1
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Zhang J, Jiang Z, Shi A. Rab GTPases: The principal players in crafting the regulatory landscape of endosomal trafficking. Comput Struct Biotechnol J 2022; 20:4464-4472. [PMID: 36051867 PMCID: PMC9418685 DOI: 10.1016/j.csbj.2022.08.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 08/05/2022] [Accepted: 08/07/2022] [Indexed: 11/16/2022] Open
Abstract
After endocytosis, diverse cargos are sorted into endosomes and directed to various destinations, including extracellular macromolecules, membrane lipids, and membrane proteins. Some cargos are returned to the plasma membrane via endocytic recycling. In contrast, others are delivered to the Golgi apparatus through the retrograde pathway, while the rest are transported to late endosomes and eventually to lysosomes for degradation. Rab GTPases are major regulators that ensure cargos are delivered to their proper destinations. Rabs are localized to distinct endosomes and play predominant roles in membrane budding, vesicle formation and motility, vesicle tethering, and vesicle fusion by recruiting effectors. The cascades between Rabs via shared effectors or the recruitment of Rab activators provide an additional layer of spatiotemporal regulation of endocytic trafficking. Notably, several recent studies have indicated that disorders of Rab-mediated endocytic transports are closely associated with diseases such as immunodeficiency, cancer, and neurological disorders.
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2
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Li-Leger E, Feichtinger R, Flibotte S, Holzkamp H, Schnabel R, Moerman DG. Identification of essential genes in Caenorhabditis elegans through whole genome sequencing of legacy mutant collections. G3-GENES GENOMES GENETICS 2021; 11:6373896. [PMID: 34550348 PMCID: PMC8664450 DOI: 10.1093/g3journal/jkab328] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 08/27/2021] [Indexed: 01/23/2023]
Abstract
It has been estimated that 15%–30% of the ∼20,000 genes in C. elegans are essential, yet many of these genes remain to be identified or characterized. With the goal of identifying unknown essential genes, we performed whole-genome sequencing on complementation pairs from legacy collections of maternal-effect lethal and sterile mutants. This approach uncovered maternal genes required for embryonic development and genes with apparent sperm-specific functions. In total, 58 putative essential genes were identified on chromosomes III–V, of which 52 genes are represented by novel alleles in this collection. Of these 52 genes, 19 (40 alleles) were selected for further functional characterization. The terminal phenotypes of embryos were examined, revealing defects in cell division, morphogenesis, and osmotic integrity of the eggshell. Mating assays with wild-type males revealed previously unknown male-expressed genes required for fertilization and embryonic development. The result of this study is a catalog of mutant alleles in essential genes that will serve as a resource to guide further study toward a more complete understanding of this important model organism. As many genes and developmental pathways in C. elegans are conserved and essential genes are often linked to human disease, uncovering the function of these genes may also provide insight to further our understanding of human biology.
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Affiliation(s)
- Erica Li-Leger
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Richard Feichtinger
- Department of Developmental Genetics, Institute of Genetics, Technische Universität Braunschweig, 38106, Germany
| | - Stephane Flibotte
- UBC/LSI Bioinformatics Facility, University of British Columbia, Vancouver, British Columbia, Canada
| | - Heinke Holzkamp
- Department of Developmental Genetics, Institute of Genetics, Technische Universität Braunschweig, 38106, Germany
| | - Ralf Schnabel
- Department of Developmental Genetics, Institute of Genetics, Technische Universität Braunschweig, 38106, Germany
| | - Donald G Moerman
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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3
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Nguyen JA, Yates RM. Better Together: Current Insights Into Phagosome-Lysosome Fusion. Front Immunol 2021; 12:636078. [PMID: 33717183 PMCID: PMC7946854 DOI: 10.3389/fimmu.2021.636078] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/18/2021] [Indexed: 12/15/2022] Open
Abstract
Following phagocytosis, the nascent phagosome undergoes maturation to become a phagolysosome with an acidic, hydrolytic, and often oxidative lumen that can efficiently kill and digest engulfed microbes, cells, and debris. The fusion of phagosomes with lysosomes is a principal driver of phagosomal maturation and is targeted by several adapted intracellular pathogens. Impairment of this process has significant consequences for microbial infection, tissue inflammation, the onset of adaptive immunity, and disease. Given the importance of phagosome-lysosome fusion to phagocyte function and the many virulence factors that target it, it is unsurprising that multiple molecular pathways have evolved to mediate this essential process. While the full range of these pathways has yet to be fully characterized, several pathways involving proteins such as members of the Rab GTPases, tethering factors and SNAREs have been identified. Here, we summarize the current state of knowledge to clarify the ambiguities in the field and construct a more comprehensive phagolysosome formation model. Lastly, we discuss how other cellular pathways help support phagolysosome biogenesis and, consequently, phagocyte function.
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Affiliation(s)
- Jenny A Nguyen
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Robin M Yates
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.,Cumming School of Medicine, Snyder Institute of Chronic Disease, University of Calgary, Calgary, AB, Canada
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4
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Voss L, Foster OK, Harper L, Morris C, Lavoy S, Brandt JN, Peloza K, Handa S, Maxfield A, Harp M, King B, Eichten V, Rambo FM, Hermann GJ. An ABCG Transporter Functions in Rab Localization and Lysosome-Related Organelle Biogenesis in Caenorhabditis elegans. Genetics 2020; 214:419-445. [PMID: 31848222 PMCID: PMC7017009 DOI: 10.1534/genetics.119.302900] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 12/11/2019] [Indexed: 12/20/2022] Open
Abstract
ABC transporters couple ATP hydrolysis to the transport of substrates across cellular membranes. This protein superfamily has diverse activities resulting from differences in their cargo and subcellular localization. Our work investigates the role of the ABCG family member WHT-2 in the biogenesis of gut granules, a Caenorhabditis elegans lysosome-related organelle. In addition to being required for the accumulation of birefringent material within gut granules, WHT-2 is necessary for the localization of gut granule proteins when trafficking pathways to this organelle are partially disrupted. The role of WHT-2 in gut granule protein targeting is likely linked to its function in Rab GTPase localization. We show that WHT-2 promotes the gut granule association of the Rab32 family member GLO-1 and the endolysosomal RAB-7, identifying a novel function for an ABC transporter. WHT-2 localizes to gut granules where it could play a direct role in controlling Rab localization. Loss of CCZ-1 and GLO-3, which likely function as a guanine nucleotide exchange factor (GEF) for GLO-1, lead to similar disruption of GLO-1 localization. We show that CCZ-1, like GLO-3, is localized to gut granules. WHT-2 does not direct the gut granule association of the GLO-1 GEF and our results point to WHT-2 functioning differently than GLO-3 and CCZ-1 Point mutations in WHT-2 that inhibit its transport activity, but not its subcellular localization, lead to the loss of GLO-1 from gut granules, while other WHT-2 activities are not completely disrupted, suggesting that WHT-2 functions in organelle biogenesis through transport-dependent and transport-independent activities.
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Affiliation(s)
- Laura Voss
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Olivia K Foster
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Logan Harper
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Caitlin Morris
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Sierra Lavoy
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - James N Brandt
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Kimberly Peloza
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Simran Handa
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Amanda Maxfield
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Marie Harp
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Brian King
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | | | - Fiona M Rambo
- Department of Biology, Lewis & Clark College, Portland, Oregon
| | - Greg J Hermann
- Department of Biology, Lewis & Clark College, Portland, Oregon
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5
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Reduction of mRNA export unmasks different tissue sensitivities to low mRNA levels during Caenorhabditis elegans development. PLoS Genet 2019; 15:e1008338. [PMID: 31525188 PMCID: PMC6762213 DOI: 10.1371/journal.pgen.1008338] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 09/26/2019] [Accepted: 07/31/2019] [Indexed: 12/25/2022] Open
Abstract
Animal development requires the execution of specific transcriptional programs in different sets of cells to build tissues and functional organs. Transcripts are exported from the nucleus to the cytoplasm where they are translated into proteins that, ultimately, carry out the cellular functions. Here we show that in Caenorhabditis elegans, reduction of mRNA export strongly affects epithelial morphogenesis and germline proliferation while other tissues remain relatively unaffected. Epithelialization and gamete formation demand a large number of transcripts in the cytoplasm for the duration of these processes. In addition, our findings highlight the existence of a regulatory feedback mechanism that activates gene expression in response to low levels of cytoplasmic mRNA. We expand the genetic characterization of nuclear export factor NXF-1 to other members of the mRNA export pathway to model mRNA export and recycling of NXF-1 back to the nucleus. Our model explains how mutations in genes involved in general processes, such as mRNA export, may result in tissue-specific developmental phenotypes. The Central Dogma of Biology schematically highlights the transmission of genetic information stored in DNA, through RNA, to the formation of proteins. This general flow implicates RNA export from the nucleus to the cytoplasm and proper protein localization within the eukaryotic cell. Ultimately, proteins are the cell’s structural and catalytic functional units. As a result, cells differentiate into one cell type or another (such as epithelial, muscle, neuron…) and exhibit specific shape and functionality. Here we describe, in a C. elegans model, how mutations in genes involved in a general and ubiquitous mechanism, such as mRNA export, may result in tissue-specific developmental phenotypes that show up in processes that are highly demanding of cytoplasmic transcripts like epithelialization and gamete formation. A deep understanding of the mechanisms underlying the "connectors" shown in the Central Dogma of Biology is key both to unravel the general genetic control of an organism’s development and, at the same time, contribute to a better understanding of tissue-specific diseases.
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6
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Gómez-Orte E, Sáenz-Narciso B, Zheleva A, Ezcurra B, de Toro M, López R, Gastaca I, Nilsen H, Sacristán MP, Schnabel R, Cabello J. Disruption of the Caenorhabditis elegans Integrator complex triggers a non-conventional transcriptional mechanism beyond snRNA genes. PLoS Genet 2019; 15:e1007981. [PMID: 30807579 PMCID: PMC6390993 DOI: 10.1371/journal.pgen.1007981] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 01/22/2019] [Indexed: 01/09/2023] Open
Abstract
Gene expression is generally regulated by recruitment of transcription factors and RNA polymerase II (RNAP II) to specific sequences in the gene promoter region. The Integrator complex mediates processing of small nuclear RNAs (snRNAs) as well as the initiation and release of paused RNAP II at specific genes in response to growth factors. Here we show that in C. elegans, disruption of the Integrator complex leads to transcription of genes located downstream of the snRNA loci via a non-conventional transcription mechanism based on the lack of processing of the snRNAs. RNAP II read-through generates long chimeric RNAs containing snRNA, the intergenic region and the mature mRNA of the downstream gene located in sense. These chimeric sn-mRNAs remain as untranslated long non-coding RNAs, in the case of U1- and U2-derived sn-mRNAs, but can be translated to proteins in the case of SL-derived sn-mRNAs. The transcriptional effect caused by disruption of the Integrator complex is not restricted to genes located downstream of the snRNA loci but also affects key regulators of signal transduction such as kinases and phosphatases. Our findings highlight that these transcriptional alterations may be behind the correlation between mutations in the Integrator complex and tumor transformation.
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Affiliation(s)
- Eva Gómez-Orte
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - Beatriz Sáenz-Narciso
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - Angelina Zheleva
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - Begoña Ezcurra
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - María de Toro
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - Rosario López
- Scientific Computing Group (GRUCACI), University of La Rioja, Logroño, La Rioja, Spain
| | - Irene Gastaca
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, Institute of Clinical Medicine, University of Oslo and Akershus University Hospital, Lørenskog, Norway
| | - María P. Sacristán
- Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, CSIC-Universidad de Salamanca, Salamanca, Spain
| | - Ralf Schnabel
- Department of Developmental Genetics, Institute of Genetics, Technische Universität Braunschweig, Braunschweig, Germany
| | - Juan Cabello
- Oncology Area, CIBIR (Center for Biomedical Research of La Rioja), Logroño, La Rioja, Spain
- * E-mail:
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7
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Guerrero-Gómez D, Mora-Lorca JA, Sáenz-Narciso B, Naranjo-Galindo FJ, Muñoz-Lobato F, Parrado-Fernández C, Goikolea J, Cedazo-Minguez Á, Link CD, Neri C, Sequedo MD, Vázquez-Manrique RP, Fernández-Suárez E, Goder V, Pané R, Cabiscol E, Askjaer P, Cabello J, Miranda-Vizuete A. Loss of glutathione redox homeostasis impairs proteostasis by inhibiting autophagy-dependent protein degradation. Cell Death Differ 2019; 26:1545-1565. [PMID: 30770874 DOI: 10.1038/s41418-018-0270-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 12/04/2018] [Accepted: 12/20/2018] [Indexed: 01/10/2023] Open
Abstract
In the presence of aggregation-prone proteins, the cytosol and endoplasmic reticulum (ER) undergo a dramatic shift in their respective redox status, with the cytosol becoming more oxidized and the ER more reducing. However, whether and how changes in the cellular redox status may affect protein aggregation is unknown. Here, we show that C. elegans loss-of-function mutants for the glutathione reductase gsr-1 gene enhance the deleterious phenotypes of heterologous human, as well as endogenous worm aggregation-prone proteins. These effects are phenocopied by the GSH-depleting agent diethyl maleate. Additionally, gsr-1 mutants abolish the nuclear translocation of HLH-30/TFEB transcription factor, a key inducer of autophagy, and strongly impair the degradation of the autophagy substrate p62/SQST-1::GFP, revealing glutathione reductase may have a role in the clearance of protein aggregates by autophagy. Blocking autophagy in gsr-1 worms expressing aggregation-prone proteins results in strong synthetic developmental phenotypes and lethality, supporting the physiological importance of glutathione reductase in the regulation of misfolded protein clearance. Furthermore, impairing redox homeostasis in both yeast and mammalian cells induces toxicity phenotypes associated with protein aggregation. Together, our data reveal that glutathione redox homeostasis may be central to proteostasis maintenance through autophagy regulation.
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Affiliation(s)
- David Guerrero-Gómez
- Redox Homeostasis Group, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Sevilla, Spain
| | - José Antonio Mora-Lorca
- Redox Homeostasis Group, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Sevilla, Spain.,Departamento de Farmacología, Facultad de Farmacia, Universidad de Sevilla, 41012, Sevilla, Spain
| | | | - Francisco José Naranjo-Galindo
- Redox Homeostasis Group, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Sevilla, Spain
| | - Fernando Muñoz-Lobato
- Redox Homeostasis Group, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Sevilla, Spain
| | - Cristina Parrado-Fernández
- Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Stockholm, SE-14186, Sweden
| | - Julen Goikolea
- Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Stockholm, SE-14186, Sweden
| | - Ángel Cedazo-Minguez
- Karolinska Institutet, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Division of Neurogeriatrics, Stockholm, SE-14186, Sweden
| | - Christopher D Link
- Department of Integrative Physiology, Institute for Behavioral Genetics, University of Colorado at Boulder, Boulder, CO, 80309, USA
| | - Christian Neri
- Sorbonnes Université, Centre National de la Recherche Scientifique, Research Unit Biology of Adaptation and Aging (B2A), Team Compensation in Neurodegenerative and Aging (Brain-C), F-75252, Paris, France
| | - María Dolores Sequedo
- Research Group in Molecular, Cellular and Genomic Biomedicine, Health Research Institute-La Fe, 46026, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Rafael P Vázquez-Manrique
- Research Group in Molecular, Cellular and Genomic Biomedicine, Health Research Institute-La Fe, 46026, Valencia, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Elena Fernández-Suárez
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Sevilla, Spain
| | - Veit Goder
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Sevilla, Spain
| | - Roser Pané
- Departament de Ciències Mèdiques Bàsiques, IRB Lleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Elisa Cabiscol
- Departament de Ciències Mèdiques Bàsiques, IRB Lleida, Universitat de Lleida, Av. Rovira Roure, 80, 25198, Lleida, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013, Seville, Spain
| | - Juan Cabello
- CIBIR (Center for Biomedical Research of La Rioja), 26006, Logroño, Spain.
| | - Antonio Miranda-Vizuete
- Redox Homeostasis Group, Instituto de Biomedicina de Sevilla (IBIS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013, Sevilla, Spain.
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8
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Morris C, Foster OK, Handa S, Peloza K, Voss L, Somhegyi H, Jian Y, Vo MV, Harp M, Rambo FM, Yang C, Hermann GJ. Function and regulation of the Caenorhabditis elegans Rab32 family member GLO-1 in lysosome-related organelle biogenesis. PLoS Genet 2018; 14:e1007772. [PMID: 30419011 PMCID: PMC6268011 DOI: 10.1371/journal.pgen.1007772] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 11/30/2018] [Accepted: 10/17/2018] [Indexed: 02/07/2023] Open
Abstract
Cell type-specific modifications of conventional endosomal trafficking pathways lead to the formation of lysosome-related organelles (LROs). C. elegans gut granules are intestinally restricted LROs that coexist with conventional degradative lysosomes. The formation of gut granules requires the Rab32 family member GLO-1. We show that the loss of glo-1 leads to the mistrafficking of gut granule proteins but does not significantly alter conventional endolysosome biogenesis. GLO-3 directly binds to CCZ-1 and they both function to promote the gut granule association of GLO-1, strongly suggesting that together, GLO-3 and CCZ-1 activate GLO-1. We found that a point mutation in GLO-1 predicted to spontaneously activate, and function independently of it guanine nucleotide exchange factor (GEF), localizes to gut granules and partially restores gut granule protein localization in ccz-1(-) and glo-3(-) mutants. CCZ-1 forms a heterodimeric complex with SAND-1(MON1), which does not function in gut granule formation, to activate RAB-7 in trafficking pathways to conventional lysosomes. Therefore, our data suggest a model whereby the function of a Rab GEF can be altered by subunit exchange. glo-3(-) mutants, which retain low levels of GLO-3 activity, generate gut granules that lack GLO-1 and improperly accumulate RAB-7 in a SAND-1 dependent process. We show that GLO-1 and GLO-3 restrict the distribution of RAB-7 to conventional endolysosomes, providing insights into the segregation of pathways leading to conventional lysosomes and LROs.
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Affiliation(s)
- Caitlin Morris
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Olivia K. Foster
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Simran Handa
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Kimberly Peloza
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Laura Voss
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Hannah Somhegyi
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Youli Jian
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - My Van Vo
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Marie Harp
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Fiona M. Rambo
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
| | - Chonglin Yang
- State Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Greg J. Hermann
- Department of Biology, Lewis & Clark College, Portland, Oregon, United States of America
- * E-mail:
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9
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Programmed Cell Death During Caenorhabditis elegans Development. Genetics 2017; 203:1533-62. [PMID: 27516615 DOI: 10.1534/genetics.115.186247] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/22/2016] [Indexed: 12/21/2022] Open
Abstract
Programmed cell death is an integral component of Caenorhabditis elegans development. Genetic and reverse genetic studies in C. elegans have led to the identification of many genes and conserved cell death pathways that are important for the specification of which cells should live or die, the activation of the suicide program, and the dismantling and removal of dying cells. Molecular, cell biological, and biochemical studies have revealed the underlying mechanisms that control these three phases of programmed cell death. In particular, the interplay of transcriptional regulatory cascades and networks involving multiple transcriptional regulators is crucial in activating the expression of the key death-inducing gene egl-1 and, in some cases, the ced-3 gene in cells destined to die. A protein interaction cascade involving EGL-1, CED-9, CED-4, and CED-3 results in the activation of the key cell death protease CED-3, which is tightly controlled by multiple positive and negative regulators. The activation of the CED-3 caspase then initiates the cell disassembly process by cleaving and activating or inactivating crucial CED-3 substrates; leading to activation of multiple cell death execution events, including nuclear DNA fragmentation, mitochondrial elimination, phosphatidylserine externalization, inactivation of survival signals, and clearance of apoptotic cells. Further studies of programmed cell death in C. elegans will continue to advance our understanding of how programmed cell death is regulated, activated, and executed in general.
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10
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Sáenz‐Narciso B, Gómez‐Orte E, Zheleva A, Gastaca I, Cabello J. Control of developmental networks by Rac/Rho small GTPases: How cytoskeletal changes during embryogenesis are orchestrated. Bioessays 2016; 38:1246-1254. [PMID: 27790724 PMCID: PMC5132145 DOI: 10.1002/bies.201600165] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Small GTPases in the Rho family act as major nodes with functions beyond cytoskeletal rearrangements shaping the Caenorhabditis elegans embryo during development. These small GTPases are key signal transducers that integrate diverse developmental signals to produce a coordinated response in the cell. In C. elegans, the best studied members of these highly conserved Rho family small GTPases, RHO-1/RhoA, CED-10/Rac, and CDC-42, are crucial in several cellular processes dealing with cytoskeletal reorganization. In this review, we update the functions described for the Rho family small GTPases in spindle orientation and cell division, engulfment, and cellular movements during C. elegans embryogenesis, focusing on the Rho subfamily Rac. Please also see the video abstract here.
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Affiliation(s)
| | - Eva Gómez‐Orte
- Center for Biomedical Research of La Rioja (CIBIR)LogroñoSpain
| | | | - Irene Gastaca
- Center for Biomedical Research of La Rioja (CIBIR)LogroñoSpain
| | - Juan Cabello
- Center for Biomedical Research of La Rioja (CIBIR)LogroñoSpain
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11
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Liu K, Jian Y, Sun X, Yang C, Gao Z, Zhang Z, Liu X, Li Y, Xu J, Jing Y, Mitani S, He S, Yang C. Negative regulation of phosphatidylinositol 3-phosphate levels in early-to-late endosome conversion. J Cell Biol 2016; 212:181-98. [PMID: 26783301 PMCID: PMC4738380 DOI: 10.1083/jcb.201506081] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
C. elegans SORF-1 and SORF-2 and their mammalian homologs WDR91 and WDR81 maintain appropriate PtdIns3P levels in early-to-late endosome conversion by forming a complex with the Beclin1 subunit of the PI3K complex. Phosphatidylinositol 3-phosphate (PtdIns3P) plays a central role in endosome fusion, recycling, sorting, and early-to-late endosome conversion, but the mechanisms that determine how the correct endosomal PtdIns3P level is achieved remain largely elusive. Here we identify two new factors, SORF-1 and SORF-2, as essential PtdIns3P regulators in Caenorhabditis elegans. Loss of sorf-1 or sorf-2 leads to greatly elevated endosomal PtdIns3P, which drives excessive fusion of early endosomes. sorf-1 and sorf-2 function coordinately with Rab switching genes to inhibit synthesis of PtdIns3P, allowing its turnover for endosome conversion. SORF-1 and SORF-2 act in a complex with BEC-1/Beclin1, and their loss causes elevated activity of the phosphatidylinositol 3-kinase (PI3K) complex. In mammalian cells, inactivation of WDR91 and WDR81, the homologs of SORF-1 and SORF-2, induces Beclin1-dependent enlargement of PtdIns3P-enriched endosomes and defective degradation of epidermal growth factor receptor. WDR91 and WDR81 interact with Beclin1 and inhibit PI3K complex activity. These findings reveal a conserved mechanism that controls appropriate PtdIns3P levels in early-to-late endosome conversion.
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Affiliation(s)
- Kai Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China Graduate University of Chinese Academy of Sciences, Beijing 100109, China
| | - Youli Jian
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Xiaojuan Sun
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Chengkui Yang
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital and Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215123, China
| | - Zhiyang Gao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Zhili Zhang
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital and Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215123, China
| | - Xuezhao Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China Graduate University of Chinese Academy of Sciences, Beijing 100109, China
| | - Yang Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Jing Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Yudong Jing
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
| | - Shohei Mitani
- Department of Physiology, School of Medicine and Institute for Integrated Medical Sciences, Tokyo Women's Medical University, Shinjuku-ku, Tokyo 162-0054, Japan
| | - Sudan He
- Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, First Affiliated Hospital and Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215123, China
| | - Chonglin Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences. Beijing 100101, China
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12
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Mora-Lorca JA, Sáenz-Narciso B, Gaffney CJ, Naranjo-Galindo FJ, Pedrajas JR, Guerrero-Gómez D, Dobrzynska A, Askjaer P, Szewczyk NJ, Cabello J, Miranda-Vizuete A. Glutathione reductase gsr-1 is an essential gene required for Caenorhabditis elegans early embryonic development. Free Radic Biol Med 2016; 96:446-61. [PMID: 27117030 PMCID: PMC8386055 DOI: 10.1016/j.freeradbiomed.2016.04.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 04/18/2016] [Indexed: 12/22/2022]
Abstract
Glutathione is the most abundant thiol in the vast majority of organisms and is maintained in its reduced form by the flavoenzyme glutathione reductase. In this work, we describe the genetic and functional analysis of the Caenorhabditis elegans gsr-1 gene that encodes the only glutathione reductase protein in this model organism. By using green fluorescent protein reporters we demonstrate that gsr-1 produces two GSR-1 isoforms, one located in the cytoplasm and one in the mitochondria. gsr-1 loss of function mutants display a fully penetrant embryonic lethal phenotype characterized by a progressive and robust cell division delay accompanied by an aberrant distribution of interphasic chromatin in the periphery of the cell nucleus. Maternally expressed GSR-1 is sufficient to support embryonic development but these animals are short-lived, sensitized to chemical stress, have increased mitochondrial fragmentation and lower mitochondrial DNA content. Furthermore, the embryonic lethality of gsr-1 worms is prevented by restoring GSR-1 activity in the cytoplasm but not in mitochondria. Given the fact that the thioredoxin redox systems are dispensable in C. elegans, our data support a prominent role of the glutathione reductase/glutathione pathway in maintaining redox homeostasis in the nematode.
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Affiliation(s)
- José Antonio Mora-Lorca
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain; Departamento de Farmacología, Facultad de Farmacia, Universidad de Sevilla, 41012 Sevilla, Spain
| | | | - Christopher J Gaffney
- MRC/ARUK Centre for Musculoskeletal Ageing Research, University of Nottingham and Medical School Royal Derby Hospital, DE22 3DT Derby, United Kingdom
| | - Francisco José Naranjo-Galindo
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - José Rafael Pedrajas
- Grupo de Bioquímica y Señalización Celular, Departamento de Biología Experimental, Universidad de Jaén, 23071 Jaén, Spain
| | - David Guerrero-Gómez
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain
| | - Agnieszka Dobrzynska
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), CSIC/JA/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Nathaniel J Szewczyk
- MRC/ARUK Centre for Musculoskeletal Ageing Research, University of Nottingham and Medical School Royal Derby Hospital, DE22 3DT Derby, United Kingdom
| | - Juan Cabello
- Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain.
| | - Antonio Miranda-Vizuete
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain.
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13
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Boroda AV, Kipryushina YO, Yakovlev KV, Odintsova NA. The contribution of apoptosis and necrosis in freezing injury of sea urchin embryonic cells. Cryobiology 2016; 73:7-14. [PMID: 27364314 DOI: 10.1016/j.cryobiol.2016.06.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/20/2016] [Accepted: 06/25/2016] [Indexed: 11/26/2022]
Abstract
Sea urchins have recently been reported to be a promising tool for investigations of oxidative stress, UV light perturbations and senescence. However, few available data describe the pathway of cell death that occurs in sea urchin embryonic cells after cryopreservation. Our study is focused on the morphological and functional alterations that occur in cells of these animals during the induction of different cell death pathways in response to cold injury. To estimate the effect of cryopreservation on sea urchin cell cultures and identify the involved cell death pathways, we analyzed cell viability (via trypan blue exclusion test, MTT assay and DAPI staining), caspase activity (via flow cytometry and spectrophotometry), the level of apoptosis (via annexin V-FITC staining), and cell ultrastructure alterations (via transmission electron microscopy). Using general caspase detection, we found that the level of caspase activity was low in unfrozen control cells, whereas the number of apoptotic cells with activated caspases rose after freezing-thawing depending on cryoprotectants used, also as the number of dead cells and cells in a late apoptosis. The data using annexin V-binding assay revealed a very high apoptosis level in all tested samples, even in unfrozen cells (about 66%). Thus, annexin V assay appears to be unsuitable for sea urchin embryonic cells. Typical necrotic cells with damaged mitochondria were not detected after freezing in sea urchin cell cultures. Our results assume that physical cell disruption but not freezing-induced apoptosis or necrosis is the predominant reason of cell death in sea urchin cultures after freezing-thawing with any cryoprotectant combination.
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Affiliation(s)
- Andrey V Boroda
- Laboratory of Cytotechnology, A.V. Zhirmunsky Institute of Marine Biology, The Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690041, Russia
| | - Yulia O Kipryushina
- Laboratory of Cytotechnology, A.V. Zhirmunsky Institute of Marine Biology, The Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690041, Russia
| | - Konstantin V Yakovlev
- Laboratory of Cytotechnology, A.V. Zhirmunsky Institute of Marine Biology, The Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690041, Russia
| | - Nelly A Odintsova
- Laboratory of Cytotechnology, A.V. Zhirmunsky Institute of Marine Biology, The Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, 690041, Russia.
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14
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Wang X, Yang C. Programmed cell death and clearance of cell corpses in Caenorhabditis elegans. Cell Mol Life Sci 2016; 73:2221-36. [PMID: 27048817 PMCID: PMC11108496 DOI: 10.1007/s00018-016-2196-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 03/18/2016] [Indexed: 01/01/2023]
Abstract
Programmed cell death is critical to the development of diverse animal species from C. elegans to humans. In C. elegans, the cell death program has three genetically distinguishable phases. During the cell suicide phase, the core cell death machinery is activated through a protein interaction cascade. This activates the caspase CED-3, which promotes numerous pro-apoptotic activities including DNA degradation and exposure of the phosphatidylserine "eat me" signal on the cell corpse surface. Specification of the cell death fate involves transcriptional activation of the cell death initiator EGL-1 or the caspase CED-3 by coordinated actions of specific transcription factors in distinct cell types. In the cell corpse clearance stage, recognition of cell corpses by phagocytes triggers several signaling pathways to induce phagocytosis of apoptotic cell corpses. Cell corpse-enclosing phagosomes ultimately fuse with lysosomes for digestion of phagosomal contents. This article summarizes our current knowledge about programmed cell death and clearance of cell corpses in C. elegans.
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Affiliation(s)
- Xiaochen Wang
- National Institute of Biological Sciences, No. 7 Science Park Road, Zhongguancun Life Science Park, Beijing, 102206, China.
| | - Chonglin Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.
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15
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Ertl I, Porta-de-la-Riva M, Gómez-Orte E, Rubio-Peña K, Aristizábal-Corrales D, Cornes E, Fontrodona L, Osteikoetxea X, Ayuso C, Askjaer P, Cabello J, Cerón J. Functional Interplay of Two Paralogs Encoding SWI/SNF Chromatin-Remodeling Accessory Subunits During Caenorhabditis elegans Development. Genetics 2016; 202:961-75. [PMID: 26739451 PMCID: PMC4788132 DOI: 10.1534/genetics.115.183533] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/21/2015] [Indexed: 12/16/2022] Open
Abstract
SWI/SNF ATP-dependent chromatin-remodeling complexes have been related to several cellular processes such as transcription, regulation of chromosomal stability, and DNA repair. The Caenorhabditis elegans gene ham-3 (also known as swsn-2.1) and its paralog swsn-2.2 encode accessory subunits of SWI/SNF complexes. Using RNA interference (RNAi) assays and diverse alleles we investigated whether ham-3 and swsn-2.2 have different functions during C. elegans development since they encode proteins that are probably mutually exclusive in a given SWI/SNF complex. We found that ham-3 and swsn-2.2 display similar functions in vulva specification, germline development, and intestinal cell proliferation, but have distinct roles in embryonic development. Accordingly, we detected functional redundancy in some developmental processes and demonstrated by RNA sequencing of RNAi-treated L4 animals that ham-3 and swsn-2.2 regulate the expression of a common subset of genes but also have specific targets. Cell lineage analyses in the embryo revealed hyper-proliferation of intestinal cells in ham-3 null mutants whereas swsn-2.2 is required for proper cell divisions. Using a proteomic approach, we identified SWSN-2.2-interacting proteins needed for early cell divisions, such as SAO-1 and ATX-2, and also nuclear envelope proteins such as MEL-28. swsn-2.2 mutants phenocopy mel-28 loss-of-function, and we observed that SWSN-2.2 and MEL-28 colocalize in mitotic and meiotic chromosomes. Moreover, we demonstrated that SWSN-2.2 is required for correct chromosome segregation and nuclear reassembly after mitosis including recruitment of MEL-28 to the nuclear periphery.
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Affiliation(s)
- Iris Ertl
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Montserrat Porta-de-la-Riva
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain C. elegans Core Facility, Bellvitge Biomedical Research Institute-IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Eva Gómez-Orte
- Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain
| | - Karinna Rubio-Peña
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - David Aristizábal-Corrales
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Eric Cornes
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Laura Fontrodona
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Xabier Osteikoetxea
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
| | - Cristina Ayuso
- Andalusian Center for Developmental Biology (CABD), Consejo Superior de Investigaciones Científicas/Junta de Andalucia/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Peter Askjaer
- Andalusian Center for Developmental Biology (CABD), Consejo Superior de Investigaciones Científicas/Junta de Andalucia/Universidad Pablo de Olavide, 41013 Seville, Spain
| | - Juan Cabello
- Center for Biomedical Research of La Rioja (CIBIR), 26006 Logroño, Spain
| | - Julián Cerón
- Cancer and Human Molecular Genetics, Bellvitge Biomedical Research Institute-IDIBELL, 08908 L'Hospitalet de Llobregat, Barcelona, Spain
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16
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Genetics of Lipid-Storage Management in Caenorhabditis elegans Embryos. Genetics 2016; 202:1071-83. [PMID: 26773047 DOI: 10.1534/genetics.115.179127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 01/04/2016] [Indexed: 11/18/2022] Open
Abstract
Lipids play a pivotal role in embryogenesis as structural components of cellular membranes, as a source of energy, and as signaling molecules. On the basis of a collection of temperature-sensitive embryonic lethal mutants, a systematic database search, and a subsequent microscopic analysis of >300 interference RNA (RNAi)-treated/mutant worms, we identified a couple of evolutionary conserved genes associated with lipid storage in Caenorhabditis elegans embryos. The genes include cpl-1 (cathepsin L-like cysteine protease), ccz-1 (guanine nucleotide exchange factor subunit), and asm-3 (acid sphingomyelinase), which is closely related to the human Niemann-Pick disease-causing gene SMPD1. The respective mutant embryos accumulate enlarged droplets of neutral lipids (cpl-1) and yolk-containing lipid droplets (ccz-1) or have larger genuine lipid droplets (asm-3). The asm-3 mutant embryos additionally showed an enhanced resistance against C band ultraviolet (UV-C) light. Herein we propose that cpl-1, ccz-1, and asm-3 are genes required for the processing of lipid-containing droplets in C. elegans embryos. Owing to the high levels of conservation, the identified genes are also useful in studies of embryonic lipid storage in other organisms.
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17
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Abstract
Cell death is a common and important feature of animal development, and cell death defects underlie many human disease states. The nematode Caenorhabditis elegans has proven fertile ground for uncovering molecular and cellular processes controlling programmed cell death. A core pathway consisting of the conserved proteins EGL-1/BH3-only, CED-9/BCL2, CED-4/APAF1, and CED-3/caspase promotes most cell death in the nematode, and a conserved set of proteins ensures the engulfment and degradation of dying cells. Multiple regulatory pathways control cell death onset in C. elegans, and many reveal similarities with tumor formation pathways in mammals, supporting the idea that cell death plays key roles in malignant progression. Nonetheless, a number of observations suggest that our understanding of developmental cell death in C. elegans is incomplete. The interaction between dying and engulfing cells seems to be more complex than originally appreciated, and it appears that key aspects of cell death initiation are not fully understood. It has also become apparent that the conserved apoptotic pathway is dispensable for the demise of the C. elegans linker cell, leading to the discovery of a previously unexplored gene program promoting cell death. Here, we review studies that formed the foundation of cell death research in C. elegans and describe new observations that expand, and in some cases remodel, this edifice. We raise the possibility that, in some cells, more than one death program may be needed to ensure cell death fidelity.
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Affiliation(s)
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, New York, USA.
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18
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Sánchez-Blanco A, Rodríguez-Matellán AG, Reis-Sobreiro M, Sáenz-Narciso B, Cabello J, Mohler WA, Mollinedo F. Caenorhabditis elegans as a platform to study the mechanism of action of synthetic antitumor lipids. Cell Cycle 2015; 13:3375-89. [PMID: 25485582 DOI: 10.4161/15384101.2014.952183] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Drugs capable of specifically recognizing and killing cancer cells while sparing healthy cells are of great interest in anti-cancer therapy. An example of such a drug is edelfosine, the prototype molecule of a family of synthetic lipids collectively known as antitumor lipids (ATLs). A better understanding of the selectivity and the mechanism of action of these compounds would lead to better anticancer treatments. Using Caenorhabditis elegans, we modeled key features of the ATL selectivity against cancer cells. Edelfosine induced a selective and direct killing action on C. elegans embryos, which was dependent on cholesterol, without affecting adult worms and larvae. Distinct ATLs ranked differently in their embryonic lethal effect with edelfosine > perifosine > erucylphosphocholine >> miltefosine. Following a biased screening of 57 C. elegans mutants we found that inactivation of components of the insulin/IGF-1 signaling pathway led to resistance against the ATL edelfosine in both C. elegans and human tumor cells. This paper shows that C. elegans can be used as a rapid platform to facilitate ATL research and to further understand the mechanism of action of edelfosine and other synthetic ATLs.
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Affiliation(s)
- Adolfo Sánchez-Blanco
- a Instituto de Biología Molecular y Celular del Cáncer ; Centro de Investigación del Cáncer ; CSIC-Universidad de Salamanca ; Campus Miguel de Unamuno ; Salamanca , Spain
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19
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Cabello J, Sämann J, Gómez-Orte E, Erazo T, Coppa A, Pujol A, Büssing I, Schulze B, Lizcano JM, Ferrer I, Baumeister R, Dalfo E. PDR-1/hParkin negatively regulates the phagocytosis of apoptotic cell corpses in Caenorhabditis elegans. Cell Death Dis 2014; 5:e1120. [PMID: 24625979 PMCID: PMC3973248 DOI: 10.1038/cddis.2014.57] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/23/2013] [Accepted: 01/22/2014] [Indexed: 12/28/2022]
Abstract
Apoptotic cell death is an integral part of cell turnover in many tissues, and proper corpse clearance is vital to maintaining tissue homeostasis in all multicellular organisms. Even in tissues with high cellular turnover, apoptotic cells are rarely seen because of efficient clearance mechanisms in healthy individuals. In Caenorhabditis elegans, two parallel and partly redundant conserved pathways act in cell corpse engulfment. The pathway for cytoskeletal rearrangement requires the small GTPase CED-10 Rac1 acting for an efficient surround of the dead cell. The CED-10 Rac pathway is also required for the proper migration of the distal tip cells (DTCs) during the development of the C. elegans gonad. Parkin, the mammalian homolog of the C. elegans PDR-1, interacts with Rac1 in aged human brain and it is also implicated with actin dynamics and cytoskeletal rearrangements in Parkinsons's disease, suggesting that it might act on engulfment. Our genetic and biochemical studies indicate that PDR-1 inhibits apoptotic cell engulfment and DTC migration by ubiquitylating CED-10 for degradation.
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Affiliation(s)
- J Cabello
- CIBIR (Centre for Biomedical Research of La Rioja), C/Piqueras 98, Logroño 26006, Spain
| | - J Sämann
- Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry and Molecular Cell Research (Faculty of Medicine), Schänzlestrasse 1, Freiburg 79104, Germany
| | - E Gómez-Orte
- CIBIR (Centre for Biomedical Research of La Rioja), C/Piqueras 98, Logroño 26006, Spain
| | - T Erazo
- Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallés, Barcelona 08193, Spain
| | - A Coppa
- Neurometabolic Diseases Laboratory, Institut D'Investigació Biomèdica de Bellvitge (IDIBELL), Hospital Duran i Reynals, L'Hospitalet de Llobregat, Barcelona 08907, Spain
| | - A Pujol
- 1] Neurometabolic Diseases Laboratory, Institut D'Investigació Biomèdica de Bellvitge (IDIBELL), Hospital Duran i Reynals, L'Hospitalet de Llobregat, Barcelona 08907, Spain [2] ICREA (Institució Catalana de Recerca i Estudis avançats), Barcelona, Spain [3] Institute of Neuropathology, University Hospitall Bellvitge - University of Barcelona - IDIBELL, L'Hospitalet de Llobregat, Ciberned, Spain [4] CIBERER (Centro de Investigación Biomédica en Enfermedades Raras), C/ Álvaro de Bazán, 10 Bajo, Valencia 46010, Spain
| | - I Büssing
- Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry and Molecular Cell Research (Faculty of Medicine), Schänzlestrasse 1, Freiburg 79104, Germany
| | - B Schulze
- Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry and Molecular Cell Research (Faculty of Medicine), Schänzlestrasse 1, Freiburg 79104, Germany
| | - J M Lizcano
- Institut de Neurociències, Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Cerdanyola del Vallés, Barcelona 08193, Spain
| | - I Ferrer
- Institute of Neuropathology, University Hospitall Bellvitge - University of Barcelona - IDIBELL, L'Hospitalet de Llobregat, Ciberned, Spain
| | - R Baumeister
- 1] Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry and Molecular Cell Research (Faculty of Medicine), Schänzlestrasse 1, Freiburg 79104, Germany [2] Centre for Biological Signaling Studies (bioss), University of Freiburg, Freiburg 79104, Germany [3] FRIAS Freiburg Institute for Advanced Studies, Section Life Sciences (LIFENET), University of Freiburg, Schaenzlestrasse 1, Freiburg 79104, Germany
| | - E Dalfo
- 1] Bioinformatics and Molecular Genetics (Faculty of Biology), Center for Biochemistry and Molecular Cell Research (Faculty of Medicine), Schänzlestrasse 1, Freiburg 79104, Germany [2] Neurometabolic Diseases Laboratory, Institut D'Investigació Biomèdica de Bellvitge (IDIBELL), Hospital Duran i Reynals, L'Hospitalet de Llobregat, Barcelona 08907, Spain [3] Institute of Neuropathology, University Hospitall Bellvitge - University of Barcelona - IDIBELL, L'Hospitalet de Llobregat, Ciberned, Spain [4] CIBERER (Centro de Investigación Biomédica en Enfermedades Raras), C/ Álvaro de Bazán, 10 Bajo, Valencia 46010, Spain
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20
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Jiménez-Hidalgo M, Kurz CL, Pedrajas JR, Naranjo-Galindo FJ, González-Barrios M, Cabello J, Sáez AG, Lozano E, Button EL, Veal EA, Fierro-González JC, Swoboda P, Miranda-Vizuete A. Functional characterization of thioredoxin 3 (TRX-3), a Caenorhabditis elegans intestine-specific thioredoxin. Free Radic Biol Med 2014; 68:205-19. [PMID: 24316195 PMCID: PMC4018987 DOI: 10.1016/j.freeradbiomed.2013.11.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 11/13/2013] [Accepted: 11/22/2013] [Indexed: 01/15/2023]
Abstract
Thioredoxins are a class of evolutionarily conserved proteins that have been demonstrated to play a key role in many cellular processes involving redox reactions. We report here the genetic and biochemical characterization of Caenorhabditis elegans TRX-3, the first metazoan thioredoxin with an intestine-specific expression pattern. By using green fluorescent protein reporters we have found that TRX-3 is expressed in both the cytoplasm and the nucleus of intestinal cells, with a prominent localization at the apical membrane. Although intestinal function, reproductive capacity, longevity, and resistance of trx-3 loss-of-function mutants to many stresses are indistinguishable from those of wild-type animals, we have observed a slight reduction in size and a minor reduction in the defecation cycle timing of trx-3 mutants. Interestingly, trx-3 is induced upon infection by Photorhabdus luminescens and Candida albicans, and TRX-3 overexpression provides a modest protection against these pathogens. Together, our data indicate that TRX-3 function in the intestine is dispensable for C. elegans development but may be important to fight specific bacterial and fungal infections.
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Affiliation(s)
- María Jiménez-Hidalgo
- Centro Andaluz de Biología del Desarrollo, Departamento de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - Cyril Léopold Kurz
- Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Case 906, 13288 Marseille cedex 9, France
| | - José Rafael Pedrajas
- Grupo de Bioquímica y Señalización Celular, Departamento de Biología Experimental, Universidad de Jaén, 23071 Jaén, Spain
| | - Francisco José Naranjo-Galindo
- Centro Andaluz de Biología del Desarrollo, Departamento de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - María González-Barrios
- Centro Andaluz de Biología del Desarrollo, Departamento de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, 41013 Sevilla, Spain
| | - Juan Cabello
- Center for Biomedical Research of La Rioja, 26006 Logroño, Spain
| | - Alberto G Sáez
- Unidad Funcional de Investigación en Enfermedades Crónicas, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain
| | - Encarnación Lozano
- Unidad Funcional de Investigación en Enfermedades Crónicas, Instituto de Salud Carlos III, 28220 Majadahonda, Madrid, Spain
| | - Emma L Button
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Elizabeth A Veal
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Juan Carlos Fierro-González
- Center for Biosciences at Novum, Department of Biosciences and Nutrition, Karolinska Institute, S-14183 Huddinge, Sweden
| | - Peter Swoboda
- Center for Biosciences at Novum, Department of Biosciences and Nutrition, Karolinska Institute, S-14183 Huddinge, Sweden
| | - Antonio Miranda-Vizuete
- Centro Andaluz de Biología del Desarrollo, Departamento de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, 41013 Sevilla, Spain; Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain.
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21
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Delahaye JL, Foster OK, Vine A, Saxton DS, Curtin TP, Somhegyi H, Salesky R, Hermann GJ. Caenorhabditis elegans HOPS and CCZ-1 mediate trafficking to lysosome-related organelles independently of RAB-7 and SAND-1. Mol Biol Cell 2014; 25:1073-96. [PMID: 24501423 PMCID: PMC3967972 DOI: 10.1091/mbc.e13-09-0521] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
As early endosomes mature, the SAND-1/CCZ-1 complex acts as a guanine nucleotide exchange factor (GEF) for RAB-7 to promote the activity of its effector, HOPS, which facilitates late endosome-lysosome fusion and the consumption of AP-3-containing vesicles. We show that CCZ-1 and the HOPS complex are essential for the biogenesis of gut granules, cell type-specific, lysosome-related organelles (LROs) that coexist with conventional lysosomes in Caenorhabditis elegans intestinal cells. The HOPS subunit VPS-18 promotes the trafficking of gut granule proteins away from lysosomes and functions downstream of or in parallel to the AP-3 adaptor. CCZ-1 also acts independently of AP-3, and ccz-1 mutants mistraffic gut granule proteins. Our results indicate that SAND-1 does not participate in the formation of gut granules. In the absence of RAB-7 activity, gut granules are generated; however, their size and protein composition are subtly altered. These observations suggest that CCZ-1 acts in partnership with a protein other than SAND-1 as a GEF for an alternate Rab to promote gut granule biogenesis. Point mutations in GLO-1, a Rab32/38-related protein, predicted to increase spontaneous guanine nucleotide exchange, specifically suppress the loss of gut granules by ccz-1 and glo-3 mutants. GLO-3 is known to be required for gut granule formation and has homology to SAND-1/Mon1-related proteins, suggesting that CCZ-1 functions with GLO-3 upstream of the GLO-1 Rab, possibly as a GLO-1 GEF. These results support LRO formation occurring via processes similar to conventional lysosome biogenesis, albeit with key molecular differences.
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Affiliation(s)
- Jared L Delahaye
- Department of Biology, Lewis & Clark College, Portland, OR 97219 Program in Biochemistry and Molecular Biology, Lewis & Clark College, Portland, OR 97219
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22
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Inhibition of late endosomal maturation restores Wnt secretion in Caenorhabditis elegans vps-29 retromer mutants. Cell Signal 2014; 26:19-31. [DOI: 10.1016/j.cellsig.2013.09.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 09/05/2013] [Accepted: 09/13/2013] [Indexed: 01/01/2023]
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23
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Pinto SM, Hengartner MO. Cleaning up the mess: cell corpse clearance in Caenorhabditis elegans. Curr Opin Cell Biol 2012. [PMID: 23206434 DOI: 10.1016/j.ceb.2012.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Genetic and cell biology studies have led to the identification in Caenorhabditis elegans of a set of evolutionary conserved cellular mechanisms responsible for the clearance of apoptotic cells. Based on the phenotype of cell corpse clearance mutants, corpse clearance can be divided into three distinct, but linked steps: corpse recognition, corpse internalization, and corpse degradation. Work in recent years has led to a better understanding of the molecular pathways that mediate each of these steps. Here, we review recent developments in our understanding of in vivo cell corpse clearance in this simple but most elegant model organism.
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Affiliation(s)
- Sérgio Morgado Pinto
- Institute of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland; Graduate Program in Areas of Basic and Applied Biology (GABBA), Universidade do Porto, Porto, Portugal
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24
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Cacho-Valadez B, Muñoz-Lobato F, Pedrajas JR, Cabello J, Fierro-González JC, Navas P, Swoboda P, Link CD, Miranda-Vizuete A. The characterization of the Caenorhabditis elegans mitochondrial thioredoxin system uncovers an unexpected protective role of thioredoxin reductase 2 in β-amyloid peptide toxicity. Antioxid Redox Signal 2012; 16:1384-400. [PMID: 22220943 PMCID: PMC3329951 DOI: 10.1089/ars.2011.4265] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
AIM Functional in vivo studies on the mitochondrial thioredoxin system are hampered by the embryonic or larval lethal phenotypes displayed by murine or Drosophila knock-out models. Thus, the access to alternative metazoan knock-out models for the mitochondrial thioredoxin system is of critical importance. RESULTS We report here the characterization of the mitochondrial thioredoxin system of Caenorhabditis elegans that is composed of the genes trx-2 and trxr-2. We demonstrate that the proteins thioredoxin 2 (TRX-2) and thioredoxin reductase 2 (TRXR-2) localize to the mitochondria of several cells and tissues of the nematode and that trx-2 and trxr-2 are upregulated upon induction of the mitochondrial unfolded protein response. Surprisingly, C. elegans trx-2 (lof ) and trxr-2 (null) single and double mutants are viable and display similar growth rates as wild-type controls. Moreover, the lack of the mitochondrial thioredoxin system does not affect longevity, reactive oxygen species production or the apoptotic program. Interestingly, we found a protective role of TRXR-2 in a transgenic nematode model of Alzheimer's disease (AD) that expresses human β-amyloid peptide and causes an age-dependent progressive paralysis. Hence, trxr-2 downregulation enhanced the paralysis phenotype, while a strong decrease of β-amyloid peptide and amyloid deposits occurred when TRXR-2 was overexpressed. INNOVATION C. elegans provides the first viable metazoan knock-out model for the mitochondrial thioredoxin system and identifies a novel role of this system in β-amyloid peptide toxicity and AD. CONCLUSION The nematode strains characterized in this work make C. elegans an ideal model organism to study the pathophysiology of the mitochondrial thioredoxin system at the level of a complete organism.
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Affiliation(s)
- Briseida Cacho-Valadez
- Centro Andaluz de Biología del Desarrollo (CABD-CSIC), Depto. de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide, Sevilla, Spain
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25
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Lu N, Zhou Z. Membrane trafficking and phagosome maturation during the clearance of apoptotic cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 293:269-309. [PMID: 22251564 PMCID: PMC3551535 DOI: 10.1016/b978-0-12-394304-0.00013-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Apoptosis is a cellular suicide process that quietly and efficiently eliminates unwanted or damaged cells. In metazoans, cells that undergo apoptosis are swiftly internalized by phagocytes and subsequently degraded inside phagosomes through phagosome maturation, a process that involves the fusion between phagosomes and multiple kinds of intracellular organelles and the gradual acidification of phagosomal lumen. In recent years, rapid progress has been made, in particular, through studies conducted in the model organism, the nematode Caenorhabditis elegans, in understanding the membrane trafficking events and molecular mechanisms that govern the degradation of apoptotic cells through phagosome maturation. These studies revealed the novel and essential functions of a large number of proteins, including the large GTPase dynamin, multiple Rab small GTPases and their regulatory proteins, the lipid second messenger PtdIns(3)P and its effectors, and unexpectedly, the phagosomal receptors for apoptotic cells, in promoting phagosome maturation. Further, novel signaling pathways essential for phagosome maturation have been delineated. Here, we discuss these exciting new findings, which have significantly deepened and broadened our understanding of the mechanisms that regulate the interaction between intracellular organelles and phagosomes.
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Affiliation(s)
- Nan Lu
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
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26
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Microtubule-associated protein 1 light chain 3 alpha (LC3)-associated phagocytosis is required for the efficient clearance of dead cells. Proc Natl Acad Sci U S A 2011; 108:17396-401. [PMID: 21969579 DOI: 10.1073/pnas.1113421108] [Citation(s) in RCA: 532] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The recognition and clearance of dead cells is a process that must occur efficiently to prevent an autoimmune or inflammatory response. Recently, a process was identified wherein the autophagy machinery is recruited to pathogen-containing phagosomes, termed MAPLC3A (LC3)-associated phagocytosis (LAP), which results in optimal degradation of the phagocytosed cargo. Here, we describe the engagement of LAP upon uptake of apoptotic, necrotic, and RIPK3-dependent necrotic cells by macrophages. This process is dependent on some members of the classical autophagy pathway, including Beclin1, ATG5, and ATG7. In contrast, ULK1, despite being required for autophagy, is dispensable for LAP induced by uptake of microbes or dead cells. LAP is required for efficient degradation of the engulfed corpse, and in the absence of LAP, engulfment of dead cells results in increased production of proinflammatory cytokines and decreased production of anti-inflammatory cytokines. LAP is triggered by engagement of the TIM4 receptor by either phosphatidylserine (PtdSer)-displaying dead cells or PtdSer-containing liposomes. Therefore, the consequence of phagocytosis of dead cells is strongly affected by those components of the autophagy pathway involved in LAP.
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Neukomm LJ, Nicot AS, Kinchen JM, Almendinger J, Pinto SM, Zeng S, Doukoumetzidis K, Tronchère H, Payrastre B, Laporte JF, Hengartner MO. The phosphoinositide phosphatase MTM-1 regulates apoptotic cell corpse clearance through CED-5–CED-12 in C. elegans. Development 2011; 138:2003-14. [DOI: 10.1242/dev.060012] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Multicellular organisms use programmed cell death to eliminate unwanted or potentially harmful cells. Improper cell corpse removal can lead to autoimmune diseases. The development of interventional therapies that increase engulfment activity could represent an attractive approach to treat such diseases. Here, we describe mtm-1, the Caenorhabditis elegans homolog of human myotubularin 1, as a potential negative regulator of apoptotic cell corpse clearance. Loss of mtm-1 function leads to substantially reduced numbers of persistent cell corpses in engulfment mutants, which is a result of a restoration of engulfment function rather than of impaired or delayed programmed cell death. Epistatic analyses place mtm-1 upstream of the ternary GEF complex, which consists of ced-2, ced-5 and ced-12, and parallel to mig-2. Over-activation of engulfment results in the removal of viable cells that have been brought to the verge of death under limiting caspase activity. In addition, mtm-1 also promotes phagosome maturation in the hermaphrodite gonad, potentially through CED-1 receptor recycling. Finally, we show that the CED-12 PH domain can bind to PtdIns(3,5)P2 (one target of MTM-1 phosphatase activity), suggesting that MTM-1 might regulate CED-12 recruitment to the plasma membrane.
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Affiliation(s)
- Lukas Jakob Neukomm
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Anne-Sophie Nicot
- Department of Translational Medecine and Neurogenetics, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale U964, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7104, Université de Strasbourg, Collège de France, 67404 Illkirch, France
| | | | - Johann Almendinger
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Sérgio Morgado Pinto
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Sheng Zeng
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Kimon Doukoumetzidis
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Hélène Tronchère
- INSERM, U1048, Université Toulouse III Paul Sabatier, I2MC, CHU de Toulouse, Laboratoire d'Hématologie, 31432 Toulouse cedex 4, France
| | - Bernard Payrastre
- INSERM, U1048, Université Toulouse III Paul Sabatier, I2MC, CHU de Toulouse, Laboratoire d'Hématologie, 31432 Toulouse cedex 4, France
| | - Jocelyn Franck Laporte
- Department of Translational Medecine and Neurogenetics, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de la Santé et de la Recherche Médicale U964, Centre National de la Recherche Scientifique Unité Mixte de Recherche 7104, Université de Strasbourg, Collège de France, 67404 Illkirch, France
| | - Michael Otmar Hengartner
- Institute of Molecular Life Science, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
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Almendinger J, Doukoumetzidis K, Kinchen JM, Kaech A, Ravichandran KS, Hengartner MO. A conserved role for SNX9-family members in the regulation of phagosome maturation during engulfment of apoptotic cells. PLoS One 2011; 6:e18325. [PMID: 21494661 PMCID: PMC3072968 DOI: 10.1371/journal.pone.0018325] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 03/02/2011] [Indexed: 12/02/2022] Open
Abstract
Clearance of apoptotic cells is of key importance during development, tissue homeostasis and wound healing in multi-cellular animals. Genetic studies in the nematode Caenorhabditis elegans have identified a set of genes involved in the early steps of cell clearance, in particular the recognition and internalization of apoptotic cells. A pathway that orchestrates the maturation of phagosomes containing ingested apoptotic cells in the worm has recently been described. However, many steps in this pathway remain elusive. Here we show that the C. elegans SNX9-family member LST-4 (lateral signaling target) and its closest mammalian orthologue SNX33 play an evolutionary conserved role during apoptotic cell corpse clearance. In lst-4 deficient worms, internalized apoptotic cells accumulated within non-acidified, DYN-1-positive but RAB-5-negative phagosomes. Genetically, we show that LST-4 functions at the same step as DYN-1 during corpse removal, upstream of the GTPase RAB-5. We further show that mammalian SNX33 rescue C. elegans lst-4 mutants and that overexpression of truncated SNX33 fragments interfered with phagosome maturation in a mammalian cell system. Taken together, our genetic and cell biological analyses suggest that LST-4 is recruited through a combined activity of DYN-1 and VPS-34 to the early phagosome membrane, where it cooperates with DYN-1 to promote recruitment/retention of RAB-5 on the early phagosomal membrane during cell corpse clearance. The functional conservation between LST-4 and SNX33 indicate that these early steps of apoptotic phagosome maturation are likely conserved through evolution.
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Affiliation(s)
- Johann Almendinger
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.
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