87. [PMID: 23674061 DOI: 10.4161/auto.24731] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Autophagy is finely regulated at multiple levels and plays crucial roles in development and disease. In the fat body of the silkworm, Bombyx mori, autophagy occurs and Atg gene expression peaks during the nonfeeding molting and pupation stages when the steroid hormone (20-hydroxyecdysone; 20E) is high. Injection of 20E into the feeding larvae upregulated Atg genes and reduced TORC1 activity resulting in autophagy induction in the fat body. Conversely, RNAi knockdown of the 20E receptor partner (USP) or targeted overexpression of a dominant negative mutant of the 20E receptor (EcR (DN) ) in the larval fat body reduced autophagy and downregulated the Atg genes, confirming the importance of 20E-induction of Atg gene expression during pupation. Moreover, in vitro treatments of the larval fat body with 20E upregulated the Atg genes. Five Atg genes were potentially 20E primary-responsive, and a 20E response element was identified in the Atg1 (ortholog of human ULK1) promoter region. Furthermore, RNAi knockdown of 4 key genes (namely Br-C, E74, HR3 and βftz-F1) in the 20E-triggered transcriptional cascade reduced autophagy and downregulated Atg genes to different levels. Taken together, we conclude that in addition to blocking TORC1 activity for autophagosome initiation, 20E upregulates Atg genes to induce autophagy in the Bombyx fat body.
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Affiliation(s)
- Ling Tian
- 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; State Key Laboratory of Silkworm Genome Biology; Southwest University; Chongqing, China
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24
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25
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Bolukbasi E, Vass S, Cobbe N, Nelson B, Simossis V, Dunbar DR, Heck MMS. Drosophila poly suggests a novel role for the Elongator complex in insulin receptor-target of rapamycin signalling. Open Biol 2012; 2:110031. [PMID: 22645656 PMCID: PMC3352090 DOI: 10.1098/rsob.110031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 12/21/2011] [Indexed: 01/06/2023] Open
Abstract
Multi-cellular organisms need to successfully link cell growth and metabolism to environmental cues during development. Insulin receptor-target of rapamycin (InR-TOR) signalling is a highly conserved pathway that mediates this link. Herein, we describe poly, an essential gene in Drosophila that mediates InR-TOR signalling. Loss of poly results in lethality at the third instar larval stage, but only after a stage of extreme larval longevity. Analysis in Drosophila demonstrates that Poly and InR interact and that poly mutants show an overall decrease in InR-TOR signalling, as evidenced by decreased phosphorylation of Akt, S6K and 4E-BP. Metabolism is altered in poly mutants, as revealed by microarray expression analysis and a decreased triglyceride : protein ratio in mutant animals. Intriguingly, the cellular distribution of Poly is dependent on insulin stimulation in both Drosophila and human cells, moving to the nucleus with insulin treatment, consistent with a role in InR-TOR signalling. Together, these data reveal that Poly is a novel, conserved (from flies to humans) mediator of InR signalling that promotes an increase in cell growth and metabolism. Furthermore, homology to small subunits of Elongator demonstrates a novel, unexpected role for this complex in insulin signalling.
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Affiliation(s)
| | | | | | | | | | | | - Margarete M. S. Heck
- University of Edinburgh, Queen's Medical
Research Institute, University/BHF Centre for
Cardiovascular Science, 47 Little France Crescent, Edinburgh EH16
4TJ, UK
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26
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Kühnlein RP. The contribution of the Drosophila model to lipid droplet research. Prog Lipid Res 2011; 50:348-56. [DOI: 10.1016/j.plipres.2011.04.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 04/20/2011] [Accepted: 04/28/2011] [Indexed: 12/18/2022]
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27
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Martins GF, Serrão JE, Ramalho-Ortigão JM, Pimenta PFP. Histochemical and ultrastructural studies of the mosquito Aedes aegypti fat body: effects of aging and diet type. Microsc Res Tech 2011; 74:1032-9. [PMID: 21509905 DOI: 10.1002/jemt.20990] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 12/29/2010] [Indexed: 11/09/2022]
Abstract
Aedes aegypti is the principal vector of dengue world wide and a major vector of urban yellow fever. Despite its epidemiological importance, not much is known regarding cellular and structural changes in the fat body in this mosquito. Here, we applied light and transmission electron microscopies to investigate structural changes in the fat body of three groups of A. aegypti females: newly emerged, 18-day-old sugar-fed, and 18-day-old blood-fed. The fat body consists of a layer of cells attached to the abdomen integument, formed by trophocytes and oenocytes. Trophocytes are strongly positive for carbohydrates, while oenocytes are strongly positive for proteins and lipids. Ultrastructural analyses of trophocytes from newly emerged and 18-day-old blood-fed indicate that these cells are rich in glycogen and free ribosomes. Many lipid droplets and protein granules, which are broken down after the blood meal, are also detected. In 18-day-old sugar-fed, trophocytes display a disorganized cytoplasm filled with lipid droplets, and reduced numbers of free ribosomes, glycogen, rough endoplasmic reticulum (RER) and mitochondria. Following a blood meal, the RER and mitochondria display enlarged sizes, suggestive of increased activity. With regard to oenocytes, these cells display an electron-dense cytoplasm and plasma membrane infoldings facing the hemolymph. As the A. aegypti female ages, trophocyte and oenocyte cell nuclei become larger but decrease in diameter after blood feeding. Our findings suggest that the trophocytes and oenocytes remodeling is likely involved in functional changes of fat body that take place during aging and following a blood meal in A. aegypti females.
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Affiliation(s)
- Gustavo Ferreira Martins
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais, Brazil 36570-000.
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28
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The nuclear cofactor DOR regulates autophagy in mammalian and Drosophila cells. EMBO Rep 2009; 11:37-44. [PMID: 20010805 DOI: 10.1038/embor.2009.242] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 10/05/2009] [Accepted: 10/13/2009] [Indexed: 01/17/2023] Open
Abstract
The regulation of autophagy in metazoans is only partly understood, and there is a need to identify the proteins that control this process. The diabetes- and obesity-regulated gene (DOR), a recently reported nuclear cofactor of thyroid hormone receptors, is expressed abundantly in metabolically active tissues such as muscle. Here, we show that DOR shuttles between the nucleus and the cytoplasm, depending on cellular stress conditions, and re-localizes to autophagosomes on autophagy activation. We demonstrate that DOR interacts physically with autophagic proteins Golgi-associated ATPase enhancer of 16 kDa (GATE16) and microtubule-associated protein 1A/1B-light chain 3. Gain-of-function and loss-of-function studies indicate that DOR stimulates autophagosome formation and accelerates the degradation of stable proteins. CG11347, the DOR Drosophila homologue, has been predicted to interact with the Drosophila Atg8 homologues, which suggests functional conservation in autophagy. Flies lacking CG11347 show reduced autophagy in the fat body during pupal development. All together, our data indicate that DOR regulates autophagosome formation and protein degradation in mammalian and Drosophila cells.
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29
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Wu H, Wang MC, Bohmann D. JNK protects Drosophila from oxidative stress by trancriptionally activating autophagy. Mech Dev 2009; 126:624-37. [PMID: 19540338 DOI: 10.1016/j.mod.2009.06.1082] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Revised: 05/17/2009] [Accepted: 06/15/2009] [Indexed: 12/11/2022]
Abstract
JNK signaling functions to induce defense mechanisms that protect organisms against acute oxidative and xenobiotic insults. Using Drosophila as a model system, we investigated the role of autophagy as such a JNK-regulated protective mechanism. We show that oxidative stress can induce autophagy in the intestinal epithelium by a mechanism that requires JNK signaling. Consistently, artificial activation of JNK in the gut gives rise to an autophagy phenotype. JNK signaling can induce the expression of several autophagy-related (ATG) genes, and the integrity of these genes is required for the stress protective function of the JNK pathway. In contrast to autophagy induced by oxidative stress, non-stress related autophagy, as it occurs for example in starving adipose or intestinal tissue, or during metamorphosis, proceeds independently of JNK signaling. Autophagy thus emerges as a multifunctional process that organisms employ in a variety of different situations using separate regulatory mechanisms.
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Affiliation(s)
- Hai Wu
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642, USA
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30
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Nanda S, DeFalco TJ, Loh SHY, Phochanukul N, Camara N, Van Doren M, Russell S. Sox100B, a Drosophila group E Sox-domain gene, is required for somatic testis differentiation. Sex Dev 2009; 3:26-37. [PMID: 19339815 DOI: 10.1159/000200079] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 11/26/2008] [Indexed: 11/19/2022] Open
Abstract
Sex determination mechanisms are thought to evolve rapidly and show little conservation among different animal species. For example, the critical gene on the Y chromosome, SRY, that determines sex in most mammals, is not found in other animals. However, a related Sox domain transcription factor, SOX9, is also required for testis development in mammals and exhibits male-specific gonad expression in other vertebrate species. Previously, we found that the Drosophila orthologue of SOX9, Sox100B, is expressed male-specifically during gonad development. We now investigate the function of Sox100B and find, strikingly, that Sox100B is essential for testis development in Drosophila. In Sox100B mutants, the adult testis is severely reduced and fails to interact with other parts of the reproductive tract, which are themselves unaffected. While a testis initially forms in Sox100B mutants, it fails to undergo proper morphogenesis during pupal stages, likely due to defects in the pigment cells. In contrast, no substantive defects are observed in ovary development in Sox100B mutant females. Thus, as is observed in mammals, a Sox9 homolog is essential for sex-specific gonad development in Drosophila, suggesting that the molecular mechanisms regulating sexually dimorphic gonad development may be more conserved than previously suspected.
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Affiliation(s)
- S Nanda
- Department of Genetics, University of Cambridge, Cambridge, UK
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31
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Schlegel A, Stainier DYR. Lessons from "lower" organisms: what worms, flies, and zebrafish can teach us about human energy metabolism. PLoS Genet 2008; 3:e199. [PMID: 18081423 PMCID: PMC2098794 DOI: 10.1371/journal.pgen.0030199] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A pandemic of metabolic diseases (atherosclerosis, diabetes mellitus, and obesity), unleashed by multiple social and economic factors beyond the control of most individuals, threatens to diminish human life span for the first time in the modern era. Given the redundancy and inherent complexity of processes regulating the uptake, transport, catabolism, and synthesis of nutrients, magic bullets to target these diseases will be hard to find. Recent studies using the worm Caenorhabditis elegans, the fly Drosophila melanogaster, and the zebrafish Danio rerio indicate that these “lower” metazoans possess unique attributes that should help in identifying, investigating, and even validating new pharmaceutical targets for these diseases. We summarize findings in these organisms that shed light on highly conserved pathways of energy homeostasis.
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Affiliation(s)
- Amnon Schlegel
- Department of Biochemistry and Biophysics, Division of Endocrinology at the University of California San Francisco, San Francisco, California, United States of America.
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32
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Juhász G, Puskás LG, Komonyi O, Erdi B, Maróy P, Neufeld TP, Sass M. Gene expression profiling identifies FKBP39 as an inhibitor of autophagy in larval Drosophila fat body. Cell Death Differ 2007; 14:1181-90. [PMID: 17363962 PMCID: PMC2084463 DOI: 10.1038/sj.cdd.4402123] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
In Drosophila, the fat body undergoes a massive burst of autophagy at the end of larval development in preparation for the pupal transition. To identify genes involved in this process, we carried out a microarray analysis. We found that mRNA levels of the homologs of Atg8, the coat protein of early autophagic structures, and lysosomal hydrolases were upregulated, consistent with previous results. Genes encoding mitochondrial proteins and many chaperones were downregulated, including the inhibitor of eIF2alpha kinases and the peptidyl-prolyl cis-trans isomerase FK506-binding protein of 39 kDa (FKBP39). Genetic manipulation of FKBP39 expression had a significant effect on autophagy, potentially through modulation of the transcription factor Foxo. Accordingly, we found that Foxo mutants cannot properly undergo autophagy in response to starvation, and that overexpression of Foxo induces autophagy.
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Affiliation(s)
- G Juhász
- Department of General Zoology, Eötvös Loránd University, Budapest, Hungary.
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33
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Lindmo K, Simonsen A, Brech A, Finley K, Rusten TE, Stenmark H. A dual function for Deep orange in programmed autophagy in the Drosophila melanogaster fat body. Exp Cell Res 2006; 312:2018-27. [PMID: 16600212 DOI: 10.1016/j.yexcr.2006.03.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2005] [Revised: 03/02/2006] [Accepted: 03/06/2006] [Indexed: 12/19/2022]
Abstract
Lysosomal degradation of cytoplasm by way of autophagy is essential for cellular amino acid homeostasis and for tissue remodeling. In insects such as Drosophila, autophagy is developmentally upregulated in the larval fat body prior to metamorphosis. Here, autophagy is induced by the hormone ecdysone through down-regulation of the autophagy-suppressive phosphoinositide 3-kinase (PI3K) signaling pathway. In yeast, Vps18 and other members of the HOPS complex have been found essential for autophagic degradation. In Drosophila, the Vps18 homologue Deep orange (Dor) has previously been shown to mediate fusion of multivesicular endosomes with lysosomes. A requirement of Dor for ecdysone-mediated chromosome puffing has also been reported. In the present report, we have tested the hypothesis that Dor may control programmed autophagy at the level of ecdysone signaling as well as by mediating autophagosome-to-lysosome fusion. We show that dor mutants are defective in programmed autophagy and provide evidence that autophagy is blocked at two levels. First, PI3K activity was not down-regulated correctly in dor larvae, which correlated with a decrease in ecdysone reporter activity. The down-regulation of PI3K activity was restored by feeding ecdysone to the mutant larvae. Second, neither exogenous ecdysone nor overexpression of PTEN, a silencer of PI3K signaling, restored fusion of autophagosomes with lysosomes in the fat body of dor mutants. These results indicate that Dor controls autophagy indirectly, via ecdysone signaling, as well as directly, via autolysosomal fusion.
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Affiliation(s)
- Karine Lindmo
- Department of Biochemistry, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway
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34
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Hosokawa N, Hara Y, Mizushima N. Generation of cell lines with tetracycline-regulated autophagy and a role for autophagy in controlling cell size. FEBS Lett 2006; 580:2623-9. [PMID: 16647067 DOI: 10.1016/j.febslet.2006.04.008] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Revised: 04/03/2006] [Accepted: 04/05/2006] [Indexed: 12/19/2022]
Abstract
Autophagy is an intracellular bulk degradation system. We established mouse fibroblast lines coupling the Tet-off system with an Atg5(-/-) mouse embryonic fibroblast line to artificially regulate autophagic ability. In the presence of doxycycline (Dox), Atg5 expression was completely suppressed and these cells were autophagy-defective. After removal of Dox, autophagic ability was restored within 6h. Very low levels of Atg5 could induce an autophagy competent state. We applied this novel system to examine the contribution of autophagy to controlling cell size. Cell size reduction in response to starvation was significantly inhibited in cells unable to undergo autophagy. The generated cell lines will be useful reagents for future mechanistic studies into the regulation and physiologic significance of autophagy.
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Affiliation(s)
- Nao Hosokawa
- Department of Bioregulation and Metabolism, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Tokyo 113-8613, Japan
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35
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Scott RC, Schuldiner O, Neufeld TP. Role and regulation of starvation-induced autophagy in the Drosophila fat body. Dev Cell 2004; 7:167-78. [PMID: 15296714 DOI: 10.1016/j.devcel.2004.07.009] [Citation(s) in RCA: 744] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2004] [Revised: 06/24/2004] [Accepted: 06/25/2004] [Indexed: 11/16/2022]
Abstract
In response to starvation, eukaryotic cells recover nutrients through autophagy, a lysosomal-mediated process of cytoplasmic degradation. Autophagy is known to be inhibited by TOR signaling, but the mechanisms of autophagy regulation and its role in TOR-mediated cell growth are unclear. Here, we show that signaling through TOR and its upstream regulators PI3K and Rheb is necessary and sufficient to suppress starvation-induced autophagy in the Drosophila fat body. In contrast, TOR's downstream effector S6K promotes rather than suppresses autophagy, suggesting S6K downregulation may limit autophagy during extended starvation. Despite the catabolic potential of autophagy, disruption of conserved components of the autophagic machinery, including ATG1 and ATG5, does not restore growth to TOR mutant cells. Instead, inhibition of autophagy enhances TOR mutant phenotypes, including reduced cell size, growth rate, and survival. Thus, in cells lacking TOR, autophagy plays a protective role that is dominant over its potential role as a growth suppressor.
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Affiliation(s)
- Ryan C Scott
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis 55455 USA
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Rusten TE, Lindmo K, Juhász G, Sass M, Seglen PO, Brech A, Stenmark H. Programmed Autophagy in the Drosophila Fat Body Is Induced by Ecdysone through Regulation of the PI3K Pathway. Dev Cell 2004; 7:179-92. [PMID: 15296715 DOI: 10.1016/j.devcel.2004.07.005] [Citation(s) in RCA: 364] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2004] [Revised: 06/30/2004] [Accepted: 07/06/2004] [Indexed: 10/26/2022]
Abstract
Eukaryotic cells catabolize their own cytoplasm by autophagy in response to amino acid starvation and inductive signals during programmed tissue remodeling and cell death. The Tor and PI3K signaling pathways have been shown to negatively control autophagy in eukaryotes, but the mechanisms that link these effectors to overall animal development and nutritional status in multicellular organisms remain poorly understood. Here, we reveal a complex regulation of programmed and starvation-induced autophagy in the Drosophila fat body. Gain-of-function genetic analysis indicated that ecdysone receptor signaling induces programmed autophagy whereas PI3K signaling represses programmed autophagy. Genetic interaction studies showed that ecdysone signaling downregulates PI3K signaling and that this represents the effector mechanism for induction of programmed autophagy. Hence, these studies link hormonal induction of autophagy to the regulatory function of the PI3K signaling pathway in vivo.
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Affiliation(s)
- Tor Erik Rusten
- Department of Biochemistry, The Norwegian Radium Hospital, Montebello, N-0310 Oslo
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37
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Kosta A, Dimopoulou K, Drosou V, Thomopoulos GN. Glycogen distribution in the larval salivary gland cells during the development of
Drosophila melanogaster
and
Drosophila auraria
: an ultrastructural cytochemical study. J Zool (1987) 2000. [DOI: 10.1111/j.1469-7998.2000.tb00593.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Artemis Kosta
- Aristotle University, School of Sciences, Department of Biology, 540 06 Thessaloniki, Greece
| | - Katerina Dimopoulou
- Aristotle University, School of Sciences, Department of Biology, 540 06 Thessaloniki, Greece
| | - Victoria Drosou
- Aristotle University, School of Sciences, Department of Biology, 540 06 Thessaloniki, Greece
| | - George N. Thomopoulos
- Aristotle University, School of Sciences, Department of Biology, 540 06 Thessaloniki, Greece
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38
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Benes H, Neal KC, Willis RL, Gadde D, Castleberry AB, Korochkina SE. Overlapping Lsp-2 gene sequences target expression to both the larval and adult Drosophila fat body. INSECT MOLECULAR BIOLOGY 1996; 5:39-49. [PMID: 8630534 DOI: 10.1111/j.1365-2583.1996.tb00039.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Larval serum protein-2 gene (Lsp-2) of Drosophila melanogaster encodes one of the major hexameric haemolymph proteins of third-instar larvae and a major component of adult serum. Regulated transcription of Lsp-2 results in high-level, ecdysone-stimulated expression throughout the larval fat body and low-level, spatially restricted expression in the adult fat cells. To localize cis-acting regulatory sequences responsible for the stage- and tissue-specific activity at Lsp-2, the expression of Lsp-2-lacZ fusion genes was studied by P element-mediated germline transformation of Drosophila. A 230 base pair larval enhancer, which includes an ecdysone response element (EcRE), specifically targets gene activity to the larval fat body. Although the adult mode of Lsp-2 expression depends on the larval enhancer, additional negative regulatory elements dictate both tissue-specificity and unique spatial restriction within the adult fat body. Implications of these findings for the identification of fat body-specific gene regulatory units in other insects are discussed.
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Affiliation(s)
- H Benes
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, 72205 , USA
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39
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Abstract
Specific mutations in the yolk protein genes, yp1 and yp2, of Drosophila melanogaster cause the yolk proteins (YPs) they encode to precipitate, ultimately resulting in female sterility. YPs of the yp1 mutant fs(1)1163 are secreted normally but then precipitate as globules and occasionally as crystalline fibers in the subbasement membrane space of the fat body (Butterworth et al., 1991, J. Cell Biol. 112, 727-737). The present ultrastructural and immunological studies of the fat body of the yp2 mutant fs(1)K313 show that YP also precipitates as globules in the same tissue compartment. The globules are also incapable of passing into the hemolymph but they are morphologically distinct from those of fs(1)1163. Similar analyses were performed on developing oocytes in wild type and both mutant strains. YP-containing aggregates, ultrastructurally similar to those in the fat body of each respective mutant, were found in the space between the plasmalemma and the vitelline membrane and embedded within the membrane itself. The evidence suggests that the precipitates interfere with the correct assembly of the eggshell membranes, leading to the sterile phenotype. Immunogold studies demonstrate that newly synthesized YPs in the normal and mutant strains share secretory vesicles with putative, vitelline membrane proteins and that the translocation of follicle cell YP is not through the membrane along the interfollicular spaces but directly through the plasmalemma facing the oocyte. Further the YP precipitates in the mutants permit visualization of the polarity of exocytosis of YP from the follicle cells.
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Affiliation(s)
- F M Butterworth
- Department of Biological Sciences, Oakland University, Rochester, Michigan 48309
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40
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Butterworth FM, Bownes M, Burde VS. Genetically modified yolk proteins precipitate in the adult Drosophila fat body. J Biophys Biochem Cytol 1991; 112:727-37. [PMID: 1899669 PMCID: PMC2288856 DOI: 10.1083/jcb.112.4.727] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Ultrastructural and genetic studies were carried out on the fat body of a female sterile mutant fs(1)1163 to ascertain why yolk protein 1 (YP1) is not secreted from this tissue. Earlier molecular studies demonstrated that (a) normally yolk protein is synthesized in the fat body, secreted into the hemolymph and taken up by the ovary, (b) the 1163 mutation causes a single amino acid substitution in YP1, and (c) females homozygous for the mutation, or heterozygous females raised at 29 degrees C, retain YP1 in the fat body. Ultrastructural analysis in this paper shows that the fat body of these females contains masses of electron-dense material deposited in the subbasement membrane space. This subbasement membrane material (SBMM), which occasionally has a crystalline-like, fibrous component, is found in females whose genotypes include at least one copy of the mutant 1163 gene. These strains include a deletion strain that is hemizygous for the 1163 gene and two strains that are transgenic for the mutant gene. Immunogold studies indicate that SBMM contains yolk protein. We propose that the mutant protein is secreted into the subbasement membrane space, but because of the amino acid substitution in YP1, the oligomers containing YP1 condense into SBMM, which cannot penetrate the basement membrane. The similarity of SBMM and deoxyhemoglobin S fibers is discussed.
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Affiliation(s)
- F M Butterworth
- Department of Biological Sciences, Oakland University, Rochester, Michigan 48309
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41
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Geer BW, Dybas LK, Shanner LJ. Alcohol dehydrogenase and ethanol tolerance at the cellular level in Drosophila melanogaster. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1989; 250:22-39. [PMID: 2498460 DOI: 10.1002/jez.1402500105] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Exposure of early third instar larvae of Drosophila melanogaster to a nonlethal dose of ethanol was detrimental to larvae lacking alcohol dehydrogenase (ADH) but beneficial to wild-type larvae in terms of surviving a later ethanol tolerance test, indicating that one of the important functions of the ADH system is to supply derivatives of ethanol to larvae that in turn promote ethanol tolerance. High intracellular concentrations of ethanol in ADH-deficient (Adhn2) larvae fed ethanol were accompanied by a decrease in the cell membrane infoldings of fat body cells, suggesting that the capacities to absorb and release molecules were reduced. Marked effects of ethanol on the endoplasmic reticulum and mitochondria of ADH-deficient larvae were also evident. The absence of similar changes in wild-type larvae that were fed moderate levels of ethanol showed that the ADH system kept the intracellular level of ethanol at a concentration low enough to avoid cell damage. A cytometric analysis of electron micrographs showed that there were ethanol-induced reductions in glycogen, lipid, and protein stores in the fat body cells of ADH-deficient larvae fed 1.25% ethanol (v/v) compared with null larvae fed an ethanol-free diet. This finding implied that the capacities to synthesize or store these compounds may be limited by high intracellular concentrations of ethanol. The cytometric analysis also revealed that the consumption of diets containing 2.5% and 4.5% ethanol by Canton-S wild-type larvae for 3 days after 4 days of feeding on an ethanol-free diet resulted in decreases in glycogen and protein deposits in fat body cells, but increased the amount of lipid deposits compared to larvae fed an ethanol-free diet. This observation, coupled with the greater weight of wild-type adults that were fed a growth-limiting concentration of ethanol compared with control adults, suggested that a metabolic defense mechanism in larvae is to convert toxic ethanol to nontoxic storage products. Dietary ethanol alone and in combination with isopropanol stimulated an increase in the size of the NAD-pool in larvae, a condition that may favor the activity of ADH. A low dietary level of isopropanol (1%) completely blocked glycogen deposition in wild-type larvae, whereas ethanol did not. Thus ethanol and isopropanol exert some different toxic effects on larval fat bodies.
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Affiliation(s)
- B W Geer
- Department of Biology, Knox College, Galesburg, Illinois 61401
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