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Li M, Du Y, Zhang X, Zhou W. Research advances of MAL family members in tumorigenesis and tumor progression (Review). Mol Med Rep 2024; 29:57. [PMID: 38362940 PMCID: PMC10884788 DOI: 10.3892/mmr.2024.13181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 01/05/2024] [Indexed: 02/17/2024] Open
Abstract
The myelin and lymphocyte protein (MAL) family is a novel gene family first identified and characterized in 2002. This family is comprised of seven members, including MAL, MAL2, plasmolipin, MALL, myeloid differentiation‑associated marker (MYADM), MYADML2 and CMTM8, which are located on different chromosomes. In addition to exhibiting extensive activity during transcytosis, the MAL family plays a vital role in the neurological, digestive, respiratory, genitourinary and other physiological systems. Furthermore, the intimate association between MAL and the pathogenesis, progression and metastasis of malignancies, attributable to several mechanisms such as DNA methylation has also been elucidated. In the present review, an overview of the structural and functional properties of the MAL family and the latest research findings regarding the relationship between several MAL members and various cancers is provided. Furthermore, the potential clinical and scientific significance of MAL is discussed and directions for future research are summarized.
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Affiliation(s)
- Mengyao Li
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Yan Du
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Xianzhuo Zhang
- The First School of Clinical Medicine, Lanzhou University, Lanzhou, Gansu 730000, P.R. China
| | - Wence Zhou
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu 730000, P.R. China
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Shetty SV, Mazzucco MR, Winokur P, Haigh SV, Rumah KR, Fischetti VA, Vartanian T, Linden JR. Clostridium perfringens Epsilon Toxin Binds to and Kills Primary Human Lymphocytes. Toxins (Basel) 2023; 15:423. [PMID: 37505692 PMCID: PMC10467094 DOI: 10.3390/toxins15070423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/30/2023] [Accepted: 06/07/2023] [Indexed: 07/29/2023] Open
Abstract
Clostridium perfringens epsilon toxin (ETX) is the third most lethal bacterial toxin and has been suggested to be an environmental trigger of multiple sclerosis, an immune-mediated disease of the human central nervous system. However, ETX cytotoxicity on primary human cells has not been investigated. In this article, we demonstrate that ETX preferentially binds to and kills human lymphocytes expressing increased levels of the myelin and lymphocyte protein MAL. Using flow cytometry, ETX binding was determined to be time and dose dependent and was highest for CD4+ cells, followed by CD8+ and then CD19+ cells. Similar results were seen with ETX-induced cytotoxicity. To determine if ETX preference for CD4+ cells was related to MAL expression, MAL gene expression was determined by RT-qPCR. CD4+ cells had the highest amount of Mal gene expression followed by CD8+ and CD19+ cells. These data indicate that primary human cells are susceptible to ETX and support the hypothesis that MAL is a main receptor for ETX. Interestingly, ETX bindings to human lymphocytes suggest that ETX may influence immune response in multiple sclerosis.
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Affiliation(s)
- Samantha V. Shetty
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA (T.V.)
| | - Michael R. Mazzucco
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA (T.V.)
| | - Paige Winokur
- Harold and Margaret Milliken Hatch Laboratory of Neuro-Endocrinology Rockefeller University, New York, NY 10065, USA
| | - Sylvia V. Haigh
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA (T.V.)
| | - Kareem Rashid Rumah
- Laboratory of Bacterial Pathogenesis and Immunology, Rockefeller University, New York, NY 10065, USA
| | - Vincent A. Fischetti
- Laboratory of Bacterial Pathogenesis and Immunology, Rockefeller University, New York, NY 10065, USA
| | - Timothy Vartanian
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA (T.V.)
| | - Jennifer R. Linden
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA (T.V.)
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3
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Rubio-Ramos A, Bernabé-Rubio M, Labat-de-Hoz L, Casares-Arias J, Kremer L, Correas I, Alonso MA. MALL, a membrane-tetra-spanning proteolipid overexpressed in cancer, is present in membraneless nuclear biomolecular condensates. Cell Mol Life Sci 2022; 79:236. [PMID: 35399121 PMCID: PMC8995265 DOI: 10.1007/s00018-022-04270-w] [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: 12/15/2021] [Revised: 03/08/2022] [Accepted: 03/22/2022] [Indexed: 12/04/2022]
Abstract
Proteolipids are proteins with unusual lipid-like properties. It has long been established that PLP and plasmolipin, which are two unrelated membrane-tetra-spanning myelin proteolipids, can be converted in vitro into a water-soluble form with a distinct conformation, raising the question of whether these, or other similar proteolipids, can adopt two different conformations in the cell to adapt their structure to distinct environments. Here, we show that MALL, another proteolipid with a membrane-tetra-spanning structure, distributes in membranes outside the nucleus and, within the nucleus, in membrane-less, liquid-like PML body biomolecular condensates. Detection of MALL in one or other environment was strictly dependent on the method of cell fixation used, suggesting that MALL adopts different conformations depending on its physical environment —lipidic or aqueous— in the cell. The acquisition of the condensate-compatible conformation requires PML expression. Excess MALL perturbed the distribution of the inner nuclear membrane proteins emerin and LAP2β, and that of the DNA-binding protein BAF, leading to the formation of aberrant nuclei. This effect, which is consistent with studies identifying overexpressed MALL as an unfavorable prognostic factor in cancer, could contribute to cell malignancy. Our study establishes a link between proteolipids, membranes and biomolecular condensates, with potential biomedical implications.
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Affiliation(s)
- Armando Rubio-Ramos
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Miguel Bernabé-Rubio
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Leticia Labat-de-Hoz
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Javier Casares-Arias
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Leonor Kremer
- Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049, Madrid, Spain
| | - Isabel Correas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain
- Department of Molecular Biology, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | - Miguel A Alonso
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
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Dolinski AC, Homola JJ, Jankowski MD, Robinson JD, Owen JC. Differential gene expression reveals host factors for viral shedding variation in mallards ( Anas platyrhynchos) infected with low-pathogenic avian influenza virus. J Gen Virol 2022; 103:10.1099/jgv.0.001724. [PMID: 35353676 PMCID: PMC10519146 DOI: 10.1099/jgv.0.001724] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intraspecific variation in pathogen shedding impacts disease transmission dynamics; therefore, understanding the host factors associated with individual variation in pathogen shedding is key to controlling and preventing outbreaks. In this study, ileum and bursa of Fabricius tissues of wild-bred mallards (Anas platyrhynchos) infected with low-pathogenic avian influenza (LPAIV) were evaluated at various post-infection time points to determine genetic host factors associated with intraspecific variation in viral shedding. By analysing transcriptome sequencing data (RNA-seq), we found that LPAIV-infected wild-bred mallards do not exhibit differential gene expression compared to uninfected birds, but that gene expression was associated with cloacal viral shedding quantity early in the infection. In both tissues, immune gene expression was higher in high/moderate shedding birds compared to low shedding birds, and significant positive relationships with viral shedding were observed. In the ileum, expression for host genes involved in viral cell entry was lower in low shedders compared to moderate shedders at 1 day post-infection (DPI), and expression for host genes promoting viral replication was higher in high shedders compared to low shedders at 2 DPI. Our findings indicate that viral shedding is a key factor for gene expression differences in LPAIV-infected wild-bred mallards, and the genes identified in this study could be important for understanding the molecular mechanisms driving intraspecific variation in pathogen shedding.
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Affiliation(s)
- Amanda C. Dolinski
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Jared J. Homola
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Mark D. Jankowski
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
- U.S. Environmental Protection Agency, Region 10, Seattle,
WA 98101
| | - John D. Robinson
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
| | - Jennifer C. Owen
- Department of Fisheries and Wildlife, Michigan State
University, East Lansing, MI
- Department of Large Animal Clinical Sciences, Michigan
State University, East Lansing, MI, USA
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Geng Z, Li J, Li S, Wang Y, Zhang L, Hu Q, Wang X, Zuo L, Song X, Zhang X, Ge S, Hu J. MAL protein suppresses the metastasis and invasion of GC cells by interfering with the phosphorylation of STAT3. J Transl Med 2022; 20:50. [PMID: 35093120 PMCID: PMC8800308 DOI: 10.1186/s12967-022-03254-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 01/16/2022] [Indexed: 11/10/2022] Open
Abstract
AbstractGastric cancer (GC) is the fifth leading cause of cancer-related death worldwide and is accompanied by low diagnosis and survival rates. The molecular mechanism of GC must be elucidated to improve treatment strategies. Recent research has shown that the expression of myelin and lymphocyte (MAL) protein is reduced in a variety of adenocarcinomas and has the function of suppressing tumor growth. However, the mechanism by which MAL regulates the epithelial-mesenchymal transition (EMT) in GC remains unclear. Here, we showed that MAL expression was downregulated in specimens from patients with GC and was negatively correlated with the clinical stage. Gain- and loss-of function assays showed that interference with MAL significantly increased tumor cell proliferation, metastasis, invasion and the EMT. Overexpression of MAL significantly inhibited the malignant behavior of GC cells. Moreover, MAL suppressed the malignant behavior of GC cells by inhibiting STAT3 phosphorylation in vitro and in vivo. Our data indicate that MAL suppresses the malignant behavior of GC cells via the STAT3/EMT axis. This study also provides insights into the pathophysiological process of GC and a reference for diagnosis and treatment.
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Rubio-Ramos A, Labat-de-Hoz L, Correas I, Alonso MA. The MAL Protein, an Integral Component of Specialized Membranes, in Normal Cells and Cancer. Cells 2021; 10:1065. [PMID: 33946345 PMCID: PMC8145151 DOI: 10.3390/cells10051065] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 12/12/2022] Open
Abstract
The MAL gene encodes a 17-kDa protein containing four putative transmembrane segments whose expression is restricted to human T cells, polarized epithelial cells and myelin-forming cells. The MAL protein has two unusual biochemical features. First, it has lipid-like properties that qualify it as a member of the group of proteolipid proteins. Second, it partitions selectively into detergent-insoluble membranes, which are known to be enriched in condensed cell membranes, consistent with MAL being distributed in highly ordered membranes in the cell. Since its original description more than thirty years ago, a large body of evidence has accumulated supporting a role of MAL in specialized membranes in all the cell types in which it is expressed. Here, we review the structure, expression and biochemical characteristics of MAL, and discuss the association of MAL with raft membranes and the function of MAL in polarized epithelial cells, T lymphocytes, and myelin-forming cells. The evidence that MAL is a putative receptor of the epsilon toxin of Clostridium perfringens, the expression of MAL in lymphomas, the hypermethylation of the MAL gene and subsequent loss of MAL expression in carcinomas are also presented. We propose a model of MAL as the organizer of specialized condensed membranes to make them functional, discuss the role of MAL as a tumor suppressor in carcinomas, consider its potential use as a cancer biomarker, and summarize the directions for future research.
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Affiliation(s)
- Armando Rubio-Ramos
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain; (A.R.-R.); (L.L.-d.-H.); (I.C.)
| | - Leticia Labat-de-Hoz
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain; (A.R.-R.); (L.L.-d.-H.); (I.C.)
| | - Isabel Correas
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain; (A.R.-R.); (L.L.-d.-H.); (I.C.)
- Department of Molecular Biology, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Miguel A. Alonso
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, 28049 Madrid, Spain; (A.R.-R.); (L.L.-d.-H.); (I.C.)
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7
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Labat-de-Hoz L, Rubio-Ramos A, Casares-Arias J, Bernabé-Rubio M, Correas I, Alonso MA. A Model for Primary Cilium Biogenesis by Polarized Epithelial Cells: Role of the Midbody Remnant and Associated Specialized Membranes. Front Cell Dev Biol 2021; 8:622918. [PMID: 33585461 PMCID: PMC7873843 DOI: 10.3389/fcell.2020.622918] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 12/09/2020] [Indexed: 12/14/2022] Open
Abstract
Primary cilia are solitary, microtubule-based protrusions surrounded by a ciliary membrane equipped with selected receptors that orchestrate important signaling pathways that control cell growth, differentiation, development and homeostasis. Depending on the cell type, primary cilium assembly takes place intracellularly or at the cell surface. The intracellular route has been the focus of research on primary cilium biogenesis, whereas the route that occurs at the cell surface, which we call the "alternative" route, has been much less thoroughly characterized. In this review, based on recent experimental evidence, we present a model of primary ciliogenesis by the alternative route in which the remnant of the midbody generated upon cytokinesis acquires compact membranes, that are involved in compartmentalization of biological membranes. The midbody remnant delivers part of those membranes to the centrosome in order to assemble the ciliary membrane, thereby licensing primary cilium formation. The midbody remnant's involvement in primary cilium formation, the regulation of its inheritance by the ESCRT machinery, and the assembly of the ciliary membrane from the membranes originally associated with the remnant are discussed in the context of the literature concerning the ciliary membrane, the emerging roles of the midbody remnant, the regulation of cytokinesis, and the role of membrane compartmentalization. We also present a model of cilium emergence during evolution, and summarize the directions for future research.
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Affiliation(s)
- Leticia Labat-de-Hoz
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Armando Rubio-Ramos
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Javier Casares-Arias
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Miguel Bernabé-Rubio
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Isabel Correas
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
- Department of Molecular Biology, Universidad Autónoma de Madrid, Madrid, Spain
| | - Miguel A. Alonso
- Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
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8
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Shulgin AA, Lebedev TD, Prassolov VS, Spirin PV. Plasmolipin and Its Role in Cell Processes. Mol Biol 2021; 55:773-785. [PMID: 34955555 PMCID: PMC8682038 DOI: 10.1134/s0026893321050113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/26/2021] [Accepted: 04/05/2021] [Indexed: 12/04/2022]
Abstract
The mechanisms involved in the origin and development of malignant and neurodegenerative diseases are an important area of modern biomedicine. A crucial task is to identify new molecular markers that are associated with rearrangements of intracellular signaling and can be used for prognosis and the development of effective treatment approaches. The proteolipid plasmolipin (PLLP) is a possible marker. PLLP is a main component of the myelin sheath and plays an important role in the development and normal function of the nervous system. PLLP is involved in intracellular transport, lipid raft formation, and Notch signaling. PLLP is presumably involved in various disorders, such as cancer, schizophrenia, Alzheimer's disease, and type 2 diabetes mellitus. PLLP and its homologs were identified as possible virus entry receptors. The review summarizes the data on the PLLP structure, normal functions, and role in diseases.
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Affiliation(s)
- A. A. Shulgin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia ,Moscow Institute of Physics and Technology (State University), 141701 Dolgoprudny, Moscow oblast Russia
| | - T. D. Lebedev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - V. S. Prassolov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - P. V. Spirin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
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Labat-de-Hoz L, Alonso MA. The formin INF2 in disease: progress from 10 years of research. Cell Mol Life Sci 2020; 77:4581-4600. [PMID: 32451589 PMCID: PMC11104792 DOI: 10.1007/s00018-020-03550-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 05/04/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023]
Abstract
Formins are a conserved family of proteins that primarily act to form linear polymers of actin. Despite their importance to the normal functioning of the cytoskeleton, for a long time, the only two formin genes known to be a genetic cause of human disorders were DIAPH1 and DIAPH3, whose mutation causes two distinct forms of hereditary deafness. In the last 10 years, however, the formin INF2 has emerged as an important target of mutations responsible for the appearance of focal segmental glomerulosclerosis, which are histological lesions associated with glomerulus degeneration that often leads to end-stage renal disease. In some rare cases, focal segmental glomerulosclerosis concurs with Charcot-Marie-Tooth disease, which is a degenerative neurological disorder affecting peripheral nerves. All known INF2 gene mutations causing disease map to the exons encoding the amino-terminal domain. In this review, we summarize the structure, biochemical features and functions of INF2, conduct a systematic and comprehensive analysis of the pathogenic INF2 mutations, including a detailed study exon-by-exon of patient cases and mutations, address the impact of the pathogenic mutations on the structure, regulation and known functions of INF2, draw a series of conclusions that could be useful for INF2-related disease diagnosis, and suggest lines of research for future work on the molecular mechanisms by which INF2 causes disease.
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Affiliation(s)
- Leticia Labat-de-Hoz
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain
| | - Miguel A Alonso
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Madrid, Spain.
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Dalghi MG, Montalbetti N, Carattino MD, Apodaca G. The Urothelium: Life in a Liquid Environment. Physiol Rev 2020; 100:1621-1705. [PMID: 32191559 PMCID: PMC7717127 DOI: 10.1152/physrev.00041.2019] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/02/2020] [Accepted: 03/14/2020] [Indexed: 02/08/2023] Open
Abstract
The urothelium, which lines the renal pelvis, ureters, urinary bladder, and proximal urethra, forms a high-resistance but adaptable barrier that surveils its mechanochemical environment and communicates changes to underlying tissues including afferent nerve fibers and the smooth muscle. The goal of this review is to summarize new insights into urothelial biology and function that have occurred in the past decade. After familiarizing the reader with key aspects of urothelial histology, we describe new insights into urothelial development and regeneration. This is followed by an extended discussion of urothelial barrier function, including information about the roles of the glycocalyx, ion and water transport, tight junctions, and the cellular and tissue shape changes and other adaptations that accompany expansion and contraction of the lower urinary tract. We also explore evidence that the urothelium can alter the water and solute composition of urine during normal physiology and in response to overdistension. We complete the review by providing an overview of our current knowledge about the urothelial environment, discussing the sensor and transducer functions of the urothelium, exploring the role of circadian rhythms in urothelial gene expression, and describing novel research tools that are likely to further advance our understanding of urothelial biology.
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Affiliation(s)
- Marianela G Dalghi
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Nicolas Montalbetti
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Marcelo D Carattino
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Gerard Apodaca
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Van Campen H, Bishop JV, Abrahams VM, Bielefeldt-Ohmann H, Mathiason CK, Bouma GJ, Winger QA, Mayo CE, Bowen RA, Hansen TR. Maternal Influenza A Virus Infection Restricts Fetal and Placental Growth and Adversely Affects the Fetal Thymic Transcriptome. Viruses 2020; 12:v12091003. [PMID: 32911797 PMCID: PMC7551156 DOI: 10.3390/v12091003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 12/14/2022] Open
Abstract
Maternal influenza A viral infections in humans are associated with low birth weight, increased risk of pre-term birth, stillbirth and congenital defects. To examine the effect of maternal influenza virus infection on placental and fetal growth, pregnant C57BL/6 mice were inoculated intranasally with influenza A virus A/CA/07/2009 pandemic H1N1 or phosphate-buffered saline (PBS) at E3.5, E7.5 or E12.5, and the placentae and fetuses collected and weighed at E18.5. Fetal thymuses were pooled from each litter. Placentae were examined histologically, stained by immunohistochemistry (IHC) for CD34 (hematopoietic progenitor cell antigen) and vascular channels quantified. RNA from E7.5 and E12.5 placentae and E7.5 fetal thymuses was subjected to RNA sequencing and pathway analysis. Placental weights were decreased in litters inoculated with influenza at E3.5 and E7.5. Placentae from E7.5 and E12.5 inoculated litters exhibited decreased labyrinth development and the transmembrane protein 150A gene was upregulated in E7.5 placentae. Fetal weights were decreased in litters inoculated at E7.5 and E12.5 compared to controls. RNA sequencing of E7.5 thymuses indicated that 957 genes were downregulated ≥2-fold including Mal, which is associated with Toll-like receptor signaling and T cell differentiation. There were 28 upregulated genes. It is concluded that maternal influenza A virus infection impairs fetal thymic gene expression as well as restricting placental and fetal growth.
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Affiliation(s)
- Hana Van Campen
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (C.K.M.); (C.E.M.)
| | - Jeanette V. Bishop
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
| | - Vikki M. Abrahams
- Department of Obstetrics, Gynecology & Reproductive Sciences, Yale School of Medicine, Yale University, New Haven, CT 06510, USA;
| | - Helle Bielefeldt-Ohmann
- Australian Infectious Diseases Research Centre, The University of Queensland, St. Lucia, QLD 4072, Australia;
| | - Candace K. Mathiason
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (C.K.M.); (C.E.M.)
| | - Gerrit J. Bouma
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
| | - Quinton A. Winger
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
| | - Christie E. Mayo
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (C.K.M.); (C.E.M.)
| | - Richard A. Bowen
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (C.K.M.); (C.E.M.)
| | - Thomas R. Hansen
- Animal Reproduction and Biotechnology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA; (H.V.C.); (J.V.B.); (G.J.B.); (Q.A.W.); (R.A.B.)
- Correspondence:
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12
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Extracellular Vesicles in Viral Spread and Antiviral Response. Viruses 2020; 12:v12060623. [PMID: 32521696 PMCID: PMC7354624 DOI: 10.3390/v12060623] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/01/2020] [Accepted: 06/04/2020] [Indexed: 12/12/2022] Open
Abstract
Viral spread by both enveloped and non-enveloped viruses may be mediated by extracellular vesicles (EVs), including microvesicles (MVs) and exosomes. These secreted vesicles have been demonstrated to be an efficient mechanism that viruses can use to enter host cells, enhance spread or evade the host immune response. However, the complex interplay between viruses and EVs gives rise to antagonistic biological tasks—to benefit the viruses, enhancing infection and interfering with the immune system or to benefit the host, by mediating anti-viral responses. Exosomes from cells infected with herpes simplex type 1 (HSV-1) may transport viral and host transcripts, proteins and innate immune components. This virus may also use MVs to expand its tropism and evade the host immune response. This review aims to describe the current knowledge about EVs and their participation in viral infection, with a specific focus on the role of exosomes and MVs in herpesvirus infections, particularly that of HSV-1.
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Lázaro-Diéguez F, Müsch A. Low Rho activity in hepatocytes prevents apical from basolateral cargo separation during trans-Golgi network to surface transport. Traffic 2020; 21:364-374. [PMID: 32124512 PMCID: PMC7959587 DOI: 10.1111/tra.12725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 12/24/2022]
Abstract
Hepatocytes, the main epithelial cells of the liver, organize their polarized membrane domains differently from ductal epithelia. They also differ in their biosynthetic delivery of single-membrane-spanning and glycophosphatidylinositol-anchored proteins to the apical domain. While ductal epithelia target apical proteins to varying degrees from the trans-Golgi network (TGN) to the apical surface directly, hepatocytes target them first to the basolateral domain, from where they undergo basolateral-to-apical transcytosis. How TGN-to-surface transport differs in both scenarios is unknown. Here, we report that the basolateral detour of a hepatocyte apical protein is due, in part, to low RhoA activity at the TGN, which prevents its segregation from basolateral transport carriers. Activating Rho in hepatocytic cells, which switches their polarity from hepatocytic to ductal, also led to apical-basolateral cargo segregation at the TGN as is typical for ductal cells, affirming a central role for Rho-signaling in different aspects of the hepatocytic polarity phenotype. Nevertheless, Rho-induced cargo segregation was not sufficient to target the apical protein directly; thus, failure to recruit apical targeting machinery also contributes to its indirect itinerary.
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Affiliation(s)
- Francisco Lázaro-Diéguez
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
| | - Anne Müsch
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York
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Occludin protects secretory cells from ER stress by facilitating SNARE-dependent apical protein exocytosis. Proc Natl Acad Sci U S A 2020; 117:4758-4769. [PMID: 32051248 DOI: 10.1073/pnas.1909731117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Tight junctions (TJs) are fundamental features of both epithelium and endothelium and are indispensable for vertebrate organ formation and homeostasis. However, mice lacking Occludin (Ocln) develop relatively normally to term. Here we show that Ocln is essential for mammary gland physiology, as mutant mice fail to produce milk. Surprisingly, Ocln null mammary glands showed intact TJ function and normal epithelial morphogenesis, cell differentiation, and tissue polarity, suggesting that Ocln is not required for these processes. Using single-cell transcriptomics, we identified milk-producing cells (MPCs) and found they were progressively more prone to endoplasmic reticulum (ER) stress as protein production increased exponentially during late pregnancy and lactation. Importantly, Ocln loss in MPCs resulted in greatly heightened ER stress; this in turn led to increased apoptosis and acute shutdown of protein expression, ultimately leading to lactation failure in the mutant mice. We show that the increased ER stress was caused by a secretory failure of milk proteins in Ocln null cells. Consistent with an essential role in protein secretion, Occludin was seen to reside on secretory vesicles and to be bound to SNARE proteins. Taken together, our results demonstrate that Ocln protects MPCs from ER stress by facilitating SNARE-dependent protein secretion and raise the possibility that other TJ components may participate in functions similar to Ocln.
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15
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Herpes Simplex Virus 1 Spread in Oligodendrocytic Cells Is Highly Dependent on MAL Proteolipid. J Virol 2020; 94:JVI.01739-19. [PMID: 31748392 PMCID: PMC6997773 DOI: 10.1128/jvi.01739-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 11/12/2019] [Indexed: 12/31/2022] Open
Abstract
Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establish latent infections in neurons. HSV-1 may spread from infected to uninfected cells by two main routes: by cell-free virus or by cell-to-cell spread. In the first case, virions exit into the extracellular space and then infect another cell from the outside. In the second case, viral transmission occurs through cell-to-cell contacts via a mechanism that is still poorly understood. A third mode of spread, using extracellular vesicles, also exists. In this study, we demonstrate the important role for a myelin protein, myelin and lymphocyte protein (MAL), in the process of cell-to-cell viral spread in oligodendrocytes. We show that MAL is involved in trafficking of virions along cell processes and that MAL depletion produces a significant alteration in the viral cycle, which reduces cell-to cell spread of HSV-1. Myelin and lymphocyte protein (MAL) is a tetraspan integral membrane protein that resides in detergent-insoluble membrane fractions enriched in condensed membranes. MAL is expressed in oligodendrocytes, in Schwann cells, where it is essential for the stability of myelin, and at the apical membrane of epithelial cells, where it has a critical role in transport. In T lymphocytes, MAL is found at the immunological synapse and plays a crucial role in exosome secretion. However, no involvement of MAL in viral infections has been reported so far. Here, we show that herpes simplex virus 1 (HSV-1) virions travel in association with MAL-positive structures to reach the end of cellular processes, which contact uninfected oligodendrocytes. Importantly, the depletion of MAL led to a significant decrease in infection, with a drastic reduction in the number of lytic plaques in MAL-silenced cells. These results suggest a significant role for MAL in viral spread at cell contacts. The participation of MAL in the cell-to-cell spread of HSV-1 may shed light on the involvement of proteolipids in this process. IMPORTANCE Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establish latent infections in neurons. HSV-1 may spread from infected to uninfected cells by two main routes: by cell-free virus or by cell-to-cell spread. In the first case, virions exit into the extracellular space and then infect another cell from the outside. In the second case, viral transmission occurs through cell-to-cell contacts via a mechanism that is still poorly understood. A third mode of spread, using extracellular vesicles, also exists. In this study, we demonstrate the important role for a myelin protein, myelin and lymphocyte protein (MAL), in the process of cell-to-cell viral spread in oligodendrocytes. We show that MAL is involved in trafficking of virions along cell processes and that MAL depletion produces a significant alteration in the viral cycle, which reduces cell-to cell spread of HSV-1.
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16
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Linden JR, Flores C, Schmidt EF, Uzal FA, Michel AO, Valenzuela M, Dobrow S, Vartanian T. Clostridium perfringens epsilon toxin induces blood brain barrier permeability via caveolae-dependent transcytosis and requires expression of MAL. PLoS Pathog 2019; 15:e1008014. [PMID: 31703116 PMCID: PMC6867657 DOI: 10.1371/journal.ppat.1008014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 11/20/2019] [Accepted: 08/01/2019] [Indexed: 12/13/2022] Open
Abstract
Clostridium perfringens epsilon toxin (ETX) is responsible for causing the economically devastating disease, enterotoxaemia, in livestock. It is well accepted that ETX causes blood brain barrier (BBB) permeability, however the mechanisms involved in this process are not well understood. Using in vivo and in vitro methods, we determined that ETX causes BBB permeability in mice by increasing caveolae-dependent transcytosis in brain endothelial cells. When mice are intravenously injected with ETX, robust ETX binding is observed in the microvasculature of the central nervous system (CNS) with limited to no binding observed in the vasculature of peripheral organs, indicating that ETX specifically targets CNS endothelial cells. ETX binding to CNS microvasculature is dependent on MAL expression, as ETX binding to CNS microvasculature of MAL-deficient mice was not detected. ETX treatment also induces extravasation of molecular tracers including 376Da fluorescein salt, 60kDA serum albumin, 70kDa dextran, and 155kDA IgG. Importantly, ETX-induced BBB permeability requires expression of both MAL and caveolin-1, as mice deficient in MAL or caveolin-1 did not exhibit ETX-induced BBB permeability. Examination of primary murine brain endothelial cells revealed an increase in caveolae in ETX-treated cells, resulting in dynamin and lipid raft-dependent vacuolation without cell death. ETX-treatment also results in a rapid loss of EEA1 positive early endosomes and accumulation of large, RAB7-positive late endosomes and multivesicular bodies. Based on these results, we hypothesize that ETX binds to MAL on the apical surface of brain endothelial cells, causing recruitment of caveolin-1, triggering caveolae formation and internalization. Internalized caveolae fuse with early endosomes which traffic to late endosomes and multivesicular bodies. We believe that these multivesicular bodies fuse basally, releasing their contents into the brain parenchyma. Clostridium perfringens epsilon toxin (ETX) is an extremely lethal bacterial toxin known to cause a devastating disease in livestock animals and may be a possible cause of multiple sclerosis in humans. ETX is well known to cause disruption of the blood-brain barrier (BBB), a critical structure necessary for proper brain function. Deterioration of this barrier allows entry of toxic blood-borne material to enter the brain. Although ETX-induced BBB dysfunction is well accepted, how this happens is unknown. Here, we demonstrate that ETX causes BBB permeability by inducing formation of cell-surface invaginations called caveolae in endothelial cells, the cells that line blood vessels. Importantly, only endothelial cells from the brain and other central nervous system organs appear to be a target of ETX, as the toxin only binds to blood vessels in these organs and not blood vessels from other organs. These ETX-induced caveolae fuse with other caveolae and specialized intracellular vesicles called endosomes. We predict that these endosomes engulf blood-borne material during their internalization, allowing material to travel from the blood, through the cell, and into brain tissue. We also show that expression of the protein MAL and caveolin-1 is necessary for ETX-induced BBB permeability.
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Affiliation(s)
- Jennifer R. Linden
- The Brain and Mind Research Institute and the Department of Neurology, Weill Cornell Medical College, New York, New York, United States of America
| | - Claudia Flores
- The Brain and Mind Research Institute and the Department of Neurology, Weill Cornell Medical College, New York, New York, United States of America
| | - Eric F. Schmidt
- Laboratory of Molecular Biology, The Rockefeller University, New York, New York, United States of America
| | - Francisco A. Uzal
- California Animal Health & Food Safety Laboratory System, San Bernardino Branch, University of California, Davis, San Bernardino, California, United States of America
| | - Adam O. Michel
- Laboratory of Comparative Pathology, Center of Comparative Medicine and Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medicine, New York, New York, United States of America
| | - Marissa Valenzuela
- The Brain and Mind Research Institute and the Department of Neurology, Weill Cornell Medical College, New York, New York, United States of America
| | - Sebastian Dobrow
- The Brain and Mind Research Institute and the Department of Neurology, Weill Cornell Medical College, New York, New York, United States of America
| | - Timothy Vartanian
- The Brain and Mind Research Institute and the Department of Neurology, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail:
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17
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Saveanu L, Zucchetti AE, Evnouchidou I, Ardouin L, Hivroz C. Is there a place and role for endocyticTCRsignaling? Immunol Rev 2019; 291:57-74. [DOI: 10.1111/imr.12764] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 04/02/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Loredana Saveanu
- National French Institute of Health and Medical Research (INSERM) 1149 Center of Research on Inflammation Paris France
- National French Center of Scientific Research (CNRS) ERL8252 Paris France
- Laboratory of Inflamex Excellency Faculty of Medicine Xavier Bichat Site Paris France
- Paris Diderot UniversitySorbonne Paris Cité Paris France
| | - Andres E. Zucchetti
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
| | - Irini Evnouchidou
- National French Institute of Health and Medical Research (INSERM) 1149 Center of Research on Inflammation Paris France
- National French Center of Scientific Research (CNRS) ERL8252 Paris France
- Laboratory of Inflamex Excellency Faculty of Medicine Xavier Bichat Site Paris France
- Paris Diderot UniversitySorbonne Paris Cité Paris France
- Inovarion Paris France
| | - Laurence Ardouin
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
| | - Claire Hivroz
- Institut Curie PSL Research UniversityINSERMU932 “Integrative analysis of T cell activation” team Paris France
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18
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Lara-Lemus R. On The Role of Myelin and Lymphocyte Protein (MAL) In Cancer: A Puzzle With Two Faces. J Cancer 2019; 10:2312-2318. [PMID: 31258734 PMCID: PMC6584422 DOI: 10.7150/jca.30376] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 02/07/2019] [Indexed: 12/25/2022] Open
Abstract
Myelin and lymphocyte protein (MAL) is an integral membrane protein constituent of lipid rafts, and it is implicated in apical transport of proteins in polarized epithelial cells. However, beyond the involvement of MAL in apical sorting and as its function as a raft stabilizer, it is still not totally clear how MAL participates in cell proliferating processes. More controversial and interesting is the fact that MAL has been implicated in carcinogenesis in two opposite ways. First, this protein is overexpressed in ovarian cancer and some kinds of lymphomas where it seems to favor cancer progression. Conversely, it has been reported that downregulation of the MAL gene by promoter hypermethylation is a hallmark of several adenocarcinomas. So far, there is not enough experimental evidence to help us understand this phenomenon, and no MAL mutations or MAL isoforms have been associated with these opposite functions. This review provides an updated summary of the structure and functions of MAL, and we will discuss the possible mechanisms underlying its roles as a tumor suppressor and a tumor progression factor.
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Affiliation(s)
- Roberto Lara-Lemus
- Department of Research in Biochemistry, Instituto Nacional de Enfermedades Respiratorias “Ismael Cosío Villegas”. Mexico City, 14080. Mexico
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19
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Wang X, Fan J, Yu F, Cui F, Sun X, Zhong L, Yan D, Zhou C, Deng G, Wang B, Qi X, Wang S, Qu L, Deng B, Pan M, Chen J, Wang Y, Song G, Tang H, Zhou Z, Peng Z. Decreased MALL expression negatively impacts colorectal cancer patient survival. Oncotarget 2017; 7:22911-27. [PMID: 26992238 PMCID: PMC5008411 DOI: 10.18632/oncotarget.8094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 02/25/2016] [Indexed: 02/05/2023] Open
Abstract
The aim of the present study was to determine whether MALL expression is associated with colon cancer progression and patient survival. MALL mRNA expression was reduced in the tumor tissues of 70% of the colon cancer patients and 75% of the rectal cancer patients as compared to their normal tissues. MALL protein was also significantly reduced in the tumor tissues of colon cancer patients (P < 0.001). Increased LOH and methylation of MALL was observed in tumor tissues as compared to normal tissues. Reduced MALL expression was associated with vessin invasion, disease recurrence and metastasis or death (P ≤ 0.027). Furthermore, patients with MALL-negative tumors had significantly decreased overall survival (OS) and disease-free survival (DFS) (P < 0.008 and P < 0.011, respectively). Univariate analysis indicated that MALL expression was significantly associated with OS and DFS. Finally, overexpression of MALL suppressed HCT116 and SW480 cell proliferation and inhibited HCT116 migration. MALL may play a role in colorectal cancer progression as suppression of its expression in tumor tissues negatively impacts colorectal cancer patient survival. Further analyses are required to determine if reduced MALL expression is due to LOH and/or methylation.
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Affiliation(s)
- Xiaoliang Wang
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Junwei Fan
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Fudong Yu
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Feifei Cui
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Xing Sun
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Lin Zhong
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Dongwang Yan
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Chongzhi Zhou
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Guilong Deng
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Bin Wang
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaosheng Qi
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Shuyun Wang
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Lei Qu
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Biao Deng
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Ming Pan
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Jian Chen
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Yupeng Wang
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Guohe Song
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Huamei Tang
- Department of Pathology, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
| | - Zongguang Zhou
- Department of Gastrointestinal Surgery, Laboratory of Digestive Surgery of State Key Laboratory of Biotherapy, West China hospital, Sichuan University, Guo Xue Xiang, Chengdu, Sichuan China
| | - Zhihai Peng
- Department of General Surgery, Shanghai First People's Hospital, Medical College, Shanghai Jiao Tong University, Shanghai, China
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20
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Caceres PS, Benedicto I, Lehmann GL, Rodriguez-Boulan EJ. Directional Fluid Transport across Organ-Blood Barriers: Physiology and Cell Biology. Cold Spring Harb Perspect Biol 2017; 9:a027847. [PMID: 28003183 PMCID: PMC5334253 DOI: 10.1101/cshperspect.a027847] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Directional fluid flow is an essential process for embryo development as well as for organ and organism homeostasis. Here, we review the diverse structure of various organ-blood barriers, the driving forces, transporters, and polarity mechanisms that regulate fluid transport across them, focusing on kidney-, eye-, and brain-blood barriers. We end by discussing how cross talk between barrier epithelial and endothelial cells, perivascular cells, and basement membrane signaling contribute to generate and maintain organ-blood barriers.
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Affiliation(s)
- Paulo S Caceres
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Ignacio Benedicto
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Guillermo L Lehmann
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Enrique J Rodriguez-Boulan
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
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21
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Performance of a Commercially Available MAL Antibody in the Diagnosis of Primary Mediastinal Large B-Cell Lymphoma. Am J Surg Pathol 2017; 41:189-194. [DOI: 10.1097/pas.0000000000000771] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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22
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Enrich C, Rentero C, Grewal T. Annexin A6 in the liver: From the endocytic compartment to cellular physiology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:933-946. [PMID: 27984093 DOI: 10.1016/j.bbamcr.2016.10.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 12/15/2022]
Abstract
Annexin A6 (AnxA6) belongs to the conserved annexin family - a group of Ca2+-dependent membrane binding proteins. AnxA6 is the largest of all annexins and highly expressed in smooth muscle, hepatocytes, endothelial cells and cardiomyocytes. Upon activation, AnxA6 binds to negatively charged phospholipids in a wide range of intracellular localizations, in particular the plasma membrane, late endosomes/pre-lysosomes, but also synaptic vesicles and sarcolemma. In these cellular sites, AnxA6 is believed to contribute to the organization of membrane microdomains, such as cholesterol-rich lipid rafts and confer multiple regulatory functions, ranging from vesicle fusion, endocytosis and exocytosis to programmed cell death and muscle contraction. Growing evidence supports that Ca2+ and Ca2+-binding proteins control endocytosis and autophagy. Their regulatory role seems to operate at the level of the signalling pathways that initiate autophagy or at later stages, when autophagosomes fuse with endolysosomal compartments. The convergence of the autophagic and endocytic vesicles to lysosomes shares several features that depend on Ca2+ originating from lysosomes/late endosomes and seems to depend on proteins that are subsequently activated by this cation. However, the involvement of Ca2+ and its effector proteins in these autophagic and endocytic stages still remains poorly understood. Although AnxA6 makes up almost 0.25% of total protein in the liver, little is known about its function in hepatocytes. Within the endocytic route, we identified AnxA6 in endosomes and autophagosomes of hepatocytes. Hence, AnxA6 and possibly other annexins might represent new Ca2+ effectors that regulate converging steps of autophagy and endocytic trafficking in hepatocytes. This article is part of a Special Issue entitled: ECS Meeting edited by Claus Heizmann, Joachim Krebs and Jacques Haiech.
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Affiliation(s)
- Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cellular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain.
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cellular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - Thomas Grewal
- Faculty of Pharmacy A15, University of Sydney, Sydney, NSW 2006, Australia
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23
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Trotter J, Klein C, Krämer EM. GPI-Anchored Proteins and Glycosphingolipid-Rich Rafts: Platforms for Adhesion and Signaling. Neuroscientist 2016. [DOI: 10.1177/107385840000600410] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Glycosylphosphatidylinositol (GPI)-anchored proteins in mammalian cells play a role in adhesion and signaling. They are sorted in the trans-Golgi network into glycosphingolipid- and cholesterol-rich microdomains termed rafts. Such rafts can be isolated from many cell types including epithelial cells, neural cells, and lymphocytes. In polarized cells, the rafts segregate in distinct regions of the cell. The rafts constitute platforms for signal transduction via raft-associated srcfamily tyrosine kinases. This review compares the sorting, distribution, and signaling of GPI-anchored proteins and rafts in epithelial cells, lymphocytes, and neural cells. A possible involvement of rafts in distinct diseases is also addressed.
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Affiliation(s)
- Jacqueline Trotter
- Department of Neurobiology, University of Heidelberg, Heidelberg, Germany,
| | - Corinna Klein
- Department of Neurobiology, University of Heidelberg, Heidelberg, Germany
| | - Eva-Maria Krämer
- Department of Neurobiology, University of Heidelberg, Heidelberg, Germany
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24
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Wankel B, Ouyang J, Guo X, Hadjiolova K, Miller J, Liao Y, Tham DKL, Romih R, Andrade LR, Gumper I, Simon JP, Sachdeva R, Tolmachova T, Seabra MC, Fukuda M, Schaeren-Wiemers N, Hong WJ, Sabatini DD, Wu XR, Kong X, Kreibich G, Rindler MJ, Sun TT. Sequential and compartmentalized action of Rabs, SNAREs, and MAL in the apical delivery of fusiform vesicles in urothelial umbrella cells. Mol Biol Cell 2016; 27:1621-34. [PMID: 27009205 PMCID: PMC4865319 DOI: 10.1091/mbc.e15-04-0230] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 03/17/2016] [Indexed: 01/28/2023] Open
Abstract
As major urothelial differentiation products, uroplakins are targeted to the apical surface of umbrella cells. Via the sequential actions of Rabs 11, 8, and 27b and their effectors, uroplakin vesicles are transported to a subapical zone above a K20 network and fuse, via a SNARE-mediated and MAL-facilitated step, with the urothelial apical membrane. Uroplakins (UPs) are major differentiation products of urothelial umbrella cells and play important roles in forming the permeability barrier and in the expansion/stabilization of the apical membrane. Further, UPIa serves as a uropathogenic Escherichia coli receptor. Although it is understood that UPs are delivered to the apical membrane via fusiform vesicles (FVs), the mechanisms that regulate this exocytic pathway remain poorly understood. Immunomicroscopy of normal and mutant mouse urothelia show that the UP-delivering FVs contained Rab8/11 and Rab27b/Slac2-a, which mediate apical transport along actin filaments. Subsequently a Rab27b/Slp2-a complex mediated FV–membrane anchorage before SNARE-mediated and MAL-facilitated apical fusion. We also show that keratin 20 (K20), which forms a chicken-wire network ∼200 nm below the apical membrane and has hole sizes allowing FV passage, defines a subapical compartment containing FVs primed and strategically located for fusion. Finally, we show that Rab8/11 and Rab27b function in the same pathway, Rab27b knockout leads to uroplakin and Slp2-a destabilization, and Rab27b works upstream from MAL. These data support a unifying model in which UP cargoes are targeted for apical insertion via sequential interactions with Rabs and their effectors, SNAREs and MAL, and in which K20 plays a key role in regulating vesicular trafficking.
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Affiliation(s)
- Bret Wankel
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Jiangyong Ouyang
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Xuemei Guo
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Krassimira Hadjiolova
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Jeremy Miller
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Yi Liao
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Daniel Kai Long Tham
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Rok Romih
- Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Leonardo R Andrade
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro 21941-902, Brazil
| | - Iwona Gumper
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Jean-Pierre Simon
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Rakhee Sachdeva
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Tanya Tolmachova
- Molecular and Cellular Medicine, Imperial College, London SW7 2AZ, United Kingdom
| | - Miguel C Seabra
- Molecular and Cellular Medicine, Imperial College, London SW7 2AZ, United Kingdom
| | - Mitsunori Fukuda
- Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Sendai 980-8578, Japan
| | - Nicole Schaeren-Wiemers
- Neurobiology Laboratory, Department of Biomedicine, University Hospital Basel, University of Basel, CH-4031 Basel, Switzerland
| | - Wan Jin Hong
- Cancer and Developmental Cell Biology Division, Institute of Molecular and Cell Biology, A*STAR, Biopolis, Singapore 138673
| | - David D Sabatini
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Xue-Ru Wu
- Department of Urology, New York University School of Medicine, New York, NY10016
| | - Xiangpeng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY10016
| | - Gert Kreibich
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Michael J Rindler
- Department of Cell Biology, New York University School of Medicine, New York, NY10016
| | - Tung-Tien Sun
- Department of Cell Biology, New York University School of Medicine, New York, NY10016 Department of Urology, New York University School of Medicine, New York, NY10016 Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY10016 Department of Dermatology, New York University School of Medicine, New York, NY10016
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Nyholm TK. Lipid-protein interplay and lateral organization in biomembranes. Chem Phys Lipids 2015; 189:48-55. [DOI: 10.1016/j.chemphyslip.2015.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 05/27/2015] [Accepted: 05/29/2015] [Indexed: 01/07/2023]
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Reales E, Bernabé-Rubio M, Casares-Arias J, Rentero C, Fernández-Barrera J, Rangel L, Correas I, Enrich C, Andrés G, Alonso MA. The MAL protein is crucial for proper membrane condensation at the ciliary base, which is required for primary cilium elongation. J Cell Sci 2015; 128:2261-70. [DOI: 10.1242/jcs.164970] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 04/30/2015] [Indexed: 01/11/2023] Open
Abstract
ABSTRACT
The base of the primary cilium contains a zone of condensed membranes whose importance is not known. Here, we have studied the involvement of MAL, a tetraspanning protein that exclusively partitions into condensed membrane fractions, in the condensation of membranes at the ciliary base and investigated the importance of these membranes in primary cilium formation. We show that MAL accumulates at the ciliary base of epithelial MDCK cells. Knockdown of MAL expression resulted in a drastic reduction in the condensation of membranes at the ciliary base, the percentage of ciliated cells and the length of the cilia, but did not affect the docking of the centrosome to the plasma membrane or produce missorting of proteins to the pericentriolar zone or to the membrane of the remaining cilia. Rab8 (for which there are two isoforms, Rab8A and Rab8b), IFT88 and IFT20, which are important components of the machinery of ciliary growth, were recruited normally to the ciliary base of MAL-knockdown cells but were unable to elongate the primary cilium correctly. MAL, therefore, is crucial for the proper condensation of membranes at the ciliary base, which is required for efficient primary cilium extension.
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Affiliation(s)
- Elena Reales
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Miguel Bernabé-Rubio
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Javier Casares-Arias
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Carles Rentero
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Barcelona 08036, Spain
| | - Jaime Fernández-Barrera
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Laura Rangel
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Isabel Correas
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Carlos Enrich
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Barcelona 08036, Spain
| | - Germán Andrés
- Electron Microscopy Unit, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
| | - Miguel A. Alonso
- Department of Cell Biology and Immunology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, Madrid 28049, Spain
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Rumah KR, Ma Y, Linden JR, Oo ML, Anrather J, Schaeren-Wiemers N, Alonso MA, Fischetti VA, McClain MS, Vartanian T. The Myelin and Lymphocyte Protein MAL Is Required for Binding and Activity of Clostridium perfringens ε-Toxin. PLoS Pathog 2015; 11:e1004896. [PMID: 25993478 PMCID: PMC4439126 DOI: 10.1371/journal.ppat.1004896] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 04/19/2015] [Indexed: 12/18/2022] Open
Abstract
Clostridium perfringens ε-toxin (ETX) is a potent pore-forming toxin responsible for a central nervous system (CNS) disease in ruminant animals with characteristics of blood-brain barrier (BBB) dysfunction and white matter injury. ETX has been proposed as a potential causative agent for Multiple Sclerosis (MS), a human disease that begins with BBB breakdown and injury to myelin forming cells of the CNS. The receptor for ETX is unknown. Here we show that both binding of ETX to mammalian cells and cytotoxicity requires the tetraspan proteolipid Myelin and Lymphocyte protein (MAL). While native Chinese Hamster Ovary (CHO) cells are resistant to ETX, exogenous expression of MAL in CHO cells confers both ETX binding and susceptibility to ETX-mediated cell death. Cells expressing rat MAL are ~100 times more sensitive to ETX than cells expressing similar levels of human MAL. Insertion of the FLAG sequence into the second extracellular loop of MAL abolishes ETX binding and cytotoxicity. ETX is known to bind specifically and with high affinity to intestinal epithelium, renal tubules, brain endothelial cells and myelin. We identify specific binding of ETX to these structures and additionally show binding to retinal microvasculature and the squamous epithelial cells of the sclera in wild-type mice. In contrast, there is a complete absence of ETX binding to tissues from MAL knockout (MAL-/-) mice. Furthermore, MAL-/- mice exhibit complete resistance to ETX at doses in excess of 1000 times the symptomatic dose for wild-type mice. We conclude that MAL is required for both ETX binding and cytotoxicity.
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Affiliation(s)
- Kareem Rashid Rumah
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
- Laboratory of Bacterial Pathogenesis and Immunology, The Rockefeller University, New York City, New York, United States of America
| | - Yinghua Ma
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
| | - Jennifer R. Linden
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
| | - Myat Lin Oo
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
| | - Josef Anrather
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
| | - Nicole Schaeren-Wiemers
- Neurobiology, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Miguel A. Alonso
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, Madrid, Spain
| | - Vincent A. Fischetti
- Laboratory of Bacterial Pathogenesis and Immunology, The Rockefeller University, New York City, New York, United States of America
| | - Mark S. McClain
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Timothy Vartanian
- Brain and Mind Research Institute, Weill Cornell Medical College, New York City, New York, United States of America
- * E-mail:
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Influenza A virus hemagglutinin and neuraminidase mutually accelerate their apical targeting through clustering of lipid rafts. J Virol 2014; 88:10039-55. [PMID: 24965459 DOI: 10.1128/jvi.00586-14] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED In polarized epithelial cells, influenza A virus hemagglutinin (HA) and neuraminidase (NA) are intrinsically associated with lipid rafts and target the apical plasma membrane for viral assembly and budding. Previous studies have indicated that the transmembrane domain (TMD) and cytoplasmic tail (CT) of HA and NA are required for association with lipid rafts, but the raft dependencies of their apical targeting are controversial. Here, we show that coexpression of HA with NA accelerated their apical targeting through accumulation in lipid rafts. HA was targeted to the apical plasma membrane even when expressed alone, but the kinetics was much slower than that of HA in infected cells. Coexpression experiments revealed that apical targeting of HA and NA was accelerated by their coexpression. The apical targeting of HA was also accelerated by coexpression with M1 but not M2. The mutations in the outer leaflet of the TMD and the deletion of the CT in HA and NA that reduced their association with lipid rafts abolished the acceleration of their apical transport, indicating that the lipid raft association is essential for efficient apical trafficking of HA and NA. An in situ proximity ligation assay (PLA) revealed that HA and NA were accumulated and clustered in the cytoplasmic compartments only when both were associated with lipid rafts. Analysis with mutant viruses containing nonraft HA/NA confirmed these findings. We further analyzed lipid raft markers by in situ PLA and suggest a possible mechanism of the accelerated apical transport of HA and NA via clustering of lipid rafts. IMPORTANCE Lipid rafts serve as sites for viral entry, particle assembly, and budding, leading to efficient viral replication. The influenza A virus utilizes lipid rafts for apical plasma membrane targeting and particle budding. The hemagglutinin (HA) and neuraminidase (NA) of influenza virus, key players for particle assembly, contain determinants for apical sorting and lipid raft association. However, it remains to be elucidated how lipid rafts contribute to the apical trafficking and budding. We investigated the relation of lipid raft association of HA and NA to the efficiency of apical trafficking. We show that coexpression of HA and NA induces their accumulation in lipid rafts and accelerates their apical targeting, and we suggest that the accelerated apical transport likely occurs by clustering of lipid rafts at the TGN. This finding provides the first evidence that two different raft-associated viral proteins induce lipid raft clustering, thereby accelerating apical trafficking of the viral proteins.
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Müsch A. The unique polarity phenotype of hepatocytes. Exp Cell Res 2014; 328:276-83. [PMID: 24956563 DOI: 10.1016/j.yexcr.2014.06.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/09/2014] [Accepted: 06/12/2014] [Indexed: 01/11/2023]
Abstract
Hepatocytes, the main epithelial cell type of the liver, function like all epithelial cells to mediate the vectorial flow of macromolecules into and out of the organ they encompass. They do so by establishing polarized surface domains and by restricting paracellular flow via their tight junctions and cell-cell adhesion. Yet, the cell and tissue organization of hepatocytes differs profoundly from that of most other epithelia, including those of the digestive and urinary tracts, the lung or the breast. The latter form monolayered tissues in which the apical domains of individual cells align around a central continuous luminal cavity that constitutes the tubules and acini characteristic of these organs. Hepatocytes, by contrast, form capillary-sized lumina with multiple neighbors resulting in a branched, tree-like bile canaliculi network that spreads across the liver parenchyme. I will discuss some of the key molecular features that distinguish the hepatocyte polarity phenotype from that of monopolar, columnar epithelia.
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Affiliation(s)
- Anne Müsch
- Albert-Einstein College of Medicine, Department of Cell & Molecular Biology, The Bronx, USA.
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Rodriguez-Boulan E, Macara IG. Organization and execution of the epithelial polarity programme. Nat Rev Mol Cell Biol 2014; 15:225-42. [PMID: 24651541 DOI: 10.1038/nrm3775] [Citation(s) in RCA: 503] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epithelial cells require apical-basal plasma membrane polarity to carry out crucial vectorial transport functions and cytoplasmic polarity to generate different cell progenies for tissue morphogenesis. The establishment and maintenance of a polarized epithelial cell with apical, basolateral and ciliary surface domains is guided by an epithelial polarity programme (EPP) that is controlled by a network of protein and lipid regulators. The EPP is organized in response to extracellular cues and is executed through the establishment of an apical-basal axis, intercellular junctions, epithelial-specific cytoskeletal rearrangements and a polarized trafficking machinery. Recent studies have provided insight into the interactions of the EPP with the polarized trafficking machinery and how these regulate epithelial polarization and depolarization.
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Affiliation(s)
- Enrique Rodriguez-Boulan
- Margaret Dyson Vision Research Institute, Weill Cornell Medical College, 1300 York Avenue, LC-301 New York City, New York 10065, USA
| | - Ian G Macara
- Department of Cell & Developmental Biology, Vanderbilt University Medical Center, 465 21st Avenue South, U 3209 MRB III, Nashville Tennessee 37232, USA
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Abstract
Hepatocytes, like other epithelia, are situated at the interface between the organism's exterior and the underlying internal milieu and organize the vectorial exchange of macromolecules between these two spaces. To mediate this function, epithelial cells, including hepatocytes, are polarized with distinct luminal domains that are separated by tight junctions from lateral domains engaged in cell-cell adhesion and from basal domains that interact with the underlying extracellular matrix. Despite these universal principles, hepatocytes distinguish themselves from other nonstriated epithelia by their multipolar organization. Each hepatocyte participates in multiple, narrow lumina, the bile canaliculi, and has multiple basal surfaces that face the endothelial lining. Hepatocytes also differ in the mechanism of luminal protein trafficking from other epithelia studied. They lack polarized protein secretion to the luminal domain and target single-spanning and glycosylphosphatidylinositol-anchored bile canalicular membrane proteins via transcytosis from the basolateral domain. We compare this unique hepatic polarity phenotype with that of the more common columnar epithelial organization and review our current knowledge of the signaling mechanisms and the organization of polarized protein trafficking that govern the establishment and maintenance of hepatic polarity. The serine/threonine kinase LKB1, which is activated by the bile acid taurocholate and, in turn, activates adenosine monophosphate kinase-related kinases including AMPK1/2 and Par1 paralogues has emerged as a key determinant of hepatic polarity. We propose that the absence of a hepatocyte basal lamina and differences in cell-cell adhesion signaling that determine the positioning of tight junctions are two crucial determinants for the distinct hepatic and columnar polarity phenotypes.
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Affiliation(s)
- Aleksandr Treyer
- Albert Einstein College of Medicine, Department of Developmental and Molecular Biology, Bronx, New York, USA
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Abstract
Tyrosine phosphorylation is one of the key covalent modifications that occur in multicellular organisms. Since its discovery more than 30 years ago, tyrosine phosphorylation has come to be understood as a fundamentally important mechanism of signal transduction and regulation in all eukaryotic cells. The tyrosine kinase Lck (lymphocyte-specific protein tyrosine kinase) plays a crucial role in the T-cell response by transducing early activation signals triggered by TCR (T-cell receptor) engagement. These signals result in the phosphorylation of immunoreceptor tyrosine-based activation motifs present within the cytosolic tails of the TCR-associated CD3 subunits that, once phosphorylated, serve as scaffolds for the assembly of a large supramolecular signalling complex responsible for T-cell activation. The existence of membrane nano- or micro-domains or rafts as specialized platforms for protein transport and cell signalling has been proposed. The present review discusses the signals that target Lck to membrane rafts and the importance of these specialized membranes in the transport of Lck to the plasma membrane, the regulation of Lck activity and the phosphorylation of the TCR.
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Perez Bay AE, Schreiner R, Mazzoni F, Carvajal-Gonzalez JM, Gravotta D, Perret E, Lehmann Mantaras G, Zhu YS, Rodriguez-Boulan EJ. The kinesin KIF16B mediates apical transcytosis of transferrin receptor in AP-1B-deficient epithelia. EMBO J 2013; 32:2125-39. [PMID: 23749212 DOI: 10.1038/emboj.2013.130] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 05/15/2013] [Indexed: 12/20/2022] Open
Abstract
Polarized epithelial cells take up nutrients from the blood through receptors that are endocytosed and recycle back to the basolateral plasma membrane (PM) utilizing the epithelial-specific clathrin adaptor AP-1B. Some native epithelia lack AP-1B and therefore recycle cognate basolateral receptors to the apical PM, where they carry out important functions for the host organ. Here, we report a novel transcytotic pathway employed by AP-1B-deficient epithelia to relocate AP-1B cargo, such as transferrin receptor (TfR), to the apical PM. Lack of AP-1B inhibited basolateral recycling of TfR from common recycling endosomes (CRE), the site of function of AP-1B, and promoted its transfer to apical recycling endosomes (ARE) mediated by the plus-end kinesin KIF16B and non-centrosomal microtubules, and its delivery to the apical membrane mediated by the small GTPase rab11a. Hence, our experiments suggest that the apical recycling pathway of epithelial cells is functionally equivalent to the rab11a-dependent TfR recycling pathway of non-polarized cells. They define a transcytotic pathway important for the physiology of native AP-1B-deficient epithelia and report the first microtubule motor involved in transcytosis.
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Affiliation(s)
- Andres E Perez Bay
- Department of Ophthalmology, Margaret Dyson Vision Research Institute, Weill Cornell Medical College, New York, NY 10065, USA
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Aranda JF, Reglero-Real N, Marcos-Ramiro B, Ruiz-Sáenz A, Fernández-Martín L, Bernabé-Rubio M, Kremer L, Ridley AJ, Correas I, Alonso MA, Millán J. MYADM controls endothelial barrier function through ERM-dependent regulation of ICAM-1 expression. Mol Biol Cell 2013; 24:483-94. [PMID: 23264465 PMCID: PMC3571871 DOI: 10.1091/mbc.e11-11-0914] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 11/15/2012] [Accepted: 12/14/2012] [Indexed: 11/18/2022] Open
Abstract
The endothelium maintains a barrier between blood and tissue that becomes more permeable during inflammation. Membrane rafts are ordered assemblies of cholesterol, glycolipids, and proteins that modulate proinflammatory cell signaling and barrier function. In epithelial cells, the MAL family members MAL, MAL2, and myeloid-associated differentiation marker (MYADM) regulate the function and dynamics of ordered membrane domains. We analyzed the expression of these three proteins in human endothelial cells and found that only MYADM is expressed. MYADM was confined in ordered domains at the plasma membrane, where it partially colocalized with filamentous actin and cell-cell junctions. Small interfering RNA (siRNA)-mediated MYADM knockdown increased permeability, ICAM-1 expression, and leukocyte adhesion, all of which are features of an inflammatory response. Barrier function decrease in MYADM-silenced cells was dependent on ICAM-1 expression. Membrane domains and the underlying actin cytoskeleton can regulate each other and are connected by ezrin, radixin, and moesin (ERM) proteins. In endothelial cells, MYADM knockdown induced ERM activation. Triple-ERM knockdown partially inhibited ICAM-1 increase induced by MYADM siRNA. Importantly, ERM knockdown also reduced ICAM-1 expression in response to the proinflammatory cytokine tumor necrosis factor-α. MYADM therefore regulates the connection between the plasma membrane and the cortical cytoskeleton and so can control the endothelial inflammatory response.
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Affiliation(s)
- Juan F. Aranda
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Natalia Reglero-Real
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Beatriz Marcos-Ramiro
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Ana Ruiz-Sáenz
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Laura Fernández-Martín
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Miguel Bernabé-Rubio
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Leonor Kremer
- Centro Nacional de Biotecnología. Consejo Superior de Investigaciones Científicas, Cantoblanco, 28049 Madrid, Spain
| | - Anne J. Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, United Kingdom
| | - Isabel Correas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Miguel A. Alonso
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Jaime Millán
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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Suzuki M, Shiraishi K, Eguchi A, Ikeda K, Mori T, Yoshimoto K, Ohba Y, Yamada T, Ito T, Baba Y, Baba H. Aberrant methylation of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer. Oncol Rep 2013; 29:1308-14. [PMID: 23381221 PMCID: PMC3621652 DOI: 10.3892/or.2013.2266] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 12/21/2012] [Indexed: 12/23/2022] Open
Abstract
Genome-wide DNA hypomethylation and gene hypermethylation play important roles in instability and carcinogenesis. Methylation in long interspersed nucleotide element 1 (LINE-1) is a good indicator of the global DNA methylation level within a cell. Slit homolog 2 (SLIT2), myelin and lymphocyte protein gene (MAL) and insulin-like growth factor binding protein 7 (IGFBP7) are known to be hypermethylated in various malignancies. The aim of the present study was to assess the precise methylation levels of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer (NSCLC) using a pyrosequencing assay. Methylation of all regions was examined in 56 primary NSCLCs using a pyrosequencing assay. Changes in mRNA expression levels of SLIT2, MAL and IGFBP7 were measured before and after treatment with a demethylating agent. Methylation of these genes was also examined in 9 lung cancer cell lines using RT-PCR and a pyrosequencing assay. Frequencies of hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7, defined by predetermined cut off values, were 55, 64, 46 and 54% in NSCLCs, respectively and exhibited tumor-specific features. The hypermethylation of all genes was well correlated with changes in expression. The methylation level and frequency of MAL were significantly higher in smokers and in patients without EGFR mutations. Through accurate measurement of methylation levels using pyrosequencing, hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7 were frequently detected in NSCLCs and associated with various clinical features. Analysis of the methylation profiles of these genes may, therefore, provide novel opportunities for the therapy of NSCLCs.
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Affiliation(s)
- Makoto Suzuki
- Department of Thoracic Surgery, Graduate School of Medical Science, Kumamoto University, Kumamoto 860-8556, Japan.
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Takiar V, Mistry K, Carmosino M, Schaeren-Wiemers N, Caplan MJ. VIP17/MAL expression modulates epithelial cyst formation and ciliogenesis. Am J Physiol Cell Physiol 2012; 303:C862-71. [PMID: 22895261 PMCID: PMC3469709 DOI: 10.1152/ajpcell.00338.2011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 08/13/2012] [Indexed: 11/22/2022]
Abstract
The polarized organization of epithelial cells is required for vectorial solute transport and may be altered in renal cystic diseases. Vesicle integral protein of 17 kDa (VIP17/MAL) is involved in apical vesicle transport. VIP17/MAL overexpression in vivo results in renal cystogenesis of unknown etiology. Renal cystogenesis can occur as a consequence of defects of the primary cilium. To explore the role of VIP17/MAL in renal cystogenesis and ciliogenesis, we examined the polarization and ciliary morphology of wild-type and VIP17/MAL overexpressing Madin-Darby canine kidney renal epithelial cells grown in two-dimensional (2D) and three-dimensional (3D) cyst culture. VIP17/MAL is apically localized when expressed in cells maintained in 2D and 3D culture. VIP17/MAL overexpressing cells produce more multilumen cysts compared with controls. While the distributions of basolateral markers are not affected, VIP17/MAL expression results in aberrant sorting of the apical marker gp135 to the primary cilium. VIP17/MAL overexpression is also associated with shortened or absent cilia. Immunofluorescence analysis performed on kidney sections from VIP17/MAL transgenic mice also demonstrates fewer and shortened cilia within dilated lumens (P < 0.01). These studies demonstrate that VIP17/MAL overexpression results in abnormal cilium and cyst development, in vitro and in vivo, suggesting that VIP17/MAL overexpressing mice may develop cysts secondary to a ciliary defect.
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Affiliation(s)
- Vinita Takiar
- Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut 06520-8026, USA
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Abstract
The polarized distribution of proteins and lipids at the surface membrane of epithelial cells results in the formation of an apical and a basolateral domain, which are separated by tight junctions. The generation and maintenance of epithelial polarity require elaborate mechanisms that guarantee correct sorting and vectorial delivery of cargo molecules. This dynamic process involves the interaction of sorting signals with sorting machineries and the formation of transport carriers. Here we review the recent advances in the field of polarized sorting in epithelial cells. We especially highlight the role of lipid rafts in apical sorting.
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Yaffe Y, Shepshelovitch J, Nevo-Yassaf I, Yeheskel A, Shmerling H, Kwiatek JM, Gaus K, Pasmanik-Chor M, Hirschberg K. The MARVEL transmembrane motif of occludin mediates oligomerization and targeting to the basolateral surface in epithelia. J Cell Sci 2012; 125:3545-56. [PMID: 22492786 DOI: 10.1242/jcs.100289] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Occludin (Ocln), a MARVEL-motif-containing protein, is found in all tight junctions. MARVEL motifs are comprised of four transmembrane helices associated with the localization to or formation of diverse membrane subdomains by interacting with the proximal lipid environment. The functions of the Ocln MARVEL motif are unknown. Bioinformatics sequence- and structure-based analyses demonstrated that the MARVEL domain of Ocln family proteins has distinct evolutionarily conserved sequence features that are consistent with its basolateral membrane localization. Live-cell microscopy, fluorescence resonance energy transfer (FRET) and bimolecular fluorescence complementation (BiFC) were used to analyze the intracellular distribution and self-association of fluorescent-protein-tagged full-length human Ocln or the Ocln MARVEL motif excluding the cytosolic C- and N-termini (amino acids 60-269, FP-MARVEL-Ocln). FP-MARVEL-Ocln efficiently arrived at the plasma membrane (PM) and was sorted to the basolateral PM in filter-grown polarized MDCK cells. A series of conserved aromatic amino acids within the MARVEL domain were found to be associated with Ocln dimerization using BiFC. FP-MARVEL-Ocln inhibited membrane pore growth during Triton-X-100-induced solubilization and was shown to increase the membrane-ordered state using Laurdan, a lipid dye. These data demonstrate that the Ocln MARVEL domain mediates self-association and correct sorting to the basolateral membrane.
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Affiliation(s)
- Yakey Yaffe
- Department of Pathology, Sackler School of Medicine, Tel-Aviv 69978, Israel
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40
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Zhou G, Liang FX, Romih R, Wang Z, Liao Y, Ghiso J, Luque-Garcia JL, Neubert TA, Kreibich G, Alonso MA, Schaeren-Wiemers N, Sun TT. MAL facilitates the incorporation of exocytic uroplakin-delivering vesicles into the apical membrane of urothelial umbrella cells. Mol Biol Cell 2012; 23:1354-66. [PMID: 22323295 PMCID: PMC3315800 DOI: 10.1091/mbc.e11-09-0823] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
MAL, suggested to play a key role in the apical sorting of membrane proteins, is not involved in the apical sorting of uroplakins. Instead, it plays an important role in facilitating the incorporation of the uroplakin-delivering exocytic vesicles into the apical surface of terminally differentiated urothelial umbrella cells. The apical surface of mammalian bladder urothelium is covered by large (500–1000 nm) two-dimensional (2D) crystals of hexagonally packed 16-nm uroplakin particles (urothelial plaques), which play a role in permeability barrier function and uropathogenic bacterial binding. How the uroplakin proteins are delivered to the luminal surface is unknown. We show here that myelin-and-lymphocyte protein (MAL), a 17-kDa tetraspan protein suggested to be important for the apical sorting of membrane proteins, is coexpressed with uroplakins in differentiated urothelial cell layers. MAL depletion in Madin–Darby canine kidney cells did not affect, however, the apical sorting of uroplakins, but it decreased the rate by which uroplakins were inserted into the apical surface. Moreover, MAL knockout in vivo led to the accumulation of fusiform vesicles in mouse urothelial superficial umbrella cells, whereas MAL transgenic overexpression in vivo led to enhanced exocytosis and compensatory endocytosis, resulting in the accumulation of the uroplakin-degrading multivesicular bodies. Finally, although MAL and uroplakins cofloat in detergent-resistant raft fractions, they are associated with distinct plaque and hinge membrane subdomains, respectively. These data suggest a model in which 1) MAL does not play a role in the apical sorting of uroplakins; 2) the propensity of uroplakins to polymerize forming 16-nm particles and later large 2D crystals that behave as detergent-resistant (giant) rafts may drive their apical targeting; 3) the exclusion of MAL from the expanding 2D crystals of uroplakins explains the selective association of MAL with the hinge areas in the uroplakin-delivering fusiform vesicles, as well as at the apical surface; and 4) the hinge-associated MAL may play a role in facilitating the incorporation of the exocytic uroplakin vesicles into the corresponding hinge areas of the urothelial apical surface.
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Affiliation(s)
- Ge Zhou
- Department of Cell Biology, NYU Cancer Institute, NYU Langone Medical Center, New York University, New York, NY 10016, USA
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Surma MA, Klose C, Simons K. Lipid-dependent protein sorting at the trans-Golgi network. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1821:1059-67. [PMID: 22230596 DOI: 10.1016/j.bbalip.2011.12.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 12/02/2011] [Accepted: 12/03/2011] [Indexed: 12/14/2022]
Abstract
In eukaryotic cells, the trans-Golgi network serves as a sorting station for post-Golgi traffic. In addition to coat- and adaptor-mediated mechanisms, studies in mammalian epithelial cells and yeast have provided evidence for lipid-dependent protein sorting as a major delivery mechanism for cargo sorting to the cell surface. The mechanism for lipid-mediated sorting is the generation of raft platforms of sphingolipids, sterols and specific sets of cargo proteins by phase segregation in the TGN. Here, we review the evidence for such lipid-raft-based sorting at the TGN, as well as their involvement in the formation of TGN-to-PM transport carriers. This article is part of a Special Issue entitled Lipids and Vesicular Transport.
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Affiliation(s)
- Michal A Surma
- Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, 01307 Dresden, Germany
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Séron K, Couturier C, Belouzard S, Bacart J, Monté D, Corset L, Bocquet O, Dam J, Vauthier V, Lecœur C, Bailleul B, Hoflack B, Froguel P, Jockers R, Rouillé Y. Endospanins regulate a postinternalization step of the leptin receptor endocytic pathway. J Biol Chem 2011; 286:17968-81. [PMID: 21454707 PMCID: PMC3093871 DOI: 10.1074/jbc.m111.224857] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 03/07/2011] [Indexed: 12/22/2022] Open
Abstract
Endospanin-1 is a negative regulator of the cell surface expression of leptin receptor (OB-R), and endospanin-2 is a homologue of unknown function. We investigated the mechanism for endospanin-1 action in regulating OB-R cell surface expression. Here we show that endospanin-1 and -2 are small integral membrane proteins that localize in endosomes and the trans-Golgi network. Antibody uptake experiments showed that both endospanins are transported to the plasma membrane and then internalized into early endosomes but do not recycle back to the trans-Golgi network. Overexpression of endospanin-1 or endospanin-2 led to a decrease of OB-R cell surface expression, whereas shRNA-mediated depletion of each protein increased OB-R cell surface expression. This increased cell surface expression was not observed with OB-Ra mutants defective in endocytosis or with transferrin and EGF receptors. Endospanin-1 or endospanin-2 depletion did not change the internalization rate of OB-Ra but slowed down its lysosomal degradation. Thus, both endospanins are regulators of postinternalization membrane traffic of the endocytic pathway of OB-R.
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Affiliation(s)
- Karin Séron
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8204, 59021 Lille, France
- the Institut National de la Santé et de la Recherche Médicale Unité 1019, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Cyril Couturier
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
- the Institut Cochin, Unité Mixte de Recherche 8104, CNRS, Department of Cell Biology, Université Paris Descartes, 75014 Paris, France
- INSERM Unité 1016, 75014 Paris, France
| | - Sandrine Belouzard
- the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8204, 59021 Lille, France
- the Institut National de la Santé et de la Recherche Médicale Unité 1019, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Johan Bacart
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Didier Monté
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
- CNRS, Unité Mixte de Recherche 8161, 59021 Lille, France
| | - Laetitia Corset
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Olivier Bocquet
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Julie Dam
- the Institut Cochin, Unité Mixte de Recherche 8104, CNRS, Department of Cell Biology, Université Paris Descartes, 75014 Paris, France
- INSERM Unité 1016, 75014 Paris, France
| | - Virginie Vauthier
- the Institut Cochin, Unité Mixte de Recherche 8104, CNRS, Department of Cell Biology, Université Paris Descartes, 75014 Paris, France
- INSERM Unité 1016, 75014 Paris, France
| | - Cécile Lecœur
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
| | - Bernard Bailleul
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
- INSERM Unité 1011, 59021 Lille, France
| | - Bernard Hoflack
- the Biotechnological Center, Dresden University of Technology, 01307 Dresden, Germany, and
| | - Philippe Froguel
- From the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8199, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
- the Department of Genomic Medicine, Hammersmith Hospital, Imperial College London, London SW7 2AZ, United Kingdom
| | - Ralf Jockers
- the Institut Cochin, Unité Mixte de Recherche 8104, CNRS, Department of Cell Biology, Université Paris Descartes, 75014 Paris, France
- INSERM Unité 1016, 75014 Paris, France
| | - Yves Rouillé
- the Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8204, 59021 Lille, France
- the Institut National de la Santé et de la Recherche Médicale Unité 1019, 59021 Lille, France
- the Université Lille Nord de France, Lille 59021, France
- the Institut Pasteur de Lille, 59021 Lille, France
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Antón OM, Andrés-Delgado L, Reglero-Real N, Batista A, Alonso MA. MAL protein controls protein sorting at the supramolecular activation cluster of human T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2011; 186:6345-56. [PMID: 21508261 DOI: 10.4049/jimmunol.1003771] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
T cell membrane receptors and signaling molecules assemble at the immunological synapse (IS) in a supramolecular activation cluster (SMAC), organized into two differentiated subdomains: the central SMAC (cSMAC), with the TCR, Lck, and linker for activation of T cells (LAT), and the peripheral SMAC (pSMAC), with adhesion molecules. The mechanism of protein sorting to the SMAC subdomains is still unknown. MAL forms part of the machinery for protein targeting to the plasma membrane by specialized mechanisms involving condensed membranes or rafts. In this article, we report our investigation of the dynamics of MAL during the formation of the IS and its role in SMAC assembly in the Jurkat T cell line and human primary T cells. We observed that under normal conditions, a pool of MAL rapidly accumulates at the cSMAC, where it colocalized with condensed membranes, as visualized with the membrane fluorescent probe Laurdan. Mislocalization of MAL to the pSMAC greatly reduced membrane condensation at the cSMAC and redistributed machinery involved in docking microtubules or transport vesicles from the cSMAC to the pSMAC. As a consequence of these alterations, the raft-associated molecules Lck and LAT, but not the TCR, were missorted to the pSMAC. MAL, therefore, regulates membrane order and the distribution of microtubule and transport vesicle docking machinery at the IS and, by doing so, ensures correct protein sorting of Lck and LAT to the cSMAC.
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Affiliation(s)
- Olga M Antón
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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Aranda JF, Reglero-Real N, Kremer L, Marcos-Ramiro B, Ruiz-Sáenz A, Calvo M, Enrich C, Correas I, Millán J, Alonso MA. MYADM regulates Rac1 targeting to ordered membranes required for cell spreading and migration. Mol Biol Cell 2011; 22:1252-62. [PMID: 21325632 PMCID: PMC3078064 DOI: 10.1091/mbc.e10-11-0910] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Membrane organization into condensed domains or rafts provides molecular platforms for selective recruitment of proteins. Cell migration is a general process that requires spatiotemporal targeting of Rac1 to membrane rafts. The protein machinery responsible for making rafts competent to recruit Rac1 remains elusive. Some members of the MAL family of proteins are involved in specialized processes dependent on this type of membrane. Because condensed membrane domains are a general feature of the plasma membrane of all mammalian cells, we hypothesized that MAL family members with ubiquitous expression and plasma membrane distribution could be involved in the organization of membranes for cell migration. We show that myeloid-associated differentiation marker (MYADM), a protein with unique features within the MAL family, colocalizes with Rac1 in membrane protrusions at the cell surface and distributes in condensed membranes. MYADM knockdown (KD) cells had altered membrane condensation and showed deficient incorporation of Rac1 to membrane raft fractions and, similar to Rac1 KD cells, exhibited reduced cell spreading and migration. Results of rescue-of-function experiments by expression of MYADM or active Rac1L61 in cells knocked down for Rac1 or MYADM, respectively, are consistent with the idea that MYADM and Rac1 act on parallel pathways that lead to similar functional outcomes.
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Affiliation(s)
- Juan F Aranda
- Centro de Biología Molecular Severo Ochoa, Cantoblanco, 28049 Madrid, Spain
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46
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Oddi S, Dainese E, Fezza F, Lanuti M, Barcaroli D, De Laurenzi V, Centonze D, Maccarrone M. Functional characterization of putative cholesterol binding sequence (CRAC) in human type-1 cannabinoid receptor. J Neurochem 2011; 116:858-65. [PMID: 21214565 DOI: 10.1111/j.1471-4159.2010.07041.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Endocannabinoid signaling modulates a variety of neuroinflammatory and neurodegenerative diseases, mainly through the activation of type-1 and type-2 (CB(1)R and CB(2)R) cannabinoid receptors. CB(1)R is negatively regulated by membrane cholesterol, while CB(2)R is unaffected. Here, we identified in the transmembrane helix 7 of human CBRs a consensus sequence already known in other proteins as cholesterol recognition/interaction amino acid sequence and consensus pattern. As this motif is different in the two CBR subtypes, we mutated lysine 402 of CB(1)R into glycine, to obtain a cholesterol recognition/interaction amino acid sequence and consensus similar to that of CB(2)R. Both mutated and wild-type receptors were transiently expressed in human neuronal SH-SY5Y cells, and their localization and functioning were investigated using biochemical assays and immunofluorescence labelling. We found a reduced propensity of the mutant CB(1)R to reside in cholesterol-rich microdomains and, by means of fluorescence recovery after photobleaching analysis, we documented its loss of sensitivity to increased membrane cholesterol content. These results seem to uncover the existence of a new structural determinant in cannabinoid receptors, that is likely implicated in directing their interaction with cholesterol-rich microdomains of cell membranes.
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Affiliation(s)
- Sergio Oddi
- Department of Biomedical Sciences, University of Teramo, Teramo, Italy
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47
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Formin INF2 regulates MAL-mediated transport of Lck to the plasma membrane of human T lymphocytes. Blood 2010; 116:5919-29. [DOI: 10.1182/blood-2010-08-300665] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Expression of the src-family kinase lymphocyte-specific protein tyrosine kinase (Lck) at the plasma membrane is essential for it to fulfill its pivotal role in signal transduction in T lymphocytes. MAL, an integral membrane protein expressed in specific types of lymphoma, has been shown to play an important role in targeting Lck to the plasma membrane. Here we report that MAL interacts with Inverted Formin2 (INF2), a formin with the atypical property of promoting not only actin polymerization but also its depolymerization. In Jurkat T cells, INF2 colocalizes with MAL at the cell periphery and pericentriolar endosomes and along microtubules. Videomicroscopic analysis revealed that the MAL+ vesicles transporting Lck to the plasma membrane move along microtubule tracks. Knockdown of INF2 greatly reduced the formation of MAL+ transport vesicles and the levels of Lck at the plasma membrane and impaired formation of a normal immunologic synapse. The actin polymerization and depolymerization activities of INF2 were both required for efficient Lck targeting. Cdc42 and Rac1, which bind to INF2, regulate Lck transport in both Jurkat and primary human T cells. Thus, INF2 collaborates with MAL in the formation of specific carriers for targeting Lck to the plasma membrane in a process regulated by Cdc42 and Rac1.
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48
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Cao W, Zhang ZY, Xu Q, Sun Q, Yan M, Zhang J, Zhang P, Han ZG, Chen WT. Epigenetic silencing of MAL, a putative tumor suppressor gene, can contribute to human epithelium cell carcinoma. Mol Cancer 2010; 9:296. [PMID: 21092172 PMCID: PMC3002926 DOI: 10.1186/1476-4598-9-296] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 11/22/2010] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND To identify new and useful candidate biomarkers in head and neck squamous cell carcinoma (HNSCC), we performed a genome-wide survey and found that Myelin and lymphocyte-associated protein (MAL) was a gene that was markedly down-regulated in HNSCC. Hence, we investigated the mechanism of MAL silencing and the effects of MAL on the proliferation, invasion, and apoptotic potential in HNSCC. RESULTS MAL was significantly down-regulated in 91.7% of HNSCC specimens at the mRNA level as compared with adjacent normal tissues (P = 0.0004). Moreover, the relative transcript levels of the MAL gene were remarkably decreased by five-fold in nine HNSCC cell lines as compared with normal head and neck epithelium cells. MAL gene expression was restored in 44%, 67%, and 89% in HNSCC cell lines treated with TSA, 5-Aza-dC, and TSA plus 5-Aza-dC, respectively. Furthermore, bisulfate-treated DNA sequencing demonstrated that the two CpG islands (that is, M1 and M2) located in MAL promoter region were completely methylated in the HNSCC cell lines (CpG methylated ratio was more than 90%), and only one CpG island (that is, M1) was partially methylated in HNSCC tissues (CpG methylated ratio between 20% and 90%). A significant reduction in cell proliferation and a change in the cell cycle profile were also observed in MAL transfectants. Matrigel assay demonstrated that the invasiveness of HNSCC cells significantly decreased. A significant increase in the population of apoptotic cells was observed in MAL transfected cells. The exogenous expression of the MAL gene suppressed malignant phenotypes, while the cell death induced by MAL gene transfer was a result of apoptosis as demonstrated by the induction of cleavage of the poly (that is, ADP-ribose) polymerase. Additionally, tumor growth was suppressed in cells expressing MAL as compared with cells not expressing MAL. CONCLUSION Our data suggest that the epigenetic inactivation of MAL, as a candidate tumor suppressor gene, can contribute to human epithelial cell carcinoma and may be served as a biomarker in HNSCC.
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MESH Headings
- Apoptosis/genetics
- Apoptosis/physiology
- Blotting, Western
- Carcinoma/genetics
- Carcinoma/metabolism
- Carcinoma, Squamous Cell
- Cell Cycle/genetics
- Cell Cycle/physiology
- Cell Line, Tumor
- Cell Proliferation
- DNA Methylation/genetics
- Epigenesis, Genetic/genetics
- Gene Expression Regulation, Neoplastic/genetics
- Gene Expression Regulation, Neoplastic/physiology
- Head and Neck Neoplasms/genetics
- Head and Neck Neoplasms/metabolism
- Humans
- Membrane Transport Proteins/genetics
- Membrane Transport Proteins/metabolism
- Microscopy, Confocal
- Myelin Proteins/genetics
- Myelin Proteins/metabolism
- Myelin and Lymphocyte-Associated Proteolipid Proteins
- Neoplasms, Squamous Cell/genetics
- Neoplasms, Squamous Cell/metabolism
- Polymerase Chain Reaction
- Promoter Regions, Genetic/genetics
- Proteolipids/genetics
- Proteolipids/metabolism
- RNA, Messenger/genetics
- Squamous Cell Carcinoma of Head and Neck
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Affiliation(s)
- Wei Cao
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Zhi-yuan Zhang
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Qin Xu
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Qiang Sun
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Ming Yan
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Jun Zhang
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Ping Zhang
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
| | - Ze-guang Han
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
- Chinese National Human Genome Center at Shanghai, 201203, China
| | - Wan-tao Chen
- Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology, Shanghai 200011, China
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49
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Carmosino M, Rizzo F, Procino G, Basco D, Valenti G, Forbush B, Schaeren-Wiemers N, Caplan MJ, Svelto M. MAL/VIP17, a new player in the regulation of NKCC2 in the kidney. Mol Biol Cell 2010; 21:3985-97. [PMID: 20861303 PMCID: PMC2982131 DOI: 10.1091/mbc.e10-05-0456] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The renal-specific Na+-K+-2Cl- cotransporter (NKCC2) is the major salt transport pathway of the apical membrane of the mammalian thick ascending limb of Henle's loop. Here, we analyze the role of the tetraspan protein myelin and lymphocytes-associated protein (MAL)/VIP17 in the regulation of NKCC2. We demonstrated that 1) NKCC2 and MAL/VIP17 colocalize and coimmunoprecipitate in Lilly Laboratories cell porcine kidney cells (LLC-PK1) as well as in rat kidney medullae, 2) a 150-amino acid stretch of NKCC2 C-terminal tail is involved in the interaction with MAL/VIP17, 3) MAL/VIP17 increases the cell surface retention of NKCC2 by attenuating its internalization, and 4) this coincides with an increase in cotransporter phosphorylation. Interestingly, overexpression of MAL/VIP17 in the kidney of transgenic mice results in cysts formation in distal nephron structures consistent with the hypothesis that MAL/VIP17 plays an important role in apical sorting or in maintaining the stability of the apical membrane. The NKCC2 expressed in these mice was highly glycosylated and phosphorylated, suggesting that MAL/VIP17 also is involved in the stabilization of NKCC2 at the apical membrane in vivo. Thus, the involvement of MAL/VIP17 in the activation and surface expression of NKCC2 could play an important role in the regulated absorption of Na+ and Cl- in the kidney.
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Affiliation(s)
- Monica Carmosino
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT 06511, USA.
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50
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Weisz OA, Rodriguez-Boulan E. Apical trafficking in epithelial cells: signals, clusters and motors. J Cell Sci 2010; 122:4253-66. [PMID: 19923269 DOI: 10.1242/jcs.032615] [Citation(s) in RCA: 228] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In the early days of epithelial cell biology, researchers working with kidney and/or intestinal epithelial cell lines and with hepatocytes described the biosynthetic and recycling routes followed by apical and basolateral plasma membrane (PM) proteins. They identified the trans-Golgi network and recycling endosomes as the compartments that carried out apical-basolateral sorting. They described complex apical sorting signals that promoted association with lipid rafts, and simpler basolateral sorting signals resembling clathrin-coated-pit endocytic motifs. They also noticed that different epithelial cell types routed their apical PM proteins very differently, using either a vectorial (direct) route or a transcytotic (indirect) route. Although these original observations have generally held up, recent studies have revealed interesting complexities in the routes taken by apically destined proteins and have extended our understanding of the machinery required to sustain these elaborate sorting pathways. Here, we critically review the current status of apical trafficking mechanisms and discuss a model in which clustering is required to recruit apical trafficking machineries. Uncovering the mechanisms responsible for polarized trafficking and their epithelial-specific variations will help understand how epithelial functional diversity is generated and the pathogenesis of many human diseases.
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Affiliation(s)
- Ora A Weisz
- Department of Medicine and Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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