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Herrnberger L, Hennig R, Kremer W, Hellerbrand C, Goepferich A, Kalbitzer HR, Tamm ER. Formation of fenestrae in murine liver sinusoids depends on plasmalemma vesicle-associated protein and is required for lipoprotein passage. PLoS One 2014; 9:e115005. [PMID: 25541982 PMCID: PMC4277272 DOI: 10.1371/journal.pone.0115005] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 11/17/2014] [Indexed: 12/11/2022] Open
Abstract
Liver sinusoidal endothelial cells (LSEC) are characterized by the presence of fenestrations that are not bridged by a diaphragm. The molecular mechanisms that control the formation of the fenestrations are largely unclear. Here we report that mice, which are deficient in plasmalemma vesicle-associated protein (PLVAP), develop a distinct phenotype that is caused by the lack of sinusoidal fenestrations. Fenestrations with a diaphragm were not observed in mouse LSEC at three weeks of age, but were present during embryonic life starting from embryonic day 12.5. PLVAP was expressed in LSEC of wild-type mice, but not in that of Plvap-deficient littermates. Plvap-/- LSEC showed a pronounced and highly significant reduction in the number of fenestrations, a finding, which was seen both by transmission and scanning electron microscopy. The lack of fenestrations was associated with an impaired passage of macromolecules such as FITC-dextran and quantum dot nanoparticles from the sinusoidal lumen into Disse's space. Plvap-deficient mice suffered from a pronounced hyperlipoproteinemia as evidenced by milky plasma and the presence of lipid granules that occluded kidney and liver capillaries. By NMR spectroscopy of plasma, the nature of hyperlipoproteinemia was identified as massive accumulation of chylomicron remnants. Plasma levels of low density lipoproteins (LDL) were also significantly increased as were those of cholesterol and triglycerides. In contrast, plasma levels of high density lipoproteins (HDL), albumin and total protein were reduced. At around three weeks of life, Plvap-deficient livers developed extensive multivesicular steatosis, steatohepatitis, and fibrosis. PLVAP is critically required for the formation of fenestrations in LSEC. Lack of fenestrations caused by PLVAP deficiency substantially impairs the passage of chylomicron remnants between liver sinusoids and hepatocytes, and finally leads to liver damage.
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Affiliation(s)
- Leonie Herrnberger
- Department of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Robert Hennig
- Department of Pharmaceutical Technology, University of Regensburg, Regensburg, Germany
| | - Werner Kremer
- Department of Biophysics and Physical Biochemistry, and Centre of Magnetic Resonance in Chemistry and Biomedicine, University of Regensburg, Regensburg, Germany
| | - Claus Hellerbrand
- Department of Internal Medicine I, University Hospital Regensburg, Regensburg, Germany
| | - Achim Goepferich
- Department of Pharmaceutical Technology, University of Regensburg, Regensburg, Germany
| | - Hans Robert Kalbitzer
- Department of Biophysics and Physical Biochemistry, and Centre of Magnetic Resonance in Chemistry and Biomedicine, University of Regensburg, Regensburg, Germany
| | - Ernst R. Tamm
- Department of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
- * E-mail:
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152
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Bill BR, Korzh V. Choroid plexus in developmental and evolutionary perspective. Front Neurosci 2014; 8:363. [PMID: 25452709 PMCID: PMC4231874 DOI: 10.3389/fnins.2014.00363] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 10/22/2014] [Indexed: 01/17/2023] Open
Abstract
The blood-cerebrospinal fluid boundary is present at the level of epithelial cells of the choroid plexus. As one of the sources of the cerebrospinal fluid (CSF), the choroid plexus (CP) plays an important role during brain development and function. Its formation has been studied largely in mammalian species. Lately, progress in other model animals, in particular the zebrafish, has brought a deeper understanding of CP formation, due in part to the ability to observe CP development in vivo. At the same time, advances in comparative genomics began providing information, which opens a possibility to understand further the molecular mechanisms involved in evolution of the CP and the blood-cerebrospinal fluid boundary formation. Hence this review focuses on analysis of the CP from developmental and evolutionary perspectives.
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Affiliation(s)
- Brent Roy Bill
- Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles Los Angeles, CA, USA
| | - Vladimir Korzh
- Agency for Science, Technology and Research of Singapore, Institute of Molecular and Cell Biology Singapore, Singapore ; National University of Singapore, Department of Biological Sciences Singapore, Singapore
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153
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Liu J, Deutsch U, Fung I, Lobe CG. Conditional and inducible transgene expression in endothelial and hematopoietic cells using Cre/ loxP and tetracycline-off systems. Exp Ther Med 2014; 8:1351-1356. [PMID: 25289022 PMCID: PMC4186360 DOI: 10.3892/etm.2014.1965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 08/05/2014] [Indexed: 01/25/2023] Open
Abstract
In the present study, the tetracycline-off and Cre/loxP systems were combined to gain temporal and spatial control of transgene expression. Mice were generated that carried three transgenes: Tie2-tTA, tet-O-Cre and either the ZEG or ZAP reporter. Tie2-tTA directs expression of tetracycline-controlled transactivator (tTA) in endothelial and hematopoietic cells under the control of the Tie2 promoter. Tet-O-Cre produces Cre recombinase from a minimal promoter containing the tet-operator (tetO). ZEG or ZAP contains a strong promoter and a loxP-flanked stop sequence, followed by an enhanced green fluorescence protein (EGFP) or human placental alkaline phosphatase (hPLAP) reporter. In the presence of tetracycline, the tTA transactivator produced by Tie-2-tTA is disabled and Cre is not expressed. In the absence of tetracycline, the tTA binds tet-O-Cre to drive the expression of Cre, which recombines the loxP sites of the ZEG or ZAP transgene and results in reporter gene expression. In the present study, the expression of the ZEG or ZAP reporter genes in embryos and adult animals with and without tetracycline treatment was examined. In the presence of tetracycline, no reporter gene expression was observed. When tetracycline was withdrawn, Cre excision was activated and the reporter genes were detected in endothelial and hematopoietic cells. These results demonstrate that this system may be used to bypass embryonic lethality and access adult phenotypes.
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Affiliation(s)
- Ju Liu
- Laboratory of Microvascular Medicine, Medical Research Center, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, Shandong 250014, P.R. China ; Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, Toronto, Ontario M4N 3M5, Canada ; Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Urban Deutsch
- Theodor-Kocher-Institute, University of Berne, Berne CH-3012, Switzerland
| | - Iris Fung
- Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, Toronto, Ontario M4N 3M5, Canada ; Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
| | - Corrinne G Lobe
- Molecular and Cellular Biology Division, Sunnybrook Health Science Centre, Toronto, Ontario M4N 3M5, Canada ; Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada
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154
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Sriraman SK, Aryasomayajula B, Torchilin VP. Barriers to drug delivery in solid tumors. Tissue Barriers 2014; 2:e29528. [PMID: 25068098 PMCID: PMC4106925 DOI: 10.4161/tisb.29528] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/06/2014] [Accepted: 06/09/2014] [Indexed: 02/07/2023] Open
Abstract
Over the last decade, significant progress has been made in the field of drug delivery. The advent of engineered nanoparticles has allowed us to circumvent the initial limitations to drug delivery such as pharmacokinetics and solubility. However, in spite of significant advances to tumor targeting, an effective treatment strategy for malignant tumors still remains elusive. Tumors possess distinct physiological features which allow them to resist traditional treatment approaches. This combined with the complexity of the biological system presents significant hurdles to the site-specific delivery of therapeutic drugs. One of the key features of engineered nanoparticles is that these can be tailored to execute specific functions. With this review, we hope to provide the reader with a clear understanding and knowledge of biological barriers and the methods to exploit these characteristics to design multifunctional nanocarriers, effect useful dosing regimens and subsequently improve therapeutic outcomes in the clinic.
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Affiliation(s)
- Shravan Kumar Sriraman
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
| | - Bhawani Aryasomayajula
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
| | - Vladimir P Torchilin
- Center for Pharmaceutical Biotechnology and Nanomedicine; Northeastern University; Boston, MA USA
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155
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Shvets E, Ludwig A, Nichols BJ. News from the caves: update on the structure and function of caveolae. Curr Opin Cell Biol 2014; 29:99-106. [PMID: 24908346 DOI: 10.1016/j.ceb.2014.04.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/03/2014] [Accepted: 04/24/2014] [Indexed: 10/25/2022]
Abstract
Recent data from the study of the cell biology of caveolae have provided insights both into how these flask-shaped invaginations of the plasma membrane are formed and how they may function in different contexts. This review discusses experiments that analyse the composition and ultrastructural distribution of protein complexes responsible for generating caveolae, that suggest functions for caveolae in response to mechanical stress or damage to the plasma membrane, that show that caveolae may have an important role during the signalling events for regulation of metabolism, and that imply that caveolae can act as endocytic vesicles at the plasma membrane. We also highlight unexpected roles for caveolar proteins in regulating circadian rhythms and new insights into the way in which caveolae may be involved in fatty acid uptake in the intestine. Current outstanding questions in the field are emphasised.
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Affiliation(s)
| | - Alexander Ludwig
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
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156
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Howard M, Zern BJ, Anselmo AC, Shuvaev VV, Mitragotri S, Muzykantov V. Vascular targeting of nanocarriers: perplexing aspects of the seemingly straightforward paradigm. ACS NANO 2014; 8:4100-32. [PMID: 24787360 PMCID: PMC4046791 DOI: 10.1021/nn500136z] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 04/30/2014] [Indexed: 05/18/2023]
Abstract
Targeted nanomedicine holds promise to find clinical use in many medical areas. Endothelial cells that line the luminal surface of blood vessels represent a key target for treatment of inflammation, ischemia, thrombosis, stroke, and other neurological, cardiovascular, pulmonary, and oncological conditions. In other cases, the endothelium is a barrier for tissue penetration or a victim of adverse effects. Several endothelial surface markers including peptidases (e.g., ACE, APP, and APN) and adhesion molecules (e.g., ICAM-1 and PECAM) have been identified as key targets. Binding of nanocarriers to these molecules enables drug targeting and subsequent penetration into or across the endothelium, offering therapeutic effects that are unattainable by their nontargeted counterparts. We analyze diverse aspects of endothelial nanomedicine including (i) circulation and targeting of carriers with diverse geometries, (ii) multivalent interactions of carrier with endothelium, (iii) anchoring to multiple determinants, (iv) accessibility of binding sites and cellular response to their engagement, (v) role of cell phenotype and microenvironment in targeting, (vi) optimization of targeting by lowering carrier avidity, (vii) endocytosis of multivalent carriers via molecules not implicated in internalization of their ligands, and (viii) modulation of cellular uptake and trafficking by selection of specific epitopes on the target determinant, carrier geometry, and hydrodynamic factors. Refinement of these aspects and improving our understanding of vascular biology and pathology is likely to enable the clinical translation of vascular endothelial targeting of nanocarriers.
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Affiliation(s)
- Melissa Howard
- Center for Targeted Therapeutics and Translational Nanomedicine, Institute for Translational Medicine & Therapeutics and Department of Pharmacology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
| | - Blaine J. Zern
- Center for Targeted Therapeutics and Translational Nanomedicine, Institute for Translational Medicine & Therapeutics and Department of Pharmacology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
| | - Aaron C. Anselmo
- Department of Chemical Engineering, Center for Bioengineering, University of California, Santa Barbara, California 93106, United States
| | - Vladimir V. Shuvaev
- Center for Targeted Therapeutics and Translational Nanomedicine, Institute for Translational Medicine & Therapeutics and Department of Pharmacology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
| | - Samir Mitragotri
- Department of Chemical Engineering, Center for Bioengineering, University of California, Santa Barbara, California 93106, United States
| | - Vladimir Muzykantov
- Center for Targeted Therapeutics and Translational Nanomedicine, Institute for Translational Medicine & Therapeutics and Department of Pharmacology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania 19104, United States
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157
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Warnock DG, Kusche-Vihrog K, Tarjus A, Sheng S, Oberleithner H, Kleyman TR, Jaisser F. Blood pressure and amiloride-sensitive sodium channels in vascular and renal cells. Nat Rev Nephrol 2014; 10:146-57. [PMID: 24419567 DOI: 10.1038/nrneph.2013.275] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sodium transport in the distal nephron is mediated by epithelial sodium channel activity. Proteolytic processing of external domains and inhibition with increased sodium concentrations are important regulatory features of epithelial sodium channel complexes expressed in the distal nephron. By contrast, sodium channels expressed in the vascular system are activated by increased external sodium concentrations, which results in changes in the mechanical properties and function of endothelial cells. Mechanosensitivity and shear stress affect both epithelial and vascular sodium channel activity. Guyton's hypothesis stated that blood pressure control is critically dependent on vascular tone and fluid handling by the kidney. The synergistic effects, and complementary regulation, of the epithelial and vascular systems are consistent with the Guytonian model of volume and blood pressure regulation, and probably reflect sequential evolution of the two systems. The integration of vascular tone, renal perfusion and regulation of renal sodium reabsorption is the central underpinning of the Guytonian model. In this Review, we focus on the expression and regulation of sodium channels, and we outline the emerging evidence that describes the central role of amiloride-sensitive sodium channels in the efferent (vascular) and afferent (epithelial) arms of this homeostatic system.
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Affiliation(s)
- David G Warnock
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, 1720 2nd Avenue South, Birmingham, AL 34294-0007, USA
| | - Kristina Kusche-Vihrog
- Institut für Physiologie II, Westfälische Wilhelms Universität, Robert-Koch-Straße 27, 48149 Münster, Germany
| | - Antoine Tarjus
- INSERM U872 Team 1, Centre de Recherche des Cordeliers, Université René Descartes, Université Pierre et Marie Curie, 15 rue de l'Ecole de Médecine, 75006 Paris, France
| | - Shaohu Sheng
- Renal and Electrolyte Division, Department of Medicine, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA 15261, USA
| | - Hans Oberleithner
- Institut für Physiologie II, Westfälische Wilhelms Universität, Robert-Koch-Straße 27, 48149 Münster, Germany
| | - Thomas R Kleyman
- Renal and Electrolyte Division, Department of Medicine, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA 15261, USA
| | - Frederic Jaisser
- INSERM U872 Team 1, Centre de Recherche des Cordeliers, Université René Descartes, Université Pierre et Marie Curie, 15 rue de l'Ecole de Médecine, 75006 Paris, France
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158
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Deletion of cavin genes reveals tissue-specific mechanisms for morphogenesis of endothelial caveolae. Nat Commun 2013; 4:1831. [PMID: 23652019 PMCID: PMC3674239 DOI: 10.1038/ncomms2808] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 03/26/2013] [Indexed: 12/23/2022] Open
Abstract
Caveolae are abundant in endothelial cells and are thought to have important roles in endothelial cell biology. The cavin proteins are key components of caveolae, and are expressed at varied amounts in different tissues. Here we use knockout mice to determine the roles of cavins 2 and 3 in caveolar morphogenesis in vivo. Deletion of cavin 2 causes loss of endothelial caveolae in lung and adipose tissue, but has no effect on the abundance of endothelial caveolae in heart and other tissues. Changes in the morphology of endothelium in cavin 2 null mice correlate with changes in caveolar abundance. Cavin 3 is not required for making caveolae in the tissues examined. Cavin 2 determines the size of cavin complexes, and acts to shape caveolae. Cavin 1, however, is essential for normal oligomerization of caveolin 1. Our data reveal that endothelial caveolae are heterogeneous, and identify cavin 2 as a determinant of this heterogeneity. Cavin proteins are key components of mammalian caveolae and are expressed from four genes in a tissue-specific manner. Gram Hansen et al. demonstrate that caveolae in the endothelia of different tissues are remarkably heterogeneous, and reveal a role for cavin 2 in determining the apparent size of cavin complexes.
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159
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Tichauer KM, Deharvengt SJ, Samkoe KS, Gunn JR, Bosenberg MW, Turk MJ, Hasan T, Stan RV, Pogue BW. Tumor endothelial marker imaging in melanomas using dual-tracer fluorescence molecular imaging. Mol Imaging Biol 2013; 16:372-82. [PMID: 24217944 DOI: 10.1007/s11307-013-0692-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 09/05/2013] [Accepted: 09/19/2013] [Indexed: 12/28/2022]
Abstract
PURPOSE Cancer-specific endothelial markers available for intravascular binding are promising targets for new molecular therapies. In this study, a molecular imaging approach of quantifying endothelial marker concentrations (EMCI) is developed and tested in highly light-absorbing melanomas. The approach involves injection of targeted imaging tracer in conjunction with an untargeted tracer, which is used to account for nonspecific uptake and tissue optical property effects on measured targeted tracer concentrations. PROCEDURES Theoretical simulations and a mouse melanoma model experiment were used to test out the EMCI approach. The tracers used in the melanoma experiments were fluorescently labeled anti-Plvap/PV1 antibody (plasmalemma vesicle associated protein Plvap/PV1 is a transmembrane protein marker exposed on the luminal surface of endothelial cells in tumor vasculature) and a fluorescent isotype control antibody, the uptakes of which were measured on a planar fluorescence imaging system. RESULTS The EMCI model was found to be robust to experimental noise under reversible and irreversible binding conditions and was capable of predicting expected overexpression of PV1 in melanomas compared to healthy skin despite a 5-time higher measured fluorescence in healthy skin compared to melanoma: attributable to substantial light attenuation from melanin in the tumors. CONCLUSIONS This study demonstrates the potential of EMCI to quantify endothelial marker concentrations in vivo, an accomplishment that is currently unavailable through any other methods, either in vivo or ex vivo.
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Affiliation(s)
- Kenneth M Tichauer
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, 60616, USA,
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160
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Cogger VC, Roessner U, Warren A, Fraser R, Le Couteur DG. A Sieve-Raft Hypothesis for the regulation of endothelial fenestrations. Comput Struct Biotechnol J 2013; 8:e201308003. [PMID: 24688743 PMCID: PMC3962122 DOI: 10.5936/csbj.201308003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 07/31/2013] [Accepted: 08/11/2013] [Indexed: 01/13/2023] Open
Affiliation(s)
- Victoria C Cogger
- Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney NSW, Australia ; Charles Perkins Centre, University of Sydney NSW Australia
| | - Ute Roessner
- Metabolomics Australia and Australian Centre for Plant Functional Genomics, The University of Melbourne, 3010 Victoria, Australia
| | - Alessandra Warren
- Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney NSW, Australia ; Charles Perkins Centre, University of Sydney NSW Australia
| | - Robin Fraser
- Christchurch School of Medicine, University of Otago, Christchurch NZ
| | - David G Le Couteur
- Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney NSW, Australia ; Charles Perkins Centre, University of Sydney NSW Australia
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161
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Tkachenko E, Tse D, Sideleva O, Deharvengt SJ, Luciano MR, Xu Y, McGarry CL, Chidlow J, Pilch PF, Sessa WC, Toomre DK, Stan RV. Caveolae, fenestrae and transendothelial channels retain PV1 on the surface of endothelial cells. PLoS One 2012; 7:e32655. [PMID: 22403691 PMCID: PMC3293851 DOI: 10.1371/journal.pone.0032655] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 01/28/2012] [Indexed: 11/21/2022] Open
Abstract
PV1 protein is an essential component of stomatal and fenestral diaphragms, which are formed at the plasma membrane of endothelial cells (ECs), on structures such as caveolae, fenestrae and transendothelial channels. Knockout of PV1 in mice results in in utero and perinatal mortality. To be able to interpret the complex PV1 knockout phenotype, it is critical to determine whether the formation of diaphragms is the only cellular role of PV1. We addressed this question by measuring the effect of complete and partial removal of structures capable of forming diaphragms on PV1 protein level. Removal of caveolae in mice by knocking out caveolin-1 or cavin-1 resulted in a dramatic reduction of PV1 protein level in lungs but not kidneys. The magnitude of PV1 reduction correlated with the abundance of structures capable of forming diaphragms in the microvasculature of these organs. The absence of caveolae in the lung ECs did not affect the transcription or translation of PV1, but it caused a sharp increase in PV1 protein internalization rate via a clathrin- and dynamin-independent pathway followed by degradation in lysosomes. Thus, PV1 is retained on the cell surface of ECs by structures capable of forming diaphragms, but undergoes rapid internalization and degradation in the absence of these structures, suggesting that formation of diaphragms is the only role of PV1.
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Affiliation(s)
- Eugene Tkachenko
- Department of Medicine, University of California, San Diego, California, United States of America
| | - Dan Tse
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- Heart and Vascular Research Center, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - Olga Sideleva
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - Sophie J. Deharvengt
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - Marcus R. Luciano
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - Yan Xu
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - Caitlin L. McGarry
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- Heart and Vascular Research Center, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
| | - John Chidlow
- Department of Pharmacology, Yale University, New Haven, Connecticut, United States of America
| | - Paul F. Pilch
- Department of Biochemistry, Boston University, Boston, Massachusetts, United States of America
| | - William C. Sessa
- Department of Pharmacology, Yale University, New Haven, Connecticut, United States of America
| | - Derek K. Toomre
- Department of Cell Biology, Yale University, New Haven, Connecticut, United States of America
| | - Radu V. Stan
- Department of Pathology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- Heart and Vascular Research Center, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- Norris Cotton Cancer Center, Dartmouth Medical School, Lebanon, New Hampshire, United States of America
- * E-mail:
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