1
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Pan X, Dutta D, Lu S, Bellen HJ. Sphingolipids in neurodegenerative diseases. Front Neurosci 2023; 17:1137893. [PMID: 36875645 PMCID: PMC9978793 DOI: 10.3389/fnins.2023.1137893] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 01/27/2023] [Indexed: 02/18/2023] Open
Abstract
Neurodegenerative Diseases (NDDs) are a group of disorders that cause progressive deficits of neuronal function. Recent evidence argues that sphingolipid metabolism is affected in a surprisingly broad set of NDDs. These include some lysosomal storage diseases (LSDs), hereditary sensory and autonomous neuropathy (HSAN), hereditary spastic paraplegia (HSP), infantile neuroaxonal dystrophy (INAD), Friedreich's ataxia (FRDA), as well as some forms of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). Many of these diseases have been modeled in Drosophila melanogaster and are associated with elevated levels of ceramides. Similar changes have also been reported in vertebrate cells and mouse models. Here, we summarize studies using fly models and/or patient samples which demonstrate the nature of the defects in sphingolipid metabolism, the organelles that are implicated, the cell types that are initially affected, and potential therapeutics for these diseases.
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Affiliation(s)
- Xueyang Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Debdeep Dutta
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, United States
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2
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Nagare M, Ayachit M, Agnihotri A, Schwab W, Joshi R. Glycosyltransferases: the multifaceted enzymatic regulator in insects. INSECT MOLECULAR BIOLOGY 2021; 30:123-137. [PMID: 33263941 DOI: 10.1111/imb.12686] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/26/2019] [Accepted: 11/27/2020] [Indexed: 05/23/2023]
Abstract
Glycosyltransferases (GTs) catalyse the reaction of glyco-conjugation of various biomolecules by transferring the saccharide moieties from an activated nucleotide sugar to nucleophilic glycosyl acceptor. In insects, GTs show diverse temporal and site-specific expression patterns and thus play significant roles in forming the complex biomolecular structures that are necessary for insect survival, growth and development. Several insects exhibit GT-mediated detoxification as a key defence strategy against plant allelochemicals and xenobiotic compounds, as well as a mechanism for pesticide cross-resistance. Also, these enzymes act as crucial effectors and modulators in various developmental processes of insects such as eye development, UV shielding, cuticle formation, epithelial development and other specialized functions. Furthermore, many of the known insect GTs have been shown to play a fundamental role in other physiological processes like body pigmentation, cuticular tanning, chemosensation and stress response. This review provides a detailed overview of the multifaceted functionality of insect GTs and summarizes numerous case studies associated with it.
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Affiliation(s)
- M Nagare
- Institute of Bioinformatics and Biotechnology (IBB), Savitribai Phule Pune University, Pune, India
| | - M Ayachit
- Institute of Bioinformatics and Biotechnology (IBB), Savitribai Phule Pune University, Pune, India
| | - A Agnihotri
- Institute of Bioinformatics and Biotechnology (IBB), Savitribai Phule Pune University, Pune, India
- School of Veterinary and Life Sciences, Western Australian State Agricultural Biotechnology Centre (SABC), Murdoch University, Perth, Western Australia, Australia
| | - W Schwab
- Biotechnology of Natural Products, Center of Life and Food Science Weihenstephan, Technical University of Munich, Freising, Germany
| | - R Joshi
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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3
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Faik A, Held M. Review: Plant cell wall biochemical omics: The high-throughput biochemistry for polysaccharide biosynthesis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 286:49-56. [PMID: 31300141 DOI: 10.1016/j.plantsci.2019.04.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 04/17/2019] [Accepted: 04/29/2019] [Indexed: 06/10/2023]
Abstract
Progress in the functional biochemical analysis of plant glycosyltransferases (GTs) has been slow because plant GTs are generally membrane proteins, operate as part of larger, multimeric complexes, and utilize a vast complexity of substrate acceptors. Therefore, the field would benefit from development of adequate high throughput expression as well as product detection and characterization techniques. Here we review current approaches to tackle such obstacles and suggest a new path forward: nucleic acid programmable protein arrays (NAPPA) with liquid sample desorption ionization (LS-DESI-MS) mass spectrometry. NAPPA utilizes in vitro transcription and translation to produce epitope-tagged fusion proteins from cloned GT cDNAs. LS-DESI is a soft ionization technique that allows rapid and sensitive MS-based product characterization in situ. Coupling both approaches provides the opportunity to examine individual GT functions as well as protein-protein interactions. Furthermore, advances in automated oligosaccharide synthesis and lipid nanodisc technology should allow testing of plant GT activity in presence of numerous substrate acceptors and lipid environments in a high throughput fashion. Thus, NAPPA-DESI-MS has great potential to make headway in biochemical characterization of the large number of plant GTs.
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Affiliation(s)
- Ahmed Faik
- Environmental and Plant Biology Department, Athens 45701, USA; Molecular and Cellular Biology Program, Ohio University, Athens 45701, USA.
| | - Michael Held
- Chemistry and Biochemistry Department, Athens 45701, USA; Molecular and Cellular Biology Program, Ohio University, Athens 45701, USA
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4
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Negreiros E, Herszterg S, Kang KH, Câmara A, Dias WB, Carneiro K, Bier E, Todeschini AR, Araujo H. N-linked glycosylation restricts the function of Short gastrulation to bind and shuttle BMPs. Development 2018; 145:dev.167338. [PMID: 30355725 DOI: 10.1242/dev.167338] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/14/2018] [Indexed: 12/11/2022]
Abstract
Disorders of N-linked glycosylation are increasingly reported in the literature. However, the targets that are responsible for the associated developmental and physiological defects are largely unknown. Bone morphogenetic proteins (BMPs) act as highly dynamic complexes to regulate several functions during development. The range and strength of BMP activity depend on interactions with glycosylated protein complexes in the extracellular milieu. Here, we investigate the role of glycosylation for the function of the conserved extracellular BMP antagonist Short gastrulation (Sog). We identify conserved N-glycosylated sites and describe the effect of mutating these residues on BMP pathway activity in Drosophila Functional analysis reveals that loss of individual Sog glycosylation sites enhances BMP antagonism and/or increases the spatial range of Sog effects in the tissue. Mechanistically, we provide evidence that N-terminal and stem glycosylation controls extracellular Sog levels and distribution. The identification of similar residues in vertebrate Chordin proteins suggests that N-glycosylation may be an evolutionarily conserved process that adds complexity to the regulation of BMP activity.
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Affiliation(s)
- Erika Negreiros
- Institute for Biomedical Sciences, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Sophie Herszterg
- Institute for Biomedical Sciences, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Kyung-Hwa Kang
- Division of Biological Sciences, University of California at San Diego, CA 92093-0349, USA
| | - Amanda Câmara
- Institute for Biomedical Sciences, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Wagner B Dias
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Katia Carneiro
- Institute for Biomedical Sciences, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Ethan Bier
- Division of Biological Sciences, University of California at San Diego, CA 92093-0349, USA
| | - Adriane Regina Todeschini
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902
| | - Helena Araujo
- Institute for Biomedical Sciences, Federal University of Rio de Janeiro, RJ, Brazil, 21941-902 .,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Brasil (INCT-ENEM)
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5
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Huang Y, Huang S, Di Scala C, Wang Q, Wandall HH, Fantini J, Zhang YQ. The glycosphingolipid MacCer promotes synaptic bouton formation in Drosophila by interacting with Wnt. eLife 2018; 7:38183. [PMID: 30355446 PMCID: PMC6202054 DOI: 10.7554/elife.38183] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 09/09/2018] [Indexed: 01/05/2023] Open
Abstract
Lipids are structural components of cellular membranes and signaling molecules that are widely involved in development and diseases, but the underlying molecular mechanisms are poorly understood, partly because of the vast variety of lipid species and complexity of synthetic and turnover pathways. From a genetic screen, we identify that mannosyl glucosylceramide (MacCer), a species of glycosphingolipid (GSL), promotes synaptic bouton formation at the Drosophila neuromuscular junction (NMJ). Pharmacological and genetic analysis shows that the NMJ growth-promoting effect of MacCer depends on normal lipid rafts, which are known to be composed of sphingolipids, sterols and select proteins. MacCer positively regulates the synaptic level of Wnt1/Wingless (Wg) and facilitates presynaptic Wg signaling, whose activity is raft-dependent. Furthermore, a functional GSL-binding motif in Wg exhibiting a high affinity for MacCer is required for normal NMJ growth. These findings reveal a novel mechanism whereby the GSL MacCer promotes synaptic bouton formation via Wg signaling.
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Affiliation(s)
- Yan Huang
- Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, CAS Center for Excellence in Brain Science and Intelligence Technology, Beijing, China
| | - Sheng Huang
- Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, CAS Center for Excellence in Brain Science and Intelligence Technology, Beijing, China.,Sino-Danish College, Sino-Danish Center for Education and Research, Chinese Academy of Sciences, Beijing, China
| | | | - Qifu Wang
- Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, CAS Center for Excellence in Brain Science and Intelligence Technology, Beijing, China
| | - Hans H Wandall
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacques Fantini
- UNIS UMR_S 1072, INSERM, Aix-Marseille Université, Marseille, France
| | - Yong Q Zhang
- Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, CAS Center for Excellence in Brain Science and Intelligence Technology, Beijing, China
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6
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Itonori S, Hashimoto K, Nakagawa M, Harada M, Suzuki T, Kojima H, Ito M, Sugita M. Structural analysis of neutral glycosphingolipids from the silkworm Bombyx mori and the difference in ceramide composition between larvae and pupae. J Biochem 2018; 163:201-214. [PMID: 29069405 DOI: 10.1093/jb/mvx072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Accepted: 09/08/2017] [Indexed: 01/06/2023] Open
Abstract
Glycosphingolipids (GSLs) from the silkworm Bombyx mori were identified and GSL expression patterns between larvae and pupae were compared. The structural analysis of neutral GSLs from dried pupae revealed the following predominant species: Glcβ1Cer, Manβ4Glcβ1Cer, GlcNAcβ3Manβ4Glcβ1Cer, Galβ3Manβ4Glcβ1Cer, GalNAcα4Galβ3Manβ4Glcβ1Cer, GlcNAcβ3Galβ3Manβ4Glcβ1Cer, Galα4Galβ3Manβ4Glcβ1Cer and (GalNAcα4)1-4 GalNAcα4Galβ3Manβ4Glcβ1Cer. Lin-ear elongation of α4-GalNAc was observed at the non-reducing end of Galβ3Manβ4Glcβ1Cer with up to five GalNAc repeats. The arthro-series GSL GlcNAcβ3Manβ4Glcβ1Cer, a characteristic GSL-glycan sequence of other Arthropoda, was detected in silkworms. The main ceramide species in each purified GSL fraction were h20:0-d14:1 and h22:0-d14:1. GSL expression patterns in larvae and pupae were compared using thin-layer chromatography, which demonstrated differences among acidic, polar and neutral GSL fractions, while the zwitterionic fraction showed no difference. Neutral GSLs such as ceramides di-, tri- and tetrasaccharides in larvae showed less abundant than those in pupae. MALDI-TOF MS analysis revealed that larval GSLs contained four types of ceramide species, whereas pupal GSLs contained only two types. The structural analysis of neutral GSLs from silkworms revealed a novel series of GSLs. The comparison of GSL expression patterns between larvae and pupae demonstrated differences in several fractions. Alterations in GSL ceramide composition between larvae and pupae were observed by MALDI-TOF MS analysis.
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Affiliation(s)
- Saki Itonori
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Kyouhei Hashimoto
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Mika Nakagawa
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Masashi Harada
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Takae Suzuki
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Hisao Kojima
- Department of Bioinformatics, Institute of Science and Engineering, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Masahiro Ito
- Department of Bioinformatics, Institute of Science and Engineering, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Mutsumi Sugita
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1, Hiratsu, Otsu, Shiga 520-0862, Japan
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7
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Gerdøe-Kristensen S, Lund VK, Wandall HH, Kjaerulff O. Mactosylceramide prevents glial cell overgrowth by inhibiting insulin and fibroblast growth factor receptor signaling. J Cell Physiol 2017; 232:3112-3127. [PMID: 28019653 DOI: 10.1002/jcp.25762] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 12/22/2016] [Accepted: 12/22/2016] [Indexed: 12/13/2022]
Abstract
Receptor tyrosine kinase (RTK) signaling controls key aspects of cellular differentiation, proliferation, survival, metabolism, and migration. Deregulated RTK signaling also underlies many cancers. Glycosphingolipids (GSL) are essential elements of the plasma membrane. By affecting clustering and activity of membrane receptors, GSL modulate signal transduction, including that mediated by the RTK. GSL are abundant in the nervous system, and glial development in Drosophila is emerging as a useful model for studying how GSL modulate RTK signaling. Drosophila has a simple GSL biosynthetic pathway, in which the mannosyltransferase Egghead controls conversion of glucosylceramide (GlcCer) to mactosylceramide (MacCer). Lack of elongated GSL in egghead (egh) mutants causes overgrowth of subperineurial glia (SPG), largely due to aberrant activation of phosphatidylinositol 3-kinase (PI3K). However, to what extent this effect involves changes in upstream signaling events is unresolved. We show here that glial overgrowth in egh is strongly linked to increased activation of Insulin and fibroblast growth factor receptors (FGFR). Glial hypertrophy is phenocopied when overexpressing gain-of-function mutants of the Drosophila insulin receptor (InR) and the FGFR homolog Heartless (Htl) in wild type SPG, and is suppressed by inhibiting Htl and InR activity in egh. Knockdown of GlcCer synthase in the SPG fails to suppress glial overgrowth in egh nerves, and slightly promotes overgrowth in wild type, suggesting that RTK hyperactivation is caused by absence of MacCer and not by GlcCer accumulation. We conclude that an early product in GSL biosynthesis, MacCer, prevents inappropriate activation of insulin and fibroblast growth factor receptors in Drosophila glia.
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Affiliation(s)
- Stine Gerdøe-Kristensen
- Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.,Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Viktor K Lund
- Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Hans H Wandall
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Ole Kjaerulff
- Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
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8
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Huang Y, Huang S, Lam SM, Liu Z, Shui G, Zhang YQ. Acsl, the Drosophila ortholog of intellectual-disability-related ACSL4, inhibits synaptic growth by altered lipids. J Cell Sci 2016; 129:4034-4045. [PMID: 27656110 DOI: 10.1242/jcs.195032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 09/16/2016] [Indexed: 12/17/2022] Open
Abstract
Nervous system development and function are tightly regulated by metabolic processes, including the metabolism of lipids such as fatty acids. Mutations in long-chain acyl-CoA synthetase 4 (ACSL4) are associated with non-syndromic intellectual disabilities. We previously reported that Acsl, the Drosophila ortholog of mammalian ACSL3 and ACSL4, inhibits neuromuscular synapse growth by suppressing bone morphogenetic protein (BMP) signaling. Here, we report that Acsl regulates the composition of fatty acids and membrane lipids, which in turn affects neuromuscular junction (NMJ) synapse development. Acsl mutant brains had a decreased abundance of C16:1 fatty acyls; restoration of Acsl expression abrogated NMJ overgrowth and the increase in BMP signaling. A lipidomic analysis revealed that Acsl suppressed the levels of three lipid raft components in the brain, including mannosyl glucosylceramide (MacCer), phosphoethanolamine ceramide and ergosterol. The MacCer level was elevated in Acsl mutant NMJs and, along with sterol, promoted NMJ overgrowth, but was not associated with the increase in BMP signaling in the mutants. These findings suggest that Acsl inhibits NMJ growth by stimulating C16:1 fatty acyl production and concomitantly suppressing raft-associated lipid levels.
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Affiliation(s)
- Yan Huang
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sheng Huang
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,Sino-Danish College, Sino-Danish Center for Education and Research, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Sin Man Lam
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhihua Liu
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Guanghou Shui
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yong Q Zhang
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
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9
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Zhang D, Xiao Y, Hussain Dhiloo K, Soberon M, Bravo A, Wu K. Molecular Cloning, Expression, and Identification of Bre Genes Involved in Glycosphingolipids Synthesis in Helicoverpa armigera (Lepidoptera: Noctuidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2016; 109:1415-1423. [PMID: 27190043 DOI: 10.1093/jee/tow040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/09/2016] [Accepted: 02/12/2016] [Indexed: 06/05/2023]
Abstract
Glycosphingolipids (GSLs) play important roles in the cellular biology of vertebrate and invertebrate organisms, such as cell differentiation, tumor metastasis, and cell coordination. GSLs also serve as receptors for different bacterial toxins . For example, in the nematode Caenorhabditis elegans , GSLs function as receptors of the insecticidal Cry toxins produced by Bacillus thuringiensis (Bt), and mutations in bre genes involved in GSLs synthesis resulted in resistance to Cry5 toxin in this organism. However, the information of GSLs function in insects is still limited. In this study, three genes for glycosyltransferases, bre 2, bre 3, and bre 4, from Helicoverpa armigera were identified and cloned. The previously reported bre5 gene from H. armigera was also analyzed. Protein sequence alignments revealed that proteins codified by H. armigera Bre shared high identity with homologous proteins from other organisms. Expression profile analysis revealed that the expressions of bre genes varied in the different tissues and also in the different developmental stages of H. armigera. Finally, the heterologous expression of bre genes in Trichoplusia ni Hi5 cell line showed that the corresponding translated proteins were localized in the cytoplasm of Hi5 cells. These results provide the bases for further functional studies of bre genes and analyzing potential roles of GSLs in mode of action of Cry1A toxin in H. armigera.
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10
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Yamamoto-Hino M, Yoshida H, Ichimiya T, Sakamura S, Maeda M, Kimura Y, Sasaki N, Aoki-Kinoshita KF, Kinoshita-Toyoda A, Toyoda H, Ueda R, Nishihara S, Goto S. Phenotype-based clustering of glycosylation-related genes by RNAi-mediated gene silencing. Genes Cells 2015; 20:521-42. [PMID: 25940448 PMCID: PMC4682476 DOI: 10.1111/gtc.12246] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 03/24/2015] [Indexed: 01/16/2023]
Abstract
Glycan structures are synthesized by a series of reactions conducted by glycosylation-related (GR) proteins such as glycosyltransferases, glycan-modifying enzymes, and nucleotide-sugar transporters. For example, the common core region of glycosaminoglycans (GAGs) is sequentially synthesized by peptide-O-xylosyltransferase, β1,4-galactosyltransferase I, β1,3-galactosyltransferase II, and β1,3-glucuronyltransferase. This raises the possibility that functional impairment of GR proteins involved in synthesis of the same glycan might result in the same phenotypic abnormality. To examine this possibility, comprehensive silencing of genes encoding GR and proteoglycan core proteins was conducted in Drosophila. Drosophila GR candidate genes (125) were classified into five functional groups for synthesis of GAGs, N-linked, O-linked, Notch-related, and unknown glycans. Spatiotemporally regulated silencing caused a range of malformed phenotypes that fell into three types: extra veins, thick veins, and depigmentation. The clustered phenotypes reflected the biosynthetic pathways of GAGs, Fringe-dependent glycan on Notch, and glycans placed at or near nonreducing ends (herein termed terminal domains of glycans). Based on the phenotypic clustering, CG33145 was predicted to be involved in formation of terminal domains. Our further analysis showed that CG33145 exhibited galactosyltransferase activity in synthesis of terminal N-linked glycans. Phenotypic clustering, therefore, has potential for the functional prediction of novel GR genes.
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Affiliation(s)
- Miki Yamamoto-Hino
- Department of Life Science, Rikkyo University, Toshima-ku, Tokyo, Japan.,Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan
| | - Hideki Yoshida
- Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan.,Department of Bioinformatics, Faculty of Engineering, Soka University, Hachioji, Tokyo, Japan.,Department of Applied Biology, Insect Biomedical Research Center, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan
| | - Tomomi Ichimiya
- Department of Bioinformatics, Faculty of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Sho Sakamura
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Megumi Maeda
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Yoshinobu Kimura
- Department of Biofunctional Chemistry, Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Norihiko Sasaki
- Department of Bioinformatics, Faculty of Engineering, Soka University, Hachioji, Tokyo, Japan.,Research Team for Geriatric Medicine (Vascular Medicine), Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan
| | - Kiyoko F Aoki-Kinoshita
- Department of Bioinformatics, Faculty of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Akiko Kinoshita-Toyoda
- Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan.,College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Hidenao Toyoda
- Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan.,College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Ryu Ueda
- Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan.,Invertebrate Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Shoko Nishihara
- Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan.,Department of Bioinformatics, Faculty of Engineering, Soka University, Hachioji, Tokyo, Japan
| | - Satoshi Goto
- Department of Life Science, Rikkyo University, Toshima-ku, Tokyo, Japan.,Core Research for Evolutional Science and Technology (CREST) of Japan Science and Technology Agency (JST), Kawaguchi, Saitama, Japan
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11
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Mutations in the IMD pathway and mustard counter Vibrio cholerae suppression of intestinal stem cell division in Drosophila. mBio 2013; 4:e00337-13. [PMID: 23781070 PMCID: PMC3684835 DOI: 10.1128/mbio.00337-13] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vibrio cholerae is an estuarine bacterium and an intestinal pathogen of humans that causes severe epidemic diarrhea. In the absence of adequate mammalian models in which to study the interaction of V. cholerae with the host intestinal innate immune system, we have implemented Drosophila melanogaster as a surrogate host. We previously showed that immune deficiency pathway loss-of-function and mustard gain-of-function mutants are less susceptible to V. cholerae infection. We find that although the overall burden of intestinal bacteria is not significantly different from that of control flies, intestinal stem cell (ISC) division is increased in these mutants. This led us to examine the effect of V. cholerae on ISC division. We report that V. cholerae infection and cholera toxin decrease ISC division. Because IMD pathway and Mustard mutants, which are resistant to V. cholerae, maintain higher levels of ISC division during V. cholerae infection, we hypothesize that suppression of ISC division is a virulence strategy of V. cholerae and that accelerated epithelial regeneration protects the host against V. cholerae. Extension of these findings to mammals awaits the development of an adequate experimental model.
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12
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Katoh T, Tiemeyer M. The N's and O's of Drosophila glycoprotein glycobiology. Glycoconj J 2012; 30:57-66. [PMID: 22936173 DOI: 10.1007/s10719-012-9442-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 08/13/2012] [Indexed: 11/28/2022]
Abstract
The past 25 years have seen significant advances in understanding the diversity and functions of glycoprotein glycans in Drosophila melanogaster. Genetic screens have captured mutations that reveal important biological activities modulated by glycans, including protein folding and trafficking, as well as cell signaling, tissue morphogenesis, fertility, and viability. Many of these glycan functions have parallels in vertebrate development and disease, providing increasing opportunities to dissect pathologic mechanisms using Drosophila genetics. Advances in the sensitivity of structural analytic techniques have allowed the glycan profiles of wild-type and mutant tissues to be assessed, revealing novel glycan structures that may be functionally analogous to vertebrate glycans. This review describes a selected set of recent advances in understanding the functions of N-linked and O-linked (non-glycosaminoglycan) glycoprotein glycans in Drosophila with emphasis on their relatedness to vertebrate organisms.
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Affiliation(s)
- Toshihiko Katoh
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA
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13
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Neurofibromatosis-like phenotype in Drosophila caused by lack of glucosylceramide extension. Proc Natl Acad Sci U S A 2012; 109:6987-92. [PMID: 22493273 DOI: 10.1073/pnas.1115453109] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Glycosphingolipids (GSLs) are of fundamental importance in the nervous system. However, the molecular details associated with GSL function are largely unknown, in part because of the complexity of GSL biosynthesis in vertebrates. In Drosophila, only one major GSL biosynthetic pathway exists, controlled by the glycosyltransferase Egghead (Egh). Here we discovered that loss of Egh causes overgrowth of peripheral nerves and attraction of immune cells to the nerves. This phenotype is reminiscent of the human disorder neurofibromatosis type 1, which is characterized by disfiguring nerve sheath tumors with mast cell infiltration, increased cancer risk, and learning deficits. Neurofibromatosis type 1 is due to a reduction of the tumor suppressor neurofibromin, a negative regulator of the small GTPase Ras. Enhanced Ras signaling promotes glial growth through activation of phosphatidylinositol 3-kinase (PI3K) and its downstream kinase Akt. We find that overgrowth of peripheral nerves in egh mutants is suppressed by down-regulation of the PI3K signaling pathway by expression of either dominant-negative PI3K, the tumor suppressor PTEN, or the transcription factor FOXO in the subperineurial glia. These results show that loss of the glycosyltransferase Egh affects membrane signaling and activation of PI3K signaling in glia of the peripheral nervous system, and suggest that glycosyltransferases may suppress proliferation.
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14
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Pontier SM, Schweisguth F. Glycosphingolipids in signaling and development: From liposomes to model organisms. Dev Dyn 2011; 241:92-106. [DOI: 10.1002/dvdy.22766] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2011] [Indexed: 01/05/2023] Open
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15
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Kojima H, Shimizu T, Sugita M, Itonori S, Fujita N, Ito M. Biochemical studies on sphingolipids of Artemia franciscana: novel neutral glycosphingolipids. J Lipid Res 2011; 52:308-17. [PMID: 21062954 PMCID: PMC3023551 DOI: 10.1194/jlr.m010173] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 10/15/2010] [Indexed: 12/27/2022] Open
Abstract
Neutral glycosphingolipids containing one to six sugars in their oligosaccharide chains have been isolated from cysts of the brine shrimp Artemia franciscana. The structures of these glycolipids were identified by methylation analysis, partial acid hydrolysis, gas-liquid chromatography, combined gas-liquid chromatography-mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and proton nuclear magnetic resonance spectroscopy to be Glcβ1-Cer, Manβ1-4Glcβ1-Cer, Fucα1-3Manβ1-4Glcβ1-Cer, GlcNAcβ1-3Manβ1-4Glcβ1-Cer, GlcNAcα1-2Fucα1-3Manβ1-4Glcβ1-Cer, GalNAcβ1-4GlcNAcβ1-3Manβ1-4Glcβ1-Cer, GalNAcβ1-4(Fucα1-3)GlcNAcβ1-3Manβ1-4Glcβ1-Cer (CPS), and GalNAcβ1-4(GlcNAcα1-2Fucα1-3)GlcNAcβ1-3Manβ1-4Glcβ1-Cer (CHS). Two glycosphingolipids, CPS and CHS, were characterized as novel structures. Because Artemia contains a certain series of glycosphingolipids (-Fucα3Manβ4GlcβCer), which differ from the core sugar sequences reported thus far, we tentatively designated the glycosphingolipids characterized as nonarthro-series ones. Furthermore, CHS exhibited a hybrid structure of arthro-series and nonarthro-series sugar chain. Two novel glycosphingolipids were characterized from the brine shrimp Artemia franciscana; one was composed of arthrotetraose and a branching fucose attached to N-acetylglucosamine residue, and the other was composed of CPS with an additional N-acetylglucosamine residue attached to the branching fucose.
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Affiliation(s)
- Hisao Kojima
- Department of Bioinformatics, Faculty of Pharmacy, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1 Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Takemasa Shimizu
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1 Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Mutsumi Sugita
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1 Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Saki Itonori
- Department of Chemistry, Faculty of Liberal Arts and Education, Shiga University, 2-5-1 Hiratsu, Otsu, Shiga 520-0862, Japan
| | - Norihisa Fujita
- Institute of Science and Engineering, and Laboratory of Pharmcoinformatics, Faculty of Pharmacy, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Masahiro Ito
- Department of Bioinformatics, Faculty of Pharmacy, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
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Abstract
The last 10 years have seen a rebirth of interest in lipid biology in the fields of Drosophila development and neurobiology, and sphingolipids have emerged as controlling many processes that have not previously been studied from the viewpoint of lipid biochemistry. Mutations in sphingolipid regulatory enzymes have been pinpointed as affecting cell survival and growth in tissues ranging from muscle to retina. Specification of cell types are also influenced by sphingolipid regulatory pathways, as genetic interactions of glycosphingolipid biosynthetic enzymes with many well-known signaling receptors such as Notch and epidermal growth factor receptor reveal. Furthermore, studies in flies are now uncovering unexpected roles of sphingolipids in controlling lipid storage and response to nutrient availability. The sophisticated genetics of Drosophila is particularly well suited to uncover the roles of sphingolipid regulatory enzymes in development and metabolism, especially in light of conserved pathways that are present in both flies and mammals. The challenges that remain in the field of sphingolipid biology in Drosophila are to combine traditional developmental genetics with more analytical biochemical and biophysical methods, to quantify and localize the responses of these lipids to genetic and metabolic perturbations.
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Affiliation(s)
- Rachel Kraut
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
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17
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Ellis LL, Carney GE. Socially-responsive gene expression in male Drosophila melanogaster is influenced by the sex of the interacting partner. Genetics 2011; 187:157-69. [PMID: 20980240 PMCID: PMC3018301 DOI: 10.1534/genetics.110.122754] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 10/20/2010] [Indexed: 11/18/2022] Open
Abstract
Behavior is influenced by an organism's genes and environment, including its interactions with same or opposite sex individuals. Drosophila melanogaster perform innate, yet socially modifiable, courtship behaviors that are sex specific and require rapid integration and response to multiple sensory cues. Furthermore, males must recognize and distinguish other males from female courtship objects. It is likely that perception, integration, and response to sex-specific cues is partially mediated by changes in gene expression. Reasoning that social interactions with members of either sex would impact gene expression, we compared expression profiles in heads of males that courted females, males that interacted with other males, or males that did not interact with another fly. Expression of 281 loci changes when males interact with females, whereas 505 changes occur in response to male-male interactions. Of these genes, 265 are responsive to encounters with either sex and 240 respond specifically to male-male interactions. Interestingly, 16 genes change expression only when a male courts a female, suggesting that these changes are a specific response to male-female courtship interactions. We supported our hypothesis that socially-responsive genes can function in behavior by showing that egghead (egh) expression, which increases during social interactions, is required for robust male-to-female courtship. We predict that analyzing additional socially-responsive genes will give us insight into genes and neural signaling pathways that influence reproductive and other behavioral interactions.
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Affiliation(s)
| | - Ginger E. Carney
- Department of Biology, Texas A&M University, College Station, Texas 77843-3258
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18
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Hamel S, Fantini J, Schweisguth F. Notch ligand activity is modulated by glycosphingolipid membrane composition in Drosophila melanogaster. ACTA ACUST UNITED AC 2010; 188:581-94. [PMID: 20176925 PMCID: PMC2828914 DOI: 10.1083/jcb.200907116] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Endocytosis of the transmembrane ligands Delta (Dl) and Serrate (Ser) is required for the proper activation of Notch receptors. The E3 ubiquitin ligases Mindbomb1 (Mib1) and Neuralized (Neur) regulate the ubiquitination of Dl and Ser and thereby promote both ligand endocytosis and Notch receptor activation. In this study, we identify the alpha1,4-N-acetylgalactosaminyltransferase-1 (alpha4GT1) gene as a gain of function suppressor of Mib1 inhibition. Expression of alpha4GT1 suppressed the signaling and endocytosis defects of Dl and Ser resulting from the inhibition of mib1 and/or neur activity. Genetic and biochemical evidence indicate that alpha4GT1 plays a regulatory but nonessential function in Notch signaling via the synthesis of a specific glycosphingolipid (GSL), N5, produced by alpha4GT1. Furthermore, we show that the extracellular domain of Ser interacts with GSLs in vitro via a conserved GSL-binding motif, raising the possibility that direct GSL-protein interactions modulate the endocytosis of Notch ligands. Together, our data indicate that specific GSLs modulate the signaling activity of Notch ligands.
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Affiliation(s)
- Sophie Hamel
- Institut Pasteur, Centre National de la Recherche Scientifique URA2578, 75724 Paris, Cedex 15, France
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19
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Abstract
Notch and the DSL Notch ligands Delta and Serrate/Jagged are glycoproteins with a single transmembrane domain. The extracellular domain (ECD) of both Notch receptors and Notch ligands contains numerous epidermal growth factor (EGF)-like repeats which are post-translationally modified by a variety of glycans. Inactivation of a subset of genes that encode glycosyltransferases which initiate and elongate these glycans inhibits Notch signaling. In the formation of developmental boundaries in Drosophila and mammals, in mouse T-cell and marginal zone B-cell development, and in co-culture Notch signaling assays, the regulation of Notch signaling by glycans is to date a cell-autonomous effect of the Notch-expressing cell. The regulation of Notch signaling by glycans represents a new paradigm of signal transduction. O-fucose glycans modulate the strength of Notch binding to DSL Notch ligands, while O-glucose glycans facilitate juxta-membrane cleavage of Notch, generating the substrate for intramembrane cleavage and Notch activation. Identifying precisely how the addition of particular sugars at specific locations on Notch modifies Notch signaling is a challenge for the future.
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Affiliation(s)
- Pamela Stanley
- Department of Cell Biology, Albert Einstein College Medicine, New York, USA
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20
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Johswich A, Kraft B, Wuhrer M, Berger M, Deelder AM, Hokke CH, Gerardy-Schahn R, Bakker H. Golgi targeting of Drosophila melanogaster beta4GalNAcTB requires a DHHC protein family-related protein as a pilot. ACTA ACUST UNITED AC 2009; 184:173-83. [PMID: 19139268 PMCID: PMC2615082 DOI: 10.1083/jcb.200801071] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Drosophila melanogaster β4GalNAcTB mutant flies revealed that this particular N-acetylgalactosaminyltransferase is predominant in the formation of lacdiNAc (GalNAcβ1,4GlcNAc)-modified glycolipids, but enzymatic activity could not be confirmed for the cloned enzyme. Using a heterologous expression cloning approach, we isolated β4GalNAcTB together with β4GalNAcTB pilot (GABPI), a multimembrane-spanning protein related to Asp-His-His-Cys (DHHC) proteins but lacking the DHHC consensus sequence. In the absence of GABPI, inactive β4GalNAcTB is trapped in the endoplasmic reticulum (ER). Coexpression of β4GalNAcTB and GABPI generates the active enzyme that is localized together with GABPI in the Golgi. GABPI associates with β4GalNAcTB and, when expressed with an ER retention signal, holds active β4GalNAcTB in the ER. Importantly, treatment of isolated membrane vesicles with Triton X-100 disturbs β4GalNAcTB activity. This phenomenon occurs with multimembrane-spanning glycosyltransferases but is normally not a property of glycosyltransferases with one membrane anchor. In summary, our data provide evidence that GABPI is required for ER export and activity of β4GalNAcTB.
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Affiliation(s)
- Anita Johswich
- Department of Cellular Chemistry, Hannover Medical School, Hannover, Germany
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21
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Pizette S, Rabouille C, Cohen SM, Thérond P. Glycosphingolipids control the extracellular gradient of the Drosophila EGFR ligand Gurken. Development 2009; 136:551-61. [PMID: 19144719 DOI: 10.1242/dev.031104] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Glycosphingolipids (GSLs) are present in all eukaryotic membranes and are implicated in neuropathologies and tumor progression in humans. Nevertheless, their in vivo functions remain poorly understood in vertebrates, partly owing to redundancy in the enzymes elongating their sugar chains. In Drosophila, a single GSL biosynthetic pathway is present that relies on the activity of the Egghead and Brainiac glycosyltransferases. Mutations in these two enzymes abolish GSL elongation and yield oogenesis defects, providing a unique model system in which to study GSL roles in signaling in vivo. Here, we use egghead and brainiac mutants to show that GSLs are necessary for full activation of the EGFR pathway during oogenesis in a time-dependent manner. In contrast to results from in vitro studies, we find that GSLs are required in cells producing the TGFalpha-like ligand Gurken, but not in EGFR-expressing cells. Strikingly, we find that GSLs are not essential for Gurken trafficking and secretion. However, we characterize for the first time the extracellular Gurken gradient and show that GSLs affect its formation by controlling Gurken planar transport in the extracellular space. This work presents the first in vivo evidence that GSLs act in trans to regulate the EGFR pathway and shows that extracellular EGFR ligand distribution is tightly controlled by GSLs. Our study assigns a novel role for GSLs in morphogen diffusion, possibly through regulation of their conformation.
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Affiliation(s)
- Sandrine Pizette
- Institute of Developmental Biology and Cancer, Centre de Biochimie, Université de Nice, Parc Valrose, 06108 Nice Cedex 02, France.
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22
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ten Hagen KG, Zhang L, Tian E, Zhang Y. Glycobiology on the fly: developmental and mechanistic insights from Drosophila. Glycobiology 2008; 19:102-11. [PMID: 18824561 DOI: 10.1093/glycob/cwn096] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Drosophila melanogaster offers many unique advantages for deciphering the complexities of glycan biosynthesis and function. The completion of the Drosophila genome sequencing project as well as the comprehensive catalogue of existing mutations and phenotypes have lead to a prolific database where many of the genes involved in glycan synthesis, assembly, modification, and recognition have been identified and characterized. Recent biochemical and molecular studies have elucidated the structure of the glycans present in Drosophila. Powerful genetic approaches have uncovered a number of critical biological roles for glycans during development that impact on our understanding of their function during mammalian development. Here, we summarize key recent findings and provide evidence for the usefulness of this model organism in unraveling the complexities of glycobiology across many species.
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Affiliation(s)
- Kelly G ten Hagen
- Developmental Glycobiology Unit, NIDCR, National Institutes of Health, Building 30, 30 Convent Drive, MSC 4370, Bethesda, MD 20892-4370, USA.
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23
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Drosophila follicle cells: morphogenesis in an eggshell. Semin Cell Dev Biol 2008; 19:271-82. [PMID: 18304845 DOI: 10.1016/j.semcdb.2008.01.004] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Accepted: 01/16/2008] [Indexed: 01/15/2023]
Abstract
Epithelial morphogenesis is important for organogenesis and pivotal for carcinogenesis, but mechanisms that control it are poorly understood. The Drosophila follicular epithelium is a genetically tractable model to understand these mechanisms in vivo. This epithelium of follicle cells encases germline cells to create an egg. In this review, we summarize progress toward understanding mechanisms that maintain the epithelium or permit migrations essential for oogenesis. Cell-cell communication is important, but the same signals are used repeatedly to control distinct events. Understanding intrinsic mechanisms that alter responses to developmental signals will be important to understand regulation of cell shape and organization.
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24
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Fyrst H, Zhang X, Herr DR, Byun HS, Bittman R, Phan VH, Harris GL, Saba JD. Identification and characterization by electrospray mass spectrometry of endogenous Drosophila sphingadienes. J Lipid Res 2007; 49:597-606. [PMID: 18156591 DOI: 10.1194/jlr.m700414-jlr200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Sphingolipids comprise a complex group of lipids concentrated in membrane rafts and whose metabolites function as signaling molecules. Sphingolipids are conserved in Drosophila, in which their tight regulation is required for proper development and tissue integrity. In this study, we identified a new family of Drosophila sphingolipids containing two double bonds in the long chain base (LCB). The lipids were found at low levels in wild-type flies and accumulated markedly in Drosophila Sply mutants, which do not express sphingosine-1-phosphate lyase and are defective in sphingolipid catabolism. To determine the identity of the unknown lipids, purified whole fly lipid extracts were separated on a C18-HPLC column and analyzed using electrospray mass spectrometry. The lipids contain a LCB of either 14 or 16 carbons with conjugated double bonds at C4,6. The Delta(4,6)-sphingadienes were found as free LCBs, as phosphorylated LCBs, and as the sphingoid base in ceramides. The temporal and spatial accumulation of Delta(4,6)-sphingadienes in Sply mutants suggests that these lipids may contribute to the muscle degeneration observed in these flies.
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Affiliation(s)
- Henrik Fyrst
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA
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25
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Stolz A, Haines N, Pich A, Irvine KD, Hokke CH, Deelder AM, Gerardy-Schahn R, Wuhrer M, Bakker H. Distinct contributions of β4GalNAcTA and β4GalNAcTB to Drosophila glycosphingolipid biosynthesis. Glycoconj J 2007; 25:167-75. [PMID: 17876704 DOI: 10.1007/s10719-007-9069-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 07/19/2007] [Accepted: 08/01/2007] [Indexed: 12/20/2022]
Abstract
Drosophila melanogaster has two beta4-N-acetylgalactosaminyltransferases, beta4GalNAcTA and beta4GalNAcTB, that are able to catalyse the formation of lacdiNAc (GalNAcbeta,4GlcNAc). LacdiNAc is found as a structural element of Drosophila glycosphingolipids (GSLs) suggesting that beta4GalNAcTs contribute to the generation of GSL structures in vivo. Mutations in Egghead and Brainaic, enzymes that generate the beta4GalNAcT trisaccharide acceptor structure GlcNAcbeta,3Manbeta,4GlcbetaCer, are lethal. In contrast, flies doubly mutant for the beta4GalNAcTs are viable and fertile. Here, we describe the structural analysis of the GSLs in beta4GalNAcT mutants and find that in double mutant flies no lacdiNAc structure is generated and the trisaccharide GlcNAcbeta,3Manbeta,4GlcbetaCer accumulates. We also find that phosphoethanolamine transfer to GlcNAc in the trisaccharide does not occur, demonstrating that this step is dependent on prior or simultaneous transfer of GalNAc. By comparing GSL structures generated in the beta4GalNAcT single mutants we show that beta4GalNAcTB is the major enzyme for the overall GSL biosynthesis in adult flies. In beta4GalNAcTA mutants, composition of GSL structures is indistinguishable from wild-type animals. However, in beta4GalNAcTB mutants precursor structures are accumulating in different steps of GSL biosynthesis, without the complete loss of lacdiNAc, indicating that beta4GalNAcTA plays a minor role in generating GSL structures. Together our results demonstrate that both beta4GalNAcTs are able to generate lacdiNAc structures in Drosophila GSL, although with different contributions in vivo, and that the trisaccharide GlcNAcbeta,3Manbeta,4GlcbetaCer is sufficient to avoid the major phenotypic consequences associated with the GSL biosynthetic defects in Brainiac or Egghead.
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Affiliation(s)
- Anita Stolz
- Zelluläre Chemie, Zentrum Biochemie, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
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26
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Pigott CR, Ellar DJ. Role of receptors in Bacillus thuringiensis crystal toxin activity. Microbiol Mol Biol Rev 2007; 71:255-81. [PMID: 17554045 PMCID: PMC1899880 DOI: 10.1128/mmbr.00034-06] [Citation(s) in RCA: 402] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Bacillus thuringiensis produces crystalline protein inclusions with insecticidal or nematocidal properties. These crystal (Cry) proteins determine a particular strain's toxicity profile. Transgenic crops expressing one or more recombinant Cry toxins have become agriculturally important. Individual Cry toxins are usually toxic to only a few species within an order, and receptors on midgut epithelial cells have been shown to be critical determinants of Cry specificity. The best characterized of these receptors have been identified for lepidopterans, and two major receptor classes have emerged: the aminopeptidase N (APN) receptors and the cadherin-like receptors. Currently, 38 different APNs have been reported for 12 different lepidopterans. Each APN belongs to one of five groups that have unique structural features and Cry-binding properties. While 17 different APNs have been reported to bind to Cry toxins, only 2 have been shown to mediate toxin susceptibly in vivo. In contrast, several cadherin-like proteins bind to Cry toxins and confer toxin susceptibility in vitro, and disruption of the cadherin gene has been associated with toxin resistance. Nonetheless, only a small subset of the lepidopteran-specific Cry toxins has been shown to interact with cadherin-like proteins. This review analyzes the interactions between Cry toxins and their receptors, focusing on the identification and validation of receptors, the molecular basis for receptor recognition, the role of the receptor in resistant insects, and proposed models to explain the sequence of events at the cell surface by which receptor binding leads to cell death.
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Affiliation(s)
- Craig R Pigott
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
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27
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Chen YW, Pedersen JW, Wandall HH, Levery SB, Pizette S, Clausen H, Cohen SM. Glycosphingolipids with extended sugar chain have specialized functions in development and behavior of Drosophila. Dev Biol 2007; 306:736-49. [PMID: 17498683 DOI: 10.1016/j.ydbio.2007.04.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 03/27/2007] [Accepted: 04/11/2007] [Indexed: 12/18/2022]
Abstract
Glycosphingolipids (GSL) are glycosylated polar lipids in cell membranes essential for development of vertebrates as well as Drosophila. Mutants that impair enzymes involved in biosynthesis of GSL sugar chains provide a means to assess the functions of the sugar chains in vivo. The Drosophila glycosyltransferases Egghead and Brainiac are responsible for the 2nd and 3rd steps of GSL sugar chain elongation. Mutants lacking these enzymes are lethal and the nature of the defects that occur has suggested that GSL might impact on signaling by the Notch and EGFR pathways. Here we report on characterization of enzymes involved in the 4th and 5th steps of GSL sugar chain elongation in vitro and explore the biological consequences of removing the enzymes involved in step 4 in vivo. Two beta4-N-Acetylgalactosyltransferase enzymes can carry out step 4 (beta4GalNAcTA and beta4GalNAcTB), and while they may have overlapping activity, the mutants produce distinct phenotypes. The beta4GalNAcTA mutant displays behavioral defects, which are also observed in viable brainiac mutants, suggesting that proper locomotion and coordination primarily depend on GSL elongation. beta4GalNAcTB mutant animal shows ventralization of ovarian follicle cells, which is caused by defective EGFR signaling between the oocyte and the dorsal follicle cells to specify dorsal fate. GSL sequentially elongated by Egh, Brn and beta4GalNAcTB in the oocyte contribute to this signaling pathway. Despite the similar enzymatic activity, we provide evidence that the two enzymes are not functionally redundant in vivo, but direct distinct developmental functions of GSL.
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Affiliation(s)
- Ya-Wen Chen
- Developmental Biology Program, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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28
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Haines N, Stewart BA. Functional roles for beta1,4-N-acetlygalactosaminyltransferase-A in Drosophila larval neurons and muscles. Genetics 2007; 175:671-9. [PMID: 17151241 PMCID: PMC1800592 DOI: 10.1534/genetics.106.065565] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Accepted: 11/07/2006] [Indexed: 11/18/2022] Open
Abstract
Adult Drosophila mutant for the glycosyltransferase beta1,4-N-acetlygalactosaminyltransferase-A (beta4GalNAcTA) display an abnormal locomotion phenotype, indicating a role for this enzyme, and the glycan structures that it generates, in the neuromuscular system. To investigate the functional role of this enzyme in more detail, we turned to the accessible larval neuromuscular system and report here that larvae mutant for beta4GalNAcTA display distinct nerve and muscle phenotypes. Mutant larvae exhibit abnormal backward crawling, reductions in nerve terminal bouton number, decreased spontaneous transmitter-release frequency, and short, wide muscles. This muscle shape change appears to result from hypercontraction since the individual sarcomeres are shorter in mutant muscles. Analysis of muscle calcium signals showed altered calcium handling in the mutant, suggesting a mechanism by which hypercontraction could occur. All of these phenotypes can be rescued by a transgene carrying the beta4GalNAcTA genomic region. Tissue-specific expression, using the Gal4-UAS system, reveals that neural expression rescues the mutant crawling phenotype, while muscle expression rescues the muscle defect. Tissue-specific expression did not appear to rescue the decrease in neuromuscular junction bouton number, suggesting that this defect arises from cooperation between nerve and muscle. Altogether, these results suggest that beta4GalNAcTA has at least three distinct functional roles.
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Affiliation(s)
- Nicola Haines
- Department of Biology, University of Toronto, Mississauga, Ontario L5L 1C6, Canada.
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Soller M, Haussmann IU, Hollmann M, Choffat Y, White K, Kubli E, Schäfer MA. Sex-peptide-regulated female sexual behavior requires a subset of ascending ventral nerve cord neurons. Curr Biol 2006; 16:1771-82. [PMID: 16979554 DOI: 10.1016/j.cub.2006.07.055] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/18/2006] [Accepted: 07/25/2006] [Indexed: 11/24/2022]
Abstract
BACKGROUND Male-derived Sex-peptide (SP) elicits egg laying and rejection of courting males in mated Drosophila females. Little is known about the genes that specify the underlying neuronal circuits and mediate this switch in female sexual behavior. RESULTS Here we show that the egghead gene involved in glycosphingolipid biosynthesis provides an essential component to the SP response. We have isolated viable alleles of the vital egghead gene that abolish egghead expression from a distal promoter resulting in the absence of the largest transcript of this complex transcription unit. Temporally and spatially restricted expression of egghead revealed a requirement for egghead early in the development of apterous-expressing ventral nerve cord neurons to rescue the SP response. In viable egghead alleles, these ascending interneurons, three per abdominal and seven per thoracic hemisegment, fail to innervate the central brain. egghead expression in apterous neurons rescues neuronal targeting and the response to SP. Furthermore, neurotransmission in apterous neurons is required to elicit the SP response. CONCLUSION Together with the former finding of SP binding to afferent nerves , these results suggest that SP-mediated modification of sensory input switches female sexual behavior from the virgin to the mated state.
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Affiliation(s)
- Matthias Soller
- Department of Biology and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454, USA.
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Egelund J, Petersen BL, Motawia MS, Damager I, Faik A, Olsen CE, Ishii T, Clausen H, Ulvskov P, Geshi N. Arabidopsis thaliana RGXT1 and RGXT2 encode Golgi-localized (1,3)-alpha-D-xylosyltransferases involved in the synthesis of pectic rhamnogalacturonan-II. THE PLANT CELL 2006; 18:2593-607. [PMID: 17056709 PMCID: PMC1626629 DOI: 10.1105/tpc.105.036566] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Revised: 08/23/2006] [Accepted: 09/18/2006] [Indexed: 05/12/2023]
Abstract
Two homologous plant-specific Arabidopsis thaliana genes, RGXT1 and RGXT2, belong to a new family of glycosyltransferases (CAZy GT-family-77) and encode cell wall (1,3)-alpha-d-xylosyltransferases. The deduced amino acid sequences contain single transmembrane domains near the N terminus, indicative of a type II membrane protein structure. Soluble secreted forms of the corresponding proteins expressed in insect cells showed xylosyltransferase activity, transferring d-xylose from UDP-alpha-d-xylose to l-fucose. The disaccharide product was hydrolyzed by alpha-xylosidase, whereas no reaction was catalyzed by beta-xylosidase. Furthermore, the regio- and stereochemistry of the methyl xylosyl-fucoside was determined by nuclear magnetic resonance to be an alpha-(1,3) linkage, demonstrating the isolated glycosyltransferases to be (1,3)-alpha-d-xylosyltransferases. This particular linkage is only known in rhamnogalacturonan-II, a complex polysaccharide essential to vascular plants, and is conserved across higher plant families. Rhamnogalacturonan-II isolated from both RGXT1 and RGXT2 T-DNA insertional mutants functioned as specific acceptor molecules in the xylosyltransferase assay. Expression of RGXT1- and RGXT2-enhanced green fluorescent protein constructs in Arabidopsis revealed that both fusion proteins were targeted to a Brefeldin A-sensitive compartment and also colocalized with the Golgi marker dye BODIPY TR ceramide, consistent with targeting to the Golgi apparatus. Taken together, these results suggest that RGXT1 and RGXT2 encode Golgi-localized (1,3)-alpha-d-xylosyltransferases involved in the biosynthesis of pectic rhamnogalacturonan-II.
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Affiliation(s)
- Jack Egelund
- Biotechnology Group, Danish Institute of Agricultural Sciences and Center for Molecular Plant Physiology, DK-1871 Frederiksberg C, Denmark
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31
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Shi H, Tan J, Schachter H. N-glycans are involved in the response of Caenorhabditis elegans to bacterial pathogens. Methods Enzymol 2006; 417:359-89. [PMID: 17132514 DOI: 10.1016/s0076-6879(06)17022-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Caenorhabditis elegans is becoming a popular tool for the study of glycan function particularly as it applies to development. More than 150 C. elegans genes have been identified as homologs of vertebrate genes involved in glycan metabolism. However, only a relatively small number of these genes have been expressed and studied in any detail. Oligomannose N-glycans (Man5-9GlcNAc2Asn), major components of the N-glycans of all eukaryotes including C. elegans, are essential, at least in part, for eukaryote survival, because they play an important role in protein quality control. In addition, vertebrates make hybrid (GlcNAcMan3-5GlcNAc2Asn) and complex (XGlcNAc2-6Man3GlcNAc2Asn) but little or no paucimannose (Man3-4GlcNAc2Asn)N-glycans, whereas plants, insects, and C. elegans make paucimannose but little or no hybrid nor complex N-glycans. UDP-GlcNAc:alpha3-D-mannoside beta1,2-N-acetylglucosaminyltransferase I (encoded by the gene Mgat1) controls the synthesis of hybrid, complex, and paucimannose N-glycans in all eukaryotes. C. elegans has three genes encoding beta1,2-N-acetylglucosaminyltransferase I (gly-12, gly-13, gly-14). To determine the functional requirement for this enzyme in worms, we generated seven worm strains with mutations in these three genes (gly-12, dpy-6 gly-13, gly-14, gly-12 gly-13, gly-14;gly-12, gly-14;dpy-6 gly-13 and gly-14;gly-12 gly-13). Whereas mice and Drosophila melanogaster with null mutations in Mgat1 suffer severe developmental abnormalities, all seven C. elegans strains with null mutations in the genes encoding beta1,2-N-acetylglucosaminyltransferase I develop normally and seem to have a wild-type phenotype. We now present evidence that beta1,2-N-acetylglucosaminyltransferase I-dependent N-glycans (consisting mainly of paucimannose N-glycans) play a role in the interaction of C. elegans with pathogenic bacteria, suggesting that these N-glycans are components of the worm's innate immune system.
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Affiliation(s)
- Hui Shi
- Program in Structural Biology and Biochemistry, Hospital for Sick Children, Toronto, Ontario, Canada
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32
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Fan Y, Soller M, Flister S, Hollmann M, Müller M, Bello B, Egger B, White K, Schäfer MA, Reichert H. The egghead gene is required for compartmentalization in Drosophila optic lobe development. Dev Biol 2005; 287:61-73. [PMID: 16182276 DOI: 10.1016/j.ydbio.2005.08.031] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Revised: 08/15/2005] [Accepted: 08/16/2005] [Indexed: 11/18/2022]
Abstract
The correct targeting of photoreceptor neurons (R-cells) in the developing Drosophila visual system requires multiple guidance systems in the eye-brain complex as well as the precise organization of the target area. Here, we report that the egghead (egh) gene, encoding a glycosyltransferase, is required for a compartment boundary between lamina glia and lobula cortex, which is necessary for appropriate R1-R6 innervation of the lamina. In the absence of egh, R1-R6 axons form a disorganized lamina plexus and some R1-R6 axons project abnormally to the medulla instead of the lamina. Mosaic analysis demonstrates that this is not due to a loss of egh function in the eye or in the neurons and glia of the lamina. Rather, as indicated by clonal analysis and cell-specific genetic rescue experiments, egh is required in cells of the lobula complex primordium which transiently abuts the lamina and medulla in the developing larval brain. In the absence of egh, perturbation of sheath-like glial processes occurs at the boundary region delimiting lamina glia and lobula cortex, and inappropriate invasion of lobula cortex cells across this boundary region disrupts the pattern of lamina glia resulting in inappropriate R1-R6 innervation. This finding underscores the importance of the lamina/lobula compartment boundary in R1-R6 axon targeting.
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Affiliation(s)
- Yun Fan
- Biozentrum/Pharmazentrum, University of Basel, Klingelbergstrasse 50, CH-4056 Basel, Switzerland.
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33
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Katic I, Vallier LG, Greenwald I. New positive regulators of lin-12 activity in Caenorhabditis elegans include the BRE-5/Brainiac glycosphingolipid biosynthesis enzyme. Genetics 2005; 171:1605-15. [PMID: 16157663 PMCID: PMC1389698 DOI: 10.1534/genetics.105.048041] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Screens for suppressors of lin-12 hypermorphic alleles in C. elegans have identified core components and modulators of the LIN-12/Notch signaling pathway. Here we describe the recovery of alleles of six new genes from a screen for suppressors of the egg-laying defect associated with elevated lin-12 activity. The molecular identification of one of the new suppressor genes revealed it as bre-5, which had previously been identified in screens for mutations that confer resistance to Bt toxin in C. elegans. bre-5 is the homolog of D. melanogaster brainiac. BRE-5/Brainiac catalyzes a step in the synthesis of glycosphingolipids, components of lipid rafts that are thought to act as platforms for association among certain kinds of membrane-bound proteins. Reducing the activity of several other genes involved in glycosphingolipid biosynthesis also suppresses the effects of constitutive lin-12 activity. Genetic analysis and cell ablation experiments suggest that bre-5 functions prior to ligand-induced ectodomain shedding that activates LIN-12 for signal transduction.
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Affiliation(s)
- Iskra Katic
- Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University College of Physicians and Surgeons, 701 W. 168th Street, New York, NY 10032, USA
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Fuller MD, Schwientek T, Wandall HH, Pedersen JW, Clausen H, Levery SB. Structure elucidation of neutral, di-, tri-, and tetraglycosylceramides from High Five cells: identification of a novel (non-arthro-series) glycosphingolipid pathway. Glycobiology 2005; 15:1286-301. [PMID: 16014747 DOI: 10.1093/glycob/cwj011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The major neutral glycosphingolipids (GSLs) of High Five insect cells have been extracted, purified, and characterized. It was anticipated that GSLs from High Five cells would follow the arthro-series pathway, known to be expressed by both insects and nematodes at least through the common tetraglycosylceramide (Glcbeta1Cer --> Manbeta4Glcbeta1Cer [MacCer] --> GlcNAcbeta3Manbeta4Glcbeta1Cer [At(3)Cer] --> GalNAcbeta4- GlcNAcbeta3Manbeta4Glcbeta1Cer [At(4)Cer]). Surprisingly, the structures of the major neutral High Five GSLs already diverge from the arthro-series pathway at the level of the triglycosylceramide. Studies by one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization mass spectrometry (ESI-MS) showed the structure of the predominant High Five triglycosylceramide to be Galbeta3Manbeta4Glcbeta1Cer, whereas the predominant tetraglycosylceramide was characterized as GalNAcalpha4Galbeta3Manbeta4- Glcbeta1Cer. Both of these structures are novel products for any cell or organism so far studied. The GalNAcalpha4 and Galbeta3 units are found in insect GSLs, but always as the fifth and sixth residues linked to GalNAcbeta4 in the arthro-series penta- and hexaglycosylceramide structures (At(5)Cer and At(6)Cer, respectively). The structure of the High Five tetraglycosylceramide thus requires a reversal of the usual order of action of the glycosyltransferases adding the GalNAcalpha4 and Galbeta3 residues in dipteran GSL biosynthesis and implies the existence of an insect Galbeta3-T capable of using Manbeta4Glcbeta1Cer as a substrate with high efficiency. The results demonstrate the potential appearance of unexpected glycoconjugate biosynthetic products even in widely used but unexamined systems, as well as a potential for core switching based on MacCer, as observed in mammalian cells based on the common LacCer intermediate.
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Affiliation(s)
- Matthew D Fuller
- Department of Biology, Georgia Institute of Technology, 309 Cherry Emerson Building, Atlanta, GA 30332-0230, USA
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35
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Abstract
From observations on human diseases and mutant mice, it has become clear that glycosylation plays a major role in metazoan development. Caenorhabditis elegans provides powerful tools to study this problem that are not available in men or mice. The worm has many genes homologous to mammalian genes involved in glycosylation. Glycobiologists have, in recent years, cloned and expressed some of these genes and studied the effects of mutations on worm development. Recent studies have focused on N-glycosylation, lumenal nucleoside diphosphatases, the resistance of C. elegans to a bacterial toxin and infections, fucosylation and proteoglycans.
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Affiliation(s)
- Harry Schachter
- Program in Structural Biology and Biochemistry, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
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36
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Mucha J, Domlatil J, Lochnit G, Rendić D, Paschinger K, HINTERKöRNER G, Hofinger A, Kosma P, Wilson I. The Drosophila melanogaster homologue of the human histo-blood group Pk gene encodes a glycolipid-modifying alpha1,4-N-acetylgalactosaminyltransferase. Biochem J 2005; 382:67-74. [PMID: 15130086 PMCID: PMC1133916 DOI: 10.1042/bj20040535] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Revised: 04/29/2004] [Accepted: 05/07/2004] [Indexed: 11/17/2022]
Abstract
Insects express arthro-series glycosphingolipids, which contain an alpha1,4-linked GalNAc residue. To determine the genetic basis for this linkage, we cloned a cDNA (CG17223) from Drosophila melanogaster encoding a protein with homology to mammalian alpha1,4-glycosyltransferases and expressed it in the yeast Pichia pastoris. Culture supernatants from the transformed yeast were found to display a novel UDP-GalNAc:GalNAcbeta1,4GlcNAcbeta1-R alpha-N-acetylgalactosaminyltransferase activity when using either a glycolipid, p-nitrophenylglycoside or an N-glycan carrying one or two terminal beta-N-acetylgalactosamine residues. NMR and MS in combination with glycosidase digestion and methylation analysis indicate that the cloned cDNA encodes an alpha1,4-N-acetylgalactosaminyltransferase. We hypothesize that this enzyme and its orthologues in other insects are required for the biosynthesis of the N5a and subsequent members of the arthro-series of glycolipids as well as of N-glycan receptors for Bacillus thuringiensis crystal toxin Cry1Ac.
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Affiliation(s)
- Ján Mucha
- *Chemický ústav, Slovenská akadémia vied, Dúbravská cesta 9, 845 38 Bratislava, Slovakia
| | - Jiří Domlatil
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Günter Lochnit
- ‡Institut für Biochemie, Justus-Liebig-Universität Giessen, Friedrichstrasse 24, D-35392 Giessen, Germany
| | - Dubravko Rendić
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Katharina Paschinger
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Georg HINTERKöRNER
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Andreas Hofinger
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Paul Kosma
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
| | - Iain B. H. Wilson
- †Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria
- To whom correspondence should be addressed (email )
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37
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Abstract
Sphingosines, or sphingoids, are a family of naturally occurring long-chain hydrocarbon derivatives sharing a common 1,3-dihydroxy-2-amino-backbone motif. The majority of sphingolipids, as their derivatives are collectively known, can be found in cell membranes in the form of amphiphilic conjugates, each composed of a polar head group attached to an N-acylated sphingoid, or ceramide. Glycosphingolipids (GSLs), which are the glycosides of either ceramide or myo-inositol-(1-O)-phosphoryl-(O-1)-ceramide, are a structurally and functionally diverse sphingolipid subclass; GSLs are ubiquitously distributed among all eukaryotic species and are found in some bacteria. Since GSLs are secondary metabolites, direct and comprehensive analysis (metabolomics) must be considered an essential complement to genomic and proteomic approaches for establishing the structural repertoire within an organism and deducing its possible functional roles. The glycosphingolipidome clearly comprises an important and extensive subset of both the glycome and the lipidome, but the complexities of GSL structure, biosynthesis, and function form the outlines of a considerable analytical problem, especially since their structural diversity confers by extension an enormous variability with respect to physicochemical properties. This chapter covers selected developments and applications of techniques in mass spectrometric (MS) that have contributed to GSL structural analysis and glycosphingolipidomics since 1990. Sections are included on basic characteristics of ionization and fragmentation of permethylated GSLs and of lithium-adducted nonderivatized GSLs under positive-ion electrospray ionization mass spectrometry (ESI-MS) and collision-induced mass spectrometry (CID-MS) conditions; on the analysis of sulfatides, mainly using negative-ion techniques; and on selected applications of ESI-MS and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to emerging GSL structural, functional, and analytical issues. The latter section includes a particular focus on evolving techniques for analysis of gangliosides, GSLs containing sialic acid, as well as on characterizations of GSLs from selected nonmammalian eukaryotes, such as dipterans, nematodes, cestodes, and fungi. Additional sections focus on the issue of whether it is better to leave GSLs intact or remove the ceramide; on development and uses of thin-layer chromatography (TLC) blotting and TLC-MS techniques; and on emerging issues of high-throughput analysis, including the use of flow injection, liquid chromatography mass spectrometry (LC-MS), and capillary electrophoresis mass spectrometry (CE-MS).
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Affiliation(s)
- Steven B Levery
- Department of Chemistry, University of New Hamphsire, Durham, USA
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38
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Horne-Badovinac S, Bilder D. Mass transit: Epithelial morphogenesis in theDrosophila egg chamber. Dev Dyn 2005; 232:559-74. [PMID: 15704134 DOI: 10.1002/dvdy.20286] [Citation(s) in RCA: 218] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Epithelial cells use a striking array of morphogenetic behaviors to sculpt organs and body plans during development. Although it is clear that epithelial morphogenesis is largely driven by cytoskeletal rearrangements and changes in cell adhesion, little is known about how these processes are coordinated to construct complex biological structures from simple sheets of cells. The follicle cell epithelium of the Drosophila egg chamber exhibits a diverse range of epithelial movements in a genetically accessible tissue, making it an outstanding system for the study of epithelial morphogenesis. In this review, we move chronologically through the process of oogenesis, highlighting the dynamic movements of the follicle cells. We discuss the cellular architecture and patterning events that set the stage for morphogenesis, detail individual cellular movements, and focus on current knowledge of the cellular processes that drive follicle cell behavior.
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Affiliation(s)
- Sally Horne-Badovinac
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720-3200, USA
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39
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Wandall HH, Pizette S, Pedersen JW, Eichert H, Levery SB, Mandel U, Cohen SM, Clausen H. Egghead and brainiac are essential for glycosphingolipid biosynthesis in vivo. J Biol Chem 2004; 280:4858-63. [PMID: 15611100 DOI: 10.1074/jbc.c400571200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Drosophila genes, brainiac and egghead, encode glycosyltransferases predicted to act sequentially in early steps of glycosphingolipid biosynthesis, and both genes are required for development in Drosophila. egghead encodes a beta4-mannosyltransferase, and brainiac encodes a beta3-N-acetylglucosaminyltransferase predicted by in vitro analysis to control synthesis of the glycosphingolipid core structure, GlcNAcbeta1-3Manbeta1-4Glcbeta1-Cer, found widely in invertebrates but not vertebrates. In this report we present direct in vivo evidence for this hypothesis. egghead and brainiac mutants lack elongated glycosphingolipids and exhibit accumulation of the truncated precursor glycosphingolipids. Furthermore, we demonstrate that despite fundamental differences in the core structure of mammalian and Drosophila glycosphingolipids, the Drosophila egghead mutant can be rescued by introduction of the mammalian lactosylceramide glycosphingolipid biosynthetic pathway (Galbeta1-4Glcbeta1-Cer) using a human beta4-galactosyltransferase (beta4Gal-T6) transgene. Conversely, introduction of egghead in vertebrate cells (Chinese hamster ovary) resulted in near complete blockage of biosynthesis of glycosphingolipids and accumulation of Manbeta1-4Glcbeta1-Cer. The study demonstrates that glycosphingolipids are essential for development of complex organisms and suggests that the function of the Drosophila glycosphingolipids in development does not depend on the core structure.
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Affiliation(s)
- Hans H Wandall
- Faculty of Health Sciences, University of Copenhagen, Nørre Allé 20, 2200 Copenhagen N, Denmark
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40
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Haines N, Irvine KD. Functional analysis of Drosophila beta1,4-N-acetlygalactosaminyltransferases. Glycobiology 2004; 15:335-46. [PMID: 15563714 DOI: 10.1093/glycob/cwi017] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Members of the mammalian beta1,4-galactosyltransferase family are among the best studied glycosyltransferases, but the requirements for all members of this family within an animal have not previously been determined. Here, we describe analysis of two Drosophila genes, beta4GalNAcTA (CG8536) and beta4GalNAcTB (CG14517), that are homologous to mammalian beta1,4-galactosyltransferases. Like their mammalian homologs, these glycosyltransferases use N-acetylglucosamine as an acceptor substrate. However, they transfer N-acetylgalactosamine rather than galactose. This activity, together with amino acid sequence similarity, places them among a group of recently identified invertebrate beta1,4-N-acetylgalactosaminyltransferases. To investigate the biological functions of these genes, null mutations were generated by imprecise excision of a transposable element (beta4GalNAcTA) or by gene-targeted homologous recombination (beta4GalNAcTB). Flies mutant for beta4GalNAcTA are viable and fertile but display behavioral phenotypes suggestive of essential roles for GalNAc-beta1,4-GlcNAc containing glycoconjugates in neuronal and/or muscular function. beta4GalNAcTB mutants are viable and display no evident morphological or behavioral phenotypes. Flies doubly mutant for both genes display only the behavioral phenotypes associated with mutation of beta4GalNAcTA. Thus Drosophila homologs of the mammalian beta4GalT family are essential for neuromuscular physiology or development but are not otherwise required for viability, fertility, or external morphology.
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Affiliation(s)
- Nicola Haines
- Howard Hughes Medical Institute, Waksman Institute, and Department of Molecular Biology and Biochemistry, Rutgers The State University of New Jersey, Piscataway NJ 08854, USA
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41
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Abstract
Researchers have long predicted that complex carbohydrates on cell surfaces would play important roles in developmental processes because of the observation that specific carbohydrate structures appear in specific spatial and temporal patterns throughout development. The astounding number and complexity of carbohydrate structures on cell surfaces added support to the concept that glycoconjugates would function in cellular communication during development. Although the structural complexity inherent in glycoconjugates has slowed advances in our understanding of their functions, the complete sequencing of the genomes of organisms classically used in developmental studies (e.g., mice, Drosophila melanogaster, and Caenorhabditis elegans) has led to demonstration of essential functions for a number of glycoconjugates in developmental processes. Here we present a review of recent studies analyzing function of a variety of glycoconjugates (O-fucose, O-mannose, N-glycans, mucin-type O-glycans, proteoglycans, glycosphingolipids), focusing on lessons learned from human disease and genetic studies in mice, D. melanogaster, and C. elegans.
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Affiliation(s)
- Robert S Haltiwanger
- Department of Biochemistry and Cell Biology, Institute for Cell and Developmental Biology, State University of New York, Stony Brook, New York 11794-5215, USA.
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42
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Kohyama-Koganeya A, Sasamura T, Oshima E, Suzuki E, Nishihara S, Ueda R, Hirabayashi Y. Drosophila glucosylceramide synthase: a negative regulator of cell death mediated by proapoptotic factors. J Biol Chem 2004; 279:35995-6002. [PMID: 15210713 DOI: 10.1074/jbc.m400444200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glucosylceramide synthase (GlcT-1) catalyzes the formation of glucosylceramide (GlcCer), the core structure of major glycosphingolipids (GSLs), from ceramide and UDP-glucose. Ceramide and its metabolites, such as sphingosine-1-phosphate, are now known to be important mediators of apoptosis and cell survival. Recently, we have shown that GlcT-1 functions to regulate intracellular ceramide levels via glycosylation of ceramide. In this study, we employ the fruit fly Drosophila melanogaster as a model system for understanding the in vivo roles of GlcT-1. We isolated and characterized a GlcT-1 homologue (DGlcT-1) from Drosophila. When DGlcT-1 was expressed in GM-95 cells deficient in GSLs (because of the absence of GlcT-1 activity), these cells regained the ability to synthesize GSLs. Northern blot and in situ hybridization analyses revealed that the expression of DGlcT-1 mRNA was ubiquitous throughout development, suggesting that DGlcT-1 is important for development and differentiation. Indeed, RNA interference experiments demonstrated that the loss of GlcT-1 function enhances apoptotic cell death. Conversely, targeted expression of GlcT-1 partially rescued cell death caused by the proapoptotic factors Reaper and Grim, suggesting that ceramide generation might be one signal pathway that executes the cell death program. We also found that GlcT-1 localized not only in the Golgi apparatus but also in the perinuclear endoplasmic reticulum, providing the first visual evidence of GlcT-1 in membranes. These results indicate that GlcT-1 might down-regulate ceramide generated in these membranes.
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Affiliation(s)
- Ayako Kohyama-Koganeya
- Neuronal Circuit Mechanisms Research Group, Brain Science Institute, The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198, Japan
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Griffitts JS, Huffman DL, Whitacre JL, Barrows BD, Marroquin LD, Müller R, Brown JR, Hennet T, Esko JD, Aroian RV. Resistance to a bacterial toxin is mediated by removal of a conserved glycosylation pathway required for toxin-host interactions. J Biol Chem 2003; 278:45594-602. [PMID: 12944392 DOI: 10.1074/jbc.m308142200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Crystal (Cry) proteins made by the bacterium Bacillus thuringiensis are pore-forming toxins that specifically target insects and nematodes and are used around the world to kill insect pests. To better understand how pore-forming toxins interact with their host, we have screened for Caenorhabditis elegans mutants that resist Cry protein intoxication. We find that Cry toxin resistance involves the loss of two glycosyltransferase genes, bre-2 and bre-4. These glycosyltransferases function in the intestine to confer susceptibility to toxin. Furthermore, they are required for the interaction of active toxin with intestinal cells, suggesting they make an oligosaccharide receptor for toxin. Similarly, the bre-3 resistance gene is also required for toxin interaction with intestinal cells. Cloning of the bre-3 gene indicates it is the C. elegans homologue of the Drosophila egghead (egh) gene. This identification is striking given that the previously identified bre-5 has homology to Drosophila brainiac (brn) and that egh-brn likely function as consecutive glycosyltransferases in Drosophila epithelial cells. We find that, like in Drosophila, bre-3 and bre-5 act in a single pathway in C. elegans. bre-2 and bre-4 are also part of this pathway, thereby extending it. Consistent with its homology to brn, we demonstrate that C. elegans bre-5 rescues the Drosophila brn mutant and that BRE-5 encodes the dominant UDP-GlcNAc:Man GlcNAc transferase activity in C. elegans. Resistance to Cry toxins has uncovered a four component glycosylation pathway that is functionally conserved between nematodes and insects and that provides the basis of the dominant mechanism of resistance in C. elegans.
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Affiliation(s)
- Joel S Griffitts
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA
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