1
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Cai R, Scott O, Ye G, Le T, Saran E, Kwon W, Inpanathan S, Sayed BA, Botelho RJ, Saric A, Uderhardt S, Freeman SA. Pressure sensing of lysosomes enables control of TFEB responses in macrophages. Nat Cell Biol 2024:10.1038/s41556-024-01459-y. [PMID: 38997458 DOI: 10.1038/s41556-024-01459-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 06/11/2024] [Indexed: 07/14/2024]
Abstract
Polymers are endocytosed and hydrolysed by lysosomal enzymes to generate transportable solutes. While the transport of diverse organic solutes across the plasma membrane is well studied, their necessary ongoing efflux from the endocytic fluid into the cytosol is poorly appreciated by comparison. Myeloid cells that employ specialized types of endocytosis, that is, phagocytosis and macropinocytosis, are highly dependent on such transport pathways to prevent the build-up of hydrostatic pressure that otherwise offsets lysosomal dynamics including vesiculation, tubulation and fission. Without undergoing rupture, we found that lysosomes incurring this pressure owing to defects in solute efflux, are unable to retain luminal Na+, which collapses its gradient with the cytosol. This cation 'leak' is mediated by pressure-sensitive channels resident to lysosomes and leads to the inhibition of mTORC1, which is normally activated by Na+-coupled amino acid transporters driven by the Na+ gradient. As a consequence, the transcription factors TFEB/TFE3 are made active in macrophages with distended lysosomes. In addition to their role in lysosomal biogenesis, TFEB/TFE3 activation causes the release of MCP-1/CCL2. In catabolically stressed tissues, defects in efflux of solutes from the endocytic pathway leads to increased monocyte recruitment. Here we propose that macrophages respond to a pressure-sensing pathway on lysosomes to orchestrate lysosomal biogenesis as well as myeloid cell recruitment.
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Affiliation(s)
- Ruiqi Cai
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ori Scott
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Gang Ye
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Trieu Le
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ekambir Saran
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Whijin Kwon
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Subothan Inpanathan
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
- Molecular Science Graduate Program, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Blayne A Sayed
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Roberto J Botelho
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
- Molecular Science Graduate Program, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Amra Saric
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- Program in Neurosciences and Mental Health, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Stefan Uderhardt
- Department of Internal Medicine, Rheumatology and Immunology, Universitätsklinikum Erlangen, Friedrich-Alexander University Erlangen, Erlangen, Germany
- Deutsches Zentrum für Immuntherapie, Universitätsklinikum Erlangen, Friedrich-Alexander University Erlangen, Erlangen, Germany
- Exploratory Research Unit, Optical Imaging Centre Erlangen, Friedrich-Alexander University Erlangen, Erlangen, Germany
| | - Spencer A Freeman
- Program in Cell Biology and Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, Ontario, Canada.
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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2
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Bonini S, Winter D. Two-Step Enrichment Facilitates Background Reduction for Proteomic Analysis of Lysosomes. J Proteome Res 2024. [PMID: 38967832 DOI: 10.1021/acs.jproteome.4c00053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
Lysosomes constitute the main degradative compartment of most mammalian cells and are involved in various cellular functions. Most of them are catalyzed by lysosomal proteins, which typically are low abundant, complicating their analysis by mass spectrometry-based proteomics. To increase analytical performance and to enable profiling of lysosomal content, lysosomes are often enriched. Two approaches have gained popularity in recent years, namely, superparamagnetic iron oxide nanoparticles (SPIONs) and immunoprecipitation from cells overexpressing a 3xHA-tagged version of TMEM192 (TMEM-IP). The effect of these approaches on the lysosomal proteome has not been investigated to date. We addressed this topic through a combination of both techniques and proteomic analysis of lysosome-enriched fractions. For SPIONs treatment, we identified altered cellular iron homeostasis and moderate changes of the lysosomal proteome. For overexpression of TMEM192, we observed more pronounced effects in lysosomal protein expression, especially for lysosomal membrane proteins and those involved in protein trafficking. Furthermore, we established a combined strategy based on the sequential enrichment of lysosomes with SPIONs and TMEM-IP. This enabled increased purity of lysosome-enriched fractions and, through TMEM-IP-based lysosome enrichment from SPIONs flow-through and eluate fractions, additional insights into the properties of individual approaches. All data are available via ProteomeXchange with PXD048696.
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Affiliation(s)
- Sara Bonini
- Institute for Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn 53115, Germany
| | - Dominic Winter
- Institute for Biochemistry and Molecular Biology, Medical Faculty, University of Bonn, Bonn 53115, Germany
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3
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Johnson D, Colijn S, Richee J, Yano J, Burns M, Davis AE, Pham VN, Saric A, Jain A, Yin Y, Castranova D, Melani M, Fujita M, Grainger S, Bonifacino JS, Weinstein BM, Stratman AN. Regulation of angiogenesis by endocytic trafficking mediated by cytoplasmic dynein 1 light intermediate chain 1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.01.587559. [PMID: 38903077 PMCID: PMC11188074 DOI: 10.1101/2024.04.01.587559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Dynein cytoplasmic 1 light intermediate chain 1 (LIC1, DYNC1LI1) is a core subunit of the dynein motor complex. The LIC1 subunit also interacts with various cargo adaptors to regulate Rab-mediated endosomal recycling and lysosomal degradation. Defects in this gene are predicted to alter dynein motor function, Rab binding capabilities, and cytoplasmic cargo trafficking. Here, we have identified a dync1li1 zebrafish mutant, harboring a premature stop codon at the exon 12/13 splice acceptor site, that displays increased angiogenesis. In vitro, LIC1-deficient human endothelial cells display increases in cell surface levels of the pro-angiogenic receptor VEGFR2, SRC phosphorylation, and Rab11-mediated endosomal recycling. In vivo, endothelial-specific expression of constitutively active Rab11a leads to excessive angiogenesis, similar to the dync1li1 mutants. Increased angiogenesis is also evident in zebrafish harboring mutations in rilpl1/2, the adaptor proteins that promote Rab docking to Lic1 to mediate lysosomal targeting. These findings suggest that LIC1 and the Rab-adaptor proteins RILPL1 and 2 restrict angiogenesis by promoting degradation of VEGFR2-containing recycling endosomes. Disruption of LIC1- and RILPL1/2-mediated lysosomal targeting increases Rab11-mediated recycling endosome activity, promoting excessive SRC signaling and angiogenesis.
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Affiliation(s)
- Dymonn Johnson
- Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Sarah Colijn
- Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Jahmiera Richee
- Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Joseph Yano
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
- Cell and Molecular Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Margaret Burns
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Andrew E. Davis
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Van N. Pham
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Amra Saric
- Section on Intracellular Protein Trafficking, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
- Neurosciences and Mental Health Program, Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada
| | - Akansha Jain
- Section on Intracellular Protein Trafficking, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Ying Yin
- Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
| | - Daniel Castranova
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Mariana Melani
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
- Fundación Instituto Leloir, Buenos Aires, Argentina
- Consejo Nacional De Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina
- Departamento De Fisiología, Biología Molecular Y Celular, Facultad De Ciencias Exactas Y Naturales, Universidad De Buenos Aires, Buenos Aires, Argentina
| | - Misato Fujita
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
- Kanagawa University, Kanagawa, 221-8686, Japan
| | - Stephanie Grainger
- Department of Cell Biology, Van Andel Institute, Grand Rapids, MI, 49503
| | - Juan S. Bonifacino
- Section on Intracellular Protein Trafficking, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Brant M. Weinstein
- Section on Vertebrate Organogenesis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892
| | - Amber N. Stratman
- Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110
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4
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Settembre C, Perera RM. Lysosomes as coordinators of cellular catabolism, metabolic signalling and organ physiology. Nat Rev Mol Cell Biol 2024; 25:223-245. [PMID: 38001393 DOI: 10.1038/s41580-023-00676-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2023] [Indexed: 11/26/2023]
Abstract
Every cell must satisfy basic requirements for nutrient sensing, utilization and recycling through macromolecular breakdown to coordinate programmes for growth, repair and stress adaptation. The lysosome orchestrates these key functions through the synchronised interplay between hydrolytic enzymes, nutrient transporters and signalling factors, which together enable metabolic coordination with other organelles and regulation of specific gene expression programmes. In this Review, we discuss recent findings on lysosome-dependent signalling pathways, focusing on how the lysosome senses nutrient availability through its physical and functional association with mechanistic target of rapamycin complex 1 (mTORC1) and how, in response, the microphthalmia/transcription factor E (MiT/TFE) transcription factors exert feedback regulation on lysosome biogenesis. We also highlight the emerging interactions of lysosomes with other organelles, which contribute to cellular homeostasis. Lastly, we discuss how lysosome dysfunction contributes to diverse disease pathologies and how inherited mutations that compromise lysosomal hydrolysis, transport or signalling components lead to multi-organ disorders with severe metabolic and neurological impact. A deeper comprehension of lysosomal composition and function, at both the cellular and organismal level, may uncover fundamental insights into human physiology and disease.
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Affiliation(s)
- Carmine Settembre
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.
- Department of Clinical Medicine and Surgery, Federico II University, Naples, Italy.
| | - Rushika M Perera
- Department of Anatomy, University of California at San Francisco, San Francisco, CA, USA.
- Department of Pathology, University of California at San Francisco, San Francisco, CA, USA.
- Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, CA, USA.
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5
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Jerabkova-Roda K, Marwaha R, Das T, Goetz JG. Organelle morphology and positioning orchestrate physiological and disease-associated processes. Curr Opin Cell Biol 2024; 86:102293. [PMID: 38096602 DOI: 10.1016/j.ceb.2023.102293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/24/2023] [Accepted: 11/19/2023] [Indexed: 02/15/2024]
Abstract
In cells, organelles are distributed nonrandomly to regulate cells' physiological and disease-associated processes. Based on their morphology, position within the cell, and contacts with other organelles, they exert different biological functions. Endo-lysosomes are critical cell metabolism and nutrient-sensing regulators modulating cell growth and cellular adaptation in response to nutrient availability. Their spatial distribution is intimately linked to their function. In this review, we will discuss the role of endolysosomes under physiological conditions and in the context of cancer progression, with a special focus on their morphology, the molecular mechanisms determining their subcellular position, and the contacts they form with other organelles. We aim to highlight the relationship between cell architecture and cell function and its impact on maintaining organismal homeostasis.
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Affiliation(s)
- Katerina Jerabkova-Roda
- Tumor Biomechanics, INSERM UMR_S1109, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France; Equipe Labellisée Ligue Contre le Cancer, France.
| | - Rituraj Marwaha
- Tata Institute of Fundamental Research Hyderabad (TIFR-H), Hyderabad, 500 046, India
| | - Tamal Das
- Tata Institute of Fundamental Research Hyderabad (TIFR-H), Hyderabad, 500 046, India
| | - Jacky G Goetz
- Tumor Biomechanics, INSERM UMR_S1109, Strasbourg, France; Université de Strasbourg, Strasbourg, France; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France; Equipe Labellisée Ligue Contre le Cancer, France
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6
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Kumar R, Khan M, Francis V, Aguila A, Kulasekaran G, Banks E, McPherson PS. DENND6A links Arl8b to a Rab34/RILP/dynein complex, regulating lysosomal positioning and autophagy. Nat Commun 2024; 15:919. [PMID: 38296963 PMCID: PMC10830484 DOI: 10.1038/s41467-024-44957-1] [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: 08/21/2023] [Accepted: 01/08/2024] [Indexed: 02/02/2024] Open
Abstract
Lysosomes help maintain cellular proteostasis, and defects in lysosomal positioning and function can cause disease, including neurodegenerative disorders. The spatiotemporal distribution of lysosomes is regulated by small GTPases including Rabs, which are activated by guanine nucleotide exchange factors (GEFs). DENN domain proteins are the largest family of Rab GEFs. Using a cell-based assay, we screened DENND6A, a member of the DENN domain protein family against all known Rabs and identified it as a potential GEF for 20 Rabs, including Rab34. Here, we demonstrate that DENND6A activates Rab34, which recruits a RILP/dynein complex to lysosomes, promoting lysosome retrograde transport. Further, we identify DENND6A as an effector of Arl8b, a major regulatory GTPase on lysosomes. We demonstrate that Arl8b recruits DENND6A to peripheral lysosomes to activate Rab34 and initiate retrograde transport, regulating nutrient-dependent lysosomal juxtanuclear repositioning. Loss of DENND6A impairs autophagic flux. Our findings support a model whereby Arl8b/DENND6A/Rab34-dependent lysosomal retrograde trafficking controls autophagy.
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Affiliation(s)
- Rahul Kumar
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada.
| | - Maleeha Khan
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada
| | - Vincent Francis
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada
| | - Adriana Aguila
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada
| | - Gopinath Kulasekaran
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada
| | - Emily Banks
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute (the Neuro), McGill University, Montreal, QC, Canada.
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7
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Pierga A, Matusiak R, Cauhapé M, Branchu J, Danglot L, Boutry M, Darios F. Spatacsin regulates directionality of lysosome trafficking by promoting the degradation of its partner AP5Z1. PLoS Biol 2023; 21:e3002337. [PMID: 37871017 PMCID: PMC10621996 DOI: 10.1371/journal.pbio.3002337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 11/02/2023] [Accepted: 09/15/2023] [Indexed: 10/25/2023] Open
Abstract
The endoplasmic reticulum (ER) forms contacts with the lysosomal compartment, regulating lysosome positioning and motility. The movements of lysosomes are controlled by the attachment of molecular motors to their surface. However, the molecular mechanisms by which ER controls lysosome dynamics are still elusive. Here, using mouse brain extracts and mouse embryonic fibroblasts, we demonstrate that spatacsin is an ER-resident protein regulating the formation of tubular lysosomes, which are highly dynamic. Screening for spatacsin partners required for tubular lysosome formation showed spatacsin to act by regulating protein degradation. We demonstrate that spatacsin promotes the degradation of its partner AP5Z1, which regulates the relative amount of spastizin and AP5Z1 at lysosomes. Spastizin and AP5Z1 contribute to regulate tubular lysosome formation, as well as their trafficking by interacting with anterograde and retrograde motor proteins, kinesin KIF13A and dynein/dynactin subunit p150Glued, respectively. Ultimately, investigations in polarized mouse cortical neurons in culture demonstrated that spatacsin-regulated degradation of AP5Z1 controls the directionality of lysosomes trafficking. Collectively, our results identify spatacsin as a protein regulating the directionality of lysosome trafficking.
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Affiliation(s)
- Alexandre Pierga
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Raphaël Matusiak
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Margaux Cauhapé
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Julien Branchu
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Lydia Danglot
- Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Membrane Traffic in Healthy and Diseased Brain, Université Paris Cité, Paris, France
- Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Scientific director of NeurImag facility, Université Paris Cité, Paris, France
| | - Maxime Boutry
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
| | - Frédéric Darios
- Sorbonne Université, Paris, France
- Paris Brain Institute, ICM, Paris, France
- Inserm, U1127, Paris, France
- CNRS, UMR 7225, Paris, France
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8
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Boutry M, DiGiovanni LF, Demers N, Fountain A, Mamand S, Botelho RJ, Kim PK. Arf1-PI4KIIIβ positive vesicles regulate PI(3)P signaling to facilitate lysosomal tubule fission. J Cell Biol 2023; 222:e202205128. [PMID: 37289133 PMCID: PMC10250553 DOI: 10.1083/jcb.202205128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 04/03/2023] [Accepted: 05/22/2023] [Indexed: 06/09/2023] Open
Abstract
Formation and fission of tubules from autolysosomes, endolysosomes, or phagolysosomes are required for lysosome reformation. However, the mechanisms governing these processes in these different lysosomal organelles are poorly understood. Thus, the role of phosphatidylinositol-4-phosphate (PI(4)P) is unclear as it was shown to promote the formation of tubules from phagolysosomes but was proposed to inhibit tubule formation on autolysosomes because the loss of PI4KIIIβ causes extensive lysosomal tubulation. Using super-resolution live-cell imaging, we show that Arf1-PI4KIIIβ positive vesicles are recruited to tubule fission sites from autolysosomes, endolysosomes, and phagolysosomes. Moreover, we show that PI(4)P is required to form autolysosomal tubules and that increased lysosomal tubulation caused by loss of PI4KIIIβ represents impaired tubule fission. At the site of fission, we propose that Arf1-PI4KIIIβ positive vesicles mediate a PI(3)P signal on lysosomes in a process requiring the lipid transfer protein SEC14L2. Our findings indicate that Arf1-PI4KIIIβ positive vesicles and their regulation of PI(3)P are critical components of the lysosomal tubule fission machinery.
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Affiliation(s)
- Maxime Boutry
- Cell Biology Program, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
| | - Laura F. DiGiovanni
- Cell Biology Program, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Nicholas Demers
- Cell Biology Program, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Aaron Fountain
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Sami Mamand
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada
- Polytechnic Research Center, Erbil Polytechnic University, Erbil, Kurdistan, Iraq
| | - Roberto J. Botelho
- Department of Chemistry and Biology, Toronto Metropolitan University, Toronto, Ontario, Canada
- Graduate Program in Molecular Science, Toronto Metropolitan University, Toronto, Ontario, Canada
| | - Peter K. Kim
- Cell Biology Program, Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, South Korea
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9
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Weesner JA, Annunziata I, van de Vlekkert D, d'Azzo A. Glycosphingolipids within membrane contact sites influence their function as signaling hubs in neurodegenerative diseases. FEBS Open Bio 2023; 13:1587-1600. [PMID: 37014126 PMCID: PMC10476575 DOI: 10.1002/2211-5463.13605] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/24/2023] [Accepted: 04/03/2023] [Indexed: 04/05/2023] Open
Abstract
Intracellular organelles carry out many of their functions by engaging in extensive interorganellar communication through specialized membrane contact sites (MCSs) formed where two organelles tether to each other or to the plasma membrane (PM) without fusing. In recent years, these ubiquitous membrane structures have emerged as central signaling hubs that control a multitude of cellular pathways, ranging from lipid metabolism/transport to the exchange of metabolites and ions (i.e., Ca2+ ), and general organellar biogenesis. The functional crosstalk between juxtaposed membranes at MCSs relies on a defined composite of proteins and lipids that populate these microdomains in a dynamic fashion. This is particularly important in the nervous system, where alterations in the composition of MCSs have been shown to affect their functions and have been implicated in the pathogenesis of neurodegenerative diseases. In this review, we focus on the MCSs that are formed by the tethering of the endoplasmic reticulum (ER) to the mitochondria, the ER to the endo-lysosomes and the mitochondria to the lysosomes. We highlight how glycosphingolipids that are aberrantly processed/degraded and accumulate ectopically in intracellular membranes and the PM change the topology of MCSs, disrupting signaling pathways that lead to neuronal demise and neurodegeneration. In particular, we focus on neurodegenerative lysosomal storage diseases linked to altered glycosphingolipid catabolism.
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Affiliation(s)
| | - Ida Annunziata
- Department of GeneticsSt. Jude Children's Research HospitalMemphisTNUSA
- Compliance OfficeSt. Jude Children's Research HospitalMemphisTNUSA
| | | | - Alessandra d'Azzo
- Department of GeneticsSt. Jude Children's Research HospitalMemphisTNUSA
- Department of Anatomy and Neurobiology, College of Graduate Health SciencesUniversity of Tennessee Health Science CenterMemphisTNUSA
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10
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Henne WM. The (social) lives, deaths, and biophysical phases of lipid droplets. Curr Opin Cell Biol 2023; 82:102178. [PMID: 37295067 PMCID: PMC10782554 DOI: 10.1016/j.ceb.2023.102178] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/12/2023]
Abstract
Lipid droplets (LDs) are major lipid storage organelles, sequestering energy-rich triglycerides and serving as nutrient sinks for cellular homeostasis. Observed for over a century but generally ignored, LDs are now appreciated to play key roles in organismal physiology and disease. They also form numerous functional contacts with other organelles. Here, we highlight recent studies examining LDs from distinct perspectives of their life cycle: their biogenesis, "social" life as they interact with other organelles, and deaths via lipolysis or lipophagy. We also discuss recent work showing how changes in LD lipid content alter the biophysical phases of LD lipids, and how this may fine-tune the LD protein landscape and ultimately LD function.
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Affiliation(s)
- W Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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11
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Guillén-Samander A, De Camilli P. Endoplasmic Reticulum Membrane Contact Sites, Lipid Transport, and Neurodegeneration. Cold Spring Harb Perspect Biol 2023; 15:a041257. [PMID: 36123033 PMCID: PMC10071438 DOI: 10.1101/cshperspect.a041257] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Endoplasmic Reticulum (ER) is an endomembrane system that plays a multiplicity of roles in cell physiology and populates even the most distal cell compartments, including dendritic tips and axon terminals of neurons. Some of its functions are achieved by a cross talk with other intracellular membranous organelles and with the plasma membrane at membrane contacts sites (MCSs). As the ER synthesizes most membrane lipids, lipid exchanges mediated by lipid transfer proteins at MCSs are a particularly important aspect of this cross talk, which synergizes with the cross talk mediated by vesicular transport. Several mutations of genes that encode proteins localized at ER MCSs result in familial neurodegenerative diseases, emphasizing the importance of the normal lipid traffic within cells for a healthy brain. Here, we provide an overview of such diseases, with a specific focus on proteins that directly or indirectly impact lipid transport.
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Affiliation(s)
- Andrés Guillén-Samander
- Departments of Neuroscience and of Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06520, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland 20815, USA
| | - Pietro De Camilli
- Departments of Neuroscience and of Cell Biology, Howard Hughes Medical Institute, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06520, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland 20815, USA
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12
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Perini F, Cendron F, Wu Z, Sevane N, Li Z, Huang C, Smith J, Lasagna E, Cassandro M, Penasa M. Genomics of Dwarfism in Italian Local Chicken Breeds. Genes (Basel) 2023; 14:genes14030633. [PMID: 36980905 PMCID: PMC10047989 DOI: 10.3390/genes14030633] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023] Open
Abstract
The identification of the dwarf phenotype in chicken is based on body weight, height, and shank length, leaving the differentiation between dwarf and small breeds ambiguous. The aims of the present study were to characterize the sequence variations associated with the dwarf phenotype in three Italian chicken breeds and to investigate the genes associated with their phenotype. Five hundred and forty-one chickens from 23 local breeds (from 20 to 24 animals per breed) were sampled. All animals were genotyped with the 600 K chicken SNP array. Three breeds were described as “dwarf”, namely, Mericanel della Brianza (MERI), Mugellese (MUG), and Pepoi (PPP). We compared MERI, MUG, and PPP with the four heaviest breeds in the dataset by performing genome-wide association studies. Results showed significant SNPs associated with dwarfism in the MERI and MUG breeds, which shared a candidate genomic region on chromosome 1. Due to this similarity, MERI and MUG were analyzed together as a meta-population, observing significant SNPs in the LEMD3 and HMGA2 genes, which were previously reported as being responsible for dwarfism in different species. In conclusion, MERI and MUG breeds seem to share a genetic basis of dwarfism, which differentiates them from the small PPP breed.
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Affiliation(s)
- Francesco Perini
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06121 Perugia, Italy
| | - Filippo Cendron
- Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, 35020 Legnaro, Italy
| | - Zhou Wu
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Natalia Sevane
- Department of Animal Production, Veterinary Faculty, Universidad Complutense de Madrid, Avenida Puerta de Hierro, 28040 Madrid, Spain
| | - Zhiqiang Li
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06121 Perugia, Italy
- College of Animal Science and Technology, Chengdu Campus, Sichuan Agricultural University, Chengdu 611130, China
| | - Chunhua Huang
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06121 Perugia, Italy
- College of Animal Science and Technology, Chengdu Campus, Sichuan Agricultural University, Chengdu 611130, China
| | - Jacqueline Smith
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Emiliano Lasagna
- Department of Agricultural, Food and Environmental Sciences, University of Perugia, 06121 Perugia, Italy
- Correspondence: ; Tel.: +39-075-58517102
| | - Martino Cassandro
- Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, 35020 Legnaro, Italy
- Federazione delle Associazioni Nazionali di Razza e Specie, 00187 Roma, Italy
| | - Mauro Penasa
- Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, 35020 Legnaro, Italy
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13
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Da Graça J, Charles J, Djebar M, Alvarez-Valadez K, Botti J, Morel E. A SNX1-SNX2-VAPB partnership regulates endosomal membrane rewiring in response to nutritional stress. Life Sci Alliance 2023; 6:6/3/e202201652. [PMID: 36585258 PMCID: PMC9806675 DOI: 10.26508/lsa.202201652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 12/18/2022] [Accepted: 12/19/2022] [Indexed: 12/31/2022] Open
Abstract
Nutrient deprivation ("starvation") is a major catabolic stress faced by mammalian cells in both pathological and physiological situations. Starvation induces autophagosome biogenesis in the immediate vicinity of ER and leads to lysosome spatial repositioning, but little is known about the consequences of nutritional stress on endosomes. Here, we report that starvation induces tethering of endosomal tubules to ER subregions, fostering autophagosome assembly. We show that this endosomal membrane generation is regulated by sorting nexin 1 (SNX1) protein and is important for the autophagic response. These newly formed SNX1 endosomal tubules establish connections with ER subdomains engaged in early autophagic machinery mobilization. Such endosome-ER transient tethers are regulated by a local dialog between SNX2, an endosomal partner of SNX1, and VAPB, an ER protein associated with autophagy initiation stage regulation. We propose that in a very early response to starvation, SNX1 and SNX2 cooperation induces and regulates endosomal membrane tubulation towards VAPB-positive ER subdomains involved in autophagosome biogenesis, highlighting the contribution of early endosomes in the cellular response to nutritional stress.
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Affiliation(s)
- Juliane Da Graça
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Juliette Charles
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Morgane Djebar
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Karla Alvarez-Valadez
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Joëlle Botti
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Etienne Morel
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
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14
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Huang J, Tiu AC, Jose PA, Yang J. Sorting nexins: role in the regulation of blood pressure. FEBS J 2023; 290:600-619. [PMID: 34847291 PMCID: PMC9149145 DOI: 10.1111/febs.16305] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 10/13/2021] [Accepted: 11/29/2021] [Indexed: 02/06/2023]
Abstract
Sorting nexins (SNXs) are a family of proteins that regulate cellular cargo sorting and trafficking, maintain intracellular protein homeostasis, and participate in intracellular signaling. SNXs are also important in the regulation of blood pressure via several mechanisms. Aberrant expression and dysfunction of SNXs participate in the dysregulation of blood pressure. Genetic studies show a correlation between SNX gene variants and the response to antihypertensive drugs. In this review, we summarize the progress in SNX-mediated regulation of blood pressure, discuss the potential role of SNXs in the pathophysiology and treatment of hypertension, and propose novel strategies for the medical therapy of hypertension.
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Affiliation(s)
- Juan Huang
- Department of Clinical Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 410020, P.R. China
| | - Andrew C. Tiu
- Department of Medicine, Einstein Medical Center Philadelphia, Philadelphia, PA 19141, USA
| | - Pedro A. Jose
- Division of Renal Diseases & Hypertension, Department of Medicine, and Department of Physiology and Pharmacology, The George Washington University School of Medicine & Health Sciences, Washington, DC 20052, USA
| | - Jian Yang
- Department of Clinical Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 410020, P.R. China
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15
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Da Graça J, Morel E. Canonical and Non-Canonical Roles of SNX1 and SNX2 in Endosomal Membrane Dynamics. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2023; 6:25152564231217867. [PMID: 38033809 PMCID: PMC10683387 DOI: 10.1177/25152564231217867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 11/07/2023] [Accepted: 11/15/2023] [Indexed: 12/02/2023]
Abstract
Sorting nexins (SNXs) are a family of membrane-binding proteins known to play a critical role in regulating endocytic pathway sorting and endosomal membrane trafficking. Among them, SNX1 and SNX2 are members of the SNX-BAR subfamily and possess a membrane-curvature domain and a phosphoinositide-binding domain, which enables their stabilization at the phosphatidylinositol-3-phosphate (PI3P)-positive surface of endosomes. While their binding to PI3P-positive platforms facilitates interaction with endosomal partners and stabilization at the endosomal membrane, their SNX-BAR region is pivotal for generating membrane tubulation from endosomal compartments. In this context, their primary identified biological roles-and their partnership-are tightly associated with the retromer and endosomal SNX-BAR sorting complex for promoting exit 1 complex trafficking, facilitating the transport of cargoes from early endosomes to the secretory pathway. However, recent literature indicates that these proteins also possess biological functions in other aspects of endosomal features and sorting processes. Notably, SNX2 has been found to regulate endosome-endoplasmic reticulum (ER) contact sites through its interaction with VAP proteins at the ER membrane. Furthermore, data from our laboratory show that SNX1 and SNX2 are involved in the tubulation of early endosomes toward ER sites associated with autophagy initiation during starvation. These findings shed light on a novel role of SNXs in inter-organelle tethering and communication. In this concise review, we will explore the non-retromer functions of SNX1 and SNX2, specifically focusing on their involvement in endosomal membrane dynamics during stress sensing and autophagy-associated processes.
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Affiliation(s)
- Juliane Da Graça
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
| | - Etienne Morel
- Université Paris Cité, INSERM UMR-S1151, CNRS UMR-S8253, Institut Necker Enfants Malades, Paris, France
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16
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Overduin M, Tran A, Eekels DM, Overduin F, Kervin TA. Transmembrane Membrane Readers form a Novel Class of Proteins That Include Peripheral Phosphoinositide Recognition Domains and Viral Spikes. MEMBRANES 2022; 12:1161. [PMID: 36422153 PMCID: PMC9692390 DOI: 10.3390/membranes12111161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 06/16/2023]
Abstract
Membrane proteins are broadly classified as transmembrane (TM) or peripheral, with functions that pertain to only a single bilayer at a given time. Here, we explicate a class of proteins that contain both transmembrane and peripheral domains, which we dub transmembrane membrane readers (TMMRs). Their transmembrane and peripheral elements anchor them to one bilayer and reversibly attach them to another section of bilayer, respectively, positioning them to tether and fuse membranes while recognizing signals such as phosphoinositides (PIs) and modifying lipid chemistries in proximity to their transmembrane domains. Here, we analyze full-length models from AlphaFold2 and Rosetta, as well as structures from nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography, using the Membrane Optimal Docking Area (MODA) program to map their membrane-binding surfaces. Eukaryotic TMMRs include phospholipid-binding C1, C2, CRAL-TRIO, FYVE, GRAM, GTPase, MATH, PDZ, PH, PX, SMP, StART and WD domains within proteins including protrudin, sorting nexins and synaptotagmins. The spike proteins of SARS-CoV-2 as well as other viruses are also TMMRs, seeing as they are anchored into the viral membrane while mediating fusion with host cell membranes. As such, TMMRs have key roles in cell biology and membrane trafficking, and include drug targets for diseases such as COVID-19.
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Affiliation(s)
- Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Anh Tran
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | | | - Finn Overduin
- Institute of Nutritional Science, University of Potsdam, 14476 Potsdam, Germany
| | - Troy A. Kervin
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
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17
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Trachsel T, Prader S, Steindl K, Pachlopnik Schmid J. Case report: ETS1 gene deletion associated with a low number of recent thymic emigrants in three patients with Jacobsen syndrome. Front Immunol 2022; 13:867206. [PMID: 36341443 PMCID: PMC9634179 DOI: 10.3389/fimmu.2022.867206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 10/10/2022] [Indexed: 11/30/2022] Open
Abstract
Jacobsen syndrome is a rare genetic disorder associated with a terminal deletion in chromosome 11. The clinical presentation is variable. Although immunodeficiency has been described in patients with Jacobsen syndrome, a clear genotype-phenotype correlation has not yet been established. Here, we report on the immunologic phenotypes of four patients with Jacobsen syndrome. All four patients showed one or more atypical immunologic features. One patient suffered from recurrent viral infections, two patients had experienced a severe bacterial infection and one had received antibiotic prophylaxis since early childhood. One patient had experienced severe, transient immune dysregulation. Hypogammaglobulinemia and low B cell counts were found in two patients, while the number of recent thymic emigrants (CD31+CD45RA+ CD4 cells) was abnormally low in three. When considering the six immune-related genes located within the affected part of chromosome 11 (ETS1, TIRAP, FLI1, NFRKB, THYN1, and SNX19), only the ETS1 gene was found be deleted in the three patients with low numbers of recent thymic emigrants and non-switched memory B cells. Our findings support the hypothesis whereby Jacobsen syndrome is associated with a combined immunodeficiency with variable presentation. Further investigations of potential genotype-phenotype correlations are warranted and might help to personalize patient management in individuals lacking immune-related genes. In addition, we recommend immunologic follow-up for all patients with Jacobsen syndrome, as immune abnormalities may develop over time.
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Affiliation(s)
- Tina Trachsel
- Division of Immunology, University Children’s Hospital Zurich, Zurich, Switzerland
| | - Seraina Prader
- Division of Immunology, University Children’s Hospital Zurich, Zurich, Switzerland
| | - Katharina Steindl
- Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
| | - Jana Pachlopnik Schmid
- Division of Immunology, University Children’s Hospital Zurich, Zurich, Switzerland
- Pediatric Immunology, University of Zurich, Zurich, Switzerland
- *Correspondence: Jana Pachlopnik Schmid,
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18
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Scerra G, De Pasquale V, Scarcella M, Caporaso MG, Pavone LM, D'Agostino M. Lysosomal positioning diseases: beyond substrate storage. Open Biol 2022; 12:220155. [PMID: 36285443 PMCID: PMC9597170 DOI: 10.1098/rsob.220155] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Lysosomal storage diseases (LSDs) comprise a group of inherited monogenic disorders characterized by lysosomal dysfunctions due to undegraded substrate accumulation. They are caused by a deficiency in specific lysosomal hydrolases involved in cellular catabolism, or non-enzymatic proteins essential for normal lysosomal functions. In LSDs, the lack of degradation of the accumulated substrate and its lysosomal storage impairs lysosome functions resulting in the perturbation of cellular homeostasis and, in turn, the damage of multiple organ systems. A substantial number of studies on the pathogenesis of LSDs has highlighted how the accumulation of lysosomal substrates is only the first event of a cascade of processes including the accumulation of secondary metabolites and the impairment of cellular trafficking, cell signalling, autophagic flux, mitochondria functionality and calcium homeostasis, that significantly contribute to the onset and progression of these diseases. Emerging studies on lysosomal biology have described the fundamental roles of these organelles in a variety of physiological functions and pathological conditions beyond their canonical activity in cellular waste clearance. Here, we discuss recent advances in the knowledge of cellular and molecular mechanisms linking lysosomal positioning and trafficking to LSDs.
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Affiliation(s)
- Gianluca Scerra
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Valeria De Pasquale
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Via Federico Delpino 1, 80137 Naples, Italy
| | - Melania Scarcella
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Maria Gabriella Caporaso
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Luigi Michele Pavone
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Massimo D'Agostino
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
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19
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Lu A. Endolysosomal cholesterol export: More than just NPC1. Bioessays 2022; 44:e2200111. [PMID: 35934896 DOI: 10.1002/bies.202200111] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/22/2022] [Accepted: 07/26/2022] [Indexed: 11/07/2022]
Abstract
NPC1 plays a central role in cholesterol egress from endolysosomes, a critical step for maintaining intracellular cholesterol homeostasis. Despite recent advances in the field, the full repertoire of molecules and pathways involved in this process remains unknown. Emerging evidence suggests the existence of NPC1-independent, alternative routes. These may involve vesicular and non-vesicular mechanisms, as well as release of extracellular vesicles. Understanding the underlying molecular mechanisms that bypass NPC1 function could have important implications for the development of therapies for lysosomal storage disorders. Here we discuss how cholesterol may be exported from lysosomes in which NPC1 function is impaired.
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Affiliation(s)
- Albert Lu
- Departament de Biomedicina, Unitat de Biologia Cellular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Barcelona, Spain
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20
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Yap CC, Winckler B. Spatial regulation of endosomes in growing dendrites. Dev Biol 2022; 486:5-14. [PMID: 35306006 PMCID: PMC10646839 DOI: 10.1016/j.ydbio.2022.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/21/2022] [Accepted: 03/13/2022] [Indexed: 01/19/2023]
Abstract
Many membrane proteins are highly enriched in either dendrites or axons. This non-uniform distribution is a critical feature of neuronal polarity and underlies neuronal function. The molecular mechanisms responsible for polarized distribution of membrane proteins has been studied for some time and many answers have emerged. A less well studied feature of neurons is that organelles are also frequently non-uniformly distributed. For instance, EEA1-positive early endosomes are somatodendritic whereas synaptic vesicles are axonal. In addition, some organelles are present in both axons and dendrites, but not distributed uniformly along the processes. One well known example are lysosomes which are abundant in the soma and proximal dendrite, but sparse in the distal dendrite and the distal axon. The mechanisms that determine the spatial distribution of organelles along dendrites are only starting to be studied. In this review, we will discuss the cell biological mechanisms of how the distribution of diverse sets of endosomes along the proximal-distal axis of dendrites might be regulated. In particular, we will focus on the regulation of bulk homeostatic mechanisms as opposed to local regulation. We posit that immature dendrites regulate organelle motility differently from mature dendrites in order to spatially organize dendrite growth, branching and sculpting.
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21
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Keren-Kaplan T, Sarić A, Ghosh S, Williamson CD, Jia R, Li Y, Bonifacino JS. RUFY3 and RUFY4 are ARL8 effectors that promote coupling of endolysosomes to dynein-dynactin. Nat Commun 2022; 13:1506. [PMID: 35314674 PMCID: PMC8938451 DOI: 10.1038/s41467-022-28952-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 02/18/2022] [Indexed: 11/10/2022] Open
Abstract
The small GTPase ARL8 associates with endolysosomes, leading to the recruitment of several effectors that couple endolysosomes to kinesins for anterograde transport along microtubules, and to tethering factors for eventual fusion with other organelles. Herein we report the identification of the RUN- and FYVE-domain-containing proteins RUFY3 and RUFY4 as ARL8 effectors that promote coupling of endolysosomes to dynein-dynactin for retrograde transport along microtubules. Using various methodologies, we find that RUFY3 and RUFY4 interact with both GTP-bound ARL8 and dynein-dynactin. In addition, we show that RUFY3 and RUFY4 promote concentration of endolysosomes in the juxtanuclear area of non-neuronal cells, and drive redistribution of endolysosomes from the axon to the soma in hippocampal neurons. The function of RUFY3 in retrograde transport contributes to the juxtanuclear redistribution of endolysosomes upon cytosol alkalinization. These studies thus identify RUFY3 and RUFY4 as ARL8-dependent, dynein-dynactin adaptors or regulators, and highlight the role of ARL8 in the control of both anterograde and retrograde endolysosome transport. Organellar transport is carefully regulated, and endolysosome localized ARL8 is important for kinesin recruitment and anterograde movement. Here, the authors show that RUFY3 and RUFY4 promote retrograde transport of endolysosomes by mediating interaction of ARL8 with dynein-dynactin.
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22
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Lauzier A, Bossanyi MF, Larcher R, Nassari S, Ugrankar R, Henne WM, Jean S. Snazarus and its human ortholog SNX25 modulate autophagic flux. J Cell Sci 2022; 135:273525. [PMID: 34821359 DOI: 10.1242/jcs.258733] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 11/12/2021] [Indexed: 12/26/2022] Open
Abstract
Macroautophagy, the degradation and recycling of cytosolic components in the lysosome, is an important cellular mechanism. It is a membrane-mediated process that is linked to vesicular trafficking events. The sorting nexin (SNX) protein family controls the sorting of a large array of cargoes, and various SNXs impact autophagy. To improve our understanding of their functions in vivo, we screened all Drosophila SNXs using inducible RNA interference in the fat body. Significantly, depletion of Snazarus (Snz) led to decreased autophagic flux. Interestingly, we observed altered distribution of Vamp7-positive vesicles with Snz depletion, and the roles of Snz were conserved in human cells. SNX25, the closest human ortholog to Snz, regulates both VAMP8 endocytosis and lipid metabolism. Through knockout-rescue experiments, we demonstrate that these activities are dependent on specific SNX25 domains and that the autophagic defects seen upon SNX25 loss can be rescued by ethanolamine addition. We also demonstrate the presence of differentially spliced forms of SNX14 and SNX25 in cancer cells. This work identifies a conserved role for Snz/SNX25 as a regulator of autophagic flux and reveals differential isoform expression between paralogs.
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Affiliation(s)
- Annie Lauzier
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Marie-France Bossanyi
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Raphaëlle Larcher
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Sonya Nassari
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
| | - Rupali Ugrankar
- Department of Cell Biology, UT Southwestern Medical Center, 6000 Hary Lines Boulevard, Dallas, TX 75390, USA
| | - W Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, 6000 Hary Lines Boulevard, Dallas, TX 75390, USA
| | - Steve Jean
- Faculté de Médecine et des Sciences de la Santé, Département d'immunologie et de biologie cellulaire, Université de Sherbrooke, 3201, Rue Jean Mignault, Sherbrooke, Québec, CanadaJ1E 4K8
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23
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Lu A, Hsieh F, Sharma BR, Vaughn SR, Enrich C, Pfeffer SR. CRISPR screens for lipid regulators reveal a role for ER-bound SNX13 in lysosomal cholesterol export. J Cell Biol 2022; 221:212937. [PMID: 34936700 PMCID: PMC8704955 DOI: 10.1083/jcb.202105060] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 11/02/2021] [Accepted: 11/29/2021] [Indexed: 11/22/2022] Open
Abstract
We report here two genome-wide CRISPR screens performed to identify genes that, when knocked out, alter levels of lysosomal cholesterol or bis(monoacylglycero)phosphate. In addition, these screens were also performed under conditions of NPC1 inhibition to identify modifiers of NPC1 function in lysosomal cholesterol export. The screens confirm tight coregulation of cholesterol and bis(monoacylglycero)phosphate in cells and reveal an unexpected role for the ER-localized SNX13 protein as a negative regulator of lysosomal cholesterol export and contributor to ER–lysosome membrane contact sites. In the absence of NPC1 function, SNX13 knockdown redistributes lysosomal cholesterol and is accompanied by triacylglycerol-rich lipid droplet accumulation and increased lysosomal bis(monoacylglycero)phosphate. These experiments provide unexpected insight into the regulation of lysosomal lipids and modification of these processes by novel gene products.
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Affiliation(s)
- Albert Lu
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA.,Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Barcelona, Spain
| | | | - Bikal R Sharma
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA
| | - Sydney R Vaughn
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA
| | - Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Barcelona, Spain
| | - Suzanne R Pfeffer
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA
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Paul B, Weeratunga S, Tillu VA, Hariri H, Henne WM, Collins BM. Structural Predictions of the SNX-RGS Proteins Suggest They Belong to a New Class of Lipid Transfer Proteins. Front Cell Dev Biol 2022; 10:826688. [PMID: 35223850 PMCID: PMC8864675 DOI: 10.3389/fcell.2022.826688] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/13/2022] [Indexed: 12/12/2022] Open
Abstract
Recent advances in protein structure prediction using machine learning such as AlphaFold2 and RosettaFold presage a revolution in structural biology. Genome-wide predictions of protein structures are providing unprecedented insights into their architecture and intradomain interactions, and applications have already progressed towards assessing protein complex formation. Here we present detailed analyses of the sorting nexin proteins that contain regulator of G-protein signalling domains (SNX-RGS proteins), providing a key example of the ability of AlphaFold2 to reveal novel structures with previously unsuspected biological functions. These large proteins are conserved in most eukaryotes and are known to associate with lipid droplets (LDs) and sites of LD-membrane contacts, with key roles in regulating lipid metabolism. They possess five domains, including an N-terminal transmembrane domain that anchors them to the endoplasmic reticulum, an RGS domain, a lipid interacting phox homology (PX) domain and two additional domains named the PXA and PXC domains of unknown structure and function. Here we report the crystal structure of the RGS domain of sorting nexin 25 (SNX25) and show that the AlphaFold2 prediction closely matches the experimental structure. Analysing the full-length SNX-RGS proteins across multiple homologues and species we find that the distant PXA and PXC domains in fact fold into a single unique structure that notably features a large and conserved hydrophobic pocket. The nature of this pocket strongly suggests a role in lipid or fatty acid binding, and we propose that these molecules represent a new class of conserved lipid transfer proteins.
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Affiliation(s)
- Blessy Paul
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Saroja Weeratunga
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Vikas A. Tillu
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
| | - Hanaa Hariri
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - W. Mike Henne
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Brett M. Collins
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, Australia
- *Correspondence: Brett M. Collins,
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25
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Enrich C, Lu A, Tebar F, Rentero C, Grewal T. Annexins Bridging the Gap: Novel Roles in Membrane Contact Site Formation. Front Cell Dev Biol 2022; 9:797949. [PMID: 35071237 PMCID: PMC8770259 DOI: 10.3389/fcell.2021.797949] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/16/2021] [Indexed: 01/16/2023] Open
Abstract
Membrane contact sites (MCS) are specialized small areas of close apposition between two different organelles that have led researchers to reconsider the dogma of intercellular communication via vesicular trafficking. The latter is now being challenged by the discovery of lipid and ion transfer across MCS connecting adjacent organelles. These findings gave rise to a new concept that implicates cell compartments not to function as individual and isolated entities, but as a dynamic and regulated ensemble facilitating the trafficking of lipids, including cholesterol, and ions. Hence, MCS are now envisaged as metabolic platforms, crucial for cellular homeostasis. In this context, well-known as well as novel proteins were ascribed functions such as tethers, transporters, and scaffolds in MCS, or transient MCS companions with yet unknown functions. Intriguingly, we and others uncovered metabolic alterations in cell-based disease models that perturbed MCS size and numbers between coupled organelles such as endolysosomes, the endoplasmic reticulum, mitochondria, or lipid droplets. On the other hand, overexpression or deficiency of certain proteins in this narrow 10-30 nm membrane contact zone can enable MCS formation to either rescue compromised MCS function, or in certain disease settings trigger undesired metabolite transport. In this "Mini Review" we summarize recent findings regarding a subset of annexins and discuss their multiple roles to regulate MCS dynamics and functioning. Their contribution to novel pathways related to MCS biology will provide new insights relevant for a number of human diseases and offer opportunities to design innovative treatments in the future.
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Affiliation(s)
- Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Albert Lu
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cel·lular, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Thomas Grewal
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
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Lu A. Sorting (Nexin-13) out Novel Insights into Endolysosomal Cholesterol Export. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2022; 5:25152564221114513. [PMID: 37366510 PMCID: PMC10243570 DOI: 10.1177/25152564221114513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/28/2022] [Accepted: 07/21/2022] [Indexed: 06/28/2023]
Abstract
Transport in and out of the endolysosomal compartment represents a key step in the regulation of cellular cholesterol homeostasis. Despite important recent advances, how LDL-derived, free cholesterol is exported from the lumen of endolysosomes to other organelles is still a matter of debate. We recently devised a CRISPR/Cas9 genome-scale strategy to uncover genes involved in the regulation of endolysosomal cholesterol homeostasis and the functionally linked phospholipid, bis(monoacylglycerol)-phosphate. This approach confirmed known genes and pathways involved in this process, and more importantly revealed previously unrecognized roles for new players, such as Sorting Nexin-13 (SNX13). Here we discuss the unexpected regulatory role of SNX13 in endolysosomal cholesterol export.
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Affiliation(s)
- Albert Lu
- Departament de Biomedicina, Unitat de Biologia Cel·lular,
Facultat de Medicina i Ciències de la Salut, Centre de Recerca Biomèdica CELLEX, Institut
d’Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Barcelona, Spain
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27
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Williamson CD, Guardia CM, De Pace R, Bonifacino JS, Saric A. Measurement of Lysosome Positioning by Shell Analysis and Line Scan. Methods Mol Biol 2022; 2473:285-306. [PMID: 35819772 PMCID: PMC11072972 DOI: 10.1007/978-1-0716-2209-4_19] [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] [Indexed: 06/15/2023]
Abstract
Lysosomes are membrane-bound organelles that degrade diverse biomolecules and regulate a multitude of other essential processes including cell growth and metabolism, signaling, plasma membrane repair and infection. Such diverse functions of lysosomes are highly coordinated in space and time and are therefore tightly coupled to the directional transport of the organelles within the cytoplasm. Thus, robust quantitative assessments of lysosome positioning within the cell provide a valuable tool for researchers interested in understanding these multifunctional organelles. Here, we present point-by-point methodology to measure lysosome positioning by two straight forward and widely used techniques: shell analysis and line scan.
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Affiliation(s)
- Chad D Williamson
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Carlos M Guardia
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Raffaella De Pace
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Amra Saric
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, ON, Canada.
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28
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Wagner K, Smylla TK, Lampe M, Krieg J, Huber A. Phospholipase D and retromer promote recycling of TRPL ion channel via the endoplasmic reticulum. Traffic 2021; 23:42-62. [PMID: 34719094 DOI: 10.1111/tra.12824] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 10/20/2021] [Accepted: 10/26/2021] [Indexed: 12/27/2022]
Abstract
Plasma membrane protein trafficking is of fundamental importance for cell function and cell integrity of neurons and includes regulated protein recycling. In this work, we report a novel role of the endoplasmic reticulum (ER) for protein recycling as discovered in trafficking studies of the ion channel TRPL in photoreceptor cells of Drosophila. TRPL is located within the rhabdomeric membrane from where it is endocytosed upon light stimulation and stored in the cell body. Conventional immunohistochemistry as well as stimulated emission depletion super-resolution microscopy revealed TRPL storage at the ER after illumination, suggesting an unusual recycling route of TRPL. Our results also imply that both phospholipase D (PLD) and retromer complex are required for correct recycling of TRPL to the rhabdomeric membrane. Loss of PLD activity in PLD3.1 mutants results in enhanced degradation of TRPL. In the retromer mutant vps35MH20 , TRPL is trapped in a Rab5-positive compartment. Evidenced by epistatic analysis in the double mutant PLD3.1 vps35MH20 , PLD activity precedes retromer function. We propose a model in which PLD and retromer function play key roles in the transport of TRPL to an ER enriched compartment.
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Affiliation(s)
- Krystina Wagner
- Department of Biochemistry, University of Hohenheim, Institute of Biology, Stuttgart, Germany
| | - Thomas K Smylla
- Department of Biochemistry, University of Hohenheim, Institute of Biology, Stuttgart, Germany
| | - Marko Lampe
- European Molecular Biology Laboratory, Advanced Light Microscopy Core Facility, Heidelberg, Germany
| | - Jana Krieg
- Department of Biochemistry, University of Hohenheim, Institute of Biology, Stuttgart, Germany
| | - Armin Huber
- Department of Biochemistry, University of Hohenheim, Institute of Biology, Stuttgart, Germany
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