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Hsiao HY, Yen TH, Wu FY, Cheng CM, Liu JW, Fan YT, Huang JJ, Nien CY. Delivery and Transcriptome Assessment of an In Vitro Three-Dimensional Proximal Tubule Model Established by Human Kidney 2 Cells in Clinical Gelatin Sponges. Int J Mol Sci 2023; 24:15547. [PMID: 37958530 PMCID: PMC10650118 DOI: 10.3390/ijms242115547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 10/10/2023] [Accepted: 10/14/2023] [Indexed: 11/15/2023] Open
Abstract
The high prevalence of kidney diseases and the low identification rate of drug nephrotoxicity in preclinical studies reinforce the need for representative yet feasible renal models. Although in vitro cell-based models utilizing renal proximal tubules are widely used for kidney research, many proximal tubule cell (PTC) lines have been indicated to be less sensitive to nephrotoxins, mainly due to altered expression of transporters under a two-dimensional culture (2D) environment. Here, we selected HK-2 cells to establish a simplified three-dimensional (3D) model using gelatin sponges as scaffolds. In addition to cell viability and morphology, we conducted a comprehensive transcriptome comparison and correlation analysis of 2D and 3D cultured HK-2 cells to native human PTCs. Our 3D model displayed stable and long-term growth with a tubule-like morphology and demonstrated a more comparable gene expression profile to native human PTCs compared to the 2D model. Many missing or low expressions of major genes involved in PTC transport and metabolic processes were restored, which is crucial for successful nephrotoxicity prediction. Consequently, we established a cost-effective yet more representative model for in vivo PTC studies and presented a comprehensive transcriptome analysis for the systematic characterization of PTC lines.
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Affiliation(s)
- Hui-Yi Hsiao
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan;
- Center for Tissue Engineering, Linkuo Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan;
| | - Tzung-Hai Yen
- Department of Nephrology, Clinical Poison Center, Linkuo Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan;
- Department of Nephrology, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan
| | - Fang-Yu Wu
- Department of Life Science, National Central University, Taoyuan 32001, Taiwan; (F.-Y.W.); (Y.-T.F.)
| | - Chao-Min Cheng
- Institute of Biomedical Engineering, National Tsing Hua University, Hsinchu 300193, Taiwan;
| | - Jia-Wei Liu
- Center for Tissue Engineering, Linkuo Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan;
| | - Yu-Ting Fan
- Department of Life Science, National Central University, Taoyuan 32001, Taiwan; (F.-Y.W.); (Y.-T.F.)
| | - Jung-Ju Huang
- Division of Reconstructive Microsurgery, Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan;
| | - Chung-Yi Nien
- Department of Life Science, National Central University, Taoyuan 32001, Taiwan; (F.-Y.W.); (Y.-T.F.)
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2
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Lin N, Zhou X, Geng X, Drewell C, Hübner J, Li Z, Zhang Y, Xue M, Marx U, Li B. Repeated dose multi-drug testing using a microfluidic chip-based coculture of human liver and kidney proximal tubules equivalents. Sci Rep 2020; 10:8879. [PMID: 32483208 PMCID: PMC7264205 DOI: 10.1038/s41598-020-65817-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 04/15/2020] [Indexed: 11/28/2022] Open
Abstract
A microfluidic multi-organ chip emulates the tissue culture microenvironment, enables interconnection of organ equivalents and overcomes interspecies differences, making this technology a promising and powerful tool for preclinical drug screening. In this study, we established a microfluidic chip-based model that enabled non-contact cocultivation of liver spheroids and renal proximal tubule barriers in a connecting media circuit over 16 days. Meanwhile, a 14-day repeated-dose systemic administration of cyclosporine A (CsA) alone or in combination with rifampicin was performed. Toxicity profiles of the two different doses of CsA on different target organs could be discriminated and that concomitant treatment with rifampicin from day6 onwards decreased the CsA concentration and attenuated the toxicity compared with that after treatment with CsA for 14 consecutive days. The latter is manifested with the changes in cytotoxicity, cell viability and apoptosis, gene expression of metabolic enzymes and transporters, and noninvasive toxicity biomarkers. The on chip coculture of the liver and the proximal tubulus equivalents showed its potential as an effective and translational tool for repeated dose multi-drug toxicity screening in the preclinical stage of drug development.
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Affiliation(s)
- Ni Lin
- Key Laboratory of Beijing for Safety Evaluation of Drugs, National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, A8 Hongda Middle Street, Beijing Economic-Technological Development Area, Beijing, 100176, P. R. China.,Department of Pharmacology, Beijing Laboratory for Biomedical Detection Technology and Instrument, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, China.,Beijing Institute for Drug Control, 25 Science Park Road, Changping District, Beijing, 102206, China
| | - Xiaobing Zhou
- Key Laboratory of Beijing for Safety Evaluation of Drugs, National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, A8 Hongda Middle Street, Beijing Economic-Technological Development Area, Beijing, 100176, P. R. China
| | - Xingchao Geng
- Key Laboratory of Beijing for Safety Evaluation of Drugs, National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, A8 Hongda Middle Street, Beijing Economic-Technological Development Area, Beijing, 100176, P. R. China
| | - Christopher Drewell
- Technische Universitaet Berlin, Institute of Biotechnology, Department Medical Biotechnology, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Juliane Hübner
- Technische Universitaet Berlin, Institute of Biotechnology, Department Medical Biotechnology, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
| | - Zuogang Li
- Key Laboratory of Beijing for Safety Evaluation of Drugs, National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, A8 Hongda Middle Street, Beijing Economic-Technological Development Area, Beijing, 100176, P. R. China
| | - Yingli Zhang
- Key Laboratory of Beijing for Safety Evaluation of Drugs, National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, A8 Hongda Middle Street, Beijing Economic-Technological Development Area, Beijing, 100176, P. R. China
| | - Ming Xue
- Department of Pharmacology, Beijing Laboratory for Biomedical Detection Technology and Instrument, School of Basic Medical Sciences, Capital Medical University, Beijing, 100069, China.
| | - Uwe Marx
- TissUse GmbH, Oudenarder Strasse 16, 13347, Berlin, Germany.
| | - Bo Li
- National Institutes for Food and Drug Control, 31 Hua Tuo road, Daxing district, Beijing, 102629, China.
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3
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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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4
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Cui J, Jin G, Yu B, Wang Z, Lin R, Huang JD. Stable knockdown of Kif5b in MDCK cells leads to epithelial-mesenchymal transition. Biochem Biophys Res Commun 2015; 463:123-9. [PMID: 26002460 DOI: 10.1016/j.bbrc.2015.05.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 05/09/2015] [Indexed: 12/20/2022]
Abstract
Polarization of epithelial cells requires vectorial sorting and transport of polarity proteins to apical or basolateral domains. Kif5b is the mouse homologue of the human ubiquitous Kinesin Heavy Chain (uKHC). To investigate the function of Kif5b in epithelial cells, we examined the phenotypes of Kif5b-deficient MDCK cells. Stable knockdown of Kif5b in MDCK cells resulted in reduced cell proliferation rate, profound changes in cell morphology, loss of epithelial cell marker, and gain of mesenchymal marker, as well as increased cell migration, invasion, and tumorigenesis abilities. E-cadherin and NMMIIA could interact with Kif5b in polarized MDCK cells, and their expression levels were decreased in Kif5b-deficient MDCK cells. Overexpression of E-cadherin and NMMIIA in Kif5b depleted MDCK cells could decrease mesenchymal marker expression and cell migration ability. These results indicate that stable knockdown of Kif5b in MDCK cells can lead to epithelial-mesenchymal transition, which is mediated by defective E-cadherin and NMMIIA expression.
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Affiliation(s)
- Ju Cui
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, Beijing, China; Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
| | - Guoxiang Jin
- Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Bin Yu
- Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Zai Wang
- Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China; Institute of Clinical Medical Sciences, China-Japan Friendship Hospital, Beijing, China
| | - Raozhou Lin
- Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Jian-Dong Huang
- Department of Biochemistry, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China; The Centre for Synthetic Biology Engineering Research, Shenzhen Institutes of Advanced Technology, Shenzhen, China.
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5
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Glotfelty LG, Zahs A, Iancu C, Shen L, Hecht GA. Microtubules are required for efficient epithelial tight junction homeostasis and restoration. Am J Physiol Cell Physiol 2014; 307:C245-54. [PMID: 24920678 DOI: 10.1152/ajpcell.00336.2013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Epithelial tight junctions are critical for creating a barrier yet allowing paracellular transport. Although it is well established that the actin cytoskeleton is critical for preserving the dynamic organization of the tight junction and maintaining normal tight junction protein recycling, contributions of microtubules to tight junction organization and function remain undefined. The aim of this study is to determine the role of microtubules in tight junction homeostasis and restoration. Our data demonstrate that occludin traffics on microtubules and that microtubule disruption perturbs tight junction structure and function. Microtubules are also shown to be required for restoring barrier function following Ca(2+) chelation and repletion. These processes are mediated by proteins participating in microtubule minus-end-directed trafficking but not plus-end-directed trafficking. These studies show that microtubules participate in the preservation of epithelial tight junction structure and function and play a vital role in tight junction restoration, thus expanding our understanding of the regulation of tight junction physiology.
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Affiliation(s)
- Lila G Glotfelty
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, Illinois
| | - Anita Zahs
- Departments of Medicine and Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois
| | - Catalin Iancu
- Departments of Medicine and Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois
| | - Le Shen
- University of Chicago, Chicago, Illinois
| | - Gail A Hecht
- Departments of Medicine and Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois; Edward Hines Jr. VA Hospital, Hines, Illinois
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6
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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: 504] [Impact Index Per Article: 50.4] [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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7
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Walch L. Emerging role of the scaffolding protein Dlg1 in vesicle trafficking. Traffic 2014; 14:964-73. [PMID: 23829493 DOI: 10.1111/tra.12089] [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: 04/05/2013] [Revised: 07/02/2013] [Accepted: 07/06/2013] [Indexed: 01/23/2023]
Abstract
Discs large 1 (Dlg1) is a modular scaffolding protein implicated in the control of cell polarity through assembly of specific multiprotein complexes, including receptors, ion channels and signaling proteins, at specialized zones of the plasma membrane. Recent data have shown that in addition to these well-known interaction partners, Dlg1 may also recruit components of the vesicle trafficking machinery either to the plasma membrane or to transport vesicles. Here, we discuss Dlg1 function in vesicle formation, targeting, tethering and fusion, in both the exocytotic and endocytotic pathways. These pathways contribute to cell functions as major and diverse as glutamatergic activity in the neurons, membrane homeostasis in Schwann cell myelination, insulin stimulation of glucose transport in adipocytes, or endothelial secretion of the hemostatic protein, von Willebrand factor (VWF).
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Affiliation(s)
- Laurence Walch
- INSERM U698, Université Paris 7, Hemostasis, Bio-engineering and Cardiovascular Remodeling, CHU X. Bichat, Paris, France.
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8
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Mazzaferri J, Costantino S, Lefrancois S. Analysis of AQP4 trafficking vesicle dynamics using a high-content approach. Biophys J 2014; 105:328-37. [PMID: 23870254 DOI: 10.1016/j.bpj.2013.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/05/2013] [Accepted: 06/07/2013] [Indexed: 01/11/2023] Open
Abstract
Aquaporin-4 (AQP4) is found on the basolateral plasma membrane of a variety of epithelial cells, and it is widely accepted that microtubules play an important role in protein trafficking to the plasma membrane. In the particular case of polarized trafficking, however, most evidence on the involvement of microtubules has been obtained via biochemistry experiments and single-shot microscopy. These approaches have provided essential information, even though they neglect the dynamical details of microtubule transport. In this work, we present a high-content framework in which time-lapse imaging, and single-particle-tracking algorithms were used to study a large number (∼10(4)) of GFP-AQP4-carrying vesicles on a large number of cells (∼170). By analyzing several descriptors in this large sample of trajectories, we were able to obtain highly statistically significant results. Our results support the hypothesis that AQP4 is transported along microtubules, but to our surprise, this transport is not directed straight to the basolateral plasma membrane. On the contrary, these vesicles move stochastically along microtubules, changing direction repeatedly. We propose that the role of microtubules in the basolateral trafficking of AQP4 is to increase the efficiency, rather than determine the specificity of the target.
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Affiliation(s)
- Javier Mazzaferri
- Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, Canada
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9
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Mackeh R, Perdiz D, Lorin S, Codogno P, Poüs C. Autophagy and microtubules - new story, old players. J Cell Sci 2013; 126:1071-80. [PMID: 23620510 DOI: 10.1242/jcs.115626] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Both at a basal level and after induction (especially in response to nutrient starvation), the function of autophagy is to allow cells to degrade and recycle damaged organelles, proteins and other biological constituents. Here, we focus on the role microtubules have in autophagosome formation, autophagosome transport across the cytoplasm and in the formation of autolysosomes. Recent insights into the exact relationship between autophagy and microtubules now point to the importance of microtubule dynamics, tubulin post-translational modifications and microtubule motors in the autophagy process. Such factors regulate signaling pathways that converge to stimulate autophagosome formation. They also orchestrate the movements of pre-autophagosomal structures and autophagosomes or more globally organize and localize immature and mature autophagosomes and lysosomes. Most of the factors that now appear to link microtubules to autophagosome formation or to autophagosome dynamics and fate were identified initially without the notion that sequestration, recruitment and/or interaction with microtubules contribute to their function. Spatial and temporal coordination of many stages in the life of autophagosomes thus underlines the integrative role of microtubules and progressively reveals hidden parts of the autophagy machinery.
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Affiliation(s)
- Rafah Mackeh
- UPRES EA4530, Université Paris-Sud, Faculté de Pharmacie, 92296 Châtenay-Malabry, France
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10
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The N-terminal basolateral targeting signal unlikely acts alone in the differential trafficking of membrane transporters in MDCK cells. Biochemistry 2013; 52:5103-5116. [PMID: 23837633 DOI: 10.1021/bi4005914] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have shown previously, using confocal imaging and transport assays, that the N-terminus of sodium-dependent vitamin C transporter 2 (SVCT2) can redirect apical SVCT1 to the basolateral membrane. Here, the SVCT model was used to further characterize the basolateral targeting peptide signal. Both the length (31 amino acids) and sequence accuracy of the N-terminus of SVCT2 were found to be important in basolateral targeting activity, suggesting a structural requirement. However, the N-terminal basolateral targeting sequence did not appear to act alone, based on analyses of heterologous chimeras. Although diverse N-terminal basolateral targeting signals from multipass membrane proteins can all redirect apical protein from the same gene family to the basolateral membrane, none of the N-terminal basolateral targeting signals can redirect the transmembrane and C-terminal regions from a different gene family. Instead, the presence of these heterologous N-terminal basolateral targeting signals affected the trafficking of otherwise apical protein, causing their accumulation in a stable tubulin-like non-actin structure. Nontargeting N-terminal sequences had no effect. Similar protein retention was observed previously and in this study when the C-terminus of apical or basolateral protein was mutated. These results suggest that the N- and C-termini interact, directly or indirectly, within each gene family for basolateral targeting. Circular dichroism and two-dimensional nuclear magnetic resonance analyses both found a lack of regular secondary structure in the conserved N-terminus of SVCT2, consistent with the presence of partner(s) in the targeting unit. Our finding, a departure from the prevailing single-peptide motif model, is consistent with the evolution of basolateral transporters from the corresponding apical genes. The interaction among the N-terminus, its partner(s), and the cellular basolateral targeting machinery needs to be further elucidated.
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11
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Campbell PD, Marlow FL. Temporal and tissue specific gene expression patterns of the zebrafish kinesin-1 heavy chain family, kif5s, during development. Gene Expr Patterns 2013; 13:271-9. [PMID: 23684767 DOI: 10.1016/j.gep.2013.05.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/01/2013] [Accepted: 05/04/2013] [Indexed: 12/25/2022]
Abstract
Homo- and heterodimers of Kif5 proteins form the motor domain of Kinesin-1, a major plus-end directed microtubule motor. Kif5s have been implicated in the intracellular transport of organelles, vesicles, proteins, and RNAs in many cell types. There are three mammalian KIF5s. KIF5A and KIF5C proteins are strictly neural in mouse whereas, KIF5B is ubiquitously expressed. Mouse knockouts indicate crucial roles for KIF5 in development and human mutations in KIF5A lead to the neurodegenerative disease Hereditary Spastic Paraplegia. However, the developmental functions and the extent to which individual kif5 functions overlap have not been elucidated. Zebrafish possess five kif5 genes: kif5Aa, kif5Ab, kif5Ba, kif5Bb, and kif5C. Here we report their tissue specific expression patterns in embryonic and larval stages. Specifically, we find that kif5As are strictly zygotic and exhibit neural-specific expression. In contrast, kif5Bs exhibit strong maternal contribution and are ubiquitously expressed. Lastly, kif5C exhibits weak maternal expression followed by enrichment in neural populations. In addition, kif5s show distinct expression domains in the larval retina.
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Affiliation(s)
- Philip D Campbell
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Yeshiva University, Bronx, NY 10461, USA
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12
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Kano F, Nakatsu D, Noguchi Y, Yamamoto A, Murata M. A resealed-cell system for analyzing pathogenic intracellular events: perturbation of endocytic pathways under diabetic conditions. PLoS One 2012; 7:e44127. [PMID: 22952896 PMCID: PMC3430665 DOI: 10.1371/journal.pone.0044127] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 07/30/2012] [Indexed: 12/25/2022] Open
Abstract
Cell-based assay systems that can serve as cellular models of aberrant function in pathogenic organs would be novel and useful tools for screening drugs and clarifying the molecular mechanisms of various diseases. We constructed model cells that replicated the conditions in diabetic hepatocytes by using the cell resealing technique, which enables the exchange of cytosol. The plasma membrane of HeLa cells was permeabilized with the streptococcal toxin streptolysin O, and cytosol that had been prepared from wild-type or db/db diabetic mice was introduced into the resulting semi-intact cells. By resealing the plasma membrane by exposure to Ca2+, we created WT or Db model cells, in which the cytosolic conditions replicated those of healthy or diabetic liver. Interestingly, phosphorylation of p38 MAPK was promoted, whereas the level of endosomal phosphatidylinositol-3-phosphate was decreased, in Db cells. We investigated several endocytic pathways in WT and Db cells, and found that retrograde endosome-to-Golgi transport was delayed in a p38 MAPK-dependent manner in Db cells. Furthermore, the degradation pathway of the EGF receptor from endosomes to lysosomes was enhanced in Db cells, and this did not depend on the activation of p38 MAPK. The disease model cell system should become a powerful tool for the detection of aberrant processes in cells under pathogenic conditions and for therapeutic applications.
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Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
- PRESTO, Japan Science and Technology Agency, Saitama, Japan
| | - Daiki Nakatsu
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Yoshiyuki Noguchi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Akitsugu Yamamoto
- Department of Cell Biology, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan
| | - Masayuki Murata
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo, Japan
- * E-mail:
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Abstract
The polarized distribution of proteins and lipids at the surface membrane of epithelial cells results in the formation of an apical and a basolateral domain, which are separated by tight junctions. The generation and maintenance of epithelial polarity require elaborate mechanisms that guarantee correct sorting and vectorial delivery of cargo molecules. This dynamic process involves the interaction of sorting signals with sorting machineries and the formation of transport carriers. Here we review the recent advances in the field of polarized sorting in epithelial cells. We especially highlight the role of lipid rafts in apical sorting.
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14
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Van Campenhout CA, Eitelhuber A, Gloeckner CJ, Giallonardo P, Gegg M, Oller H, Grant SGN, Krappmann D, Ueffing M, Lickert H. Dlg3 trafficking and apical tight junction formation is regulated by nedd4 and nedd4-2 e3 ubiquitin ligases. Dev Cell 2011; 21:479-91. [PMID: 21920314 PMCID: PMC4452538 DOI: 10.1016/j.devcel.2011.08.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Revised: 05/24/2011] [Accepted: 08/01/2011] [Indexed: 01/01/2023]
Abstract
The Drosophila Discs large (Dlg) scaffolding protein acts as a tumor suppressor regulating basolateral epithelial polarity and proliferation. In mammals, four Dlg homologs have been identified; however, their functions in cell polarity remain poorly understood. Here, we demonstrate that the X-linked mental retardation gene product Dlg3 contributes to apical-basal polarity and epithelial junction formation in mouse organizer tissues, as well as to planar cell polarity in the inner ear. We purified complexes associated with Dlg3 in polarized epithelial cells, including proteins regulating directed trafficking and tight junction formation. Remarkably, of the four Dlg family members, Dlg3 exerts a distinct function by recruiting the ubiquitin ligases Nedd4 and Nedd4-2 through its PPxY motifs. We found that these interactions are required for Dlg3 monoubiquitination, apical membrane recruitment, and tight junction consolidation. Our findings reveal an unexpected evolutionary diversification of the vertebrate Dlg family in basolateral epithelium formation.
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15
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Etienne-Manneville S. Control of polarized cell morphology and motility by adherens junctions. Semin Cell Dev Biol 2011; 22:850-7. [PMID: 21839846 DOI: 10.1016/j.semcdb.2011.07.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2011] [Revised: 07/27/2011] [Accepted: 07/29/2011] [Indexed: 01/11/2023]
Abstract
Cell-cell interactions play a key role in tissue homeostasis. Intercellular adhesions share the complex task of establishing and maintaining tissue architecture while allowing tissue growth, renewal and repair. In particular, adherens junctions (AJs) have been implicated in the formation of diverse tissues and organs like epitheliums, blood vessels or the central nervous system. At the cellular level, AJs are well known for their essential role in epithelial cell differentiation and baso-apical polarity. They also contribute to the control of cell polarity to promote neuronal morphogenesis, growth cone guidance and directed migration in a variety of cell types during embryonic development. AJs based on classical cadherin- and nectin-mediated cell-cell interactions control local membrane dynamics to polarize cell morphology and motility at the single cell level and to coordinate cell shape changes and motile behaviour at the tissue level. I review here the molecular mechanisms allowing control of polarized cell morphology and motility by AJs.
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16
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Wickström SA, Fässler R. Regulation of membrane traffic by integrin signaling. Trends Cell Biol 2011; 21:266-73. [DOI: 10.1016/j.tcb.2011.02.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 02/20/2011] [Accepted: 02/23/2011] [Indexed: 01/23/2023]
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17
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Wickström SA, Lange A, Hess MW, Polleux J, Spatz JP, Krüger M, Pfaller K, Lambacher A, Bloch W, Mann M, Huber LA, Fässler R. Integrin-linked kinase controls microtubule dynamics required for plasma membrane targeting of caveolae. Dev Cell 2010; 19:574-88. [PMID: 20951348 PMCID: PMC2977078 DOI: 10.1016/j.devcel.2010.09.007] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 06/06/2010] [Accepted: 08/17/2010] [Indexed: 12/13/2022]
Abstract
Caveolae are specialized compartments of the plasma membrane that are involved in signaling, endocytosis, and cholesterol transport. Their formation requires the transport of caveolin-1 to the plasma membrane, but the molecular mechanisms regulating the transport are largely unknown. Here, we identify a critical role for adhesion-mediated signaling through β1 integrins and integrin-linked kinase (ILK) in caveolae formation. Mice lacking β1 integrins or ILK in keratinocytes have dramatically reduced numbers of plasma membrane caveolae in vivo, which is due to impaired transport of caveolin-1-containing vesicles along microtubules (MT) to the plasma membrane. Mechanistically, ILK promotes the recruitment of the F-actin binding protein IQGAP1 to the cell cortex, which, in turn, cooperates with its effector mDia1 to locally stabilize MTs and to allow stable insertion of caveolae into the plasma membrane. Our results assign an important role to the integrin/ILK complex for caveolar trafficking to the cell surface.
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Affiliation(s)
- Sara A Wickström
- Department of Molecular Medicine, Max-Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
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18
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Nelson WJ. Remodeling epithelial cell organization: transitions between front-rear and apical-basal polarity. Cold Spring Harb Perspect Biol 2010; 1:a000513. [PMID: 20066074 DOI: 10.1101/cshperspect.a000513] [Citation(s) in RCA: 213] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Polarized epithelial cells have a distinctive apical-basal axis of polarity for vectorial transport of ions and solutes across the epithelium. In contrast, migratory mesenchymal cells have a front-rear axis of polarity. During development, mesenchymal cells convert to epithelia by coalescing into aggregates that undergo epithelial differentiation. Signaling networks and protein complexes comprising Rho family GTPases, polarity complexes (Crumbs, PAR, and Scribble), and their downstream effectors, including the cytoskeleton and the endocytic and exocytic vesicle trafficking pathways, together regulate the distributions of plasma membrane and cytoskeletal proteins between front-rear and apical-basal polarity. The challenge is to understand how these regulators and effectors are adapted to regulate symmetry breaking processes that generate cell polarities that are specialized for different cellular activities and functions.
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Affiliation(s)
- W James Nelson
- Department of Biology, Stanford University, Stanford, California 94305, USA.
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19
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Godde NJ, Galea RC, Elsum IA, Humbert PO. Cell polarity in motion: redefining mammary tissue organization through EMT and cell polarity transitions. J Mammary Gland Biol Neoplasia 2010; 15:149-68. [PMID: 20461450 DOI: 10.1007/s10911-010-9180-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 04/27/2010] [Indexed: 02/04/2023] Open
Abstract
Epithelial to mesenchymal transition (EMT) and its reversion via mesenchymal to epithelial transition (MET), represent a stepwise cycle of epithelial plasticity that allows for normal tissue remodelling and diversification during development. In particular, epithelial-mesenchymal plasticity is central to many aspects of mammary development and has been proposed to be a key process in breast cancer progression. Such epithelial-mesenchymal plasticity requires complex cellular reprogramming to orchestrate a change in cell shape to an alternate morphology more conducive to migration. During this process, epithelial characteristics, including apical-basal polarity and specialised cell-cell junctions are lost and mesenchymal properties, such as a front-rear polarity associated with weak cell-cell contacts, increased motility, resistance to apoptosis and invasiveness are gained. The ability of epithelial cells to undergo transitions through cell polarity states is a central feature of epithelial-mesenchymal plasticity. These cell polarity states comprise a set of distinct asymmetric distributions of cellular constituents that are fashioned to allow specialized cellular functions, such as the regulated homeostasis of molecules across epithelial barriers, cell migration or cell diversification via asymmetric cell divisions. Each polarity state is engineered using a molecular toolbox that is highly conserved between organisms and cell types which can direct the initiation, establishment and continued maintenance of each asymmetry. Here we discuss how EMT pathways target cell polarity mediators, and how this EMT-dependent change in polarity states impact on the various stages of breast cancer. Emerging evidence places cell polarity at the interface of proliferation and morphology control and as such the changing dynamics within polarity networks play a critical role in normal mammary gland development and breast cancer progression.
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Affiliation(s)
- Nathan J Godde
- Cell Cycle and Cancer Genetics Laboratory, Peter MacCallum Cancer Center, East Melbourne, VIC 3002, Australia
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20
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Astanina K, Jacob R. KIF5C, a kinesin motor involved in apical trafficking of MDCK cells. Cell Mol Life Sci 2010; 67:1331-42. [PMID: 20094756 PMCID: PMC11115860 DOI: 10.1007/s00018-009-0253-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 12/22/2009] [Accepted: 12/28/2009] [Indexed: 12/28/2022]
Abstract
Polarized traffic in epithelial cells depends on well-organized pathways that direct secretory cargo to the apical or basolateral plasma membrane. In MDCK cells, apical trafficking can be further divided into a lipid raft-dependent and a raft-independent route, which separate biosynthetic cargo in a post-Golgi endosomal compartment. We have now identified KIF5C as a kinesin motor for apical trafficking of both raft-associated sucrase isomaltase and raft-independent neurotrophin receptor. KIF5C was identified by mass spectrometry in vesicle enriched fractions and on immunoisolated post-Golgi vesicles carrying apical cargo. The amount of vesicle-associated KIF5C was highest on material isolated directly after trans-Golgi network release and declined thereafter. Altogether, our data suggest that KIF5C is involved in the passage of apical cargo molecules to a post-Golgi endosomal compartment, where further segregation into distinct vesicle populations proceeds.
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Affiliation(s)
- Ksenia Astanina
- Department of Cell Biology and Cell Pathology, Philipps University of Marburg, Robert-Koch-Str. 6, 35033 Marburg, Germany
| | - Ralf Jacob
- Department of Cell Biology and Cell Pathology, Philipps University of Marburg, Robert-Koch-Str. 6, 35033 Marburg, Germany
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21
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Weisz OA, Rodriguez-Boulan E. Apical trafficking in epithelial cells: signals, clusters and motors. J Cell Sci 2010; 122:4253-66. [PMID: 19923269 DOI: 10.1242/jcs.032615] [Citation(s) in RCA: 228] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In the early days of epithelial cell biology, researchers working with kidney and/or intestinal epithelial cell lines and with hepatocytes described the biosynthetic and recycling routes followed by apical and basolateral plasma membrane (PM) proteins. They identified the trans-Golgi network and recycling endosomes as the compartments that carried out apical-basolateral sorting. They described complex apical sorting signals that promoted association with lipid rafts, and simpler basolateral sorting signals resembling clathrin-coated-pit endocytic motifs. They also noticed that different epithelial cell types routed their apical PM proteins very differently, using either a vectorial (direct) route or a transcytotic (indirect) route. Although these original observations have generally held up, recent studies have revealed interesting complexities in the routes taken by apically destined proteins and have extended our understanding of the machinery required to sustain these elaborate sorting pathways. Here, we critically review the current status of apical trafficking mechanisms and discuss a model in which clustering is required to recruit apical trafficking machineries. Uncovering the mechanisms responsible for polarized trafficking and their epithelial-specific variations will help understand how epithelial functional diversity is generated and the pathogenesis of many human diseases.
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Affiliation(s)
- Ora A Weisz
- Department of Medicine and Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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22
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Cai D, McEwen DP, Martens JR, Meyhofer E, Verhey KJ. Single molecule imaging reveals differences in microtubule track selection between Kinesin motors. PLoS Biol 2009; 7:e1000216. [PMID: 19823565 PMCID: PMC2749942 DOI: 10.1371/journal.pbio.1000216] [Citation(s) in RCA: 239] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Accepted: 09/01/2009] [Indexed: 11/23/2022] Open
Abstract
Molecular motors differentially recognize and move cargo along discrete microtubule subpopulations in cells, resulting in preferential transport and targeting of subcellular cargoes. Cells generate diverse microtubule populations by polymerization of a common α/β-tubulin building block. How microtubule associated proteins translate microtubule heterogeneity into specific cellular functions is not clear. We evaluated the ability of kinesin motors involved in vesicle transport to read microtubule heterogeneity by using single molecule imaging in live cells. We show that individual Kinesin-1 motors move preferentially on a subset of microtubules in COS cells, identified as the stable microtubules marked by post-translational modifications. In contrast, individual Kinesin-2 (KIF17) and Kinesin-3 (KIF1A) motors do not select subsets of microtubules. Surprisingly, KIF17 and KIF1A motors that overtake the plus ends of growing microtubules do not fall off but rather track with the growing tip. Selection of microtubule tracks restricts Kinesin-1 transport of VSVG vesicles to stable microtubules in COS cells whereas KIF17 transport of Kv1.5 vesicles is not restricted to specific microtubules in HL-1 myocytes. These results indicate that kinesin families can be distinguished by their ability to recognize microtubule heterogeneity. Furthermore, this property enables kinesin motors to segregate membrane trafficking events between stable and dynamic microtubule populations. Eukaryotic cells assemble a variety of cytoskeletal structures from a set of highly conserved building blocks. For example, all microtubules are generated by the polymerization of a common α/β-tubulin subunit, yet cells can contain diverse, discrete populations of microtubule structures such as axonemes, spindles, and radial arrays. This diversity must be read and translated by cellular components in order to carry out population-specific functions. We use single-molecule imaging to study how molecular motors navigate the heterogeneous microtubule populations present in interphase cells. We show that different kinesin motors select different subpopulations of microtubules for transport. This selectivity, based solely on the motor-microtubule interface, may enable kinesin motors to segregate transport events to distinct microtubule populations and thus to target cargoes to specific subcellular destinations.
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Affiliation(s)
- Dawen Cai
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Biophysics Research Division, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Dyke P. McEwen
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jeffery R. Martens
- Department of Pharmacology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Edgar Meyhofer
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan, United States of America
- Biophysics Research Division, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Kristen J. Verhey
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Biophysics Research Division, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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23
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Schnekenburger J, Weber IA, Hahn D, Buchwalow I, Krüger B, Albrecht E, Domschke W, Lerch MM. The role of kinesin, dynein and microtubules in pancreatic secretion. Cell Mol Life Sci 2009; 66:2525-37. [PMID: 19488676 PMCID: PMC11115865 DOI: 10.1007/s00018-009-0052-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 05/08/2009] [Accepted: 05/13/2009] [Indexed: 10/20/2022]
Abstract
The regulated secretion of pancreatic zymogens depends on a functional cytoskeleton and intracellular vesicle transport. To study the dynamics of tubulin and its motor proteins dynein and kinesin during secretion in pancreatic acinar cells, we infused rats with 0.1 mug/kg/h caerulein. Electron and fluorescence microscopy detected neither dynein nor kinesin at the apical secretory pole, nor on the surface of mature zymogen granules. After 30 min of secretagogue stimulation, kinesin and the Golgi marker protein 58 K were reallocated towards the apical plasma membrane and association of kinesin with tubulin was enhanced. Disruption of acinar cell microtubules had no effect on initial caerulein-induced amylase release but completely blocked secretion during a second stimulus. Our results suggest that mature zymogen granule exocytosis is independent of intact microtubules, kinesin and dynein. However, microtubule-dependent mechanisms seem to be important for the replenishment of secretory vesicles by redistribution of Golgi elements towards the apical cell pole.
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Affiliation(s)
- Jürgen Schnekenburger
- Department of Medicine B, Westfälische Wilhelms-University, Domagkstr. 3A, 48149 Münster, Germany.
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24
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Brownhill K, Wood L, Allan V. Molecular motors and the Golgi complex: staying put and moving through. Semin Cell Dev Biol 2009; 20:784-92. [PMID: 19446479 DOI: 10.1016/j.semcdb.2009.03.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 03/30/2009] [Accepted: 03/31/2009] [Indexed: 11/19/2022]
Abstract
The Golgi apparatus is a highly dynamic organelle through which nascent proteins released from the endoplasmic reticulum (ER) are trafficked. Proteins are post-translationally modified within the Golgi and subsequently packaged into carriers for transport to a variety of cellular destinations. This transit of proteins, as well as the maintenance of Golgi structure and position, is highly dependent upon the actin and microtubule cytoskeletons and their associated molecular motors. Here we review how motors contribute to the correct functioning of the Golgi in higher eukaryotes and discuss the secretory pathway as a model system for studying cooperation between motor proteins.
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Affiliation(s)
- Kim Brownhill
- University of Manchester, Faculty of Life Sciences, The Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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25
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Mushinski JF, Nguyen P, Stevens LM, Khanna C, Lee S, Chung EJ, Lee MJ, Kim YS, Linehan WM, Horisberger MA, Trepel JB. Inhibition of tumor cell motility by the interferon-inducible GTPase MxA. J Biol Chem 2009; 284:15206-14. [PMID: 19297326 DOI: 10.1074/jbc.m806324200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
To identify pathways controlling prostate cancer metastasis we performed differential display analysis of the human prostate carcinoma cell line PC-3 and its highly metastatic derivative PC-3M. This revealed that a 78-kDa interferon-inducible GTPase, MxA, was expressed in PC-3 but not in PC-3M cells. The gene encoding MxA, MX1, is located in the region of chromosome 21 deleted as a consequence of fusion of TMPRSS2 and ERG, which has been associated with aggressive, invasive prostate cancer. Stable exogenous MxA expression inhibited in vitro motility and invasiveness of PC-3M cells. In vivo exogenous MxA expression decreased the number of hepatic metastases following intrasplenic injection. Exogenous MxA also reduced motility and invasiveness of highly metastatic LOX melanoma cells. A mutation in MxA that inactivated its GTPase reversed inhibition of motility and invasion in both tumor cell lines. Co-immunoprecipitation studies demonstrated that MxA associated with tubulin, but the GTPase-inactivating mutation blocked this association. Because MxA is a highly inducible gene, an MxA-targeted drug discovery screen was initiated by placing the MxA promoter upstream of a luciferase reporter. Examination of the NCI diversity set of small molecules revealed three hits that activated the promoter. In PC-3M cells, these drugs induced MxA protein and inhibited motility. These data demonstrate that MxA inhibits tumor cell motility and invasion, and that MxA expression can be induced by small molecules, potentially offering a new approach to the prevention and treatment of metastasis.
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Affiliation(s)
- J Frederic Mushinski
- Laboratory of Cancer Biology and Genetics, Medical Oncology Branch, Pediatric Oncology Branch, and Urologic Oncology Branch, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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26
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Coordinated protein sorting, targeting and distribution in polarized cells. Nat Rev Mol Cell Biol 2008; 9:833-45. [PMID: 18946473 DOI: 10.1038/nrm2525] [Citation(s) in RCA: 396] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The polarized distribution of functions in polarized cells requires the coordinated interaction of three machineries that modify the basic mechanisms of intracellular protein trafficking and distribution. First, intrinsic protein-sorting signals and cellular decoding machineries regulate protein trafficking to plasma membrane domains; second, intracellular signalling complexes define the plasma membrane domains to which proteins are delivered; and third, proteins that are involved in cell-cell and cell-substrate adhesion orientate the three-dimensional distribution of intracellular signalling complexes and, accordingly, the direction of membrane traffic. The integration of these mechanisms into a complex and dynamic network is crucial for normal tissue function and is often defective in disease states.
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27
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Horne-Badovinac S, Bilder D. Dynein regulates epithelial polarity and the apical localization of stardust A mRNA. PLoS Genet 2008; 4:e8. [PMID: 18208331 PMCID: PMC2213700 DOI: 10.1371/journal.pgen.0040008] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Accepted: 11/27/2007] [Indexed: 11/19/2022] Open
Abstract
Intense investigation has identified an elaborate protein network controlling epithelial polarity. Although precise subcellular targeting of apical and basolateral determinants is required for epithelial architecture, little is known about how the individual determinant proteins become localized within the cell. Through a genetic screen for epithelial defects in the Drosophila follicle cells, we have found that the cytoplasmic Dynein motor is an essential regulator of apico–basal polarity. Our data suggest that Dynein acts through the cytoplasmic scaffolding protein Stardust (Sdt) to localize the transmembrane protein Crumbs, in part through the apical targeting of specific sdt mRNA isoforms. We have mapped the sdt mRNA localization signal to an alternatively spliced coding exon. Intriguingly, the presence or absence of this exon corresponds to a developmental switch in sdt mRNA localization in which apical transcripts are only found during early stages of epithelial development, while unlocalized transcripts predominate in mature epithelia. This work represents the first demonstration that Dynein is required for epithelial polarity and suggests that mRNA localization may have a functional role in the regulation of apico–basal organization. Moreover, we introduce a unique mechanism in which alternative splicing of a coding exon is used to control mRNA localization during development. Cells within epithelial sheets are highly polarized with distinct apical and basolateral membrane domains. This cellular organization is critical to both epithelial form and function, and a failure to maintain epithelial polarity is often linked to tumor progression. The protein network that establishes and maintains the two membrane domains relies on the precise subcellular localization of its molecular components, but little is known about how these proteins are targeted to their sites of action. We have shown that the localization of the apical determinant protein Stardust depends on the microtubule motor Dynein. While investigating the relationship between Dynein and Stardust, we also made two unexpected observations about stardust mRNA regulation. First, the mechanism by which Dynein localizes Stardust may depend, in part, on the apical targeting of the stardust mRNA. Second, some stardust mRNA is apically localized during early stages of epithelial development, but the selective removal of the apical localization signal leads to the sole production of uniformly localized transcripts in mature epithelial cells. Together, these results introduce roles for Dynein in apico–basal polarity regulation and raise important questions about the role of mRNA localization in the targeting of polarity determinant proteins and epithelial maturation.
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Affiliation(s)
- Sally Horne-Badovinac
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, California, United States of America
| | - David Bilder
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, California, United States of America
- * To whom correspondence should be addressed. E-mail:
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28
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Fölsch H. Regulation of membrane trafficking in polarized epithelial cells. Curr Opin Cell Biol 2008; 20:208-13. [PMID: 18282697 DOI: 10.1016/j.ceb.2008.01.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 01/04/2008] [Indexed: 12/27/2022]
Abstract
Polarized epithelial cells continuously sort transmembrane proteins to either apical or basolateral plasma membrane domains. Research in recent years has made tremendous progress in understanding the molecular mechanisms of the major pathways to either basolateral or apical domain. This understanding will help us elucidating how these pathways are interconnected in ensuring maintenance of cell polarity and integrity of epithelial monolayers.
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Affiliation(s)
- Heike Fölsch
- Department of Biochemistry, Molecular Biology & Cell Biology, Northwestern University, 2205 Tech Drive, Evanston, IL 60202, USA.
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29
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Spiliotis ET, Hunt SJ, Hu Q, Kinoshita M, Nelson WJ. Epithelial polarity requires septin coupling of vesicle transport to polyglutamylated microtubules. ACTA ACUST UNITED AC 2008; 180:295-303. [PMID: 18209106 PMCID: PMC2213583 DOI: 10.1083/jcb.200710039] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In epithelial cells, polarized growth and maintenance of apical and basolateral plasma membrane domains depend on protein sorting from the trans-Golgi network (TGN) and vesicle delivery to the plasma membrane. Septins are filamentous GTPases required for polarized membrane growth in budding yeast, but whether they function in epithelial polarity is unknown. Here, we show that in epithelial cells septin 2 (SEPT2) fibers colocalize with a subset of microtubule tracks composed of polyglutamylated (polyGlu) tubulin, and that vesicles containing apical or basolateral proteins exit the TGN along these SEPT2/polyGlu microtubule tracks. Tubulin-associated SEPT2 facilitates vesicle transport by maintaining polyGlu microtubule tracks and impeding tubulin binding of microtubule-associated protein 4 (MAP4). Significantly, this regulatory step is required for polarized, columnar-shaped epithelia biogenesis; upon SEPT2 depletion, cells become short and fibroblast-shaped due to intracellular accumulation of apical and basolateral membrane proteins, and loss of vertically oriented polyGlu microtubules. We suggest that septin coupling of the microtubule cytoskeleton to post-Golgi vesicle transport is required for the morphogenesis of polarized epithelia.
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Affiliation(s)
- Elias T Spiliotis
- Department of Biology, Stanford University, Stanford, CA 94305, USA.
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30
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Abstract
As epithelial cells become polarized, they develop new pathways to send proteins to the apical or basolateral domains of their plasma membrane. In this issue of Developmental Cell, Jaulin et al. (2007) show that as polarity develops, there is a shift in the kinesin motor protein used to transport an apical protein to the cell surface.
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Affiliation(s)
- Catherine Jacobson
- Department of Anatomy and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143, USA
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31
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Polarization-dependent selective transport to the apical membrane by KIF5B in MDCK cells. Dev Cell 2008; 13:511-22. [PMID: 17925227 DOI: 10.1016/j.devcel.2007.08.001] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Revised: 05/13/2007] [Accepted: 08/01/2007] [Indexed: 02/01/2023]
Abstract
Microtubule-based vesicular transport is well documented in epithelial cells, but the specific motors involved and their regulation during polarization are largely unknown. We demonstrate that KIF5B mediates post-Golgi transport of an apical protein in epithelial cells, but only after polarity has developed. Time-lapse imaging of EB1-GFP in polarized MDCK cells showed microtubule plus ends growing toward the apical membrane, implying that plus end-directed N-kinesins might be used to transport apical proteins. Indeed, time-lapse microscopy revealed that expression of a KIF5B dominant negative or microinjection of function-blocking KIF5 antibodies inhibited selectively post-Golgi transport of the apical marker, p75-GFP, after polarization of MDCK cells. Expression of other KIF dominant negatives did not alter p75-GFP trafficking. Immunoprecipitation experiments demonstrated an interaction between KIF5B and p75-GFP in polarized, but not in subconfluent, MDCK cells. Our results demonstrate that apical protein transport depends on selective microtubule motors and that epithelial cells switch kinesins for post-Golgi transport during acquisition of polarity.
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32
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Duffield A, Caplan MJ, Muth TR. Chapter 4 Protein Trafficking in Polarized Cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 270:145-79. [DOI: 10.1016/s1937-6448(08)01404-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Suzuki T, Matsuzaki T, Hagiwara H, Aoki T, Tajika-Takahashi Y, Takata K. Apical localization of sodium-dependent glucose transporter SGLT1 is maintained by cholesterol and microtubules. Acta Histochem Cytochem 2006; 39:155-61. [PMID: 17327902 PMCID: PMC1779948 DOI: 10.1267/ahc.06024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2006] [Accepted: 10/23/2006] [Indexed: 01/10/2023] Open
Abstract
A GFP-labeled sodium-dependent glucose transporter SGLT1 (SGLT-GFP) was transfected into MDCK cells. SGLT-GFP was localized at the apical membrane in confluent cells. When cellular cholesterol was depleted by methyl-β-cyclodextrin (MβCD) treatment, the localization of SGLT-GFP gradually switched from apical to whole plasma membrane. Time-lapse microscopy revealed that the effect of MβCD appeared within 30 min, and that the transition of SGLT-GFP to the whole plasma membrane was completed within 2 hr after the administration. Immunofluorescence microscopy revealed that the tight junction framework remained steady during this process. The effect of MβCD on SGLT-GFP localization was counterbalanced by the addition of cholesterol into the culture medium. Disruption of microtubules by colcemid also perturbed SGLT-GFP localization. SGLT-GFP localized to the whole plasma membrane by colcemid treatment, and apical localization was restored within 1 hr after removal of colcemid. Inhibition of protein synthesis by cycloheximide had no effect on the transition of SGLT-GFP induced by the MβCD or colcemid. These results indicated that the apical localization of SGLT-GFP is maintained by cellular cholesterol and microtubules, possibly with an apical recycling machinery.
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Affiliation(s)
- Takeshi Suzuki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
- Correspondence to: Takeshi Suzuki, Ph.D., Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Showa-machi 3–39–22, Maebashi, Gunma 371–8511, Japan. E-mail:
| | - Toshiyuki Matsuzaki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
| | - Haruo Hagiwara
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
| | - Takeo Aoki
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
| | - Yukiko Tajika-Takahashi
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
| | - Kuniaki Takata
- Department of Anatomy and Cell Biology, Gunma University Graduate School of Medicine, Maebashi, Gunma 371–8511, Japan
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Yeh TY, Peretti D, Chuang JZ, Rodriguez-Boulan E, Sung CH. Regulatory dissociation of Tctex-1 light chain from dynein complex is essential for the apical delivery of rhodopsin. Traffic 2006; 7:1495-502. [PMID: 16956385 PMCID: PMC3873093 DOI: 10.1111/j.1600-0854.2006.00482.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Post-Golgi to apical surface delivery in polarized epithelial cells requires the cytoplasmic dynein motor complex. However, the nature of dynein-cargo interactions and their underlying regulation are largely unknown. Previous studies have shown that the apical surface targeting of rhodopsin requires the dynein light chain, Tctex-1, which binds directly to both dynein intermediate chain (IC) and rhodopsin. In this report, we show that the S82E mutant of Tctex-1, which mimics Tctex-1 phosphorylated at serine 82, has a reduced affinity for dynein IC but not for rhodopsin. Velocity sedimentation experiments further suggest that S82E is not incorporated into the dynein complex. The dominant-negative effect of S82E causes rhodopsin mislocalization in polarized Madin-Darby canine kidney (MDCK) cells. The S82A mutant, which mimics dephosphorylated Tctex-1, can be incorporated into dynein complex but is impaired in its release. Expression of S82A also causes disruption of the apical localization of rhodopsin in MDCK cells. Taken together, these results suggest that the dynein complex disassembles to release cargo due to the specific phosphorylation of Tctex-1 at the S82 residue and that this process is critical for the apical delivery of membrane cargoes.
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Affiliation(s)
- Ting-Yu Yeh
- Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
| | - Diego Peretti
- Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
| | - Jen-Zen Chuang
- Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
| | - Enrique Rodriguez-Boulan
- Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
| | - Ching-Hwa Sung
- Department of Ophthalmology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
- Department of Cell and Developmental Biology, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021, USA
- Corresponding author: Ching-Hwa Sung,
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35
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Kano F, Takenaka K, Murata M. Reconstitution of Golgi disassembly by mitotic Xenopus egg extract in semi-intact MDCK cells. Methods Mol Biol 2006; 322:357-65. [PMID: 16739736 DOI: 10.1007/978-1-59745-000-3_25] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Semi-intact cells are cells with plasma membranes that have been permeabilized by bacterial pore-forming toxins or surfactants. The addition of mitotic Xenopus egg extract to semi-intact cells can reconstitute a number of intracellular events that occur specifically at the onset of mitosis. In this chapter, we describe methods for reconstituting the disassembly of the Golgi apparatus by introducing mitotic Xenopus egg extract into semi-intact Mardin-Darby canine kidney (MDCK) cells. The Golgi apparatus was visualized in the cells by expression of green fluorescence protein (GFP)-tagged galactosyltransferase, a marker of trans-Golgi cisternae. Xenopus egg extracts arrested at mitosis or interphase were then prepared and added to the semi-intact MDCK cells. Disassembly of the Golgi apparatus was induced by mitotic Xenopus egg extract. This system can be used not only to elucidate the factors that are involved in the reconstitution process, but also to dissect the process into several elementary steps morphologically and biochemically.
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Affiliation(s)
- Fumi Kano
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Japan
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36
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Subramanian VS, Marchant JS, Said HM. Targeting and trafficking of the human thiamine transporter-2 in epithelial cells. J Biol Chem 2005; 281:5233-45. [PMID: 16371350 DOI: 10.1074/jbc.m512765200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Humans lack biochemical pathways for thiamine synthesis, so cellular requirements are met via specific carrier-mediated uptake pathways. Two proteins from the solute carrier SLC19A gene family have been identified as human thiamine transporters (hTHTRs), SLC19A1 (hTHTR1) and SLC19A2 (hTHTR2). Both of these transporters are co-expressed but are differentially targeted in polarized cell types that mediate vectorial thiamine transport (e.g. renal and intestinal epithelia). It is important to understand the domain structure of these proteins, namely which regions within the polypeptide sequence are important for physiological delivery to the cell surface, in order to understand the impact of clinically relevant mutations on thiamine transport. Here we have characterized the mechanisms regulating hTHTR2 distribution by using live cell imaging methods that resolve the targeting and trafficking dynamics of full-length hTHTR2, a series of hTHTR2 truncation mutants, as well as chimeras comprising the hTHTR1 and hTHTR2 sequence. We showed the following: (i) that the cytoplasmic COOH-tail of hTHTR2 is not essential for apical targeting in polarized cells; (ii) that delivery of hTHTR2 to the cell surface is critically dependent on the integrity of the transmembrane backbone of the polypeptide so that minimal truncations abrogate cell surface expression of hTHTR2; and (iii) video rate images of hTHTR2-containing intracellular vesicles displayed rapid bi-directional trafficking events to and from the cell surface impaired by microtubule-disrupting but not microfilament-disrupting agents as well as by overexpression of the dynactin subunit dynamitin (p50). Finally, we compared the behavior of hTHTR2 with that of hTHTR1 and the human reduced folate carrier (SLC19A1) to underscore commonalities in the cell surface targeting mechanisms of the entire SLC19A gene family.
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37
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Manninen A, Verkade P, Le Lay S, Torkko J, Kasper M, Füllekrug J, Simons K. Caveolin-1 is not essential for biosynthetic apical membrane transport. Mol Cell Biol 2005; 25:10087-96. [PMID: 16260622 PMCID: PMC1280271 DOI: 10.1128/mcb.25.22.10087-10096.2005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Caveolin-1 has been implicated in apical transport of glycosylphosphatidylinositol (GPI)-anchored proteins and influenza virus hemagglutinin (HA). Here we have studied the role of caveolin-1 in apical membrane transport by generating caveolin-1-deficient Madin-Darby canine kidney (MDCK) cells using retrovirus-mediated RNA interference. The caveolin-1 knockdown (cav1-KD) MDCK cells were devoid of caveolae. In addition, caveolin-2 was retained in the Golgi apparatus in cav1-KD MDCK cells. However, we found no significant alterations in the apical transport kinetics of GPI-anchored proteins or HA upon depletion of caveolin-1. Similar results were obtained using embryonic fibroblasts from caveolin-1-knockout mice. Thus, we conclude that caveolin-1 does not play a major role in lipid raft-mediated biosynthetic membrane trafficking.
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Affiliation(s)
- Aki Manninen
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
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38
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Cordo SM, Acuña MCY, Candurra NA. Polarized entry and release of Junin virus, a New World arenavirus. J Gen Virol 2005; 86:1475-1479. [PMID: 15831960 DOI: 10.1099/vir.0.80473-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Junin virus (JUNV), the causative agent of Argentine haemorrhagic fever, is a human pathogen that naturally enters the body through the epithelial cells of the respiratory and digestive tracts. The interaction of JUNV with two types of polarized epithelial cultures, Vero C1008 and A549, was investigated. Radioactive virus-binding assays showed that JUNV infects polarized lines preferentially through the apical surface. High-level expression of viral nucleoprotein was detected in polarized cell lines infected through the apical domain. Virus production from apical media was about 100-fold higher than that found into the basolateral medium. Confocal-immunofluorescence analysis revealed high-level expression of glycoprotein at the apical-membrane surface. Disruption of the microtubule network by colchicine impaired JUNV vectorial release. This is the first study to analyse the interaction between a member of the virus family Arenaviridae and polarized epithelial cells, showing preferential entry and release from the apical plasma membrane.
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Affiliation(s)
- Sandra M Cordo
- Laboratorio de Virología, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria Pab II, CP 1428, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maximiliano Cesio Y Acuña
- Laboratorio de Virología, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria Pab II, CP 1428, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Nélida A Candurra
- Laboratorio de Virología, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria Pab II, CP 1428, Universidad de Buenos Aires, Buenos Aires, Argentina
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39
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Abstract
One of the characteristics of the mammalian Golgi is its position adjacent to the nucleus. This characteristic is maintained through the action of the microtubule (MT) minus end–directed motor dynein and MT-associated proteins (MAPs). Recent findings suggest that GMAP-210, a member of the golgin family of proteins, may help to link Golgi membranes and vesicles with the MT cytoskeleton. However, there are good grounds to doubt that either GMAP-210 or its yeast homologue Rud3p is a MAP. Instead, they appear to function in vesicle trafficking events at the Golgi together with the GTPase ARF1 and a small membrane protein, Erv14. As such, the interesting question of how the Golgi interacts with MTs may well remain open to further investigation.
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Affiliation(s)
- Francis A Barr
- Max-Planck-Institute of Biochemistry, Martinsried, 82152 Germany.
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40
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Abstract
Dynactin is a multisubunit protein complex that is required for most, if not all, types of cytoplasmic dynein activity in eukaryotes. Dynactin binds dynein directly and allows the motor to traverse the microtubule lattice over long distances. A single dynactin subunit, p150Glued, is sufficient for both activities, yet dynactin contains several other subunits that are organized into an elaborate structure. It is currently believed that the bulk of the dynactin structure participates in interactions with a wide range of cellular structures, many of which are cargoes of the dynein motor. Genetic studies verify the importance of all elements of dynactin structure to its function. Although dynein can bind some membranous cargoes independently of dynactin, establishment of a fully functional dynein-cargo link appears to depend on dynactin. In this review, I summarize what is presently known about dynactin structure, the cellular structures with which it associates, and the intermolecular interactions that underlie and regulate binding. Although the molecular details of dynactin's interactions with membranous organelles and other molecules are complex, the framework provided here is intended to distill what is presently known and to be of use to dynactin specialists and beginners alike.
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Affiliation(s)
- Trina A Schroer
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
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41
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Campo C, Mason A, Maouyo D, Olsen O, Yoo D, Welling PA. Molecular mechanisms of membrane polarity in renal epithelial cells. Rev Physiol Biochem Pharmacol 2004; 153:47-99. [PMID: 15674648 DOI: 10.1007/s10254-004-0037-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Exciting discoveries in the last decade have cast light onto the fundamental mechanisms that underlie polarized trafficking in epithelial cells. It is now clear that epithelial cell membrane asymmetry is achieved by a combination of intracellular sorting operations, vectorial delivery mechanisms and plasmalemma-specific fusion and retention processes. Several well-defined signals that specify polarized segregation, sorting, or retention processes have, now, been described in a number of proteins. The intracellular machineries that decode and act on these signals are beginning to be described. In addition, the nature of the molecules that associate with intracellular trafficking vesicles to coordinate polarized delivery, tethering, docking, and fusion are also becoming understood. Combined with direct visualization of polarized sorting processes with new technologies in live-cell fluorescent microscopy, new and surprising insights into these once-elusive trafficking processes are emerging. Here we provide a review of these recent advances within an historically relevant context.
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Affiliation(s)
- C Campo
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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42
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Abstract
Microtubules are essential for many aspects of polarity in multicellular organisms, ranging from the asymmetric distribution of cell-fate determinants in the one-cell embryo to the transient polarity generated in migrating fibroblasts. Epithelial cells exhibit permanent cell polarity characterized by apical and basolateral surface domains of distinct protein and lipid composition that are segregated by tight junctions. They are also endowed with a microtubule network that reflects the asymmetry of their cell surface: microtubule minus-ends face the apical- and microtubule plus-ends the basal domain. Strikingly, the formation of distinct surface domains during epithelial differentiation is accompanied by the re-organization of microtubules from a uniform array focused at the centrosome to the noncentrosomal network that aligns along the apico-basolateral polarity axis. The significance of this coincidence for epithelial morphogenesis and the signaling mechanisms that drive microtubule repolymerization in developing epithelia remain major unresolved questions that we are only beginning to address. Studies in cultured polarized epithelial cells have established that microtubules serve as tracks that facilitate targeted vesicular transport. Novel findings suggest, moreover, that microtubule-based transport promotes protein sorting, and even the generation of transport carriers in the endo- and exocytic pathways.
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Affiliation(s)
- Anne Müsch
- Dyson Institute of Vision Research; Weill Medical College of Cornell University, New York, 10021, USA.
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43
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Marozin S, Prank U, Sodeik B. Herpes simplex virus type 1 infection of polarized epithelial cells requires microtubules and access to receptors present at cell–cell contact sites. J Gen Virol 2004; 85:775-786. [PMID: 15039520 DOI: 10.1099/vir.0.19530-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Mucosal epithelia are invaded from the apical surface during a primary infection by herpes simplex virus type 1 (HSV-1). HSV-1 progeny virus, synthesized from latently infected peripheral neurons that innervate such epithelia, reinfects the epithelia most likely from the basolateral surface. The epithelial cell lines MDCK and Caco-2 can be inducedin vitroto differentiate into polarized cells with distinct apical and plasma membrane domains separated by tight junctions if they are cultured on porous membrane filters. Our data using these culture systems showed that highly polarized epithelial cells were not susceptible to apical HSV-1 infection. However, HSV-1 infected these cells if added from the basolateral surface or if a depletion of extracellular Ca2+had weakened the strength of the cell–cell contacts. Basolateral infection and apical infection after the Ca2+switch required an intact microtubule network for genome targeting to the nucleus. This system can be used to identify the microtubule motors that HSV-1 uses during virus entry in polarized epithelial cells.
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Affiliation(s)
- Sabrina Marozin
- Department of Virology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30623 Hannover, Germany
| | - Ute Prank
- Department of Virology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30623 Hannover, Germany
| | - Beate Sodeik
- Department of Virology, Hannover Medical School, Carl-Neuberg-Str. 1, D-30623 Hannover, Germany
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44
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van der Wouden JM, Maier O, van IJzendoorn SCD, Hoekstra D. Membrane dynamics and the regulation of epithelial cell polarity. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 226:127-64. [PMID: 12921237 DOI: 10.1016/s0074-7696(03)01003-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Plasma membranes of epithelial cells consist of two domains, an apical and a basolateral domain, the surfaces of which differ in composition. The separation of these domains by a tight junction and the fact that specific transport pathways exist for intracellular communication between these domains and distinct intracellular compartments relevant to cell polarity development, have triggered extensive research on issues that focus on how the polarity is generated and maintained. Apart from proper assembly of tight junctions, their potential functioning as landmark for the transport machinery, cell-cell adhesion is obviously instrumental in barrier formation. In recent years, distinct endocytic compartments, defined as subapical compartment or common endosome, were shown to play a prominent role in regulating membrane trafficking to and from polarized membrane domains. Sorting devices remain to be determined but likely include distinct rab proteins, and evidence is accumulating to indicate that signaling events may direct intracellular membrane transport, intimately involved in the biogenesis and maintenance of polarized membrane domains and hence the development of cell polarity.
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Affiliation(s)
- Johanna M van der Wouden
- Department of Membrane Cell Biology, University of Groningen, Antonius Deusinglaan 1, 9713AV Groningen, The Netherlands
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45
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Andersson I, Simon M, Lundkvist A, Nilsson M, Holmström A, Elgh F, Mirazimi A. Role of actin filaments in targeting of Crimean Congo hemorrhagic fever virus nucleocapsid protein to perinuclear regions of mammalian cells. J Med Virol 2004; 72:83-93. [PMID: 14635015 DOI: 10.1002/jmv.10560] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Crimean-Congo hemorrhagic fever virus is the causative agent of a severe disease throughout Africa, Europe, and Asia. Like other members of the genus Nairovirus, the Crimean-Congo hemorrhagic fever virus contains three genomic RNA segments, the small (S), medium (M), and large (L) segments. The S segment encodes the viral nucleocapsid protein (NP), while the M and L segments encode the glycoproteins and the RNA-dependent RNA polymerase, respectively. In this study, the site of expression and assembly of Crimean-Congo hemorrhagic fever virus NP in mammalian cells have been investigated. It was found that the NP is localized in the perinuclear region of infected cells. By using the Semliki forest virus expression system, it was shown that the Crimean-Congo hemorrhagic fever virus NP is targeted to the perinuclear region of cells in the absence of native RNA segments and virally encoded glycoproteins. It was also demonstrated that the Crimean-Congo hemorrhagic fever virus NP was not expressed as a Golgi-membrane associated protein. By using Cytochalasin D, an agent that disrupts actin filaments, it was found that actin filaments are involved in targeting the viral NP to perinuclear regions. We also demonstrated that disruption of actin filaments reduced the assembly of infectious Crimean-Congo hemorrhagic fever virus up to 97%. Furthermore, we showed that the NP of Crimean-Congo hemorrhagic fever virus NP interacts with actin.
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Affiliation(s)
- Ida Andersson
- Center for Microbiological Preparedness,Swedish Institute for Infectious Disease Control, SE Solna, Sweden
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46
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Abstract
During embryonic development, polarized epithelial cells are either formed during cleavage or formed from mesenchymal cells. Because the formation of epithelia during embryogenesis has to occur with high fidelity to ensure proper development, embryos allow a functional approach to study epithelial cell polarization in vivo. In particular, genetic model organisms have greatly advanced our understanding of the generation and maintenance of epithelial cell polarity. Many novel and important polarity genes have been identified and characterized in invertebrate systems, like Drosophila melanogaster and Caenorhabditis elegans. With the rapid identification of mammalian homologues of these invertebrate polarity genes, it has become clear that many important protein domains, single proteins and even entire protein complexes are evolutionarily conserved. It is to be expected that the field of epithelial cell polarity is just experiencing the 'top of the iceberg' of a large protein network that is fundamental for the specific adhesive, cell signalling and transport functions of epithelial cells.
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Affiliation(s)
- H-Arno J Müller
- Institut für Genetik, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, Düsseldorf D-40225, Germany.
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47
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Wald FA, Figueroa Y, Oriolo AS, Salas PJI. Membrane repolarization is delayed in proximal tubules after ischemia-reperfusion: possible role of microtubule-organizing centers. Am J Physiol Renal Physiol 2003; 285:F230-40. [PMID: 12709392 DOI: 10.1152/ajprenal.00024.2003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We have previously shown that microtubule-organizing centers (MTOCs) attach to the apical network of intermediate filaments (IFs) in epithelial cells in culture and in epithelia in vivo. Because that attachment is important for the architecture of microtubules (MTs) in epithelia, we analyzed whether chemical anoxia in LLC-PK1 and CACO-2 cells or unilateral ischemia-reperfusion in rat kidney (performed under fluorane anesthesia) had an effect on the binding and distribution of MTOCs. In culture, we found that chemical anoxia induces MTOC detachment from IFs by morphological and biochemical criteria. In reperfused rat proximal tubules, noncentrosomal MTOCs were fully detached from the cytoskeleton and scattered throughout the cytoplasm at 3 days after reperfusion, when brush borders were mostly reassembled. At that time, MTs were also fully reassembled but, as expected, lacked their normal apicobasal orientation. Two apical membrane markers expressed in S2 and S3 segments were depolarized at the same stage. At 8 days after reperfusion, membrane polarity, MTOCs, and MTs were back to normal. Na+-K+-ATPase was also found redistributed, not to the apical domain but rather to an intracellular compartment, as described by others (Alejandro VS, Nelson W, Huie P, Sibley RK, Dafoe D, Kuo P, Scandling JD Jr., and Myers BD. Kidney Int 48: 1308-1315, 1995). The prolonged depolarization of the apical membrane may have implications in the pathophysiology of acute renal failure.
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Affiliation(s)
- Flavia A Wald
- Department of Cell Biology and Anatomy, University of Miami School of Medicine, 1600 NW 10th Ave., Miami, FL 33136, USA
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48
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Abstract
Transcytosis, the vesicular transport of macromolecules from one side of a cell to the other, is a strategy used by multicellular organisms to selectively move material between two environments without altering the unique compositions of those environments. In this review, we summarize our knowledge of the different cell types using transcytosis in vivo, the variety of cargo moved, and the diverse pathways for delivering that cargo. We evaluate in vitro models that are currently being used to study transcytosis. Caveolae-mediated transcytosis by endothelial cells that line the microvasculature and carry circulating plasma proteins to the interstitium is explained in more detail, as is clathrin-mediated transcytosis of IgA by epithelial cells of the digestive tract. The molecular basis of vesicle traffic is discussed, with emphasis on the gaps and uncertainties in our understanding of the molecules and mechanisms that regulate transcytosis. In our view there is still much to be learned about this fundamental process.
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Affiliation(s)
- Pamela L Tuma
- Hunterian 119, Department of Cell Biology, 725 N Wolfe St, Baltimore, MD 21205, USA
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49
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Nagata KI, Kawajiri A, Matsui S, Takagishi M, Shiromizu T, Saitoh N, Izawa I, Kiyono T, Itoh TJ, Hotani H, Inagaki M. Filament formation of MSF-A, a mammalian septin, in human mammary epithelial cells depends on interactions with microtubules. J Biol Chem 2003; 278:18538-43. [PMID: 12626509 DOI: 10.1074/jbc.m205246200] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Septins are a family of conserved proteins implicated in a variety of cellular functions such as cytokinesis and vesicle trafficking, but their properties and modes of action are largely unknown. Here we now report findings of immunocytochemical and biochemical characterization of a mammalian septin, MSF-A. Using an antibody specific for MSF subfamily proteins, MSF-A was found to be expressed predominantly in mammary human mammary epithelial cells (HMEC). MSF-A was associated with microtubules in interphase HMEC cells as it localized with the mitotic spindle and the bundle of microtubule at midzone during mitosis. Biochemical analysis revealed direct binding of MSF-A with polymerized tubulin through its central region containing guanine nucleotide-interactive motifs. GTPase activity, however, was not required for the association. Conditions that disrupt the microtubule network also disrupted the MSF-A-containing filament structure, resulting in a punctate cytoplasmic pattern. Depletion of MSF-A using small interfering RNAs caused incomplete cell division and resulted in the accumulation of binucleated cells. Unlike Nedd5, an MSF mutant deficient in GTPase activity forms filament indistinguishable from that of the wild type in COS cells. These results strongly suggest that septin filaments may interact not only with actin filaments but also with microtubule networks and that GTPase activity of MSF-A is not indispensable to incorporation of MSF-A into septin filaments.
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Affiliation(s)
- Koh-Ichi Nagata
- Divisions of Biochemistry and Virology, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya 464-8681, Japan
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50
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Hoekstra D, Maier O, van der Wouden JM, Slimane TA, van IJzendoorn SCD. Membrane dynamics and cell polarity: the role of sphingolipids. J Lipid Res 2003; 44:869-77. [PMID: 12639977 DOI: 10.1194/jlr.r300003-jlr200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In recent years, glycosphingolipids (GSLs) have attracted widespread attention due to the appreciation that this class of lipids has a major impact on biological life. Inhibition of the synthesis of glucosylceramide, which serves as a precursor for the generation of complex glycosphinglipids, is embryonic lethal. GSLs play a major role in growth and development. Metabolites of sphingolipids, such as ceramide, sphinganine, and sphingosine, may function as second messengers or regulators of signal transduction that affect events ranging from apoptosis to the (co)regulation of the cell cycle. In addition, GSLs can provide a molecular platform for clustering of signal transducers. The ability of sphingolipids, with or without cholesterol, to form microdomains or rafts is critical in sorting and membrane transport that underlies the biogenesis of polarized membrane domains. Here, a brief summary is presented of some recent developments in this field, with a particular emphasis on raft assembly and membrane transport in the establishment of membrane polarity.
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Affiliation(s)
- Dick Hoekstra
- University of Groningen, Department of Membrane Cell Biology, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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