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Kitamata M, Otake Y, Kitagori H, Zhang X, Maki Y, Boku R, Takeuchi M, Nakagoshi H. Functional opsin patterning for Drosophila color vision is established through signaling pathways in adjacent object-detection neurons. Development 2024; 151:dev202388. [PMID: 38421315 PMCID: PMC10984275 DOI: 10.1242/dev.202388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/22/2024] [Indexed: 03/02/2024]
Abstract
Vision is mainly based on two different tasks, object detection and color discrimination, carried out by photoreceptor (PR) cells. The Drosophila compound eye consists of ∼800 ommatidia. Every ommatidium contains eight PR cells, six outer cells (R1-R6) and two inner cells (R7 and R8), by which object detection and color vision are achieved, respectively. Expression of opsin genes in R7 and R8 is highly coordinated through the instructive signal from R7 to R8, and two major ommatidial subtypes are distributed stochastically; pale type expresses Rh3/Rh5 and yellow type expresses Rh4/Rh6 in R7/R8. The homeodomain protein Defective proventriculus (Dve) is expressed in yellow-type R7 and in six outer PRs, and it is involved in Rh3 repression to specify the yellow-type R7. dve mutant eyes exhibited atypical coupling, Rh3/Rh6 and Rh4/Rh5, indicating that Dve activity is required for proper opsin coupling. Surprisingly, Dve activity in R1 is required for the instructive signal, whereas activity in R6 and R7 blocks the signal. Our results indicate that functional coupling of two different neurons is established through signaling pathways from adjacent neurons that are functionally different.
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Affiliation(s)
- Manabu Kitamata
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Yoshiaki Otake
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hideaki Kitagori
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Xuanshuo Zhang
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Yusuke Maki
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Rika Boku
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Masato Takeuchi
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hideki Nakagoshi
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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Tello JA, Williams HE, Eppler RM, Steinhilb ML, Khanna M. Animal Models of Neurodegenerative Disease: Recent Advances in Fly Highlight Innovative Approaches to Drug Discovery. Front Mol Neurosci 2022; 15:883358. [PMID: 35514431 PMCID: PMC9063566 DOI: 10.3389/fnmol.2022.883358] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 03/21/2022] [Indexed: 12/22/2022] Open
Abstract
Neurodegenerative diseases represent a formidable challenge to global health. As advances in other areas of medicine grant healthy living into later decades of life, aging diseases such as Alzheimer's disease (AD) and other neurodegenerative disorders can diminish the quality of these additional years, owed largely to the lack of efficacious treatments and the absence of durable cures. Alzheimer's disease prevalence is predicted to more than double in the next 30 years, affecting nearly 15 million Americans, with AD-associated costs exceeding $1 billion by 2050. Delaying onset of AD and other neurodegenerative diseases is critical to improving the quality of life for patients and reducing the burden of disease on caregivers and healthcare systems. Significant progress has been made to model disease pathogenesis and identify points of therapeutic intervention. While some researchers have contributed to our understanding of the proteins and pathways that drive biological dysfunction in disease using in vitro and in vivo models, others have provided mathematical, biophysical, and computational technologies to identify potential therapeutic compounds using in silico modeling. The most exciting phase of the drug discovery process is now: by applying a target-directed approach that leverages the strengths of multiple techniques and validates lead hits using Drosophila as an animal model of disease, we are on the fast-track to identifying novel therapeutics to restore health to those impacted by neurodegenerative disease.
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Affiliation(s)
- Judith A. Tello
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
| | - Haley E. Williams
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
| | - Robert M. Eppler
- Department of Biology, Central Michigan University, Mount Pleasant, MI, United States
| | - Michelle L. Steinhilb
- Department of Biology, Central Michigan University, Mount Pleasant, MI, United States
| | - May Khanna
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, United States
- Center of Innovation in Brain Science, Tucson, AZ, United States
- Department of Molecular Pathobiology, New York University, New York, NY, United States
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3
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Girard V, Jollivet F, Knittelfelder O, Celle M, Arsac JN, Chatelain G, Van den Brink DM, Baron T, Shevchenko A, Kühnlein RP, Davoust N, Mollereau B. Abnormal accumulation of lipid droplets in neurons induces the conversion of alpha-Synuclein to proteolytic resistant forms in a Drosophila model of Parkinson's disease. PLoS Genet 2021; 17:e1009921. [PMID: 34788284 PMCID: PMC8635402 DOI: 10.1371/journal.pgen.1009921] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 12/01/2021] [Accepted: 11/02/2021] [Indexed: 11/18/2022] Open
Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder characterized by alpha-synuclein (αSyn) aggregation and associated with abnormalities in lipid metabolism. The accumulation of lipids in cytoplasmic organelles called lipid droplets (LDs) was observed in cellular models of PD. To investigate the pathophysiological consequences of interactions between αSyn and proteins that regulate the homeostasis of LDs, we used a transgenic Drosophila model of PD, in which human αSyn is specifically expressed in photoreceptor neurons. We first found that overexpression of the LD-coating proteins Perilipin 1 or 2 (dPlin1/2), which limit the access of lipases to LDs, markedly increased triacylglyclerol (TG) loaded LDs in neurons. However, dPlin-induced-LDs in neurons are independent of lipid anabolic (diacylglycerol acyltransferase 1/midway, fatty acid transport protein/dFatp) and catabolic (brummer TG lipase) enzymes, indicating that alternative mechanisms regulate neuronal LD homeostasis. Interestingly, the accumulation of LDs induced by various LD proteins (dPlin1, dPlin2, CG7900 or KlarsichtLD-BD) was synergistically amplified by the co-expression of αSyn, which localized to LDs in both Drosophila photoreceptor neurons and in human neuroblastoma cells. Finally, the accumulation of LDs increased the resistance of αSyn to proteolytic digestion, a characteristic of αSyn aggregation in human neurons. We propose that αSyn cooperates with LD proteins to inhibit lipolysis and that binding of αSyn to LDs contributes to the pathogenic misfolding and aggregation of αSyn in neurons. Parkinson’s disease (PD) is a neurodegenerative disease characterized by the neurotoxic aggregation of the alpha-synuclein (αSyn) protein. Cellular models of the disease are also associated with an abnormal fat storage in the form of lipid droplets (LDs). However, in which cells, neuron or glial cells, LDs accumulate in the organism remains unknown. To understand the relationship between αSyn and the accumulation of LDs, we used a Drosophila (fruit fly) model of PD. We found that, in the presence of a protein that coats LDs, perilipin, LDs accumulate in photoreceptor neurons of the fly. Interestingly, the accumulation of LDs induced by perilipin or other LD-coating proteins was enhanced in the presence of αSyn. Using human neuronal cell lines and the fly, we could show that LD-coating and αSyn proteins localize at the surface of LDs. Finally, we observed that the process of αSyn aggregation was enhanced in the presence of LDs by using a biochemical approach. We thus propose that the association of αSyn with LDs could contribute to αSyn aggregation and progression of the pathology.
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Affiliation(s)
- Victor Girard
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
| | - Florence Jollivet
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
| | - Oskar Knittelfelder
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Marion Celle
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
| | - Jean-Noel Arsac
- Neurodegenerative Disease Unit; French Agency for Food, Environmental and Occupational Health & Safety Laboratory (Anses) of Lyon, University of Lyon, Lyon, France
| | - Gilles Chatelain
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
| | - Daan M. Van den Brink
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
- Plant Systems Physiology, Radboud Institute for Biological and Environmental Sciences, Radboud University, Nijmegen, The Netherlands
| | - Thierry Baron
- Neurodegenerative Disease Unit; French Agency for Food, Environmental and Occupational Health & Safety Laboratory (Anses) of Lyon, University of Lyon, Lyon, France
| | - Andrej Shevchenko
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Ronald P. Kühnlein
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
- Field of Excellence BioHealth—University of Graz, Graz, Austria
| | - Nathalie Davoust
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
- * E-mail: (ND); (BM)
| | - Bertrand Mollereau
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, University of Lyon, Lyon, France
- * E-mail: (ND); (BM)
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4
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Domingos PM, Jenny A, Combie KF, Del Alamo D, Mlodzik M, Steller H, Mollereau B. Regulation of Numb during planar cell polarity establishment in the Drosophila eye. Mech Dev 2019; 160:103583. [PMID: 31678471 DOI: 10.1016/j.mod.2019.103583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/17/2019] [Accepted: 10/29/2019] [Indexed: 01/15/2023]
Abstract
The establishment of planar cell polarity (PCP) in the Drosophila eye requires correct specification of the R3/R4 pair of photoreceptor cells, determined by a Frizzled mediated signaling event that specifies R3 and induces Delta to activate Notch signaling in the neighboring cell, specifying it as R4. Here, we investigated the role of the Notch signaling negative regulator Numb in the specification of R3/R4 fates and PCP establishment in the Drosophila eye. We observed that Numb is transiently upregulated in R3 at the time of R3/R4 specification. This regulation of Numb levels in developing photoreceptors occurs at the post-transcriptional level and is dependent on Dishevelled, an effector of Frizzled signaling, and Lethal Giant Larva. We detected PCP defects in cells homozygous for numb15, but these defects were due to a loss of function mutation in fat (fatQ805⁎) being present in the numb15 chromosome. However, mosaic overexpression of Numb in R4 precursors (only) caused PCP defects and numb loss-of-function alleles had a modifying effect on the defects found in a hypomorphic dishevelled mutation. Our results suggest that Numb levels are upregulated to reinforce the bias of Notch signaling activation in the R3/R4 pair, two post-mitotic cells that are not specified by asymmetric cell division.
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Affiliation(s)
- Pedro M Domingos
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, Oeiras 2780-157, Portugal; Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA.
| | - Andreas Jenny
- Albert Einstein College of Medicine, 1300 Morris Park Avenue, Chanin Building, Room 503, Bronx NY10461, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Keon F Combie
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA
| | - David Del Alamo
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA; European Molecular Biology Organization, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Marek Mlodzik
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Hermann Steller
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA
| | - Bertrand Mollereau
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA; Université de Lyon, ENSL, UCBL, CNRS, LBMC, 46 Allée d'Italie, 69007 Lyon, France.
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5
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Tanaka R, Miyata S, Yamaguchi M, Yoshida H. Role of the smallish gene during Drosophila eye development. Gene 2019; 684:10-19. [DOI: 10.1016/j.gene.2018.10.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/15/2018] [Accepted: 10/19/2018] [Indexed: 02/06/2023]
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6
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Betsch L, Boltz V, Brioudes F, Pontier G, Girard V, Savarin J, Wipperman B, Chambrier P, Tissot N, Benhamed M, Mollereau B, Raynaud C, Bendahmane M, Szécsi J. TCTP and CSN4 control cell cycle progression and development by regulating CULLIN1 neddylation in plants and animals. PLoS Genet 2019; 15:e1007899. [PMID: 30695029 PMCID: PMC6368322 DOI: 10.1371/journal.pgen.1007899] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 02/08/2019] [Accepted: 12/15/2018] [Indexed: 11/30/2022] Open
Abstract
Translationally Controlled Tumor Protein (TCTP) controls growth by regulating the G1/S transition during cell cycle progression. Our genetic interaction studies show that TCTP fulfills this role by interacting with CSN4, a subunit of the COP9 Signalosome complex, known to influence CULLIN-RING ubiquitin ligases activity by controlling CULLIN (CUL) neddylation status. In agreement with these data, downregulation of CSN4 in Arabidopsis and in tobacco cells leads to delayed G1/S transition comparable to that observed when TCTP is downregulated. Loss-of-function of AtTCTP leads to increased fraction of deneddylated CUL1, suggesting that AtTCTP interferes negatively with COP9 function. Similar defects in cell proliferation and CUL1 neddylation status were observed in Drosophila knockdown for dCSN4 or dTCTP, respectively, demonstrating a conserved mechanism between plants and animals. Together, our data show that CSN4 is the missing factor linking TCTP to the control of cell cycle progression and cell proliferation during organ development and open perspectives towards understanding TCTP's role in organ development and disorders associated with TCTP miss-expression.
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Affiliation(s)
- Léo Betsch
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Véronique Boltz
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Florian Brioudes
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Garance Pontier
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Victor Girard
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, Univ Lyon, Lyon, France
| | - Julie Savarin
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Barbara Wipperman
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Pierre Chambrier
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Nicolas Tissot
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Moussa Benhamed
- Institute of Plant Sciences Paris-Saclay (IPS2), CNRS, INRA, University Paris-Sud, University of Evry, University Paris-Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, Orsay, France
| | - Bertrand Mollereau
- Laboratory of Biology and Modelling of the Cell, UMR5239 CNRS/ENS de Lyon, INSERM U1210, UMS 3444 Biosciences Lyon Gerland, Univ Lyon, Lyon, France
| | - Cécile Raynaud
- Institute of Plant Sciences Paris-Saclay (IPS2), CNRS, INRA, University Paris-Sud, University of Evry, University Paris-Diderot, Sorbonne Paris-Cite, University of Paris-Saclay, Orsay, France
| | - Mohammed Bendahmane
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
| | - Judit Szécsi
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, UCB Lyon 1, CNRS, INRA, UMS 3444 Biosciences Lyon Gerland, Ecole Normale Supérieure, Lyon, France
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Robin M, Issa AR, Santos CC, Napoletano F, Petitgas C, Chatelain G, Ruby M, Walter L, Birman S, Domingos PM, Calvi BR, Mollereau B. Drosophila p53 integrates the antagonism between autophagy and apoptosis in response to stress. Autophagy 2018; 15:771-784. [PMID: 30563404 DOI: 10.1080/15548627.2018.1558001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The tumor suppressor TP53/p53 is a known regulator of apoptosis and macroautophagy/autophagy. However, the molecular mechanism by which TP53 regulates 2 apparently incompatible processes remains unknown. We found that Drosophila lacking p53 displayed impaired autophagic flux, higher caspase activation and mortality in response to oxidative stress compared with wild-type flies. Moreover, autophagy and apoptosis were differentially regulated by the p53 (p53B) and ΔNp53 (p53A) isoforms: while the former induced autophagy in differentiated neurons, which protected against cell death, the latter inhibited autophagy by activating the caspases Dronc, Drice, and Dcp-1. Our results demonstrate that the differential use of p53 isoforms combined with the antagonism between apoptosis and autophagy ensures the generation of an appropriate p53 biological response to stress.
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Affiliation(s)
- Marion Robin
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France
| | - Abdul Raouf Issa
- b Genes Circuits Rhythms and Neuropathology , Brain Plasticity Unit, CNRS, ESPCI Paris, Labex Memolife, PSL Research University , Paris , France.,e Department of Life Sciences , University of Trieste c/o CIB National Laboratory , Area Science Park , Trieste , Italy
| | - Cristiana C Santos
- c Instituto de Tecnologia Química e Biológica , Universidade Nova de Lisboa , Oeiras , Portugal
| | - Francesco Napoletano
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France.,e Department of Life Sciences , University of Trieste c/o CIB National Laboratory , Area Science Park , Trieste , Italy
| | - Céline Petitgas
- b Genes Circuits Rhythms and Neuropathology , Brain Plasticity Unit, CNRS, ESPCI Paris, Labex Memolife, PSL Research University , Paris , France
| | - Gilles Chatelain
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France
| | - Mathilde Ruby
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France
| | - Ludivine Walter
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France
| | - Serge Birman
- b Genes Circuits Rhythms and Neuropathology , Brain Plasticity Unit, CNRS, ESPCI Paris, Labex Memolife, PSL Research University , Paris , France
| | - Pedro M Domingos
- c Instituto de Tecnologia Química e Biológica , Universidade Nova de Lisboa , Oeiras , Portugal
| | - Brian R Calvi
- d Department of Biology , Indiana University , Bloomington , IN , USA
| | - Bertrand Mollereau
- a Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland , Lyon , France
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8
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Van Den Brink DM, Cubizolle A, Chatelain G, Davoust N, Girard V, Johansen S, Napoletano F, Dourlen P, Guillou L, Angebault-Prouteau C, Bernoud-Hubac N, Guichardant M, Brabet P, Mollereau B. Physiological and pathological roles of FATP-mediated lipid droplets in Drosophila and mice retina. PLoS Genet 2018; 14:e1007627. [PMID: 30199545 PMCID: PMC6147681 DOI: 10.1371/journal.pgen.1007627] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 09/20/2018] [Accepted: 08/13/2018] [Indexed: 11/18/2022] Open
Abstract
Increasing evidence suggests that dysregulation of lipid metabolism is associated with neurodegeneration in retinal diseases such as age-related macular degeneration and in brain disorders such as Alzheimer’s and Parkinson’s diseases. Lipid storage organelles (lipid droplets, LDs), accumulate in many cell types in response to stress, and it is now clear that LDs function not only as lipid stores but also as dynamic regulators of the stress response. However, whether these LDs are always protective or can also be deleterious to the cell is unknown. Here, we investigated the consequences of LD accumulation on retinal cell homeostasis under physiological and stress conditions in Drosophila and in mice. In wild-type Drosophila, we show that dFatp is required and sufficient for expansion of LD size in retinal pigment cells (RPCs) and that LDs in RPCs are required for photoreceptor survival during aging. Similarly, in mice, LD accumulation induced by RPC-specific expression of human FATP1 was non-toxic and promoted mitochondrial energy metabolism in RPCs and non-autonomously in photoreceptor cells. In contrast, the inhibition of LD accumulation by dFatp knockdown suppressed neurodegeneration in Aats-metFBDrosophila mutants, which carry elevated levels of reactive oxygen species (ROS). This suggests that abnormal turnover of LD may be toxic for photoreceptors cells of the retina under oxidative stress. Collectively, these findings indicate that FATP-mediated LD formation in RPCs promotes RPC and neuronal homeostasis under physiological conditions but could be deleterious for the photoreceptors under pathological conditions. Lipids are major cell constituents and are present in the membranes, as free lipids in the cytoplasm, or stored in vesicles called lipid droplets (LDs). Under conditions of stress, lipids stored in LDs can be released to serve as substrates for energy metabolism by mitochondria. However, lipid storage is dysregulated in many degenerative disorders such as age-related macular degeneration, Parkinson’s and Alzheimer’s diseases. Thus, it is unclear whether accumulation of LDs is protective or toxic for neuronal cells. To address this question, we examined the consequences of removal or enforced LD accumulation on the health of retinal cells in flies and mice. Like humans, fly and mouse retinas contain retinal pigment cells (RPC) that support the functions of neighboring photoreceptor cells. We found that overexpression of the fatty acid transport protein (FATP) in RPCs induced accumulation of LDs in both transgenic flies and mice. Moreover, LD accumulation in RPCs was not harmful for juxtaposed photoreceptors during aging, but was toxic under stress conditions. We propose that lipid storage promotes cellular communication that affects photoreceptor health.
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Affiliation(s)
- Daan M. Van Den Brink
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
| | - Aurélie Cubizolle
- Institut des Neurosciences de Montpellier, INSERM U1051, CHU St Eloi, Montpellier, France
- Université de Montpellier, Montpellier, France
| | - Gilles Chatelain
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
| | - Nathalie Davoust
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
| | - Victor Girard
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
| | - Simone Johansen
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
| | - Francesco Napoletano
- Molecular Oncology Unit, Department of Life Sciences, University of Trieste c/o Laboratorio Nazionale CIB, Area Science Park, Trieste, Italy
| | - Pierre Dourlen
- Institut Pasteur de Lille; Inserm, U1167, RID-AGE-Risk Factors and Molecular Determinants of Aging-Related Diseases; University Lille, U1167-Excellence Laboratory LabEx DISTALZ, Lille, France
| | - Laurent Guillou
- Institut des Neurosciences de Montpellier, INSERM U1051, CHU St Eloi, Montpellier, France
- Université de Montpellier, Montpellier, France
| | - Claire Angebault-Prouteau
- Institut des Neurosciences de Montpellier, INSERM U1051, CHU St Eloi, Montpellier, France
- INSERM U1046, UMR CNRS 9214, Université de Montpellier, CHRU de Montpellier, Montpellier, France
| | - Nathalie Bernoud-Hubac
- Univ Lyon, CarMeN laboratory, INSA Lyon, INSERM U1060, INRA U1397, Université Claude Bernard Lyon 1, F-69621, Villeurbanne, France
| | - Michel Guichardant
- Univ Lyon, CarMeN laboratory, INSA Lyon, INSERM U1060, INRA U1397, Université Claude Bernard Lyon 1, F-69621, Villeurbanne, France
| | - Philippe Brabet
- Institut des Neurosciences de Montpellier, INSERM U1051, CHU St Eloi, Montpellier, France
- Université de Montpellier, Montpellier, France
| | - Bertrand Mollereau
- Université de Lyon, ENSL, UCBL, CNRS, LBMC, UMS 3444 Biosciences Lyon Gerland, Lyon, France
- * E-mail:
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9
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Portela M, Yang L, Paul S, Li X, Veraksa A, Parsons LM, Richardson HE. Lgl reduces endosomal vesicle acidification and Notch signaling by promoting the interaction between Vap33 and the V-ATPase complex. Sci Signal 2018; 11:11/533/eaar1976. [PMID: 29871910 DOI: 10.1126/scisignal.aar1976] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epithelial cell polarity is linked to the control of tissue growth and tumorigenesis. The tumor suppressor and cell polarity protein lethal-2-giant larvae (Lgl) promotes Hippo signaling and inhibits Notch signaling to restrict tissue growth in Drosophila melanogaster Notch signaling is greater in lgl mutant tissue than in wild-type tissue because of increased acidification of endosomal vesicles, which promotes the proteolytic processing and activation of Notch by γ-secretase. We showed that the increased Notch signaling and tissue growth defects of lgl mutant tissue depended on endosomal vesicle acidification mediated by the vacuolar adenosine triphosphatase (V-ATPase). Lgl promoted the activity of the V-ATPase by interacting with Vap33 (VAMP-associated protein of 33 kDa). Vap33 physically and genetically interacted with Lgl and V-ATPase subunits and repressed V-ATPase-mediated endosomal vesicle acidification and Notch signaling. Vap33 overexpression reduced the abundance of the V-ATPase component Vha44, whereas Lgl knockdown reduced the binding of Vap33 to the V-ATPase component Vha68-3. Our data indicate that Lgl promotes the binding of Vap33 to the V-ATPase, thus inhibiting V-ATPase-mediated endosomal vesicle acidification and thereby reducing γ-secretase activity, Notch signaling, and tissue growth. Our findings implicate the deregulation of Vap33 and V-ATPase activity in polarity-impaired epithelial cancers.
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Affiliation(s)
- Marta Portela
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia.,Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Department of Molecular, Cellular and Developmental Neurobiology, Cajal Institute, Avenida Doctor Arce, 37, Madrid 28002, Spain
| | - Liu Yang
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Sayantanee Paul
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Xia Li
- Department of Mathematics and Statistics, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Alexey Veraksa
- Department of Biology, University of Massachusetts, Boston, MA 02125, USA
| | - Linda M Parsons
- Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Helena E Richardson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia. .,Cell Cycle and Development Laboratory, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002, Australia.,Sir Peter MacCallum Department of Oncology, Department of Anatomy and Neuroscience, Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Victoria 3010, Australia
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10
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Dorot O, Steller H, Segal D, Horowitz M. Past1 Modulates Drosophila Eye Development. PLoS One 2017; 12:e0169639. [PMID: 28060904 PMCID: PMC5218476 DOI: 10.1371/journal.pone.0169639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 12/20/2016] [Indexed: 11/24/2022] Open
Abstract
Endocytosis is a multi-step process involving a large number of proteins, both general factors, such as clathrin and adaptor protein complexes, and unique proteins, which modulate specialized endocytic processes, like the EHD proteins. EHDs are a family of Eps15 Homology Domain containing proteins that consists of four mammalian homologs, one C. elegans, one Drosophila melanogaster and two plants orthologs. These membrane-associated proteins are involved in different steps of endocytic trafficking pathways. We have previously shown that the Drosophila EHD ortholog, PAST1, associates predominantly with the plasma membrane. Mutations in Past1 result in defects in endocytosis, male sterility, temperature sensitivity and premature death of the flies. Also, Past1 genetically interacts with Notch. In the present study, we investigated the role of PAST1 in the developing fly eye. In mutant flies lacking PAST1, abnormal differentiation of photoreceptors R1, R6 and R7 was evident, with partial penetrance. Likewise, five cone cells were present instead of four. Expression of transgenic PAST1 resulted in a dominant negative effect, with a phenotype similar to that of the deletion mutant, and appearance of additional inter-ommatidial pigment cells. Our results strongly suggest a role for PAST1 in differentiation of photoreceptors R1/R6/R7 and cone cells of the fly ommatidia.
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Affiliation(s)
- Orly Dorot
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Hermann Steller
- Howard Hughes Medical Institute, Strang Laboratory of Cancer Research, The Rockefeller University, New York, New York, United States of America
| | - Daniel Segal
- Department of Molecular Microbiology and Biotechnology and the Interdisciplinary Sagol School of Neurosciences, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Mia Horowitz
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
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11
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Mollereau B, Rzechorzek NM, Roussel BD, Sedru M, Van den Brink DM, Bailly-Maitre B, Palladino F, Medinas DB, Domingos PM, Hunot S, Chandran S, Birman S, Baron T, Vivien D, Duarte CB, Ryoo HD, Steller H, Urano F, Chevet E, Kroemer G, Ciechanover A, Calabrese EJ, Kaufman RJ, Hetz C. Adaptive preconditioning in neurological diseases - therapeutic insights from proteostatic perturbations. Brain Res 2016; 1648:603-616. [PMID: 26923166 PMCID: PMC5010532 DOI: 10.1016/j.brainres.2016.02.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 02/16/2016] [Indexed: 02/06/2023]
Abstract
In neurological disorders, both acute and chronic neural stress can disrupt cellular proteostasis, resulting in the generation of pathological protein. However in most cases, neurons adapt to these proteostatic perturbations by activating a range of cellular protective and repair responses, thus maintaining cell function. These interconnected adaptive mechanisms comprise a 'proteostasis network' and include the unfolded protein response, the ubiquitin proteasome system and autophagy. Interestingly, several recent studies have shown that these adaptive responses can be stimulated by preconditioning treatments, which confer resistance to a subsequent toxic challenge - the phenomenon known as hormesis. In this review we discuss the impact of adaptive stress responses stimulated in diverse human neuropathologies including Parkinson׳s disease, Wolfram syndrome, brain ischemia, and brain cancer. Further, we examine how these responses and the molecular pathways they recruit might be exploited for therapeutic gain. This article is part of a Special Issue entitled SI:ER stress.
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Affiliation(s)
- B Mollereau
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France.
| | - N M Rzechorzek
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom; Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian EH25 9RG, United Kingdom
| | - B D Roussel
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - M Sedru
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D M Van den Brink
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - B Bailly-Maitre
- INSERM U1065, C3M, Team 8 (Hepatic Complications in Obesity), Nice, France
| | - F Palladino
- Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell, F-69007, Lyon, France
| | - D B Medinas
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile
| | - P M Domingos
- ITQB-UNL, Av. da Republica, EAN, 2780-157 Oeiras, Portugal
| | - S Hunot
- Inserm, U 1127, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France
| | - S Chandran
- Centre for Clinical Brain Sciences, Chancellor's Building, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
| | - S Birman
- Genes Circuits Rhythms and Neuropathology, Brain Plasticity Unit, CNRS UMR 8249, ESPCI ParisTech, PSL Research University, 75005 Paris, France
| | - T Baron
- ANSES, French Agency for Food, Environmental and Occupational Health & Safety, Neurodegenerative Diseases Unit, 31, avenue Tony Garnier, 69364 Lyon Cedex 07, France
| | - D Vivien
- Inserm, UMR-S U919 Serine Proteases and Pathophysiology of the Neurovascular Unit, 14000 Caen, France
| | - C B Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Faculty of Medicine, Rua Larga, and Department of Life Sciences, University of Coimbra, 3004-504 Coimbra, Portugal
| | - H D Ryoo
- Department of Cell Biology, New York University School of Medicine, New York, NY, USA
| | - H Steller
- Howard Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - F Urano
- Washington University School of Medicine, Department of Internal Medicine, St. Louis, MO 63110 USA
| | - E Chevet
- Inserm ERL440 "Oncogenesis, Stress, Signaling", Université de Rennes 1, Rennes, France; Centre de Lutte Contre le Cancer Eugène Marquis, Rennes, France
| | - G Kroemer
- Equipe 11 labellisée par la Ligue contre le Cancer, Centre de Recherche des Cordeliers, Paris, France; Cell Biology and Metabolomics platforms, Gustave Roussy Comprehensive Cancer Center, Villejuif, France; INSERM, U1138, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Université Pierre et Marie Curie, Paris, France; Pôle de Biologie, Hôpital Européen Georges Pompidou, AP-HP, Paris, France; Karolinska Institute, Department of Women׳s and Children׳s Health, Karolinska University Hospital, Stockholm, Sweden
| | - A Ciechanover
- The Polak Cancer and Vascular Biology Research Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology, Haifa 30196, Israel
| | - E J Calabrese
- Department of Environmental Health Sciences, University of Massachusetts, Morrill I, N344, Amherst, MA 01003, USA
| | - R J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - C Hetz
- Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Faculty of Medicine, University of Chile, Santiago, Chile; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA
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12
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Bernardo-Garcia FJ, Fritsch C, Sprecher SG. The transcription factor Glass links eye field specification with photoreceptor differentiation in Drosophila. Development 2016; 143:1413-23. [PMID: 26952983 DOI: 10.1242/dev.128801] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 02/22/2016] [Indexed: 12/12/2022]
Abstract
Eye development requires an evolutionarily conserved group of transcription factors, termed the retinal determination network (RDN). However, little is known about the molecular mechanism by which the RDN instructs cells to differentiate into photoreceptors. We show that photoreceptor cell identity in Drosophila is critically regulated by the transcription factor Glass, which is primarily expressed in photoreceptors and whose role in this process was previously unknown. Glass is both required and sufficient for the expression of phototransduction proteins. Our results demonstrate that the RDN member Sine oculis directly activates glass expression, and that Glass activates the expression of the transcription factors Hazy and Otd. We identified hazy as a direct target of Glass. Induced expression of Hazy in the retina partially rescues the glass mutant phenotype. Together, our results provide a transcriptional link between eye field specification and photoreceptor differentiation in Drosophila, placing Glass at a central position in this developmental process.
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Affiliation(s)
| | - Cornelia Fritsch
- Department of Biology, University of Fribourg, Fribourg 1700, Switzerland
| | - Simon G Sprecher
- Department of Biology, University of Fribourg, Fribourg 1700, Switzerland
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13
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Weiss S, Minke B. A new genetic model for calcium induced autophagy and ER-stress in Drosophila photoreceptor cells. Channels (Austin) 2015; 9:14-20. [PMID: 25664921 DOI: 10.4161/19336950.2014.981439] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cytoplasmic Ca2+ overload is known to trigger autophagy and ER-stress. Furthermore, ER-stress and autophagy are commonly associated with degenerative pathologies, but their role in disease progression is still a matter of debate, in part, owing to limitations of existing animal model systems. The Drosophila eye is a widely used model system for studying neurodegenerative pathologies. Recently, we characterized the Drosophila protein, Calphotin, as a cytosolic immobile Ca2+ buffer, which participates in Ca2+ homeostasis in Drosophila photoreceptor cells. Exposure of calphotin hypomorph flies to continuous illumination, which induces Ca2+ influx into photoreceptor cells, resulted in severe Ca2+-dependent degeneration. Here we show that this degeneration is autophagy and ER-stress related. Our studies thus provide a new model in which genetic manipulations trigger changes in cellular Ca2+ distribution. This model constitutes a framework for further investigations into the link between cytosolic Ca2+, ER-stress and autophagy in human disorders and diseases.
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Affiliation(s)
- Shirley Weiss
- a Department of Medical Neurobiology ; Institute for Medical Research Israel-Canada (IMRIC) and the Edmond and Lily Safra Center for Brain Sciences (ELSC); Faculty of Medicine; The Hebrew University ; Jerusalem , Israel
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14
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Fatty acid transport proteins in disease: New insights from invertebrate models. Prog Lipid Res 2015; 60:30-40. [PMID: 26416577 DOI: 10.1016/j.plipres.2015.08.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 08/18/2015] [Indexed: 11/22/2022]
Abstract
The dysregulation of lipid metabolism has been implicated in various diseases, including diabetes, cardiopathies, dermopathies, retinal and neurodegenerative diseases. Mouse models have provided insights into lipid metabolism. However, progress in the understanding of these pathologies is hampered by the multiplicity of essential cellular processes and genes that modulate lipid metabolism. Drosophila and Caenorhabditis elegans have emerged as simple genetic models to improve our understanding of these metabolic diseases. Recent studies have characterized fatty acid transport protein (fatp) mutants in Drosophila and C. elegans, establishing new models of cardiomyopathy, retinal degeneration, fat storage disease and dermopathies. These models have generated novel insights into the physiological role of the Fatp protein family in vivo in multicellular organisms, and are likely to contribute substantially to progress in understanding the etiology of various metabolic disorders. Here, we describe and discuss the mechanisms underlying invertebrate fatp mutant models in the light of the current knowledge relating to FATPs and lipid disorders in vertebrates.
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15
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Querenet M, Goubard V, Chatelain G, Davoust N, Mollereau B. Spen is required for pigment cell survival during pupal development in Drosophila. Dev Biol 2015; 402:208-15. [PMID: 25872184 DOI: 10.1016/j.ydbio.2015.03.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Revised: 03/19/2015] [Accepted: 03/22/2015] [Indexed: 01/25/2023]
Abstract
Apoptosis is required during development to eliminate superfluous cells and sculpt tissues; spatial and timed control of apoptosis ensures that the necessary number of cells is eliminated at a precise time in a given tissue. The elimination of supernumerary pigment or inter-ommatidial cells (IOCs) depends on cell-cell communication and is necessary for the formation of the honeycomb-like structure of the Drosophila eye. However, the mechanisms occurring during pupal development and controlling apoptosis of superfluous IOC in space and time remain unclear. Here, we found that split-ends (spen) is required for IOC survival at the time of removal of superfluous IOCs. Loss of spen function leads to abnormal removal of IOCs by apoptosis. We show that spen is required non-autonomously in cone cells for the survival of IOCs by positively regulating the Spitz/EGFR pathway. We propose that Spen is an important survival factor that ensures spatial control of the apoptotic wave that is necessary for the correct patterning and formation of the Drosophila eye.
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Affiliation(s)
- Matthieu Querenet
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
| | - Valerie Goubard
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
| | - Gilles Chatelain
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
| | - Nathalie Davoust
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France.
| | - Bertrand Mollereau
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 3444 Biosciences Lyon Gerland, Université de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France.
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16
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Mahato S, Morita S, Tucker AE, Liang X, Jackowska M, Friedrich M, Shiga Y, Zelhof AC. Common transcriptional mechanisms for visual photoreceptor cell differentiation among Pancrustaceans. PLoS Genet 2014; 10:e1004484. [PMID: 24991928 PMCID: PMC4084641 DOI: 10.1371/journal.pgen.1004484] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 05/16/2014] [Indexed: 12/27/2022] Open
Abstract
A hallmark of visual rhabdomeric photoreceptors is the expression of a rhabdomeric opsin and uniquely associated phototransduction molecules, which are incorporated into a specialized expanded apical membrane, the rhabdomere. Given the extensive utilization of rhabdomeric photoreceptors in the eyes of protostomes, here we address whether a common transcriptional mechanism exists for the differentiation of rhabdomeric photoreceptors. In Drosophila, the transcription factors Pph13 and Orthodenticle (Otd) direct both aspects of differentiation: rhabdomeric opsin transcription and rhabdomere morphogenesis. We demonstrate that the orthologs of both proteins are expressed in the visual systems of the distantly related arthropod species Tribolium castaneum and Daphnia magna and that their functional roles are similar in these species. In particular, we establish that the Pph13 homologs have the ability to bind a subset of Rhodopsin core sequence I sites and that these sites are present in key phototransduction genes of both Tribolium and Daphnia. Furthermore, Pph13 and Otd orthologs are capable of executing deeply conserved functions of photoreceptor differentiation as evidenced by the ability to rescue their respective Drosophila mutant phenotypes. Pph13 homologs are equivalent in their ability to direct both rhabdomere morphogenesis and opsin expression within Drosophila, whereas Otd paralogs demonstrate differential abilities to regulate photoreceptor differentiation. Finally, loss-of-function analyses in Tribolium confirm the conserved requirement of Pph13 and Otd in regulating both rhabdomeric opsin transcription and rhabdomere morphogenesis. Taken together, our data identify components of a regulatory framework for rhabdomeric photoreceptor differentiation in Pancrustaceans, providing a foundation for defining ancestral regulatory modules of rhabdomeric photoreceptor differentiation. Visual systems are populated by one of two fundamental types of photoreceptors, ciliary and rhabdomeric. Each photoreceptor type is defined by the opsin molecule expressed and the final morphological form adapted to house the phototransduction machinery. Here we address whether a common transcriptional mechanisms exists for the differentiation of rhabdomeric photoreceptors. We demonstrate that orthologs of two Drosophila (fruit fly) transcription factors, Pph13 and Orthodenticle, are expressed in photoreceptors of Pancrustaceans, Tribolium (red flour beetle) and Daphnia (water flea), and are capable of executing conserved functions of rhabdomeric photoreceptor differentiation. In particular, Tribolium and Daphnia orthologs are capable of substituting and rescuing the photoreceptor differentiation defects observed in their corresponding Drosophila mutants. Furthermore, loss of function analysis in Tribolium of both Pph13 and orthodenticle genes demonstrate they regulate opsin transcription and morphogenesis of the photoreceptor apical membrane. Our data illuminate a framework for rhabdomeric photoreceptor differentiation and provide the foundation for defining the ancestral regulatory modules for rhabdomeric differentiation and potential modifications that underlie the functional diversity observed in rhabdomeric photoreceptors.
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Affiliation(s)
- Simpla Mahato
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
| | - Shinichi Morita
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Abraham E. Tucker
- Department of Biology, Southern Arkansas University, Magnolia, Arkansas, United States of America
| | - Xulong Liang
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
| | - Magdalena Jackowska
- Department of Biological Sciences, Wayne State University, Detroit, Michigan, United States of America
| | - Markus Friedrich
- Department of Biological Sciences, Wayne State University, Detroit, Michigan, United States of America
- Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, Michigan, United States of America
| | - Yasuhiro Shiga
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan
| | - Andrew C. Zelhof
- Department of Biology, Indiana University, Bloomington, Indiana, United States of America
- * E-mail:
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17
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Dourlen P, Levet C, Mejat A, Gambis A, Mollereau B. The Tomato/GFP-FLP/FRT method for live imaging of mosaic adult Drosophila photoreceptor cells. J Vis Exp 2013:e50610. [PMID: 24084155 PMCID: PMC3923918 DOI: 10.3791/50610] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The Drosophila eye is widely used as a model for studies of development and neuronal degeneration. With the powerful mitotic recombination technique, elegant genetic screens based on clonal analysis have led to the identification of signaling pathways involved in eye development and photoreceptor (PR) differentiation at larval stages. We describe here the Tomato/GFP-FLP/FRT method, which can be used for rapid clonal analysis in the eye of living adult Drosophila. Fluorescent photoreceptor cells are imaged with the cornea neutralization technique, on retinas with mosaic clones generated by flipase-mediated recombination. This method has several major advantages over classical histological sectioning of the retina: it can be used for high-throughput screening and has proved an effective method for identifying the factors regulating PR survival and function. It can be used for kinetic analyses of PR degeneration in the same living animal over several weeks, to demonstrate the requirement for specific genes for PR survival or function in the adult fly. This method is also useful for addressing cell autonomy issues in developmental mutants, such as those in which the establishment of planar cell polarity is affected.
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Affiliation(s)
- Pierre Dourlen
- Laboratory of Molecular Biology of the Cell, Ecole Normale Supérieure de Lyon
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18
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Das S, Chen QB, Saucier JD, Drescher B, Zong Y, Morgan S, Forstall J, Meriwether A, Toranzo R, Leal SM. The Drosophila T-box transcription factor Midline functions within the Notch-Delta signaling pathway to specify sensory organ precursor cell fates and regulates cell survival within the eye imaginal disc. Mech Dev 2013; 130:577-601. [PMID: 23962751 DOI: 10.1016/j.mod.2013.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 07/30/2013] [Accepted: 08/03/2013] [Indexed: 12/20/2022]
Abstract
We report that the T-box transcription factor Midline (Mid), an evolutionary conserved homolog of the vertebrate Tbx20 protein, functions within the Notch-Delta signaling pathway essential for specifying the fates of sensory organ precursor (SOP) cells. These findings complement an established history of research showing that Mid regulates the cell-fate specification of diverse cell types within the developing heart, epidermis and central nervous system. Tbx20 has been detected in unique neuronal and epithelial cells of embryonic eye tissues in both mice and humans. However, the mechanisms by which either Mid or Tbx20 function to regulate cell-fate specification or other critical aspects of eye development including cell survival have not yet been elucidated. We have also gathered preliminary evidence suggesting that Mid may play an indirect, but vital role in selecting SOP cells within the third-instar larval eye disc by regulating the expression of the proneural gene atonal. During subsequent pupal stages, Mid specifies SOP cell fates as a member of the Notch-Delta signaling hierarchy and is essential for maintaining cell viability by inhibiting apoptotic pathways. We present several new hypotheses that seek to understand the role of Mid in regulating developmental processes downstream of the Notch receptor that are critical for specifying unique cell fates, patterning the adult eye and maintaining cellular homeostasis during eye disc morphogenesis.
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Affiliation(s)
- Sudeshna Das
- The Department of Biological Sciences, University of Southern Mississippi, United States
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19
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Mora N, Santa Bárbara Ruiz P, Ferreira N, Serras F. Ras signal triggers β-amyloid precursor protein (APP) expression. Small GTPases 2013; 4:171-3. [PMID: 23648941 DOI: 10.4161/sgtp.24768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
It has recently been discovered that the Drosophila β-amyloid protein precursor like (Appl) gene, the ortholog of the human β-Amyloid Precursor Protein (APP) gene, is transcriptionally activated by receptor tyrosine kinase activity that involves Ras/MAPK signaling in vivo. This regulation is specifically controlled in photoreceptor neurons of the Drosophila retina. This suggests that some cases of Alzheimer disease, those which have been associated with high expression of the APP gene, may involve Ras signal transduction.
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Affiliation(s)
- Natalia Mora
- Departament de Genètica; Facultat de Biologia; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona; Barcelona, Spain; Laboratory of Neurogenetics; Department of Molecular and Developmental Genetics; VIB; Leuven, Belgium
| | - Paula Santa Bárbara Ruiz
- Departament de Genètica; Facultat de Biologia; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona; Barcelona, Spain
| | - Nuno Ferreira
- Departament de Genètica; Facultat de Biologia; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona; Barcelona, Spain
| | - Florenci Serras
- Departament de Genètica; Facultat de Biologia; Institut de Biomedicina de la Universitat de Barcelona (IBUB); Universitat de Barcelona; Barcelona, Spain
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Dourlen P, Bertin B, Chatelain G, Robin M, Napoletano F, Roux MJ, Mollereau B. Drosophila fatty acid transport protein regulates rhodopsin-1 metabolism and is required for photoreceptor neuron survival. PLoS Genet 2012; 8:e1002833. [PMID: 22844251 PMCID: PMC3405995 DOI: 10.1371/journal.pgen.1002833] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 06/05/2012] [Indexed: 01/16/2023] Open
Abstract
Tight regulation of the visual response is essential for photoreceptor function and survival. Visual response dysregulation often leads to photoreceptor cell degeneration, but the causes of such cell death are not well understood. In this study, we investigated a fatty acid transport protein (fatp) null mutation that caused adult-onset and progressive photoreceptor cell death. Consistent with fatp having a role in the retina, we showed that fatp is expressed in adult photoreceptors and accessory cells and that its re-expression in photoreceptors rescued photoreceptor viability in fatp mutants. The visual response in young fatp-mutant flies was abnormal with elevated electroretinogram amplitudes associated with high levels of Rhodopsin-1 (Rh1). Reducing Rh1 levels in rh1 mutants or depriving flies of vitamin A rescued photoreceptor cell death in fatp mutant flies. Our results indicate that fatp promotes photoreceptor survival by regulating Rh1 abundance.
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Affiliation(s)
- Pierre Dourlen
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
- * E-mail: (PD); (BM)
| | - Benjamin Bertin
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - Gilles Chatelain
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - Marion Robin
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - Francesco Napoletano
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
| | - Michel J. Roux
- Translational Medicine and Neurogenetics, IGBMC, UMR7104 CNRS/Université de Strasbourg/Inserm U964, Strasbourg, France
| | - Bertrand Mollereau
- Laboratory of Molecular Biology of the Cell, UMR5239 CNRS/Ecole Normale Supérieure de Lyon, UMS 344 Biosciences Lyon Gerland, Université de Lyon, Lyon, France
- * E-mail: (PD); (BM)
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21
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Sood P, Johnston RJ, Kussell E. Stochastic de-repression of Rhodopsins in single photoreceptors of the fly retina. PLoS Comput Biol 2012; 8:e1002357. [PMID: 22319431 PMCID: PMC3271025 DOI: 10.1371/journal.pcbi.1002357] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 12/05/2011] [Indexed: 11/18/2022] Open
Abstract
The photoreceptors of the Drosophila compound eye are a classical model for studying cell fate specification. Photoreceptors (PRs) are organized in bundles of eight cells with two major types – inner PRs involved in color vision and outer PRs involved in motion detection. In wild type flies, most PRs express a single type of Rhodopsin (Rh): inner PRs express either Rh3, Rh4, Rh5 or Rh6 and outer PRs express Rh1. In outer PRs, the K50 homeodomain protein Dve is a key repressor that acts to ensure exclusive Rh expression. Loss of Dve results in de-repression of Rhodopsins in outer PRs, and leads to a wide distribution of expression levels. To quantify these effects, we introduce an automated image analysis method to measure Rhodopsin levels at the single cell level in 3D confocal stacks. Our sensitive methodology reveals cell-specific differences in Rhodopsin distributions among the outer PRs, observed over a developmental time course. We show that Rhodopsin distributions are consistent with a two-state model of gene expression, in which cells can be in either high or basal states of Rhodopsin production. Our model identifies a significant role of post-transcriptional regulation in establishing the two distinct states. The timescale for interconversion between basal and high states is shown to be on the order of days. Our results indicate that even in the absence of Dve, the Rhodopsin regulatory network can maintain highly stable states. We propose that the role of Dve in outer PRs is to buffer against rare fluctuations in this network. Complex networks of genetic interactions govern the development of multicellular organisms. One of the best-characterized networks governs the development of the fruit-fly retina, a highly organized, three-dimensional organ composed of a hexagonal grid of eight types of photoreceptor neurons. Each photoreceptor responds to a particular wavelength of light depending on the Rhodopsin protein it expresses. We present novel computational methods to quantify cell-specific Rhodopsin levels from confocal microscopy images. We apply these methods to study the effect of the loss of a key repressor that ensures each photoreceptor expresses only one Rhodopsin. We show that this perturbation has cell-specific effects. Our measurement of the cell-type specific Rhodopsin distributions reveals differences between photoreceptor cells, which could not otherwise be detected. Using mathematical models of gene expression, we attribute this variability to stochastic events that activate Rhodopsin production.
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Affiliation(s)
- Pranidhi Sood
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, New York, United States of America
| | - Robert J. Johnston
- Center for Developmental Genetics, Department of Biology, New York University, New York, New York, United States of America
| | - Edo Kussell
- Center for Genomics and Systems Biology, Department of Biology, New York University, New York, New York, United States of America
- Department of Physics, New York University, New York, New York, United States of America
- * E-mail:
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22
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Murillo-Maldonado JM, Zeineddine FB, Stock R, Thackeray J, Riesgo-Escovar JR. Insulin receptor-mediated signaling via phospholipase C-γ regulates growth and differentiation in Drosophila. PLoS One 2011; 6:e28067. [PMID: 22132213 PMCID: PMC3221684 DOI: 10.1371/journal.pone.0028067] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 10/31/2011] [Indexed: 02/06/2023] Open
Abstract
Coordination between growth and patterning/differentiation is critical if appropriate final organ structure and size is to be achieved. Understanding how these two processes are regulated is therefore a fundamental and as yet incompletely answered question. Here we show through genetic analysis that the phospholipase C-γ (PLC-γ) encoded by small wing (sl) acts as such a link between growth and patterning/differentiation by modulating some MAPK outputs once activated by the insulin pathway; particularly, sl promotes growth and suppresses ectopic differentiation in the developing eye and wing, allowing cells to attain a normal size and differentiate properly. sl mutants have previously been shown to have a combination of both growth and patterning/differentiation phenotypes: small wings, ectopic wing veins, and extra R7 photoreceptor cells. We show here that PLC-γ activated by the insulin pathway participates broadly and positively during cell growth modulating EGF pathway activity, whereas in cell differentiation PLC-γ activated by the insulin receptor negatively regulates the EGF pathway. These roles require different SH2 domains of PLC-γ, and act via classic PLC-γ signaling and EGF ligand processing. By means of PLC-γ, the insulin receptor therefore modulates differentiation as well as growth. Overall, our results provide evidence that PLC-γ acts during development at a time when growth ends and differentiation begins, and is important for proper coordination of these two processes.
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Affiliation(s)
- Juan M. Murillo-Maldonado
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México Campus Juriquilla, Querétaro, Querétaro, México
| | - Fouad Bou Zeineddine
- Biology Department, Clark University, Worcester, Maine, United States of America
| | - Rachel Stock
- Biology Department, Clark University, Worcester, Maine, United States of America
| | - Justin Thackeray
- Biology Department, Clark University, Worcester, Maine, United States of America
| | - Juan R. Riesgo-Escovar
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México Campus Juriquilla, Querétaro, Querétaro, México
- * E-mail:
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23
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Gambis A, Dourlen P, Steller H, Mollereau B. Two-color in vivo imaging of photoreceptor apoptosis and development in Drosophila. Dev Biol 2011; 351:128-34. [PMID: 21215264 DOI: 10.1016/j.ydbio.2010.12.040] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2010] [Revised: 12/22/2010] [Accepted: 12/22/2010] [Indexed: 11/25/2022]
Abstract
We report a new two-color fluorescent imaging system to visualize the mosaic adult photoreceptor neurons (PRs) in real-time. Using this method, we examined a collection of 434 mutants and identified genes required for PR survival, planar cell polarity (PCP), patterning and differentiation. We could track the progression of PR degeneration in living flies. By introducing the expression of p35, a caspase inhibitor, we found mutations that specifically activate caspase-dependent death. Moreover, we showed that grh is required in R3 for correct PCP establishment. The "Tomato/GFP-FLP/FRT" method allows high-throughput, rapid and precise identification of survival and developmental pathways in living adult PRs at single-cell resolution.
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Affiliation(s)
- Alexis Gambis
- Howard Hughes Medical Institute, Laboratory of Apoptosis and Cancer, The Rockefeller University, New York, NY 10065, USA
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24
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Brioudes F, Thierry AM, Chambrier P, Mollereau B, Bendahmane M. Translationally controlled tumor protein is a conserved mitotic growth integrator in animals and plants. Proc Natl Acad Sci U S A 2010; 107:16384-9. [PMID: 20736351 PMCID: PMC2941279 DOI: 10.1073/pnas.1007926107] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The growth of an organism and its size determination require the tight regulation of cell proliferation and cell growth. However, the mechanisms and regulatory networks that control and integrate these processes remain poorly understood. Here, we address the biological role of Arabidopsis translationally controlled tumor protein (AtTCTP) and test its shared functions in animals and plants. The data support a role of plant AtTCTP as a positive regulator of mitotic growth by specifically controlling the duration of the cell cycle. We show that, in contrast to animal TCTP, plant AtTCTP is not implicated in regulating postmitotic growth. Consistent with this finding, plant AtTCTP can fully rescue cell proliferation defects in Drosophila loss of function for dTCTP. Furthermore, Drosophila dTCTP is able to fully rescue cell proliferation defects in Arabidopsis tctp knockouts. Our data provide evidence that TCTP function in regulating cell division is part of a conserved growth regulatory pathway shared between plants and animals. The study also suggests that, although the cell division machinery is shared in all multicellular organisms to control growth, cell expansion can be uncoupled from cell division in plants but not in animals.
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Affiliation(s)
- Florian Brioudes
- Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Ecole Normale Supérieure, Université de Lyon, 69364 Lyon, France; and
| | - Anne-Marie Thierry
- Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Ecole Normale Supérieure, Université de Lyon, 69364 Lyon, France; and
| | - Pierre Chambrier
- Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Ecole Normale Supérieure, Université de Lyon, 69364 Lyon, France; and
| | - Bertrand Mollereau
- Laboratoire de Biologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, Ecole Normale Supérieure, Université de Lyon, 69364 Lyon, France
| | - Mohammed Bendahmane
- Reproduction et Développement des Plantes, Institut National de la Recherche Agronomique, Centre National de la Recherche Scientifique, Ecole Normale Supérieure, Université de Lyon, 69364 Lyon, France; and
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25
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Guenin L, Raharijaona M, Houlgatte R, Baba-Aissa F. Expression profiling of prospero in the Drosophila larval chemosensory organ: Between growth and outgrowth. BMC Genomics 2010; 11:47. [PMID: 20085633 PMCID: PMC2826315 DOI: 10.1186/1471-2164-11-47] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2009] [Accepted: 01/19/2010] [Indexed: 11/11/2022] Open
Abstract
Background The antenno-maxilary complex (AMC) forms the chemosensory system of the Drosophila larva and is involved in gustatory and olfactory perception. We have previously shown that a mutant allele of the homeodomain transcription factor Prospero (prosVoila1, V1), presents several developmental defects including abnormal growth and altered taste responses. In addition, many neural tracts connecting the AMC to the central nervous system (CNS) were affected. Our earlier reports on larval AMC did not argue in favour of a role of pros in cell fate decision, but strongly suggested that pros could be involved in the control of other aspect of neuronal development. In order to identify these functions, we used microarray analysis of larval AMC and CNS tissue isolated from the wild type, and three other previously characterised prospero alleles, including the V1 mutant, considered as a null allele for the AMC. Results A total of 17 samples were first analysed with hierarchical clustering. To determine those genes affected by loss of pros function, we calculated a discriminating score reflecting the differential expression between V1 mutant and other pros alleles. We identified a total of 64 genes in the AMC. Additional manual annotation using all the computed information on the attributed role of these genes in the Drosophila larvae nervous system, enabled us to identify one functional category of potential Prospero target genes known to be involved in neurite outgrowth, synaptic transmission and more specifically in neuronal connectivity remodelling. The second category of genes found to be differentially expressed between the null mutant AMC and the other alleles concerned the development of the sensory organs and more particularly the larval olfactory system. Surprisingly, a third category emerged from our analyses and suggests an association of pros with the genes that regulate autophagy, growth and insulin pathways. Interestingly, EGFR and Notch pathways were represented in all of these three functional categories. We now propose that Pros could perform all of these different functions through the modulation of these two antagonistic and synergic pathways. Conclusions The current data contribute to the clarification of the prospero function in the larval AMC and show that pros regulates different function in larvae as compared to those controlled by this gene in embryos. In the future, the possible mechanism by which Pros could achieve its function in the AMC will be explored in detail.
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Affiliation(s)
- Laure Guenin
- Université de Bourgogne, Facultés des Sciences, Unité Mixte de Recherche 5548 Associée au Centre National de la Recherche Scientifique, 6, Bd Gabriel, 21 000 Dijon, France
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26
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Abstract
"Tissue" or "planar" polarity is a characteristic of many epithelial tissues and is not only required for proper cell alignment, but in many instances is absolutely essential for normal function. Planar cell polarity (PCP) is the polarization of cells within the plane of an epithelium in a direction perpendicular to the axis of the apico-basal polarity. The oriented hair alignment in mammalian skin (feather in birds or scales in fish) and highly organized stereocilia bundles in the vertebrate inner ear are examples of such tissue organization. PCP was first described in Drosophila, with non-canonical Wnt signaling (also called PCP signaling, see Chapter 10, Volume 1) shown to be critical for its establishment. Two of the best characterized PCP models in Drosophila are the developing wing and the eye, where the graded activity of the Frizzled (Fz) receptor determines proximo-distal orientation of the wing hairs and mirror-imaged patterning of ommatidia, respectively. In this chapter, we describe simple methods to visualize PCP defects in the Drosophila eye and wing, in both developing and adult tissues. These methods include confocal immunofluorescent analysis of larval or pupal tissues, stained with antibodies specific to PCP components or cytoskeleton markers, and light microscopy of the adult eye and wing.
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27
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Identification of novel regulators of atonal expression in the developing Drosophila retina. Genetics 2008; 180:2095-110. [PMID: 18832354 DOI: 10.1534/genetics.108.093302] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Atonal is a Drosophila proneural protein required for the proper formation of the R8 photoreceptor cell, the founding photoreceptor cell in the developing retina. Proper expression and refinement of the Atonal protein is essential for the proper formation of the Drosophila adult eye. In vertebrates, expression of transcription factors orthologous to Drosophila Atonal (MATH5/Atoh7, XATH5, and ATH5) and their progressive restriction are also involved in specifying the retinal ganglion cell, the founding neural cell type in the mammalian retina. Thus, identifying factors that are involved in regulating the expression of Atonal during development are important to fully understand how retinal neurogenesis is accomplished. We have performed a chemical mutagenesis screen for autosomal dominant enhancers of a loss-of-function atonal eye phenotype. We report here the identification of five genes required for proper Atonal expression, three of which are novel regulators of Atonal expression in the Drosophila retina. We characterize the role of the daughterless, kismet, and roughened eye genes on atonal transcriptional regulation in the developing retina and show that each gene regulates atonal transcription differently within the context of retinal development. Our results provide additional insights into the regulation of Atonal expression in the developing Drosophila retina.
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Benchabane H, Hughes EG, Takacs CM, Baird JR, Ahmed Y. Adenomatous polyposis coli is present near the minimal level required for accurate graded responses to the Wingless morphogen. Development 2008; 135:963-71. [PMID: 18234723 DOI: 10.1242/dev.013805] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The mechanisms by which the Wingless (Wg) morphogen modulates the activity of the transcriptional activator Armadillo (Arm) to elicit precise, concentration-dependent cellular responses remain uncertain. Arm is targeted for proteolysis by the Axin/Adenomatous polyposis coli (Apc1 and Apc2)/Zeste-white 3 destruction complex, and Wg-dependent inactivation of destruction complex activity is crucial to trigger Arm signaling. In the prevailing model for Wg transduction, only Axin levels limit destruction complex activity, whereas Apc is present in vast excess. To test this model, we reduced Apc activity to different degrees, and analyzed the effects on three concentration-dependent responses to Arm signaling that specify distinct retinal photoreceptor fates. We find that both Apc1 and Apc2 negatively regulate Arm activity in photoreceptors, but that the relative contribution of Apc1 is much greater than that of Apc2. Unexpectedly, a less than twofold reduction in total Apc activity, achieved by loss of Apc2, decreases the effective threshold at which Wg elicits a cellular response, thereby resulting in ectopic responses that are spatially restricted to regions with low Wg concentration. We conclude that Apc activity is not present in vast excess, but instead is near the minimal level required for accurate graded responses to the Wg morphogen.
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Affiliation(s)
- Hassina Benchabane
- Department of Genetics and the Norris Cotton Cancer Center, Dartmouth Medical School, Hanover, NH 03755, USA
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29
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Kinel-Tahan Y, Weiss H, Dgany O, Levine A, Wides R. Drosophila odz gene is required for multiple cell types in the compound retina. Dev Dyn 2007; 236:2541-54. [PMID: 17685476 DOI: 10.1002/dvdy.21284] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The Drosophila melanogaster pair-rule gene odz (odd Oz, or Ten-m) is expressed in distinct patterns in the larval eye imaginal disc. Its earliest eye expression occurs in ommatidial precursors starting from the posterior edge of the morphogenetic furrow. Loss of function of odz activity leads to visible light photoreceptor loss; R7 photoreceptor loss; ommatidial size, shape, and rotation defects; ommatidial disorder and fusions; interommatidial bristle defects; and ommatidial lens defects. The same effects are seen in odz eye mitotic clones, in odz-Ten-a transheterozygous combinations, and in eyes expressing an Odz-Dominant Negative transgene (Odz-DN). Effects of the same strength are also seen when the Odz-DN transgene is driven only in regions of scabrous expression, which overlaps the four columns of Odz expression clusters behind the furrow. Small odz mitotic clones suggest an odz role in cell proliferation or survival. Senseless is expressed in odz mutant clones, in a fairly ordered manner, indicating that Odz acts downstream of R8 specification. Disorder within each ommatidium in odz clones is accompanied by some loss of R7 precursors and visible photoreceptor precursor order.
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Affiliation(s)
- Yael Kinel-Tahan
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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30
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Nilsson DE, Kelber A. A functional analysis of compound eye evolution. ARTHROPOD STRUCTURE & DEVELOPMENT 2007; 36:373-385. [PMID: 18089116 DOI: 10.1016/j.asd.2007.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Revised: 07/08/2007] [Accepted: 07/24/2007] [Indexed: 05/25/2023]
Abstract
New data on the phylogenetic relationships of various arthropod groups have spurred interesting attempts to reconstruct the evolution of arthropod nervous and visual systems. Some of the relevant new data are cell identities and developmental processes in the nervous and sensory systems, which is particularly useful for reconstructing the evolution of these systems. Here, we focus on the structure of compound eye ommatidia, and make an evolutionary analysis with functional arguments. We investigate possible routes of evolution that can be understood in terms of selection for improved visual function, and arrive at a number of conclusions that are discussed in the light of recent phylogenetic hypotheses. On the basis of ommatidial focusing structures and the arrangement of receptor cells we show that the evolution of compound eyes proceeded largely independently along at least two lineages from very primitive ancestors. A common ancestor of insects and crustaceans is likely to have had ommatidia with focusing crystalline cones, and colour and/or polarization vision. In contrast, the compound eyes in myriapods and chelicerates are likely to date back to ancestors with corneal lenses and probably without the ability to discriminate colour and polarization.
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Affiliation(s)
- Dan-E Nilsson
- Department of Cell and Organism Biology, Lund University, Zoology Building, Helgonavägen 3, 223 62 Lund, Sweden.
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31
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Xie B, Charlton-Perkins M, McDonald E, Gebelein B, Cook T. Senseless functions as a molecular switch for color photoreceptor differentiation in Drosophila. Development 2007; 134:4243-53. [PMID: 17978002 DOI: 10.1242/dev.012781] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A major question in development is how different specialized cell types arise from a common progenitor. In the adult Drosophila compound eye, color discrimination is achieved by UV-, blue- and green-sensitive photoreceptors (PRs). These different PR subsets arise from neuronal precursors called R7 and R8 cells. Recent studies have demonstrated that R7-based UV-sensitive PRs require the repression of R8-based blue/green-sensitive PR characteristics to properly develop. This repression is mediated by the transcription factor Prospero (Pros). Here, we report that Senseless (Sens), a Drosophila ortholog of the vertebrate Gfi1 transcription factor, plays an opposing role to Pros by both negatively regulating R7-based features and positively enforcing R8-based features during terminal differentiation. In addition, we demonstrate that Pros and Sens function together with the transcription factor Orthodenticle (Otd) to oppositely regulate R7 and R8 PR Rhodopsin gene expression in vitro. These data show that sens, previously shown to be essential for neuronal specification, also controls differentiation of specific neuronal subtypes in the retina. Interestingly, Pros has recently been shown to function as a tumor suppressor, whereas Gfi1 is a well-characterized oncogene. Thus, we propose that sens/pros antagonism is important for regulating many biological processes.
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Affiliation(s)
- Baotong Xie
- Department of Pediatric Ophthalmology, Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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32
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Abstract
Progress in the study of the molecular mechanisms that regulate neuronal differentiation has been quite impressive in recent years, and promises to continue to an equally fast pace. This should not lead us into a sense of complacency, however, because there are still significant barriers that cannot be overcome by simply conducting the same type of experiments that we have been performing thus far. This article will describe some of these challenges, while highlighting the conceptual and methodological breakthroughs that will be necessary to overcome them.
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Affiliation(s)
- Ruben Adler
- Department of Ophthalmology and Neuroscience The Johns Hopkins University School of Medicine Baltimore, MD 21287-9257, USA.
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