1
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Brunet T, Booth DS. Cell polarity in the protist-to-animal transition. Curr Top Dev Biol 2023; 154:1-36. [PMID: 37100515 DOI: 10.1016/bs.ctdb.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
A signature feature of the animal kingdom is the presence of epithelia: sheets of polarized cells that both insulate the organism from its environment and mediate interactions with it. Epithelial cells display a marked apico-basal polarity, which is highly conserved across the animal kingdom, both in terms of morphology and of molecular regulators. How did this architecture first evolve? Although the last eukaryotic common ancestor almost certainly possessed a simple form of apico-basal polarity (marked by the presence of one or several flagella at a single cellular pole), comparative genomics and evolutionary cell biology reveal that the polarity regulators of animal epithelial cells have a surprisingly complex and stepwise evolutionary history. Here, we retrace their evolutionary assembly. We suggest that the "polarity network" that polarized animal epithelial cells evolved by integration of initially independent cellular modules that evolved at distinct steps of our evolutionary ancestry. The first module dates back to the last common ancestor of animals and amoebozoans and involved Par1, extracellular matrix proteins, and the integrin-mediated adhesion complex. Other regulators, such as Cdc42, Dlg, Par6 and cadherins evolved in ancient unicellular opisthokonts, and might have first been involved in F-actin remodeling and filopodial dynamics. Finally, the bulk of "polarity proteins" as well as specialized adhesion complexes evolved in the metazoan stem-line, in concert with the newly evolved intercellular junctional belts. Thus, the polarized architecture of epithelia can be understood as a palimpsest of components of distinct histories and ancestral functions, which have become tightly integrated in animal tissues.
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2
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Pickett MA, Sallee MD, Cote L, Naturale VF, Akpinaroglu D, Lee J, Shen K, Feldman JL. Separable mechanisms drive local and global polarity establishment in the Caenorhabditiselegans intestinal epithelium. Development 2022; 149:dev200325. [PMID: 36264257 PMCID: PMC9845746 DOI: 10.1242/dev.200325] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 10/06/2022] [Indexed: 11/17/2022]
Abstract
Apico-basolateral polarization is essential for epithelial cells to function as selective barriers and transporters, and to provide mechanical resilience to organs. Epithelial polarity is established locally, within individual cells to establish distinct apical, junctional and basolateral domains, and globally, within a tissue where cells coordinately orient their apico-basolateral axes. Using live imaging of endogenously tagged proteins and tissue-specific protein depletion in the Caenorhabditiselegans embryonic intestine, we found that local and global polarity establishment are temporally and genetically separable. Local polarity is initiated prior to global polarity and is robust to perturbation. PAR-3 is required for global polarization across the intestine but local polarity can arise in its absence, as small groups of cells eventually established polarized domains in PAR-3-depleted intestines in a HMR-1 (E-cadherin)-dependent manner. Despite the role of PAR-3 in localizing PKC-3 to the apical surface, we additionally found that PAR-3 and PKC-3/aPKC have distinct roles in the establishment and maintenance of local and global polarity. Taken together, our results indicate that different mechanisms are required for local and global polarity establishment in vivo.
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Affiliation(s)
- Melissa A. Pickett
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Department of Biological Sciences, San Jose State University, San Jose, CA 95112, USA
| | - Maria D. Sallee
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Lauren Cote
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | | | | | - Joo Lee
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, CA 94305, USA
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3
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Pasapera AM, Heissler SM, Eto M, Nishimura Y, Fischer RS, Thiam HR, Waterman CM. MARK2 regulates directed cell migration through modulation of myosin II contractility and focal adhesion organization. Curr Biol 2022; 32:2704-2718.e6. [PMID: 35594862 DOI: 10.1016/j.cub.2022.04.088] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 02/23/2022] [Accepted: 04/28/2022] [Indexed: 12/11/2022]
Abstract
Cancer cell migration during metastasis is mediated by a highly polarized cytoskeleton. MARK2 and its invertebrate homolog Par1B are kinases that regulate the microtubule cytoskeleton to mediate polarization of neurons in mammals and embryos in invertebrates. However, the role of MARK2 in cancer cell migration is unclear. Using osteosarcoma cells, we found that in addition to its known localizations on microtubules and the plasma membrane, MARK2 also associates with the actomyosin cytoskeleton and focal adhesions. Cells depleted of MARK proteins demonstrated that MARK2 promotes phosphorylation of both myosin II and the myosin phosphatase targeting subunit MYPT1 to synergistically drive myosin II contractility and stress fiber formation in cells. Studies with isolated proteins showed that MARK2 directly phosphorylates myosin II regulatory light chain, while its effects on MYPT1 phosphorylation are indirect. Using a mutant lacking the membrane-binding domain, we found that membrane association is required for focal adhesion targeting of MARK2, where it specifically enhances cell protrusion by promoting FAK phosphorylation and formation of focal adhesions oriented in the direction of migration to mediate directionally persistent cell motility. Together, our results define MARK2 as a master regulator of the actomyosin and microtubule cytoskeletal systems and focal adhesions to mediate directional cancer cell migration.
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Affiliation(s)
- Ana M Pasapera
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA
| | - Sarah M Heissler
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA; Department of Physiology and Cell Biology, The Ohio State University College of Medicine, 370 W. 9th Avenue, Columbus, OH 43210, USA
| | - Masumi Eto
- Department of Veterinary Medicine, Okayama University of Science, 1-3 Ikoino-oka, Imabari, Ehime 794-8555, Japan
| | - Yukako Nishimura
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA; Division of Developmental Physiology, Institute for Genetic Medicine, Hokkaido University, Kita 15, Nishi 7, Kita-Ku, Sapporo, Hokkaido 060-0815, Japan
| | - Robert S Fischer
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA
| | - Hawa R Thiam
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA
| | - Clare M Waterman
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Building 50, South Drive, Room 4537, MSC 8019, Bethesda, MD 20892, USA.
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4
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Tanimizu N. The neonatal liver: Normal development and response to injury and disease. Semin Fetal Neonatal Med 2022; 27:101229. [PMID: 33745829 DOI: 10.1016/j.siny.2021.101229] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The liver emerges from the ventral foregut endoderm around 3 weeks in human and 1 week in mice after fertilization. The fetal liver works as a hematopoietic organ and then develops functions required for performing various metabolic reactions in late fetal and neonatal periods. In parallel with functional differentiation, the liver establishes three dimensional tissue structures. In particular, establishment of the bile excretion system consisting of bile canaliculi of hepatocytes and bile ducts of cholangiocytes is critical to maintain healthy tissue status. This is because hepatocytes produce bile as they functionally mature, and if allowed to remain within the liver tissue can lead to cytotoxicity. In this review, we focus on epithelial tissue morphogenesis in the perinatal period and cholestatic liver diseases caused by abnormal development of the biliary system.
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Affiliation(s)
- Naoki Tanimizu
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, S-1, W-17, Chuo-ku, Sapporo, 060-8556, Japan.
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5
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Belicova L, Repnik U, Delpierre J, Gralinska E, Seifert S, Valenzuela JI, Morales-Navarrete HA, Franke C, Räägel H, Shcherbinina E, Prikazchikova T, Koteliansky V, Vingron M, Kalaidzidis YL, Zatsepin T, Zerial M. Anisotropic expansion of hepatocyte lumina enforced by apical bulkheads. J Cell Biol 2021; 220:212522. [PMID: 34328499 PMCID: PMC8329733 DOI: 10.1083/jcb.202103003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/11/2021] [Accepted: 07/08/2021] [Indexed: 12/20/2022] Open
Abstract
Lumen morphogenesis results from the interplay between molecular pathways and mechanical forces. In several organs, epithelial cells share their apical surfaces to form a tubular lumen. In the liver, however, hepatocytes share the apical surface only between adjacent cells and form narrow lumina that grow anisotropically, generating a 3D network of bile canaliculi (BC). Here, by studying lumenogenesis in differentiating mouse hepatoblasts in vitro, we discovered that adjacent hepatocytes assemble a pattern of specific extensions of the apical membrane traversing the lumen and ensuring its anisotropic expansion. These previously unrecognized structures form a pattern, reminiscent of the bulkheads of boats, also present in the developing and adult liver. Silencing of Rab35 resulted in loss of apical bulkheads and lumen anisotropy, leading to cyst formation. Strikingly, we could reengineer hepatocyte polarity in embryonic liver tissue, converting BC into epithelial tubes. Our results suggest that apical bulkheads are cell-intrinsic anisotropic mechanical elements that determine the elongation of BC during liver tissue morphogenesis.
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Affiliation(s)
- Lenka Belicova
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Urska Repnik
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Julien Delpierre
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Elzbieta Gralinska
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Sarah Seifert
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | | | - Christian Franke
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Helin Räägel
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Nelson Laboratories LLC, Salt Lake City, UT
| | | | | | | | - Martin Vingron
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | - Timofei Zatsepin
- Skolkovo Institute of Science and Technology, Skolkovo, Russia.,Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia
| | - Marino Zerial
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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6
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Jossin Y. Molecular mechanisms of cell polarity in a range of model systems and in migrating neurons. Mol Cell Neurosci 2020; 106:103503. [PMID: 32485296 DOI: 10.1016/j.mcn.2020.103503] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/20/2020] [Accepted: 05/23/2020] [Indexed: 01/09/2023] Open
Abstract
Cell polarity is defined as the asymmetric distribution of cellular components along an axis. Most cells, from the simplest single-cell organisms to highly specialized mammalian cells, are polarized and use similar mechanisms to generate and maintain polarity. Cell polarity is important for cells to migrate, form tissues, and coordinate activities. During development of the mammalian cerebral cortex, cell polarity is essential for neurogenesis and for the migration of newborn but as-yet undifferentiated neurons. These oriented migrations include both the radial migration of excitatory projection neurons and the tangential migration of inhibitory interneurons. In this review, I will first describe the development of the cerebral cortex, as revealed at the cellular level. I will then define the core molecular mechanisms - the Par/Crb/Scrib polarity complexes, small GTPases, the actin and microtubule cytoskeletons, and phosphoinositides/PI3K signaling - that are required for asymmetric cell division, apico-basal and front-rear polarity in model systems, including C elegans zygote, Drosophila embryos and cultured mammalian cells. As I go through each core mechanism I will explain what is known about its importance in radial and tangential migration in the developing mammalian cerebral cortex.
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Affiliation(s)
- Yves Jossin
- Laboratory of Mammalian Development & Cell Biology, Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium.
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7
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Datta A, Yang CR, Limbutara K, Chou CL, Rinschen MM, Raghuram V, Knepper MA. PKA-independent vasopressin signaling in renal collecting duct. FASEB J 2020; 34:6129-6146. [PMID: 32219907 PMCID: PMC9200475 DOI: 10.1096/fj.201902982r] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/13/2020] [Accepted: 02/19/2020] [Indexed: 11/11/2022]
Abstract
Vasopressin regulates renal water excretion by binding to a Gα s-coupled receptor (V2R) in collecting duct cells, resulting in increased water permeability through regulation of the aquaporin-2 (AQP2) water channel. This action is widely accepted to be associated with cAMP-mediated activation of protein kinase A (PKA). Here, we use phosphoproteomics in collecting duct cells in which PKA has been deleted (CRISPR-Cas9) to identify PKA-independent responses to vasopressin. The results show that V2R-mediated vasopressin signaling is predominantly, but not entirely, PKA-dependent. Upregulated sites in PKA-null cells include Ser256 of AQP2, which is critical to regulation of AQP2 trafficking. In addition, phosphorylation changes in the protein kinases Stk39 (SPAK) and Prkci (an atypical PKC) are consistent with PKA-independent regulation of these protein kinases. Target motif analysis of the phosphopeptides increased in PKA-null cells indicates that vasopressin activates one or more members of the AMPK/SNF1-subfamily of basophilic protein kinases. In vitro phosphorylation assays using recombinant, purified SNF1-subfamily kinases confirmed postulated target specificities. Of interest, measured IBMX-dependent cAMP levels were an order of magnitude higher in PKA-null than in PKA-intact cells, indicative of a PKA-dependent feedback mechanism. Overall, the findings support the conclusion that V2-receptor mediated signaling in collecting duct cells is in part PKA-independent.
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Affiliation(s)
- Arnab Datta
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
- Yenepoya Research Center, Yenepoya (Deemed to be University), University Road, Deralakatte, Mangalore 575018, Karnataka, India
| | - Chin-Rang Yang
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Kavee Limbutara
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Chung-Lin Chou
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Markus M. Rinschen
- Department of Chemistry, Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, CA
| | - Viswanathan Raghuram
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Mark A. Knepper
- Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
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8
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Tait CM, Chinnaiya K, Manning E, Murtaza M, Ashton JP, Furley N, Hill CJ, Alves CH, Wijnholds J, Erdmann KS, Furley A, Rashbass P, Das RM, Storey KG, Placzek M. Crumbs2 mediates ventricular layer remodelling to form the spinal cord central canal. PLoS Biol 2020; 18:e3000470. [PMID: 32150534 PMCID: PMC7108746 DOI: 10.1371/journal.pbio.3000470] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 03/31/2020] [Accepted: 02/18/2020] [Indexed: 11/27/2022] Open
Abstract
In the spinal cord, the central canal forms through a poorly understood process termed dorsal collapse that involves attrition and remodelling of pseudostratified ventricular layer (VL) cells. Here, we use mouse and chick models to show that dorsal ventricular layer (dVL) cells adjacent to dorsal midline Nestin(+) radial glia (dmNes+RG) down-regulate apical polarity proteins, including Crumbs2 (CRB2) and delaminate in a stepwise manner; live imaging shows that as one cell delaminates, the next cell ratchets up, the dmNes+RG endfoot ratchets down, and the process repeats. We show that dmNes+RG secrete a factor that promotes loss of cell polarity and delamination. This activity is mimicked by a secreted variant of Crumbs2 (CRB2S) which is specifically expressed by dmNes+RG. In cultured MDCK cells, CRB2S associates with apical membranes and decreases cell cohesion. Analysis of Crb2F/F/Nestin-Cre+/- mice, and targeted reduction of Crb2/CRB2S in slice cultures reveal essential roles for transmembrane CRB2 (CRB2TM) and CRB2S on VL cells and dmNes+RG, respectively. We propose a model in which a CRB2S-CRB2TM interaction promotes the progressive attrition of the dVL without loss of overall VL integrity. This novel mechanism may operate more widely to promote orderly progenitor delamination.
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Affiliation(s)
- Christine M Tait
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Kavitha Chinnaiya
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Elizabeth Manning
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Mariyam Murtaza
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - John-Paul Ashton
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Nicholas Furley
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Chris J Hill
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - C Henrique Alves
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Kai S Erdmann
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Andrew Furley
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Penny Rashbass
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
| | - Raman M Das
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Kate G Storey
- Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Marysia Placzek
- Department of Biomedical Science and Bateson Centre, University of Sheffield, Sheffield, United Kingdom
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9
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Hart M, Zulkipli I, Shrestha RL, Dang D, Conti D, Gul P, Kujawiak I, Draviam VM. MARK2/Par1b kinase present at centrosomes and retraction fibres corrects spindle off-centring induced by actin disassembly. Open Biol 2019; 9:180263. [PMID: 31238822 PMCID: PMC6597755 DOI: 10.1098/rsob.180263] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Tissue maintenance and development requires a directed plane of cell division. While it is clear that the division plane can be determined by retraction fibres that guide spindle movements, the precise molecular components of retraction fibres that control spindle movements remain unclear. We report MARK2/Par1b kinase as a novel component of actin-rich retraction fibres. A kinase-dead mutant of MARK2 reveals MARK2's ability to monitor subcellular actin status during interphase. During mitosis, MARK2's localization at actin-rich retraction fibres, but not the rest of the cortical membrane or centrosome, is dependent on its activity, highlighting a specialized spatial regulation of MARK2. By subtly perturbing the actin cytoskeleton, we reveal MARK2's role in correcting mitotic spindle off-centring induced by actin disassembly. We propose that MARK2 provides a molecular framework to integrate cortical signals and cytoskeletal changes in mitosis and interphase.
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Affiliation(s)
- Madeleine Hart
- 1 School of Biological and Chemical Sciences, Queen Mary University of London , London , UK
| | - Ihsan Zulkipli
- 2 Department of Genetics, University of Cambridge , Cambridge , UK
| | | | - David Dang
- 1 School of Biological and Chemical Sciences, Queen Mary University of London , London , UK.,3 Department of Informatics, King's College, London , London , UK
| | - Duccio Conti
- 1 School of Biological and Chemical Sciences, Queen Mary University of London , London , UK
| | - Parveen Gul
- 1 School of Biological and Chemical Sciences, Queen Mary University of London , London , UK
| | - Izabela Kujawiak
- 2 Department of Genetics, University of Cambridge , Cambridge , UK
| | - Viji M Draviam
- 1 School of Biological and Chemical Sciences, Queen Mary University of London , London , UK
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10
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Zamperone A, Cohen D, Stein M, Viard C, Müsch A. Inhibition of polarity-regulating kinase PAR1b contributes to Helicobacter pylori inflicted DNA Double Strand Breaks in gastric cells. Cell Cycle 2019; 18:299-311. [PMID: 30580666 DOI: 10.1080/15384101.2018.1560121] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The serine/threonine kinase Par1 is a core component of the machinery that sets up polarity in the embryo and regulates cell fate decisions but its role in the homeostasis of adult tissues is poorly understood. Inhibition of Par1 by the bacterium Helicobacter pylori (H. pylori) represents the only established pathology that affects Par1 function in an adult epithelium. Thus, during chronic H. pylori infection of the gastric mucosa Par1 is one of the targets of the non-obligate H.pylori cytotoxic protein and oncogene CagA, which stimulates inflammation and triggers morphological changes, both believed to contribute to the gastric cancer risk imposed by H. pylori infection. Based on Par1's role in cell polarity, it has been speculated that Par1 inhibition affects epithelial polarity. Here we report the unexpected finding that CagA-mediated Par1-inhibition promotes the generation of DNA Double Strand Breaks in primary gastric epithelial cells, which likely contributes to the reported accumulation of mutations in chronically infected mucosal cells. Abbreviations: AGS: human gastric adenocarcinoma cell line; CM: CagA Multimerization (and Par1 binding) domain; H. pylori: Helicobacter pylori; DSB: Double Strand Break; HGECs: human (primary) gastric epithelial cells; IB: immunoblot; IF: immunofluorescence; MOI: Multiplicity of Infection; ROS: reactive oxygen species; Par1: Partitioning Defective 1 kinase; WT: wild type.
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Affiliation(s)
- Andrea Zamperone
- a Department of Developmental & Molecular Biology , Albert Einstein College Medicine , Bronx , NY , USA
| | - David Cohen
- a Department of Developmental & Molecular Biology , Albert Einstein College Medicine , Bronx , NY , USA
| | - Markus Stein
- b Department of Health Sciences , Albany College of Pharmacy and Health Sciences , Albany , NY , USA
| | - Charlotte Viard
- a Department of Developmental & Molecular Biology , Albert Einstein College Medicine , Bronx , NY , USA
| | - Anne Müsch
- a Department of Developmental & Molecular Biology , Albert Einstein College Medicine , Bronx , NY , USA
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11
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Abstract
The cytoskeleton is crucially important for the assembly of cell-cell junctions and the homeostatic regulation of their functions. Junctional proteins act, in turn, as anchors for cytoskeletal filaments, and as regulators of cytoskeletal dynamics and signalling proteins. The cross-talk between junctions and the cytoskeleton is critical for the morphogenesis and physiology of epithelial and other tissues, but is not completely understood. Microtubules are implicated in the delivery of junctional proteins to cell-cell contact sites, in the differentiation and spatial organization of the cytoplasm, and in the stabilization of the barrier and adhesive functions of junctions. Here we focus on the relationships between microtubules and junctions of vertebrate epithelial cells. We highlight recent discoveries on the molecular underpinnings of microtubule-junction interactions, and report new data about the interaction of cingulin and paracingulin with microtubules. We also propose a possible new role of junctions as “molecular sinks” for microtubule-associated signalling proteins.
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Affiliation(s)
- Ekaterina Vasileva
- a Department of Cell Biology, Faculty of Sciences and Institute for Genetics and Genomics in Geneva (iGE3) , University of Geneva , Geneva , Switzerland
| | - Sandra Citi
- a Department of Cell Biology, Faculty of Sciences and Institute for Genetics and Genomics in Geneva (iGE3) , University of Geneva , Geneva , Switzerland
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12
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Zulkipli I, Clark J, Hart M, Shrestha RL, Gul P, Dang D, Kasichiwin T, Kujawiak I, Sastry N, Draviam VM. Spindle rotation in human cells is reliant on a MARK2-mediated equatorial spindle-centering mechanism. J Cell Biol 2018; 217:3057-3070. [PMID: 29941476 PMCID: PMC6122980 DOI: 10.1083/jcb.201804166] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 05/18/2018] [Accepted: 05/24/2018] [Indexed: 12/11/2022] Open
Abstract
Unlike man-made wheels that are centered and rotated via an axle, the mitotic spindle of a human cell is rotated by external cortical pulling mechanisms. Zulkipli et al. identify MARK2’s role in equatorial spindle centering and astral microtubule length, which in turn control spindle rotation. The plane of cell division is defined by the final position of the mitotic spindle. The spindle is pulled and rotated to the correct position by cortical dynein. However, it is unclear how the spindle’s rotational center is maintained and what the consequences of an equatorially off centered spindle are in human cells. We analyzed spindle movements in 100s of cells exposed to protein depletions or drug treatments and uncovered a novel role for MARK2 in maintaining the spindle at the cell’s geometric center. Following MARK2 depletion, spindles glide along the cell cortex, leading to a failure in identifying the correct division plane. Surprisingly, spindle off centering in MARK2-depleted cells is not caused by excessive pull by dynein. We show that MARK2 modulates mitotic microtubule growth and length and that codepleting mitotic centromere-associated protein (MCAK), a microtubule destabilizer, rescues spindle off centering in MARK2-depleted cells. Thus, we provide the first insight into a spindle-centering mechanism needed for proper spindle rotation and, in turn, the correct division plane in human cells.
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Affiliation(s)
- Ihsan Zulkipli
- Department of Genetics, University of Cambridge, Cambridge, England, UK
| | - Joanna Clark
- Department of Genetics, University of Cambridge, Cambridge, England, UK
| | - Madeleine Hart
- School of Biological and Chemical Sciences, Queen Mary University of London, London, England, UK
| | - Roshan L Shrestha
- Department of Genetics, University of Cambridge, Cambridge, England, UK
| | - Parveen Gul
- School of Biological and Chemical Sciences, Queen Mary University of London, London, England, UK
| | - David Dang
- School of Biological and Chemical Sciences, Queen Mary University of London, London, England, UK.,Department of Informatics, King's College, London, England, UK
| | - Tami Kasichiwin
- School of Biological and Chemical Sciences, Queen Mary University of London, London, England, UK
| | - Izabela Kujawiak
- Department of Genetics, University of Cambridge, Cambridge, England, UK
| | - Nishanth Sastry
- Department of Informatics, King's College, London, England, UK
| | - Viji M Draviam
- School of Biological and Chemical Sciences, Queen Mary University of London, London, England, UK .,Department of Genetics, University of Cambridge, Cambridge, England, UK
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13
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Muroyama A, Terwilliger M, Dong B, Suh H, Lechler T. Genetically induced microtubule disruption in the mouse intestine impairs intracellular organization and transport. Mol Biol Cell 2018; 29:1533-1541. [PMID: 29742015 PMCID: PMC6080650 DOI: 10.1091/mbc.e18-01-0057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
In most differentiated cells, microtubules reorganize into noncentrosomal arrays that are cell-type specific. In the columnar absorptive enterocytes of the intestine, microtubules form polarized apical–basal arrays that have been proposed to play multiple roles. However, in vivo testing of these hypotheses has been hampered by a lack of genetic tools to specifically perturb microtubules. Here we analyze mice in which microtubules are disrupted by conditional inducible expression of the microtubule-severing protein spastin. Spastin overexpression resulted in multiple cellular defects, including aberrations in nuclear and organelle positioning and deficient nutrient transport. However, cell shape, adhesion, and polarity remained intact, and mutant mice continued to thrive. Notably, the phenotypes of microtubule disruption are similar to those induced by microtubule disorganization upon loss of CAMSAP3/Nezha. These data demonstrate that enterocyte microtubules have important roles in organelle organization but are not essential for growth under homeostatic conditions.
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Affiliation(s)
- Andrew Muroyama
- Departments of Dermatology and Cell Biology, Duke University, Durham, NC 27708
| | - Michael Terwilliger
- Departments of Dermatology and Cell Biology, Duke University, Durham, NC 27708
| | - Bushu Dong
- Departments of Dermatology and Cell Biology, Duke University, Durham, NC 27708
| | - Harrison Suh
- Departments of Dermatology and Cell Biology, Duke University, Durham, NC 27708
| | - Terry Lechler
- Departments of Dermatology and Cell Biology, Duke University, Durham, NC 27708
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14
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Kreitzer G, Myat MM. Microtubule Motors in Establishment of Epithelial Cell Polarity. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a027896. [PMID: 28264820 DOI: 10.1101/cshperspect.a027896] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Epithelial cells play a key role in insuring physiological homeostasis by acting as a barrier between the outside environment and internal organs. They are also responsible for the vectorial transport of ions and fluid essential to the function of many organs. To accomplish these tasks, epithelial cells must generate an asymmetrically organized plasma membrane comprised of structurally and functionally distinct apical and basolateral membranes. Adherent and occluding junctions, respectively, anchor cells within a layer and prevent lateral diffusion of proteins in the outer leaflet of the plasma membrane and restrict passage of proteins and solutes through intercellular spaces. At a fundamental level, the establishment and maintenance of epithelial polarity requires that signals initiated at cell-substratum and cell-cell adhesions are transmitted appropriately and dynamically to the cytoskeleton, to the membrane-trafficking machinery, and to the regulation of occluding and adherent junctions. Rigorous descriptive and mechanistic studies published over the last 50 years have provided great detail to our understanding of epithelial polarization. Yet still, critical early steps in morphogenesis are not yet fully appreciated. In this review, we discuss how cytoskeletal motor proteins, primarily kinesins, contribute to coordinated modification of microtubule and actin arrays, formation and remodeling of cell adhesions to targeted membrane trafficking, and to initiating the formation and expansion of an apical lumen.
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Affiliation(s)
- Geri Kreitzer
- Department of Pathobiology, Sophie Davis School of Biomedical Education, City College of New York, The City University of New York School of Medicine, New York, New York 10031
| | - Monn Monn Myat
- Department of Biology, Medgar Evers College, Brooklyn, New York 11225.,The Graduate Center, The City University of New York, New York, New York 10016
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15
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Matlin KS, Myllymäki SM, Manninen A. Laminins in Epithelial Cell Polarization: Old Questions in Search of New Answers. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027920. [PMID: 28159878 DOI: 10.1101/cshperspect.a027920] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Laminin, a basement membrane protein discovered in 1979, was shortly thereafter implicated in the polarization of epithelial cells in both mammals and a variety of lower organisms. To transduce a spatial cue to the intrinsic polarization machinery, laminin must polymerize into a dense network that forms the foundation of the basement membrane. Evidence suggests that activation of the small GTPase Rac1 by β1-integrins mobilizes laminin-binding integrins and dystroglycan to consolidate formation of the laminin network and initiate rearrangements of both the actin and microtubule cytoskeleton to help establish the apicobasal axis. A key coordinator of spatial signals from laminin is the serine-threonine kinase Par-1, which is known to affect dystroglycan availability, microtubule and actin organization, and lumen formation. The signaling protein integrin-linked kinase (ILK) may also play a role. Despite significant advances, knowledge of the mechanism by which assembled laminin produces a spatial signal remains fragmentary, and much more research into the complex functions of laminin in polarization and other cellular processes is needed.
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Affiliation(s)
- Karl S Matlin
- Department of Surgery, The University of Chicago, Chicago, Illinois 60637-1470
| | - Satu-Marja Myllymäki
- Biocenter Oulu, Oulu Center for Cell-Matrix Research, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu 90220, Finland
| | - Aki Manninen
- Biocenter Oulu, Oulu Center for Cell-Matrix Research, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu 90220, Finland
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16
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Lázaro-Diéguez F, Müsch A. Cell-cell adhesion accounts for the different orientation of columnar and hepatocytic cell divisions. J Cell Biol 2017; 216:3847-3859. [PMID: 28887437 PMCID: PMC5674875 DOI: 10.1083/jcb.201608065] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 06/01/2017] [Accepted: 08/08/2017] [Indexed: 02/06/2023] Open
Abstract
Mitotic spindle alignment with the basal or substrate-contacting domain ensures that dividing epithelial cells remain in the plane of the monolayer. Spindle orientation with respect to the substratum is established in metaphase coincident with maximal cell rounding, which enables unobstructed spindle rotation. Misaligned metaphase spindles are believed to result in divisions in which one daughter loses contact with the basal lamina. Here we describe a rescue mechanism that drives substrate-parallel spindle alignment of quasi-diagonal metaphase spindles in anaphase. It requires a Rho- and E-cadherin adhesion-dependent, substrate-parallel contractile actin belt at the apex that governs anaphase cell flattening. In contrast to monolayered Madin-Darby canine kidney cells, hepatocytic epithelial cells, which typically feature tilted metaphase spindles, lack this anaphase flattening mechanism and as a consequence maintain their spindle tilt through cytokinesis. This results in out-of-monolayer divisions, which we propose contribute to the stratified organization of hepatocyte cords in vivo.
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Affiliation(s)
- Francisco Lázaro-Diéguez
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Anne Müsch
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY
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17
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Tanimizu N, Mitaka T. Epithelial Morphogenesis during Liver Development. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027862. [PMID: 28213465 DOI: 10.1101/cshperspect.a027862] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Tissue stem/progenitor cells supply multiple types of epithelial cells that eventually acquire specialized functions during organ development. In addition, three-dimensional (3D) tissue structures need to be established for organs to perform their physiological functions. The liver contains two types of epithelial cells, namely, hepatocytes and cholangiocytes, which are derived from hepatoblasts, fetal liver stem/progenitor cells (LPCs), in mid-gestation. Hepatocytes performing many metabolic reactions form cord-like structures, whereas cholangiocytes, biliary epithelial cells, form tubular structures called intrahepatic bile ducts. Analyses for human genetic diseases and mutant mice have identified crucial molecules for liver organogenesis. Functions of those molecules can be examined in in vitro culture systems where LPCs are induced to differentiate into hepatocytes or cholangiocytes. Recent technical advances have revealed 3D epithelial morphogenesis during liver organogenesis. Therefore, the liver is a good model to understand how tissue stem/progenitor cells differentiate and establish 3D tissue architectures during organ development.
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Affiliation(s)
- Naoki Tanimizu
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Chuo-ku, Sapporo 060-8556, Japan
| | - Toshihiro Mitaka
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Chuo-ku, Sapporo 060-8556, Japan
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18
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Ahrari S, Mogharrab N, Navapour L. Interconversion of inactive to active conformation of MARK2: Insights from molecular modeling and molecular dynamics simulation. Arch Biochem Biophys 2017; 630:66-80. [PMID: 28711359 DOI: 10.1016/j.abb.2017.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 07/09/2017] [Accepted: 07/10/2017] [Indexed: 12/18/2022]
Abstract
The Ser/Thr protein kinase MARK2, also known as Par1b, belongs to the highly-conserved family of PAR proteins which regulate cell polarity and partitioning through the animal kingdom. In the current study, inactive and active structures of human MARK2 were constructed by modeling and molecular dynamics simulation, based on available incomplete crystal structures in Protein Data Bank, to investigate local structural changes through which MARK2 switches from inactive to active state. None of the MARK2 wild type inactive crystal structures represent the position of activation segment. So, the contribution of this loop to the formation of inactive state is not clear. In the modeled structure of inactive MARK2, activation segment occludes the enzyme active site and assumes a relatively stable position. We also presented a detailed description of the major structural changes occur through the activation process and proposed a framework on how these deviations might be affected by the phosphorylation of Thr208 or existence of the UBA domain. Inspection of protein active state in the presence of Mg-ATP, demonstrated the precise arrangement of the various parts of enzyme around Mg-ATP and the importance of their stability in localization of the resulting complex. The results also confirmed the alleged mild auto-inhibitory role of the UBA domain and suggested a reason for the necessity of this role, based on structural similarities to other related kinases.
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Affiliation(s)
- Sajjad Ahrari
- Biophysics and Computational Biology Laboratory (BCBL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
| | - Navid Mogharrab
- Biophysics and Computational Biology Laboratory (BCBL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran.
| | - Leila Navapour
- Biophysics and Computational Biology Laboratory (BCBL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
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19
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Pescio LG, Santacreu BJ, Lopez VG, Paván CH, Romero DJ, Favale NO, Sterin-Speziale NB. Changes in ceramide metabolism are essential in Madin-Darby canine kidney cell differentiation. J Lipid Res 2017; 58:1428-1438. [PMID: 28515139 DOI: 10.1194/jlr.m076349] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 05/16/2017] [Indexed: 01/03/2023] Open
Abstract
Ceramides (Cers) and complex sphingolipids with defined acyl chain lengths play important roles in numerous cell processes. Six Cer synthase (CerS) isoenzymes (CerS1-6) are the key enzymes responsible for the production of the diversity of molecular species. In this study, we investigated the changes in sphingolipid metabolism during the differentiation of Madin-Darby canine kidney (MDCK) cells. By MALDI TOF TOF MS, we analyzed the molecular species of Cer, glucosylceramide (GlcCer), lactosylceramide (LacCer), and SM in nondifferentiated and differentiated cells (cultured under hypertonicity). The molecular species detected were the same, but cells subjected to hypertonicity presented higher levels of C24:1 Cer, C24:1 GlcCer, C24:1 SM, and C16:0 LacCer. Consistently with the molecular species, MDCK cells expressed CerS2, CerS4, and CerS6, but with no differences during cell differentiation. We next evaluated the different synthesis pathways with sphingolipid inhibitors and found that cells subjected to hypertonicity in the presence of amitriptyline, an inhibitor of acid sphingomyelinase, showed decreased radiolabeled incorporation in LacCer and cells did not develop a mature apical membrane. These results suggest that hypertonicity induces the endolysosomal degradation of SM, generating the Cer used as substrate for the synthesis of specific molecular species of glycosphingolipids that are essential for MDCK cell differentiation.
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Affiliation(s)
- Lucila Gisele Pescio
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Bruno Jaime Santacreu
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Vanina Gisela Lopez
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina
| | - Carlos Humberto Paván
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina
| | - Daniela Judith Romero
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina
| | - Nicolás Octavio Favale
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Cátedra de Biología Celular y Molecular, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Buenos Aires, Argentina
| | - Norma Beatriz Sterin-Speziale
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Laboratorio Nacional de Investigación y Servicios de Péptidos y Proteínas - Espectrometría de Masa (LANAIS PROEM), Buenos Aires, Argentina.
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20
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Honda H. The world of epithelial sheets. Dev Growth Differ 2017; 59:306-316. [PMID: 28503767 DOI: 10.1111/dgd.12350] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 03/19/2017] [Accepted: 03/20/2017] [Indexed: 12/21/2022]
Abstract
An epithelium is a layer of closely connected cells covering the body or lining a body cavity. In this review, several fundamental questions are addressed regarding the epithelium. (i) While an epithelium functions as barrier against the external environment, how is barrier function maintained during its construction? (ii) What determines the apical and basal sides of epithelial layer? (iii) Is there any relationship between the apical side of the epithelium and the apical membrane of an epithelial cell? (iv) Why are hepatocytes (liver cells) called epithelial, even though they differ completely from column-like shape of typical epithelial cells? Keeping these questions in mind, multiple shapes of epithelia were considered, extracting a few of their elemental processes, and constructing a virtual world of epithelia by combining them. Epithelial cells were also classified into several types based on the number of apical domains of each cell. In addition, an intracellular organelle was introduced within epithelial cells, the vacuolar apical compartment (VAC), which is produced within epithelial cells surrounded by external cell matrix (ECM). The VAC interacts with areas of cell-cell contact of the cell surface membrane and is converted to apical membrane. The properties of VACs enable us to answer the initial questions posed above. Finally, the genetic and molecular mechanisms of epithelial morphogenesis are discussed.
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Affiliation(s)
- Hisao Honda
- Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.,Laboratory for Morphogenetic Signaling, RIKEN Center for Developmental Biology, Kobe, 650-0047, Japan
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21
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Lara-Diaz VJ, Castilla-Cortazar I, Martín-Estal I, García-Magariño M, Aguirre GA, Puche JE, de la Garza RG, Morales LA, Muñoz U. IGF-1 modulates gene expression of proteins involved in inflammation, cytoskeleton, and liver architecture. J Physiol Biochem 2017; 73:245-258. [PMID: 28124277 PMCID: PMC5399066 DOI: 10.1007/s13105-016-0545-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 12/16/2016] [Indexed: 12/22/2022]
Abstract
Even though the liver synthesizes most of circulating IGF-1, it lacks its receptor under physiological conditions. However, according to previous studies, a damaged liver expresses the receptor. For this reason, herein, we examine hepatic histology and expression of genes encoding proteins of the cytoskeleton, extracellular matrix, and cell-cell molecules and inflammation-related proteins. A partial IGF-1 deficiency murine model was used to investigate IGF-1's effects on liver by comparing wild-type controls, heterozygous igf1+/-, and heterozygous mice treated with IGF-1 for 10 days. Histology, microarray for mRNA gene expression, RT-qPCR, and lipid peroxidation were assessed. Microarray analyses revealed significant underexpression of igf1 in heterozygous mice compared to control mice, restoring normal liver expression after treatment, which then normalized its circulating levels. IGF-1 receptor mRNA was overexpressed in Hz mice liver, while treated mice displayed a similar expression to that of the controls. Heterozygous mice showed overexpression of several genes encoding proteins related to inflammatory and acute-phase proteins and underexpression or overexpression of genes which coded for extracellular matrix, cytoskeleton, and cell junction components. Histology revealed an altered hepatic architecture. In addition, liver oxidative damage was found increased in the heterozygous group. The mere IGF-1 partial deficiency is associated with relevant alterations of the hepatic architecture and expression of genes involved in cytoskeleton, hepatocyte polarity, cell junctions, and extracellular matrix proteins. Moreover, it induces hepatic expression of the IGF-1 receptor and elevated acute-phase and inflammation mediators, which all resulted in liver oxidative damage.
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Affiliation(s)
- V J Lara-Diaz
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - I Castilla-Cortazar
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico. .,Fundacion de Investigacion HM Hospitales, Madrid, Spain.
| | - I Martín-Estal
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - M García-Magariño
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - G A Aguirre
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - J E Puche
- Department of Medical Physiology, School of Medicine, Universidad San Pablo-CEU, Madrid, Spain
| | - R G de la Garza
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - L A Morales
- Escuela de Medicina, Tecnologico de Monterrey, Avenida Morones Prieto No. 3000 Pte. Col. Los Doctores, 64710, Monterrey, Nuevo León, Mexico
| | - U Muñoz
- Department of Medical Physiology, School of Medicine, Universidad San Pablo-CEU, Madrid, Spain
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22
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McRae R, Lapierre LA, Manning EH, Goldenring JR. Rab11-FIP1 phosphorylation by MARK2 regulates polarity in MDCK cells. CELLULAR LOGISTICS 2017; 7:e1271498. [PMID: 28396819 DOI: 10.1080/21592799.2016.1271498] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/30/2016] [Accepted: 12/06/2016] [Indexed: 10/20/2022]
Abstract
MARK2/Par1b/EMK1, a serine/threonine kinase, is required for correct apical/basolateral membrane polarization in epithelial cells. However, the specific substrates mediating MARK2 action are less well understood. We have now found that MARK2 phosphorylates Rab11-FIP1B/C at serine 234 in a consensus site similar to that previously identified in Rab11-FIP2. In MDCK cells undergoing repolarization after a calcium switch, antibodies specific for pS234-Rab11-FIP1 or pS227-Rab11-FIP2 demonstrate that the spatial and temporal activation of Rab11-FIP1 phosphorylation is distinct from that for Rab11-FIP2. Phosphorylation of Rab11-FIP1 persists through calcium switch and remains high after polarity has been reestablished whereas FIP2 phosphorylation is highest early in reestablishment of polarity but significantly reduced once polarity has been re-established. MARK2 colocalized with FIP1B/C/D and p(S234)-FIP1 in vivo. Overexpression of GFP-Rab11-FIP1C wildtype or non-phosphorylatable GFP-Rab11-FIP1C(S234A) induced two significant phenotypes following calcium switch. Overexpression of FIP1C wildtype and FIP1C(S234A) caused a psuedo-stratification of cells in early time points following calcium switch. At later time points most prominently observed in cells expressing FIP1C(S234A) a significant lateral lumen phenotype was observed, where F-actin-rich lateral lumens appeared demarcated by a ring of ZO1 and also containing ezrin, syntaxin 3 and podocalyxin. In contrast, p120 and E-Cadherin were excluded from the new apical surface at the lateral lumens and now localized to the new lateral surface oriented toward the media. GFP-FIP1C(S234A) localized to membranes deep to the lateral lumens, and immunostaining demonstrated the reorientation of the centrosome and the Golgi apparatus toward the lateral lumen. These results suggest that both Rab11-FIP1B/C and Rab11-FIP2 serve as critical substrates mediating aspects of MARK2 regulation of epithelial polarity.
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Affiliation(s)
- Rebecca McRae
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Lynne A Lapierre
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA; Nashville VA Medical Center, Nashville, TN, USA
| | - Elizabeth H Manning
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA; Nashville VA Medical Center, Nashville, TN, USA
| | - James R Goldenring
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Cell & Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA; Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, TN, USA; Nashville VA Medical Center, Nashville, TN, USA; Vanderbilt Ingram Cancer Center, Nashville, TN, USA
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23
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Schmidt A, Lv Z, Großhans J. ELMO and Sponge specify subapical restriction of Canoe and formation of the subapical domain in early Drosophila embryos. Development 2017; 145:dev.157909. [DOI: 10.1242/dev.157909] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 12/18/2017] [Indexed: 01/06/2023]
Abstract
Canoe/Afadin and the GTPase Rap1 specify the subapical domain during cellularization in Drosophila embryos. The timing of domain formation is unclear. The subapical domain may gradually mature or emerge synchronously with basal and lateral domain. The mechanism for activation of Rap1 by potential guanyl nucleotide exchange factors (GEF) or GTPase activating proteins (GAP) is unknown. Here, we retraced the emergence of the subapical domain at the onset of cellularization by in vivo imaging with CanoeYFP in comparison to the lateral and basal markers, ScribbledGFP and CherrySlam. CanoeYFP accumulates at a subapical position at about the same time as the lateral marker ScribbledGFP but a few minutes prior to basal CherrySlam. Furthermore, we show that the unconventional GEF complex ELMO-Sponge is subapically enriched and is required for subapical restriction of Canoe. The localization dynamics of ELMO-Sponge suggests a patterning mechanism for positioning the subapical region adjacent to the apical region. While marking the disc-like apical regions before cellularization, ELMO-Sponge redistributes to a ring-like pattern surrounding the apical region at the onset of cellularization.
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Affiliation(s)
- Anja Schmidt
- Institute for Developmental Biochemistry, University of Göttingen, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
| | - Zhiyi Lv
- Institute for Developmental Biochemistry, University of Göttingen, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
| | - Jörg Großhans
- Institute for Developmental Biochemistry, University of Göttingen, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
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24
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Tanimizu N, Mitaka T. Morphogenesis of liver epithelial cells. Hepatol Res 2016; 46:964-76. [PMID: 26785307 DOI: 10.1111/hepr.12654] [Citation(s) in RCA: 146] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 01/12/2016] [Accepted: 01/14/2016] [Indexed: 12/17/2022]
Abstract
The mammalian liver is a physiologically important organ performing various types of metabolism, producing serum proteins, detoxifying bilirubin and ammonia, and protecting the body from infection. Those physiological functions are achieved with the 3D tissue architecture of liver epithelial cells. The liver contains two types of epithelial cells, namely, hepatocytes and cholangiocytes. They split from hepatoblasts (embryonic liver stem cells) in mid-gestation and differentiate into structurally and functionally mature cells. Analyses of mutant mice showing abnormal liver organogenesis have identified genes involved in liver development. In vitro culture systems have been used to examine the mechanism in which each molecule or signaling pathway regulates the morphogenesis and functional differentiation of hepatocytes and cholangiocytes. In addition, liver epithelial cells as well as mesenchymal, sinusoidal endothelial and hematopoietic cells can be purified from developing livers, which enables us to perform genome-wide screening to identify novel genes regulating epithelial morphogenesis in the liver. By combining these in vivo and in vitro systems, the liver could be a unique and suitable model for revealing a principle, governing epithelial morphogenesis. In this review, we summarize recent progress in the understanding of the development of liver epithelial tissue structures.
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Affiliation(s)
- Naoki Tanimizu
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Toshihiro Mitaka
- Department of Tissue Development and Regeneration, Research Institute for Frontier Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
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25
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Gallegos LL, Ng MR, Sowa ME, Selfors LM, White A, Zervantonakis IK, Singh P, Dhakal S, Harper JW, Brugge JS. A protein interaction map for cell-cell adhesion regulators identifies DUSP23 as a novel phosphatase for β-catenin. Sci Rep 2016; 6:27114. [PMID: 27255161 PMCID: PMC4891818 DOI: 10.1038/srep27114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 05/10/2016] [Indexed: 01/13/2023] Open
Abstract
Cell-cell adhesion is central to morphogenesis and maintenance of epithelial cell state. We previously identified 27 candidate cell-cell adhesion regulatory proteins (CCARPs) whose down-regulation disrupts epithelial cell-cell adhesion during collective migration. Using a protein interaction mapping strategy, we found that 18 CCARPs link to core components of adherens junctions or desmosomes. We further mapped linkages between the CCARPs and other known cell-cell adhesion proteins, including hits from recent screens uncovering novel components of E-cadherin adhesions. Mechanistic studies of one novel CCARP which links to multiple cell-cell adhesion proteins, the phosphatase DUSP23, revealed that it promotes dephosphorylation of β-catenin at Tyr 142 and enhances the interaction between α- and β-catenin. DUSP23 knockdown specifically diminished adhesion to E-cadherin without altering adhesion to fibronectin matrix proteins. Furthermore, DUSP23 knockdown produced “zipper-like” cell-cell adhesions, caused defects in transmission of polarization cues, and reduced coordination during collective migration. Thus, this study identifies multiple novel connections between proteins that regulate cell-cell interactions and provides evidence for a previously unrecognized role for DUSP23 in regulating E-cadherin adherens junctions through promoting the dephosphorylation of β-catenin.
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Affiliation(s)
| | - Mei Rosa Ng
- Cell Biology, Harvard Med School, Boston, MA, USA
| | | | | | - Anne White
- Cell Biology, Harvard Med School, Boston, MA, USA
| | | | - Pragya Singh
- Cell Biology, Harvard Med School, Boston, MA, USA
| | - Sabin Dhakal
- Cell Biology, Harvard Med School, Boston, MA, USA
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Cearns MD, Escuin S, Alexandre P, Greene NDE, Copp AJ. Microtubules, polarity and vertebrate neural tube morphogenesis. J Anat 2016; 229:63-74. [PMID: 27025884 DOI: 10.1111/joa.12468] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/17/2016] [Indexed: 12/20/2022] Open
Abstract
Microtubules (MTs) are key cellular components, long known to participate in morphogenetic events that shape the developing embryo. However, the links between the cellular functions of MTs, their effects on cell shape and polarity, and their role in large-scale morphogenesis remain poorly understood. Here, these relationships were examined with respect to two strategies for generating the vertebrate neural tube: bending and closure of the mammalian neural plate; and cavitation of the teleost neural rod. The latter process has been compared with 'secondary' neurulation that generates the caudal spinal cord in mammals. MTs align along the apico-basal axis of the mammalian neuroepithelium early in neural tube closure, participating functionally in interkinetic nuclear migration, which indirectly impacts on cell shape. Whether MTs play other functional roles in mammalian neurulation remains unclear. In the zebrafish, MTs are important for defining the neural rod midline prior to its cavitation, both by localizing apical proteins at the tissue midline and by orienting cell division through a mirror-symmetric MT apparatus that helps to further define the medial localization of apical polarity proteins. Par proteins have been implicated in centrosome positioning in neuroepithelia as well as in the control of polarized morphogenetic movements in the neural rod. Understanding of MT functions during early nervous system development has so far been limited, partly by techniques that fail to distinguish 'cause' from 'effect'. Future developments will likely rely on novel ways to selectively impair MT function in order to investigate the roles they play.
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Affiliation(s)
- Michael D Cearns
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, UK
| | - Sarah Escuin
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, UK
| | - Paula Alexandre
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, UK
| | - Nicholas D E Greene
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, UK
| | - Andrew J Copp
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, UK
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Bizet AA, Becker-Heck A, Ryan R, Weber K, Filhol E, Krug P, Halbritter J, Delous M, Lasbennes MC, Linghu B, Oakeley EJ, Zarhrate M, Nitschké P, Garfa-Traore M, Serluca F, Yang F, Bouwmeester T, Pinson L, Cassuto E, Dubot P, Elshakhs NAS, Sahel JA, Salomon R, Drummond IA, Gubler MC, Antignac C, Chibout S, Szustakowski JD, Hildebrandt F, Lorentzen E, Sailer AW, Benmerah A, Saint-Mezard P, Saunier S. Mutations in TRAF3IP1/IFT54 reveal a new role for IFT proteins in microtubule stabilization. Nat Commun 2015; 6:8666. [PMID: 26487268 PMCID: PMC4617596 DOI: 10.1038/ncomms9666] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 09/17/2015] [Indexed: 01/20/2023] Open
Abstract
Ciliopathies are a large group of clinically and genetically heterogeneous disorders caused by defects in primary cilia. Here we identified mutations in TRAF3IP1 (TNF Receptor-Associated Factor Interacting Protein 1) in eight patients from five families with nephronophthisis (NPH) and retinal degeneration, two of the most common manifestations of ciliopathies. TRAF3IP1 encodes IFT54, a subunit of the IFT-B complex required for ciliogenesis. The identified mutations result in mild ciliary defects in patients but also reveal an unexpected role of IFT54 as a negative regulator of microtubule stability via MAP4 (microtubule-associated protein 4). Microtubule defects are associated with altered epithelialization/polarity in renal cells and with pronephric cysts and microphthalmia in zebrafish embryos. Our findings highlight the regulation of cytoplasmic microtubule dynamics as a role of the IFT54 protein beyond the cilium, contributing to the development of NPH-related ciliopathies.
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Affiliation(s)
- Albane A. Bizet
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | - Anita Becker-Heck
- Novartis Institutes for Biomedical Research, Basel CH-4002, Switzerland
| | - Rebecca Ryan
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | - Kristina Weber
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany
| | - Emilie Filhol
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | - Pauline Krug
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | - Jan Halbritter
- Division of Nephrology, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
- Division of Nephrology, Department of Internal Medicine, University Clinic Leipzig, 04103 Leipzig, Germany
| | - Marion Delous
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | | | - Bolan Linghu
- Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA
| | - Edward J. Oakeley
- Novartis Institutes for Biomedical Research, Basel CH-4002, Switzerland
| | - Mohammed Zarhrate
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
- Inserm UMR-1163, Genomic Core Facility, 75015 Paris, France
| | - Patrick Nitschké
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Bioinformatics Core Facility, 75015 Paris, France
| | - Meriem Garfa-Traore
- Cell Imaging Platform, INSERM US24 Structure Fédérative de recherche Necker, Paris Descartes Sorbonne Paris Cité University, 75015 Paris, France
| | - Fabrizio Serluca
- Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA
| | - Fan Yang
- Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139, USA
| | - Tewis Bouwmeester
- Novartis Institutes for Biomedical Research, Basel CH-4002, Switzerland
| | - Lucile Pinson
- Department of Medical Genetic, Arnaud de Villeneuve University Health Center, 34090 Montpellier, France
| | - Elisabeth Cassuto
- Nephrology department, L'Archet II Hospital, Nice University Health Center, 06202 Nice, France
| | - Philippe Dubot
- Hemodialysis-Nephrology Department, William Morey Hospital, 71321 Chalon-sur-Saône, France
| | - Neveen A. Soliman Elshakhs
- Department of Pediatrics, Center of Pediatric Nephrology and Transplantation, Cairo University, Egyptian Group for Orphan Renal Diseases, 11956 Cairo, Egypt
| | - José A. Sahel
- INSERM U968, CNRS UMR 7210; Sorbonne Universités, Université Pierre et Marie Curie, UMR S968, Institut de la vision, 75012 Paris, France
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, INSERM, Direction de l'Hospitalisation et de l'Organisation des Soins, Centre d'Investigation Clinique 1423, 75012 Paris, France
| | - Rémi Salomon
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
- Assistance Publique—Hôpitaux de Paris, Pediatric Nephrologic department, Necker-Enfants Malades Hospital, 75015 Paris, France
| | - Iain A. Drummond
- Nephrology Division, Massachusetts General Hospital, Charlestown, Massachusetts 02114, USA
- Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Marie-Claire Gubler
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | - Corinne Antignac
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
- Assistance Publique-Hôpitaux de Paris, Department of Genetics, Necker-Enfants Malades Hospital, 75015 Paris, France
| | - Salahdine Chibout
- Novartis Institutes for Biomedical Research, Basel CH-4002, Switzerland
| | | | - Friedhelm Hildebrandt
- Division of Nephrology, Department of Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Esben Lorentzen
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany
| | - Andreas W. Sailer
- Novartis Institutes for Biomedical Research, Basel CH-4002, Switzerland
| | - Alexandre Benmerah
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
| | | | - Sophie Saunier
- Inserm UMR-1163, Laboratory of Hereditary Kidney Diseases, 75015 Paris, France
- Paris Descartes Sorbonne Paris Cité University, Imagine Institute, 75015 Paris, France
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A Par-1-Par-3-Centrosome Cell Polarity Pathway and Its Tuning for Isotropic Cell Adhesion. Curr Biol 2015; 25:2701-8. [PMID: 26455305 DOI: 10.1016/j.cub.2015.08.063] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 07/08/2015] [Accepted: 08/28/2015] [Indexed: 02/02/2023]
Abstract
To form regulated barriers between body compartments, epithelial cells polarize into apical and basolateral domains and assemble adherens junctions (AJs). Despite close links with polarity networks that generate single polarized domains, AJs distribute isotropically around the cell circumference for adhesion with all neighboring cells [1-3]. How AJs avoid the influence of polarity networks to maintain their isotropy has been unclear. In established epithelia, trans cadherin interactions could maintain AJ isotropy [4], but AJs are dynamic during epithelial development and remodeling [5, 6], and thus specific mechanisms may control their isotropy. In Drosophila, aPKC prevents hyper-polarization of junctions as epithelia develop from cellularization to gastrulation [7]. Here, we show that aPKC does so by inhibiting a positive feedback loop between Bazooka (Baz)/Par-3, a junctional organizer [5, 8-10], and centrosomes. Without aPKC, Baz and centrosomes lose their isotropic distributions and recruit each other to single plasma membrane (PM) domains. Surprisingly, our loss- and gain-of-function analyses show that the Baz-centrosome positive feedback loop is driven by Par-1, a kinase known to phosphorylate Baz and inhibit its basolateral localization [8, 11, 12]. We find that Par-1 promotes the positive feedback loop through both centrosome microtubule effects and Baz phosphorylation. Normally, aPKC attenuates the circuit by expelling Par-1 from the apical domain at gastrulation. The combination of local activation and global inhibition is a common polarization strategy [13-16]. Par-1 seems to couple both effects for a potent Baz polarization mechanism that is regulated for the isotropy of Baz and AJs around the cell circumference.
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Gissen P, Arias IM. Structural and functional hepatocyte polarity and liver disease. J Hepatol 2015; 63:1023-37. [PMID: 26116792 PMCID: PMC4582071 DOI: 10.1016/j.jhep.2015.06.015] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 06/14/2015] [Accepted: 06/15/2015] [Indexed: 02/08/2023]
Abstract
Hepatocytes form a crucially important cell layer that separates sinusoidal blood from the canalicular bile. They have a uniquely organized polarity with a basal membrane facing liver sinusoidal endothelial cells, while one or more apical poles can contribute to several bile canaliculi jointly with the directly opposing hepatocytes. Establishment and maintenance of hepatocyte polarity is essential for many functions of hepatocytes and requires carefully orchestrated cooperation between cell adhesion molecules, cell junctions, cytoskeleton, extracellular matrix and intracellular trafficking machinery. The process of hepatocyte polarization requires energy and, if abnormal, may result in severe liver disease. A number of inherited disorders affecting tight junction and intracellular trafficking proteins have been described and demonstrate clinical and pathophysiological features overlapping those of the genetic cholestatic liver diseases caused by defects in canalicular ABC transporters. Thus both structural and functional components contribute to the final hepatocyte polarity phenotype. Many acquired liver diseases target factors that determine hepatocyte polarity, such as junctional proteins. Hepatocyte depolarization frequently occurs but is rarely recognized because hematoxylin-eosin staining does not identify the bile canaliculus. However, the molecular mechanisms underlying these defects are not well understood. Here we aim to provide an update on the key factors determining hepatocyte polarity and how it is affected in inherited and acquired diseases.
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Affiliation(s)
- Paul Gissen
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; UCL Institute of Child Health, London, UK; Great Ormond Street Hospital, London, UK.
| | - Irwin M Arias
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, United States
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Singh B, Bogatcheva G, Starchenko A, Sinnaeve J, Lapierre LA, Williams JA, Goldenring JR, Coffey RJ. Induction of lateral lumens through disruption of a monoleucine-based basolateral-sorting motif in betacellulin. J Cell Sci 2015; 128:3444-55. [PMID: 26272915 DOI: 10.1242/jcs.170852] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 08/05/2015] [Indexed: 12/18/2022] Open
Abstract
Directed delivery of EGF receptor (EGFR) ligands to the apical or basolateral surface is a crucial regulatory step in the initiation of EGFR signaling in polarized epithelial cells. Herein, we show that the EGFR ligand betacellulin (BTC) is preferentially sorted to the basolateral surface of polarized MDCK cells. By using sequential truncations and site-directed mutagenesis within the BTC cytoplasmic domain, combined with selective cell-surface biotinylation and immunofluorescence, we have uncovered a monoleucine-based basolateral-sorting motif (EExxxL, specifically (156)EEMETL(161)). Disruption of this sorting motif led to equivalent apical and basolateral localization of BTC. Unlike other EGFR ligands, BTC mistrafficking induced formation of lateral lumens in polarized MDCK cells, and this process was significantly attenuated by inhibition of EGFR. Additionally, expression of a cancer-associated somatic BTC mutation (E156K) led to BTC mistrafficking and induced lateral lumens in MDCK cells. Overexpression of BTC, especially mistrafficking forms, increased the growth of MDCK cells. These results uncover a unique role for BTC mistrafficking in promoting epithelial reorganization.
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Affiliation(s)
- Bhuminder Singh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Galina Bogatcheva
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Alina Starchenko
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Justine Sinnaeve
- Interdisciplinary Graduate Program, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Lynne A Lapierre
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Janice A Williams
- Vanderbilt Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Cell Imaging Shared Resource, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - James R Goldenring
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Veteran Affairs Medical Center, Nashville, TN 37232, USA
| | - Robert J Coffey
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN 37232, USA Department of Veteran Affairs Medical Center, Nashville, TN 37232, USA
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31
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Overeem AW, Bryant DM, van IJzendoorn SC. Mechanisms of apical–basal axis orientation and epithelial lumen positioning. Trends Cell Biol 2015; 25:476-85. [DOI: 10.1016/j.tcb.2015.04.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 03/24/2015] [Accepted: 04/06/2015] [Indexed: 12/17/2022]
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Swisa A, Granot Z, Tamarina N, Sayers S, Bardeesy N, Philipson L, Hodson DJ, Wikstrom JD, Rutter GA, Leibowitz G, Glaser B, Dor Y. Loss of Liver Kinase B1 (LKB1) in Beta Cells Enhances Glucose-stimulated Insulin Secretion Despite Profound Mitochondrial Defects. J Biol Chem 2015; 290:20934-20946. [PMID: 26139601 PMCID: PMC4543653 DOI: 10.1074/jbc.m115.639237] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Indexed: 12/25/2022] Open
Abstract
The tumor suppressor liver kinase B1 (LKB1) is an important regulator of pancreatic β cell biology. LKB1-dependent phosphorylation of distinct AMPK (adenosine monophosphate-activated protein kinase) family members determines proper β cell polarity and restricts β cell size, total β cell mass, and glucose-stimulated insulin secretion (GSIS). However, the full spectrum of LKB1 effects and the mechanisms involved in the secretory phenotype remain incompletely understood. We report here that in the absence of LKB1 in β cells, GSIS is dramatically and persistently improved. The enhancement is seen both in vivo and in vitro and cannot be explained by altered cell polarity, increased β cell number, or increased insulin content. Increased secretion does require membrane depolarization and calcium influx but appears to rely mostly on a distal step in the secretion pathway. Surprisingly, enhanced GSIS is seen despite profound defects in mitochondrial structure and function in LKB1-deficient β cells, expected to greatly diminish insulin secretion via the classic triggering pathway. Thus LKB1 is essential for mitochondrial homeostasis in β cells and in parallel is a powerful negative regulator of insulin secretion. This study shows that β cells can be manipulated to enhance GSIS to supra-normal levels even in the face of defective mitochondria and without deterioration over months.
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Affiliation(s)
- Avital Swisa
- Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel
| | - Zvi Granot
- Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel
| | - Natalia Tamarina
- Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - Sophie Sayers
- Section of Cell Biology and Functional Genomics, Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Imperial College London, SW7 2AZ, London, United Kingdom
| | - Nabeel Bardeesy
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, Massachusetts 02114
| | - Louis Philipson
- Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - David J Hodson
- Section of Cell Biology and Functional Genomics, Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Imperial College London, SW7 2AZ, London, United Kingdom
| | - Jakob D Wikstrom
- Endocrinology and Metabolism Service, Department of Internal Medicine, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel; Unit of Dermatology and Venereology, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, 171 77 Stockholm, Sweden
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Imperial College London, SW7 2AZ, London, United Kingdom
| | - Gil Leibowitz
- Endocrinology and Metabolism Service, Department of Internal Medicine, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel
| | - Benjamin Glaser
- Endocrinology and Metabolism Service, Department of Internal Medicine, Hadassah-Hebrew University Medical Center, Jerusalem 91120, Israel
| | - Yuval Dor
- Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
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Manninen A. Epithelial polarity – Generating and integrating signals from the ECM with integrins. Exp Cell Res 2015; 334:337-49. [DOI: 10.1016/j.yexcr.2015.01.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 01/20/2023]
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Hayashi K, Suzuki A, Ohno S. A novel function of the cell polarity-regulating kinase PAR-1/MARK in dendritic spines. BIOARCHITECTURE 2014; 1:261-266. [PMID: 22545177 DOI: 10.4161/bioa.1.6.19199] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dendritic spines are postsynaptic structures that receive excitatory synaptic signals from presynaptic terminals in neurons. Because the morphology of spines has been considered to be a crucial factor for the efficiency of synaptic transmission, understanding the mechanisms regulating their morphology is important for neuroscience. Actin filaments and their regulatory proteins are known to actively maintain spine morphology; recent studies have also shown an essential role of microtubules (MTs). Live imaging of the plus-ends of MTs in mature neurons revealed that MTs stochastically enter spines and mediate accumulation of p140Cap, which regulates reorganization of actin filaments. However, the molecular mechanism by which MT dynamics is controlled has remained largely unknown. A cell polarity-regulating serine/threonine kinase, partitioning-defective 1 (PAR-1), phosphorylates classical MAPs and inhibits their binding to MTs. Because the interaction of MAPs with MTs can decrease MT dynamic instability, PAR-1 is supposed to activate MT dynamics through its MAP/MT affinity-regulating kinase (MARK) activity, although there is not yet any direct evidence for this. Here, we review recent findings on the localization of PAR-1b in the dendrites of mouse hippocampal neurons, and its novel function in the maintenance of mature spine morphology by regulating MT dynamics.
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Affiliation(s)
- Kenji Hayashi
- Department of Molecular Biology; Yokohama City University Graduate School of Medical Science; Yokohama, Japan
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Takano K, Kojima T, Sawada N, Himi T. Role of tight junctions in signal transduction: an update. EXCLI JOURNAL 2014; 13:1145-62. [PMID: 26417329 PMCID: PMC4464418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/14/2014] [Indexed: 11/18/2022]
Abstract
Tight junctions (TJs), which are the most apically located of the intercellular junctional complexes, have a barrier function and a fence function. Recent studies show that they also participate in signal transduction mechanisms. TJs are modulated by intracellular signaling pathways including protein kinase C, mitogen-activated protein kinase, and NF-ϰB, to affect the epithelial barrier function in response to diverse stimuli. TJs are also regulated by various cytokines, growth factors, and hormones via signaling pathways. To investigate the regulation of TJ molecules via signaling pathways in human epithelial cells under normal and pathological conditions, we established a novel model of human telomerase reverse transcriptase-transfected human epithelial cells. In this review, we describe the recent progress in our understanding of the role of TJs for signal transduction under normal conditions in upper airway epithelium, pancreatic duct epithelial cells, hepatocytes, and endometrial epithelial cells, and in pathological conditions including cancer and infection.
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Affiliation(s)
- Kenichi Takano
- Department of Otolaryngology,*To whom correspondence should be addressed: Kenichi Takano, Department of Otolaryngology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo 060-8543, Japan, Phone +81-11-688-9655, Fax +81-11-615-5405, E-mail:
| | | | - Norimasa Sawada
- Pathology, Sapporo Medical University School of Medicine, Sapporo, Japan
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Ahrari S, Mogharrab N. Effects of T208E activating mutation on MARK2 protein structure and dynamics: Modeling and simulation. MOLECULAR BIOLOGY RESEARCH COMMUNICATIONS 2014; 3:149-164. [PMID: 27843979 PMCID: PMC5019223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Microtubule Affinity-Regulating Kinase 2 (MARK2) protein has a substantial role in regulation of vital cellular processes like induction of polarity, regulation of cell junctions, cytoskeleton structure and cell differentiation. The abnormal function of this protein has been associated with a number of pathological conditions like Alzheimer disease, autism, several carcinomas and development of virulent effects of Helicobacter pyloriββαβββ.
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Affiliation(s)
- Sajjad Ahrari
- Biophysics and Computational Biology Laboratory, Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
| | - Navid Mogharrab
- Biophysics and Computational Biology Laboratory, Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran,Institute of Biotechnology, Shiraz University, Shiraz, Iran,Address for correspondence: Biophysics and Computational Biology Laboratory, Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran, Tel: +98 711 228 0916, Fax: +98 711 228 0916, E-mail:
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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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Polishchuk EV, Concilli M, Iacobacci S, Chesi G, Pastore N, Piccolo P, Paladino S, Baldantoni D, van IJzendoorn SCD, Chan J, Chang CJ, Amoresano A, Pane F, Pucci P, Tarallo A, Parenti G, Brunetti-Pierri N, Settembre C, Ballabio A, Polishchuk RS. Wilson disease protein ATP7B utilizes lysosomal exocytosis to maintain copper homeostasis. Dev Cell 2014; 29:686-700. [PMID: 24909901 PMCID: PMC4070386 DOI: 10.1016/j.devcel.2014.04.033] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 03/15/2014] [Accepted: 04/29/2014] [Indexed: 12/24/2022]
Abstract
Copper is an essential yet toxic metal and its overload causes Wilson disease, a disorder due to mutations in copper transporter ATP7B. To remove excess copper into the bile, ATP7B traffics toward canalicular area of hepatocytes. However, the trafficking mechanisms of ATP7B remain elusive. Here, we show that, in response to elevated copper, ATP7B moves from the Golgi to lysosomes and imports metal into their lumen. ATP7B enables lysosomes to undergo exocytosis through the interaction with p62 subunit of dynactin that allows lysosome translocation toward the canalicular pole of hepatocytes. Activation of lysosomal exocytosis stimulates copper clearance from the hepatocytes and rescues the most frequent Wilson-disease-causing ATP7B mutant to the appropriate functional site. Our findings indicate that lysosomes serve as an important intermediate in ATP7B trafficking, whereas lysosomal exocytosis operates as an integral process in copper excretion and hence can be targeted for therapeutic approaches to combat Wilson disease.
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Affiliation(s)
- Elena V Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Mafalda Concilli
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Simona Iacobacci
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Giancarlo Chesi
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Nunzia Pastore
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy; Jan and Dan Duncan Neurological Research Institute, Houston, TX 77030, USA
| | - Pasquale Piccolo
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Simona Paladino
- Department of Molecular Medicine and Medical Biotechnology, Federico II University, Naples 80125, Italy
| | | | - Sven C D van IJzendoorn
- Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen 9713, the Netherlands
| | - Jefferson Chan
- Department of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Christopher J Chang
- Department of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Angela Amoresano
- Department of Chemical Sciences, University of Naples Federico II, Napoli 80126, Italy
| | - Francesca Pane
- Department of Chemical Sciences, University of Naples Federico II, Napoli 80126, Italy
| | - Piero Pucci
- Department of Chemical Sciences, University of Naples Federico II, Napoli 80126, Italy
| | - Antonietta Tarallo
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy
| | - Giancarlo Parenti
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy; Medical Genetics, Department of Translational and Medical Sciences, Federico II University, Naples 80125, Italy
| | - Nicola Brunetti-Pierri
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy; Medical Genetics, Department of Translational and Medical Sciences, Federico II University, Naples 80125, Italy
| | - Carmine Settembre
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy; Jan and Dan Duncan Neurological Research Institute, Houston, TX 77030, USA; Medical Genetics, Department of Translational and Medical Sciences, Federico II University, Naples 80125, Italy; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Dulbecco Telethon Institute, TIGEM, Naples 80131, Italy
| | - Andrea Ballabio
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy; Jan and Dan Duncan Neurological Research Institute, Houston, TX 77030, USA; Medical Genetics, Department of Translational and Medical Sciences, Federico II University, Naples 80125, Italy; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Roman S Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), Naples 80131, Italy.
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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: 501] [Impact Index Per Article: 50.1] [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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40
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Slim CL, van IJzendoorn SCD, Lázaro-Diéguez F, Müsch A. The special case of hepatocytes: unique tissue architecture calls for a distinct mode of cell division. BIOARCHITECTURE 2014; 4:47-52. [PMID: 24769852 DOI: 10.4161/bioa.29012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Columnar epithelia (e.g., kidney, intestine) and hepatocytes embody the two major organizational phenotypes of non-stratified epithelial cells. Columnar epithelia establish their apical and basal domains at opposing poles and organize in monolayered cysts and tubules, in which their apical surfaces form a single continuous lumen whereas hepatocytes establish their apical domains in the midst of their basolateral domains and organize a highly branched capillary luminal network, the bile canaliculi, in which a single hepatocyte can engage in lumen formation with multiple neighbors. To maintain their distinct tissue architectures, columnar epithelial cells bisect their luminal domains during symmetric cell divisions, while the cleavage furrow in dividing hepatocytes avoids bisecting the bile canalicular domains. We discuss recently discovered molecular mechanisms that underlie the different cell division phenotypes in columnar and hepatocytic model cell lines. The serine/threonine kinase Par1b determines both the epithelial lumen polarity and cell division phenotype via cell adhesion signaling that converges on the small GTPase RhoA.
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Affiliation(s)
- Christiaan L Slim
- Department of Cell Biology; University of Groningen; University Medical Center Groningen; Groningen, The Netherlands
| | - Sven C D van IJzendoorn
- Department of Cell Biology; University of Groningen; University Medical Center Groningen; Groningen, The Netherlands
| | - Francisco Lázaro-Diéguez
- Department of Developmental and Molecular Biology; Albert Einstein College of Medicine; The Bronx, NY, USA
| | - Anne Müsch
- Department of Developmental and Molecular Biology; Albert Einstein College of Medicine; The Bronx, NY, USA
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Wang T, Yanger K, Stanger BZ, Cassio D, Bi E. Cytokinesis defines a spatial landmark for hepatocyte polarization and apical lumen formation. J Cell Sci 2014; 127:2483-92. [PMID: 24706948 DOI: 10.1242/jcs.139923] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
By definition, all epithelial cells have apical-basal polarity, but it is unclear how epithelial polarity is acquired and how polarized cells engage in tube formation. Here, we show that hepatocyte polarization is linked to cytokinesis using the rat hepatocyte cell line Can 10. Before abscission, polarity markers are delivered to the site of cell division in a strict spatiotemporal order. Immediately after abscission, daughter cells remain attached through a unique disc-shaped structure, which becomes the site for targeted exocytosis, resulting in the formation of a primitive bile canaliculus. Subsequently, oriented cell division and asymmetric cytokinesis occur at the bile canaliculus midpoint, resulting in its equal partitioning into daughter cells. Finally, successive cycles of oriented cell division and asymmetric cytokinesis lead to the formation of a tubular bile canaliculus, which is shared by two rows of hepatocytes. These findings define a novel mechanism for cytokinesis-linked polarization and tube formation, which appears to be broadly conserved in diverse cell types.
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Affiliation(s)
- Ting Wang
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kilangsungla Yanger
- Gastroenterology Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ben Z Stanger
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA Gastroenterology Division, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Doris Cassio
- INSERM, UMR-S 757, Université Paris-Sud, Orsay, F-91405, France
| | - Erfei Bi
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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42
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Mark/Par-1 Marking the Polarity of Migrating Neurons. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 800:97-111. [DOI: 10.1007/978-94-007-7687-6_6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Par1b induces asymmetric inheritance of plasma membrane domains via LGN-dependent mitotic spindle orientation in proliferating hepatocytes. PLoS Biol 2013; 11:e1001739. [PMID: 24358023 PMCID: PMC3866089 DOI: 10.1371/journal.pbio.1001739] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 11/05/2013] [Indexed: 01/06/2023] Open
Abstract
Proliferating hepatocytes in the liver show an atypical, asymmetric mode of cell division, which is coordinated by Par1b and LGN and may explain the unique tissue architecture of the liver. The development and maintenance of polarized epithelial tissue requires a tightly controlled orientation of mitotic cell division relative to the apical polarity axis. Hepatocytes display a unique polarized architecture. We demonstrate that mitotic hepatocytes asymmetrically segregate their apical plasma membrane domain to the nascent daughter cells. The non-polarized nascent daughter cell can form a de novo apical domain with its new neighbor. This asymmetric segregation of apical domains is facilitated by a geometrically distinct “apicolateral” subdomain of the lateral surface present in hepatocytes. The polarity protein partitioning-defective 1/microtubule-affinity regulating kinase 2 (Par1b/MARK2) translates this positional landmark to cortical polarity by promoting the apicolateral accumulation of Leu-Gly-Asn repeat-enriched protein (LGN) and the capture of nuclear mitotic apparatus protein (NuMA)–positive astral microtubules to orientate the mitotic spindle. Proliferating hepatocytes thus display an asymmetric inheritance of their apical domains via a mechanism that involves Par1b and LGN, which we postulate serves the unique tissue architecture of the developing liver parenchyma. The development and maintenance of the polarized epithelial architecture and function of organs that form tubular “lumen” structures is important for normal physiology and, when deregulated, gives rise to disease. Recent studies have highlighted the importance of a strict coordination of the orientation of mitotic divisions relative to an internal axis of asymmetry in proliferating epithelial cells during this process. Hepatocytes are the predominant epithelial cells of the liver. Hepatocytes display a unique lumen-forming architecture and cellular asymmetry, but the molecular basis for this special polarized architecture is not well understood. Our study now reveals an unexpected mode of plasma membrane domain inheritance that is coupled to a cellular axis of asymmetry in proliferating mammalian hepatocytes. We show that mitotic hepatocytes asymmetrically segregate their apical plasma membrane (the membrane facing the lumen structure) along with the lumen to their daughter cells. We demonstrate that the coordinated action of two proteins, Par1b and LGN, constitutes a fundamental part of the underlying molecular mechanism. This coupling of cell division and polarity in hepatocytes is distinct from that established in other epithelial cell types. These findings are important for understanding the unique polarized tissue architecture in the developing liver.
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44
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Lázaro-Diéguez F, Cohen D, Fernandez D, Hodgson L, van Ijzendoorn SCD, Müsch A. Par1b links lumen polarity with LGN-NuMA positioning for distinct epithelial cell division phenotypes. ACTA ACUST UNITED AC 2013; 203:251-64. [PMID: 24165937 PMCID: PMC3812971 DOI: 10.1083/jcb.201303013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Columnar epithelia establish their luminal domains and their mitotic spindles parallel to the basal surface and undergo symmetric cell divisions in which the cleavage furrow bisects the apical domain. Hepatocyte lumina interrupt the lateral domain of neighboring cells perpendicular to two basal domains and their cleavage furrow rarely bifurcates the luminal domains. We determine that the serine/threonine kinase Par1b defines lumen position in concert with the position of the astral microtubule anchoring complex LGN-NuMA to yield the distinct epithelial division phenotypes. Par1b signaling via the extracellular matrix (ECM) in polarizing cells determined RhoA/Rho-kinase activity at cell-cell contact sites. Columnar MDCK and Par1b-depleted hepatocytic HepG2 cells featured high RhoA activity that correlated with robust LGN-NuMA recruitment to the metaphase cortex, spindle alignment with the substratum, and columnar organization. Reduced RhoA activity at the metaphase cortex in HepG2 cells and Par1b-overexpressing MDCK cells correlated with a single or no LGN-NuMA crescent, tilted spindles, and the development of lateral lumen polarity.
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Affiliation(s)
- Francisco Lázaro-Diéguez
- Department of Developmental and Molecular Biology and 2 Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY 10461
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45
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Lewandowski KT, Piwnica-Worms H. Phosphorylation of the E3 ubiquitin ligase RNF41 by the kinase Par-1b is required for epithelial cell polarity. J Cell Sci 2013; 127:315-27. [PMID: 24259665 DOI: 10.1242/jcs.129148] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The establishment and maintenance of cell polarity is an essential property governing organismal homeostasis, and loss of polarity is a common feature of cancer cells. The ability of epithelial cells to establish apical-basal polarity depends on intracellular signals generated from polarity proteins, such as the Par-1 family of proteins, as well as extracellular signals generated through cell contacts with the extracellular matrix (ECM). The Par-1 family has a well-established role in regulating cell-cell contacts in the form of tight junctions by phosphorylating Par-3. In addition, Par-1 has been shown to impact on cell-ECM interactions by regulating laminin receptor localization and laminin deposition on the basal surface of epithelial cells. Laminins are major structural and signaling components of basement membrane (BM), a sheet of specialized ECM underlying epithelia. In this study, we identify RNF41, an E3 ubiquitin ligase, as a novel Par-1b (also known as MARK2) effector in the cell-ECM pathway. Par-1b binds to and phosphorylates RNF41 on serine 254. Phosphorylation of RNF41 by Par-1b is required for epithelial cells to localize laminin-111 receptors to their basolateral surfaces and to properly anchor to laminin-111. In addition, phosphorylation of RNF41 is required for epithelial cells to establish apical-basal polarity. Our data suggests that phosphorylation of RNF41 by Par-1b regulates basolateral membrane targeting of laminin-111 receptors, thereby facilitating cell anchorage to laminin-111 and ultimately forming the cell-ECM contacts required for epithelial cells to establish apical-basal cell polarity.
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Affiliation(s)
- Katherine T Lewandowski
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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46
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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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Stein M, Ruggiero P, Rappuoli R, Bagnoli F. Helicobacter pylori CagA: From Pathogenic Mechanisms to Its Use as an Anti-Cancer Vaccine. Front Immunol 2013; 4:328. [PMID: 24133496 PMCID: PMC3796731 DOI: 10.3389/fimmu.2013.00328] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 09/25/2013] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori colonizes the gastric mucosa of more than 50% of the human population, causing chronic inflammation, which however is largely asymptomatic. Nevertheless, H. pylori-infected subjects can develop chronic gastritis, peptic ulcer, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Chronic exposure to the pathogen and its ability to induce epithelial to mesenchymal transition (EMT) through the injection of cytotoxin-associated gene A into gastric epithelial cells may be key triggers of carcinogenesis. By deregulating cell-cell and cell-matrix interactions as well as DNA methylation, histone modifications, expression of micro RNAs, and resistance to apoptosis, EMT can actively contribute to early stages of the cancer formation. Host response to the infection significantly contributes to disease development and the concomitance of particular genotypes of both pathogen and host may turn into the most severe outcomes. T regulatory cells (Treg) have been recently demonstrated to play an important role in H. pylori-related disease development and at the same time the Treg-induced tolerance has been proposed as a possible mechanism that leads to less severe disease. Efficacy of antibiotic therapies of H. pylori infection has significantly dropped. Unfortunately, no vaccine against H. pylori is currently licensed, and protective immunity mechanisms against H. pylori are only partially understood. In spite of promising results obtained in animal models of infection with a number of vaccine candidates, few clinical trials have been conducted so far and with no satisfactory outcomes. However, prophylactic vaccination may be the only means to efficiently prevent H. pylori-associated cancers.
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Affiliation(s)
- Markus Stein
- Albany College of Pharmacy and Health Sciences, Albany, NY, USA
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48
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Zhang H, Kim A, Abraham N, Khan LA, Göbel V. Vesicular sorting controls the polarity of expanding membranes in the C. elegans intestine. WORM 2013; 2:e23702. [PMID: 24058862 PMCID: PMC3670463 DOI: 10.4161/worm.23702] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Accepted: 01/16/2013] [Indexed: 11/19/2022]
Abstract
Biological tubes consist of polarized epithelial cells with apical membranes building the central lumen and basolateral membranes contacting adjacent cells or the extracellular matrix. Cellular polarity requires distinct inputs from outside the cell, e.g., the matrix, inside the cell, e.g., vesicular trafficking and the plasma membrane and its junctions.1 Many highly conserved polarity cues have been identified, but their integration during the complex process of polarized tissue and organ morphogenesis is not well understood. It is assumed that plasma-membrane-associated polarity determinants, such as the partitioning-defective (PAR) complex, define plasma membrane domain identities, whereas vesicular trafficking delivers membrane components to these domains, but lacks the ability to define them. In vitro studies on lumenal membrane biogenesis in mammalian cell lines now indicate that trafficking could contribute to defining membrane domains by targeting the polarity determinants, e.g., the PARs, themselves.2 This possibility suggests a mechanism for PARs’ asymmetric distribution on membranes and places vesicle-associated polarity cues upstream of membrane-associated polarity determinants. In such an upstream position, trafficking might even direct multiple membrane components, not only polarity determinants, an original concept of polarized plasma membrane biogenesis3,4that was largely abandoned due to the failure to identify a molecularly defined intrinsic vesicular sorting mechanism. Our two recent studies on C. elegans intestinal tubulogenesis reveal that glycosphingolipids (GSLs) and the well-recognized vesicle components clathrin and its AP-1 adaptor are required for targeting multiple apical molecules, including polarity regulators, to the expanding apical/lumenal membrane.5,6 These findings support GSLs’ long-proposed role in in vivo polarized epithelial membrane biogenesis and development and identify a novel function in apical polarity for classical post-Golgi vesicle components. They are also compatible with a vesicle-intrinsic sorting mechanism during membrane biogenesis and suggest a model for how vesicles could acquire apical directionality during the assembly of the functionally critical polarized lumenal surfaces of epithelial tubes.
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Affiliation(s)
- Hongjie Zhang
- Department of Pediatrics; Massachusetts General Hospital; Harvard Medical School; Boston, MA USA
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49
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Zhong DS, Sun LL, Dong LX. Molecular mechanisms of LKB1 induced cell cycle arrest. Thorac Cancer 2013; 4:229-233. [PMID: 28920233 DOI: 10.1111/1759-7714.12003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 10/02/2012] [Indexed: 01/13/2023] Open
Abstract
LKB1 is a serine/threonine protein kinase mutated in patients with Peutz-Jeghers syndrome. Biallelic inactivation of LKB1 is present in up to 30% of cases of non-small cell lung cancer (NSCLC). As a tumor suppressor, LKB1 functions in arresting the cell cycle and inhibiting cell growth. LKB1 leads to induction of p21/WAF1 expression in a p53-dependent mechanism, which is mediated by cytoplasmic LKB1 initiating negative regulation of cell growth or nuclear LKB1 directly involved in transcriptional regulation of p21/WAF1. Alternatively, p53 and p21/WAF1-independent mechanism of regulating cell cycle by LKB1 is also reported.
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Affiliation(s)
- Dian-Sheng Zhong
- Department of Respiratory Medicine, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China
| | - Lin-Lin Sun
- Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin, China
| | - Li-Xia Dong
- Department of Respiratory Medicine, Tianjin Medical University General Hospital, Tianjin, China
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50
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Grosse B, Degrouard J, Jaillard D, Cassio D. Build them up and break them down: Tight junctions of cell lines expressing typical hepatocyte polarity with a varied repertoire of claudins. Tissue Barriers 2013; 1:e25210. [PMID: 24665408 PMCID: PMC3783225 DOI: 10.4161/tisb.25210] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 05/28/2013] [Accepted: 05/29/2013] [Indexed: 12/14/2022] Open
Abstract
Tight junctions (TJs) of cells expressing simple epithelial polarity have been extensively studied, but less is known about TJs of cells expressing complex polarity. In this paper we analyzed, TJs of four different lines, that form bile canaliculi (BC) and express typical hepatocyte polarity; WIF-B9, 11–3, Can 3–1, Can 10. Striking differences were observed in claudin expression. None of the cell lines produced claudin-1. WIF-B9 and 11–3 expressed only claudin-2 while Can 3–1 and Can 10 expressed claudin-2,-3,-4,-5. TJs of these two classes of lines differed in their ultra-stucture, paracellular permeability, and robustness. Lines expressing a large claudin repertoire, especially Can 10, had complex and efficient TJs, that were maintained when cells were depleted in calcium. Inversely, TJs of WIF-B9 and 11–3 were leaky, permissive and dismantled by calcium depletion. Interestingly, we found that during the polarization process, TJ proteins expressed by all lines were sequentially settled in a specific order: first occludin, ZO-1 and cingulin, then JAM-A and ZO-2, finally claudin-2. Claudins expressed only in Can lines were also sequentially settled: claudin-3 was the first settled. Inhibition of claudin-3 expression delayed BC formation in Can10 and induced the expression of simple epithelial polarity. These results highlight the role of claudins in the settlement and the efficiency of TJs in lines expressing typical hepatocyte polarity. Can 10 seems to be the most promising of these lines because of its claudin repertoire near that of hepatocytes and its capacity to form extended tubular BC sealed by efficient TJs.
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Affiliation(s)
- Brigitte Grosse
- Inserm, UMR-S 757; Orsay, France ; Université Paris-Sud; Orsay, France
| | | | | | - Doris Cassio
- Inserm, UMR-S 757; Orsay, France ; Université Paris-Sud; Orsay, France
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