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Jerrold R Turner - One of the best experts on this subject based on the ideXlab platform.
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cell biology of Tight Junction barrier regulation and mucosal disease
Cold Spring Harbor Perspectives in Biology, 2018Co-Authors: Aaron Buckley, Jerrold R TurnerAbstract:Mucosal surfaces are lined by epithelial cells. In the intestine, the epithelium establishes a selectively permeable barrier that supports nutrient absorption and waste secretion while preventing intrusion by luminal materials. Intestinal epithelia therefore play a central role in regulating interactions between the mucosal immune system and luminal contents, which include dietary antigens, a diverse intestinal microbiome, and pathogens. The paracellular space is sealed by the Tight Junction, which is maintained by a complex network of protein interactions. Tight Junction dysfunction has been linked to a variety of local and systemic diseases. Two molecularly and biophysically distinct pathways across the intestinal Tight Junction are selectively and differentially regulated by inflammatory stimuli. This review discusses the mechanisms underlying these events, their impact on disease, and the potential of using these as paradigms for development of Tight Junction-targeted therapeutic interventions.
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myosin light chain kinase pulling the strings of epithelial Tight Junction function
Annals of the New York Academy of Sciences, 2012Co-Authors: Kevin E Cunningham, Jerrold R TurnerAbstract:Dynamic regulation of paracellular permeability is essential for physiological epithelial function, while dysregulated permeability is common in disease. The recent elucidation of the molecular composition of the epithelial Tight Junction complex has been accompanied by characterization of diverse intracellular mediators of paracellular permeabiltiy. Myosin light chain kinase, which induces contraction of the periJunctional actomyosin ring through myosin II regulatory light chain phosphorylation, has emerged as a key regulator of Tight Junction permeability. Examination of the regulation and role of MLCK in Tight Junction dysfunction has helped to define pathological processes, characterize the role of barrier loss in disease pathogenesis, and may provide future therapeutic targets to treat intestinal disease.
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epithelial myosin light chain kinase activation induces mucosal interleukin 13 expression to alter Tight Junction ion selectivity
Journal of Biological Chemistry, 2010Co-Authors: Christopher R Weber, Le Shen, David R Raleigh, Yingmin Wang, Liping Su, Erika A Sullivan, Jerrold R TurnerAbstract:Intestinal barrier function is reduced in inflammatory bowel disease (IBD). Tumor necrosis factor (TNF) and interleukin (IL)-13, which are up-regulated in IBD, induce barrier defects that are associated with myosin light chain kinase (MLCK) activation and increased claudin-2 expression, respectively, in cultured intestinal epithelial monolayers. Here we report that these independent signaling pathways have distinct effects on Tight Junction barrier properties and interact in vivo. MLCK activation alters size selectivity to enhance paracellular flux of uncharged macromolecules without affecting charge selectivity and can be rapidly reversed by MLCK inhibition. In contrast, IL-13-dependent claudin-2 expression increases paracellular cation flux in vitro and in vivo without altering Tight Junction size selectivity but is unaffected by MLCK inhibition in vitro. In vivo, MLCK activation increases paracellular flux of uncharged macromolecules and also triggers IL-13 expression, claudin-2 synthesis, and increased paracellular cation flux. We conclude that reversible, MLCK-dependent permeability increases cause mucosal immune activation that, in turn, feeds back on the Tight Junction to establish long-lasting barrier defects. Interactions between these otherwise distinct Tight Junction regulatory pathways may contribute to IBD pathogenesis.
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Tight Junction associated marvel proteins marveld3 tricellulin and occludin have distinct but overlapping functions
Molecular Biology of the Cell, 2010Co-Authors: David R Raleigh, Le Shen, Amanda M Marchiando, Yong Zhang, Hiroyuki Sasaki, Yingmin Wang, Manyuan Long, Jerrold R TurnerAbstract:In vitro studies have demonstrated that occludin and tricellulin are important for Tight Junction barrier function, but in vivo data suggest that loss of these proteins can be overcome. The presence of a heretofore unknown, yet related, protein could explain these observations. Here, we report marvelD3, a novel Tight Junction protein that, like occludin and tricellulin, contains a conserved four-transmembrane MARVEL (MAL and related proteins for vesicle trafficking and membrane link) domain. Phylogenetic tree reconstruction; analysis of RNA and protein tissue distribution; immunofluorescent and electron microscopic examination of subcellular localization; characterization of intracellular trafficking, protein interactions, dynamic behavior, and siRNA knockdown effects; and description of remodeling after in vivo immune activation show that marvelD3, occludin, and tricellulin have distinct but overlapping functions at the Tight Junction. Although marvelD3 is able to partially compensate for occludin or tricellulin loss, it cannot fully restore function. We conclude that marvelD3, occludin, and tricellulin define the Tight Junction–associated MARVEL protein family. The data further suggest that these proteins are best considered as a group with both redundant and unique contributions to epithelial function and Tight Junction regulation.
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the Tight Junction protein complex undergoes rapid and continuous molecular remodeling at steady state
Journal of Cell Biology, 2008Co-Authors: Le Shen, Christopher R Weber, Jerrold R TurnerAbstract:The Tight Junction defines epithelial organization. Structurally, the Tight Junction is comprised of transmembrane and membrane-associated proteins that are thought to assemble into stable complexes to determine function. In this study, we measure Tight Junction protein dynamics in live confluent Madin–Darby canine kidney monolayers using fluorescence recovery after photobleaching and related methods. Mathematical modeling shows that the majority of claudin-1 (76 ± 5%) is stably localized at the Tight Junction. In contrast, the majority of occludin (71 ± 3%) diffuses rapidly within the Tight Junction with a diffusion constant of 0.011 μm2s−1. Zonula occludens-1 molecules are also highly dynamic in this region, but, rather than diffusing within the plane of the membrane, 69 ± 5% exchange between membrane and intracellular pools in an energy-dependent manner. These data demonstrate that the Tight Junction undergoes constant remodeling and suggest that this dynamic behavior may contribute to Tight Junction assembly and regulation.
Le Shen - One of the best experts on this subject based on the ideXlab platform.
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idiopathic pulmonary fibrosis is associated with Tight Junction protein alterations
Biochimica et Biophysica Acta, 2020Co-Authors: Ye Li, Jimian Yu, Li Dong, Aliya N Husain, Le Shen, Christopher R WeberAbstract:Abstract Idiopathic pulmonary fibrosis (IPF) is a chronic disease characterized by an abnormal healing response to injury of the alveolar epithelium. Tight Junctions provide a physical barrier at the apical intercellular space between epithelial cells and regulate paracellular flux. While Tight Junction alterations are known to contribute to barrier dysfunction in a number of disease states, the role of Tight Junction proteins in IPF is poorly defined. To determine a potential role for Tight Junction protein alterations in IPF, we performed immunohistochemical staining for Tight Junction proteins ZO-1, occludin, claudin-2, claudin-3, claudin-4, claudin-5, and claudin-18. Staining intensity and localization were compared between IPF and control lung tissues. IPF was associated with type II pneumocyte hyperplasia and altered Tight Junction protein expression. While there was no difference in the expression of ZO-1, claudin-3, or claudin-5, between IPF and normal control, there was an overall increase in claudin-2 expression in bronchiolar and alveolar epithelium and a decrease in claudin-4 expression in type II pneumocytes. There was also increased occludin and decreased claudin-18 expression in pneumocytes overlying fibroblastic foci. These findings suggest that epithelial barrier alterations may be important to the pathogenesis of IPF.
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Tight Junction pore and leak pathways a dynamic duo
Annual Review of Physiology, 2011Co-Authors: Le Shen, Christopher R Weber, David R Raleigh, Dan YuAbstract:Tissue barriers that restrict passage of liquids, ions, and larger solutes are essential for the development of multicellular organisms. In simple organisms this allows distinct cell types to interface with the external environment. In more complex species, the diversity of cell types capable of forming barriers increases dramatically. Although the plasma membranes of these barrier-forming cells prevent flux of most hydrophilic solutes, the paracellular, or shunt, pathway between cells must also be sealed. This function is accomplished in vertebrates by the zonula occludens, or Tight Junction. The Tight Junction barrier is not absolute but is selectively permeable and is able to discriminate between solutes on the basis of size and charge. Many Tight Junction components have been identified over the past 20 years, and recent progress has provided new insights into the proteins and interactions that regulate structure and function. This review presents these data in a historical context and proposes an int...
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epithelial myosin light chain kinase activation induces mucosal interleukin 13 expression to alter Tight Junction ion selectivity
Journal of Biological Chemistry, 2010Co-Authors: Christopher R Weber, Le Shen, David R Raleigh, Yingmin Wang, Liping Su, Erika A Sullivan, Jerrold R TurnerAbstract:Intestinal barrier function is reduced in inflammatory bowel disease (IBD). Tumor necrosis factor (TNF) and interleukin (IL)-13, which are up-regulated in IBD, induce barrier defects that are associated with myosin light chain kinase (MLCK) activation and increased claudin-2 expression, respectively, in cultured intestinal epithelial monolayers. Here we report that these independent signaling pathways have distinct effects on Tight Junction barrier properties and interact in vivo. MLCK activation alters size selectivity to enhance paracellular flux of uncharged macromolecules without affecting charge selectivity and can be rapidly reversed by MLCK inhibition. In contrast, IL-13-dependent claudin-2 expression increases paracellular cation flux in vitro and in vivo without altering Tight Junction size selectivity but is unaffected by MLCK inhibition in vitro. In vivo, MLCK activation increases paracellular flux of uncharged macromolecules and also triggers IL-13 expression, claudin-2 synthesis, and increased paracellular cation flux. We conclude that reversible, MLCK-dependent permeability increases cause mucosal immune activation that, in turn, feeds back on the Tight Junction to establish long-lasting barrier defects. Interactions between these otherwise distinct Tight Junction regulatory pathways may contribute to IBD pathogenesis.
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caveolin 1 dependent occludin endocytosis is required for tnf induced Tight Junction regulation in vivo
Journal of Cell Biology, 2010Co-Authors: Amanda M Marchiando, Christopher R Weber, Le Shen, David R Raleigh, Vallen W Graham, Brad T Schwarz, Jotham R Austin, Yanfang Guan, Alastair J M Watson, Marshall H MontroseAbstract:Epithelial paracellular barrier function, determined primarily by Tight Junction permeability, is frequently disrupted in disease. In the intestine, barrier loss can be mediated by tumor necrosis factor (α) (TNF) signaling and epithelial myosin light chain kinase (MLCK) activation. However, TNF induces only limited alteration of Tight Junction morphology, and the events that couple structural reorganization to barrier regulation have not been defined. We have used in vivo imaging and transgenic mice expressing fluorescent-tagged occludin and ZO-1 fusion proteins to link occludin endocytosis to TNF-induced Tight Junction regulation. This endocytosis requires caveolin-1 and is essential for structural and functional Tight Junction regulation. These data demonstrate that MLCK activation triggers caveolin-1–dependent endocytosis of occludin to effect structural and functional Tight Junction regulation.
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Tight Junction associated marvel proteins marveld3 tricellulin and occludin have distinct but overlapping functions
Molecular Biology of the Cell, 2010Co-Authors: David R Raleigh, Le Shen, Amanda M Marchiando, Yong Zhang, Hiroyuki Sasaki, Yingmin Wang, Manyuan Long, Jerrold R TurnerAbstract:In vitro studies have demonstrated that occludin and tricellulin are important for Tight Junction barrier function, but in vivo data suggest that loss of these proteins can be overcome. The presence of a heretofore unknown, yet related, protein could explain these observations. Here, we report marvelD3, a novel Tight Junction protein that, like occludin and tricellulin, contains a conserved four-transmembrane MARVEL (MAL and related proteins for vesicle trafficking and membrane link) domain. Phylogenetic tree reconstruction; analysis of RNA and protein tissue distribution; immunofluorescent and electron microscopic examination of subcellular localization; characterization of intracellular trafficking, protein interactions, dynamic behavior, and siRNA knockdown effects; and description of remodeling after in vivo immune activation show that marvelD3, occludin, and tricellulin have distinct but overlapping functions at the Tight Junction. Although marvelD3 is able to partially compensate for occludin or tricellulin loss, it cannot fully restore function. We conclude that marvelD3, occludin, and tricellulin define the Tight Junction–associated MARVEL protein family. The data further suggest that these proteins are best considered as a group with both redundant and unique contributions to epithelial function and Tight Junction regulation.
Alan S L Yu - One of the best experts on this subject based on the ideXlab platform.
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claudins and the modulation of Tight Junction permeability
Physical Review, 2013Co-Authors: Dorothee Gunzel, Alan S L YuAbstract:Claudins are Tight Junction membrane proteins that are expressed in epithelia and endothelia and form paracellular barriers and pores that determine Tight Junction permeability. This review summarizes our current knowledge of this large protein family and discusses recent advances in our understanding of their structure and physiological functions.
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renal localization and function of the Tight Junction protein claudin 19
American Journal of Physiology-renal Physiology, 2007Co-Authors: Susanne Angelow, Randa Elhusseini, Sanae A Kanzawa, Alan S L YuAbstract:Claudins form a family of transmembrane Tight Junction proteins that play a key role in control and selectivity of paracellular transport. Mutations in claudin-19, which is expressed in kidney, ret...
Mikio Furuse - One of the best experts on this subject based on the ideXlab platform.
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complex phenotype of mice lacking occludin a component of Tight Junction strands
Molecular Biology of the Cell, 2000Co-Authors: Mitinori Saitou, Michael Fromm, Jörg-dieter Schulzke, Mikio Furuse, Hiroyuki Sasaki, Hiroshi Takano, Tetsuo Noda, Shoichiro TsukitaAbstract:Occludin is an integral membrane protein with four transmembrane domains that is exclusively localized at Tight Junction (TJ) strands. Here, we describe the generation and analysis of mice carrying...
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occludin and claudins in Tight Junction strands leading or supporting players
Trends in Cell Biology, 1999Co-Authors: Shoichiro Tsukita, Mikio FuruseAbstract:Abstract Tight Junctions have attracted much interest from cell biologists, especially electron microscopists, since on freeze–fracture electron microscopy they appear as a well-developed network of continuous, anastomosing intramembranous strands (Tight-Junction strands). These strands might be directly involved in the ‘barrier' as well as ‘fence' functions in epithelial and endothelial cell sheets, but until recently little was known of their constituents. This review discusses current understanding of the molecular architecture of Tight-Junction strands, focusing on the recent discovery of two distinct types of Tight-Junction-specific integral membrane proteins, occludin and claudins.
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occludin as a possible determinant of Tight Junction permeability in endothelial cells
Journal of Cell Science, 1997Co-Authors: Tetsuaki Hirase, Shoichiro Tsukita, Mikio Furuse, Mitinori Saitou, James M Staddon, Yuhko Andoakatsuka, Masahiko Itoh, Kazushi Fujimoto, Lee L RubinAbstract:Endothelial cells provide a crucial interface between blood and tissue environments. Free diffusion of substances across endothelia is prevented by the endothelial Tight Junction, the permeability of which varies enormously depending on tissue. Endothelial cells of the blood-brain barrier possess Tight Junctions of severely limited permeability, whereas those of non-neural tissue are considerably leakier, but the molecular basis for this difference is not clear. Occludin is a major transmembrane protein localizing at the Tight Junction. In this study, we show, by immunocytochemistry, that occludin is present at high levels and is distributed continuously at cell-cell contacts in brain endothelial cells. In contrast, endothelial cells of non-neural tissue have a much lower expression of occludin, which is distributed in a discontinuous fashion at cell-cell contacts. The apparent differences in occludin expression levels were directly confirmed by immunoblotting. The differences in occludin protein were reflected at the message level, suggesting transcriptional regulation of expression. We also show that occludin expression is developmentally regulated, being low in rat brain endothelial cells at postnatal day 8 but clearly detectable at post-natal day 70. Our data indicate that regulation of occludin expression may be a crucial determinant of the Tight Junction permeability properties of endothelial cells in different tissues.
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occludin is a functional component of the Tight Junction
Journal of Cell Science, 1996Co-Authors: Karin M Mccarthy, Robert D Lynch, Shoichiro Tsukita, Mikio Furuse, Ilze B Skare, Michael C Stankewich, Rick A Rogers, Eveline E SchneebergerAbstract:Occludin9s role in mammalian Tight Junction activity was examined by ‘labeling’ the occludin pool with immunologically detectable chick occludin. This was accomplished by first transfecting MDCK cell with the Lac repressor gene. HygR clones were then transfected with chick occludin cDNA inserted into a Lac operator construct. The resulting HygR/NeoR clones were plated on porous inserts and allowed to form Tight Junctions. Once steady state transepithelial electrical resistance was achieved, isopropyl- beta-D-thiogalactoside was added to induce chick occludin expression. Confocal laser scanning microscopy of monolayers immunolabeled with Oc-2 monoclonal antibody revealed that chick occludin localized precisely to the preformed Tight Junctions. When sparse cultures were maintained in low Ca2+ medium, chick occludin and canine ZO-1 co-localized to punctate sites in the cytoplasm suggesting their association within the same vesicular structures. In low calcium medium both proteins also co-localized to contact sites between occasional cell pairs, where a prominent bar was formed at the plasma membrane. Chick occludin was detectable by western blot within two hours of adding isopropyl- beta-D-thiogalactoside to monolayers that had previously achieved steady state transepithelial electrical resistance; this coincided with focal immunofluorescence staining for chick occludin at the cell membrane of some cells. A gradual rise in transepithelial electrical resistance, above control steady state values, began five hours after addition of the inducing agent reaching new steady state values, which were 30–40% above baseline, 31 hours later. Upon removal of isopropyl- beta-D-thiogalactoside chick occludin expression declined slowly until it was no longer detected in western blots 72 hours later; transepithelial electrical resistance also returned to baseline values during this time. While densitometric analysis of western blots indicated that the presence of chick occludin had no detectable effect on E-cadherin or ZO-1 expression, the possibility cannot be excluded that ZO-1 might be a limiting factor in the expression of chick occludin at the cell surface. To test whether expression of chick occludin affected the process of Tight Junction assembly, monolayers in low Ca2+ medium were treated with isopropyl- beta-D-thiogalactoside for 24 or 48 hours, before Ca2+ was added to stimulate Tight Junction assembly. Chick occludin did not alter the rate at which transepithelial electrical resistance developed, however, steady state values were 30–40% above control monolayers not supplemented with the inducing agent. By freeze fracture analysis, the number of parallel Tight Junction strands shifted from a mode of three in controls to four strands in cells expressing chick occludin and the mean width of the Tight Junction network increased from 175 +/- 11 nm to 248 +/- 16 nm. Two days after plating confluent monolayers that were induced to express chick occludin, mannitol flux was reduced to a variable degree relative to control monolayers. With continued incubation with the inducing agent, mannitol flux increased on day 11 to 50%, and TER rose to 45% above controls. Both of these changes were reversible upon removal of isopropyl- beta-D-thiogalactoside. These data are consistent with the notion that occludin contributes to the electrical barrier function of the Tight Junction and possibly to the formation of aqueous pores within Tight Junction strands.
Shoichiro Tsukita - One of the best experts on this subject based on the ideXlab platform.
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complex phenotype of mice lacking occludin a component of Tight Junction strands
Molecular Biology of the Cell, 2000Co-Authors: Mitinori Saitou, Michael Fromm, Jörg-dieter Schulzke, Mikio Furuse, Hiroyuki Sasaki, Hiroshi Takano, Tetsuo Noda, Shoichiro TsukitaAbstract:Occludin is an integral membrane protein with four transmembrane domains that is exclusively localized at Tight Junction (TJ) strands. Here, we describe the generation and analysis of mice carrying...
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occludin and claudins in Tight Junction strands leading or supporting players
Trends in Cell Biology, 1999Co-Authors: Shoichiro Tsukita, Mikio FuruseAbstract:Abstract Tight Junctions have attracted much interest from cell biologists, especially electron microscopists, since on freeze–fracture electron microscopy they appear as a well-developed network of continuous, anastomosing intramembranous strands (Tight-Junction strands). These strands might be directly involved in the ‘barrier' as well as ‘fence' functions in epithelial and endothelial cell sheets, but until recently little was known of their constituents. This review discusses current understanding of the molecular architecture of Tight-Junction strands, focusing on the recent discovery of two distinct types of Tight-Junction-specific integral membrane proteins, occludin and claudins.
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occludin as a possible determinant of Tight Junction permeability in endothelial cells
Journal of Cell Science, 1997Co-Authors: Tetsuaki Hirase, Shoichiro Tsukita, Mikio Furuse, Mitinori Saitou, James M Staddon, Yuhko Andoakatsuka, Masahiko Itoh, Kazushi Fujimoto, Lee L RubinAbstract:Endothelial cells provide a crucial interface between blood and tissue environments. Free diffusion of substances across endothelia is prevented by the endothelial Tight Junction, the permeability of which varies enormously depending on tissue. Endothelial cells of the blood-brain barrier possess Tight Junctions of severely limited permeability, whereas those of non-neural tissue are considerably leakier, but the molecular basis for this difference is not clear. Occludin is a major transmembrane protein localizing at the Tight Junction. In this study, we show, by immunocytochemistry, that occludin is present at high levels and is distributed continuously at cell-cell contacts in brain endothelial cells. In contrast, endothelial cells of non-neural tissue have a much lower expression of occludin, which is distributed in a discontinuous fashion at cell-cell contacts. The apparent differences in occludin expression levels were directly confirmed by immunoblotting. The differences in occludin protein were reflected at the message level, suggesting transcriptional regulation of expression. We also show that occludin expression is developmentally regulated, being low in rat brain endothelial cells at postnatal day 8 but clearly detectable at post-natal day 70. Our data indicate that regulation of occludin expression may be a crucial determinant of the Tight Junction permeability properties of endothelial cells in different tissues.
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occludin is a functional component of the Tight Junction
Journal of Cell Science, 1996Co-Authors: Karin M Mccarthy, Robert D Lynch, Shoichiro Tsukita, Mikio Furuse, Ilze B Skare, Michael C Stankewich, Rick A Rogers, Eveline E SchneebergerAbstract:Occludin9s role in mammalian Tight Junction activity was examined by ‘labeling’ the occludin pool with immunologically detectable chick occludin. This was accomplished by first transfecting MDCK cell with the Lac repressor gene. HygR clones were then transfected with chick occludin cDNA inserted into a Lac operator construct. The resulting HygR/NeoR clones were plated on porous inserts and allowed to form Tight Junctions. Once steady state transepithelial electrical resistance was achieved, isopropyl- beta-D-thiogalactoside was added to induce chick occludin expression. Confocal laser scanning microscopy of monolayers immunolabeled with Oc-2 monoclonal antibody revealed that chick occludin localized precisely to the preformed Tight Junctions. When sparse cultures were maintained in low Ca2+ medium, chick occludin and canine ZO-1 co-localized to punctate sites in the cytoplasm suggesting their association within the same vesicular structures. In low calcium medium both proteins also co-localized to contact sites between occasional cell pairs, where a prominent bar was formed at the plasma membrane. Chick occludin was detectable by western blot within two hours of adding isopropyl- beta-D-thiogalactoside to monolayers that had previously achieved steady state transepithelial electrical resistance; this coincided with focal immunofluorescence staining for chick occludin at the cell membrane of some cells. A gradual rise in transepithelial electrical resistance, above control steady state values, began five hours after addition of the inducing agent reaching new steady state values, which were 30–40% above baseline, 31 hours later. Upon removal of isopropyl- beta-D-thiogalactoside chick occludin expression declined slowly until it was no longer detected in western blots 72 hours later; transepithelial electrical resistance also returned to baseline values during this time. While densitometric analysis of western blots indicated that the presence of chick occludin had no detectable effect on E-cadherin or ZO-1 expression, the possibility cannot be excluded that ZO-1 might be a limiting factor in the expression of chick occludin at the cell surface. To test whether expression of chick occludin affected the process of Tight Junction assembly, monolayers in low Ca2+ medium were treated with isopropyl- beta-D-thiogalactoside for 24 or 48 hours, before Ca2+ was added to stimulate Tight Junction assembly. Chick occludin did not alter the rate at which transepithelial electrical resistance developed, however, steady state values were 30–40% above control monolayers not supplemented with the inducing agent. By freeze fracture analysis, the number of parallel Tight Junction strands shifted from a mode of three in controls to four strands in cells expressing chick occludin and the mean width of the Tight Junction network increased from 175 +/- 11 nm to 248 +/- 16 nm. Two days after plating confluent monolayers that were induced to express chick occludin, mannitol flux was reduced to a variable degree relative to control monolayers. With continued incubation with the inducing agent, mannitol flux increased on day 11 to 50%, and TER rose to 45% above controls. Both of these changes were reversible upon removal of isopropyl- beta-D-thiogalactoside. These data are consistent with the notion that occludin contributes to the electrical barrier function of the Tight Junction and possibly to the formation of aqueous pores within Tight Junction strands.
