OBJECTIVE To evaluate the possible role of tight junction protein Occludin in nasal polyps. METHODS The expression of Claudin-1, Occludin and ZO-1 in nasal polyps (n = 20) and healthy uncinate mucosa (n = 15) were examined using immunohistochemical staining, real-time quantitative polymerase chain reaction (PCR) and Western blot analysis. The regulatory effects of proinflammatory cytokines (IFN-γ, IL-13, IL-17, TGF-β, TGF-α) on the expression of Occludin in cultured human nasal epithelial cells were investigated. RESULTS The immunohistochemical results showed that Claudin-1, Occludin and ZO-1 were detected both in the nasal polyp group and the control group. The expression sites were the cell membrane and cytoplasm of nasal mucosa epithelial cells. The mean optical density of Claudin-1, Occludin and ZO-1 were 0.187 ± 0.076,0.172 ± 0.109 and 0.098 ± 0.035 respectively in the nasal polyp group and were significantly lower than those in the control group (0.312 ± 0.101, 0.220 ± 0.069 and 0.233
Endothelium differentiates in response to tissue-specific signals; brain endothelium expresses tight junctions and transporters which are absent from other endothelia. The promoter of the tight junction protein occludin exhibited strong activity in a brain endothelial cell line, hCMEC/D3 but was inactive in lung endothelial cells. Expression of occludin in brain endothelium corresponded with binding of Sp3 to a minimal promoter segment close to the transcription-start site. However, in lung endothelium Sp-transcription factors did not bind to this site although they are present in the cell nucleus. In contrast, repression of occludin in lung endothelium was associated with the binding of YY1 to a remote site in the promoter region, which was functionally inactive in brain endothelium. The work identified a group of transcription factors including Sp3 and YY1, which differentially interact with the occludin promoter to induce expression of occludin in brain endothelium and repression in other ...
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Occludin is an integral membrane protein, encoded by the OCLN gene, that is located at tight junctions. Tight junctions act as a physical barrier to prevent solutes and water from passing freely through the paracellular space. Occludin is also known as BLCPMG. It is known to interact with several cytoplasmic proteins via its C terminus, while its extracellular loops are thought to be involved in the regulation of paracellular permeability and cell adhesion. When occludin is expressed in cells that lack tight junctions, it is able to induce cell adhesion. Mutations in the OCLN gene are associated with an autosomal recessive neurologic disorder known as band-like calcification with simplified gyration and polymicrogyria (BLC-PMG).. ...
Occludin is an integral membrane protein, encoded by the OCLN gene, that is located at tight junctions. Tight junctions act as a physical barrier to prevent solutes and water from passing freely through the paracellular space. Occludin is also known as BLCPMG. It is known to interact with several cytoplasmic proteins via its C terminus, while its extracellular loops are thought to be involved in the regulation of paracellular permeability and cell adhesion. When occludin is expressed in cells that lack tight junctions, it is able to induce cell adhesion. Mutations in the OCLN gene are associated with an autosomal recessive neurologic disorder known as band-like calcification with simplified gyration and polymicrogyria (BLC-PMG).. ...
Occludin is a protein that in humans is encoded by the OCLN gene. Occludin is a 65-kDa (522-amino acid polypeptide -human) integral plasma-membrane protein located at the tight junctions, described for the first time in 1993 by Shoichiro Tsukita. Together with the Claudin group of proteins, it is the main component of the tight junctions. The OCLN gene is located on the long (q) arm of chromosome 5 at position q13.1. The gene starts at base pair 69,492,292 and goes to base pair 69,558,104 and is 65,813 base pairs long. Occludins structure can be broken down into 9 domains. These domains are separated into two groups. 5 of the domains are located intracellularly and extracellularly. These 5 domains are separated by the 4 transmembrane domains of the protein. The nine domains are as follows: N-terminus domain (66 aa) transmembrane domain 1 (23 aa) extracellular loop 1 (46 aa) transmembrane domain 2 (25 aa) intracellular loop (10 aa) transmembrane domain 3 (25 aa) extracellular domain 2 (48 aa) ...
Tight junctions (TJs) are essential for establishing a selectively permeable barrier to diffusion through the paracellular space between neighboring cells. TJs are composed of at least three types of transmembrane protein -occludin, claudin and junctional adhesion molecules (JAMs)- and a cytoplasmic plaque consisting of many different proteins that form large complexes. These are proposed to be involved in junction assembly, barrier regulation, cell polarity, gene transcription, and other pathways ...
Tight junctions (TJs) are essential for establishing a selectively permeable barrier to diffusion through the paracellular space between neighboring cells. TJs are composed of at least three types of transmembrane protein -occludin, claudin and junctional adhesion molecules (JAMs)- and a cytoplasmic plaque consisting of many different proteins that form large complexes. These are proposed to be involved in junction assembly, barrier regulation, cell polarity, gene transcription, and other pathways ...
In the new study, the Rockefeller researchers and colleagues at The Scripps Research Institute tested whether introducing some of these previously identified human genes into mice would allow them to infect the animals with the hepatitis C virus. The researchers compared two groups of mice: one group expressed two genes, CD81 and occludin, while mice in the second group were normal. They found that expression of human CD81 and human occludin in the mouse liver rendered the animals susceptible to HCV infection. Ploss and his colleagues also developed a novel reporter system, which allowed them to sensitively detect HCV infection in living animals.. "We have established a precedent for applying mouse genetics to dissect viral entry and validate the role of scavenger receptor type B class 1, a molecule that is being considered as a novel antiviral drug target, for HCV uptake in a living animal," says Charles M. Rice, Maurice R. and Corinne P. Greenberg Professor and head of the Laboratory of ...
Principal Investigator:TSUKITA Shoichiro, Project Period (FY):1997 - 1998, Research Category:Grant-in-Aid for international Scientific Research, Section:Joint Research, Research Field:Pathological medical chemistry
Monoklonale und polyklonale Occludin Antikörper für viele Methoden. Ausgesuchte Qualitäts-Hersteller für Occludin Antikörper. Hier bestellen.
Background The mind endothelium is a key component of the blood brain barrier which is compromised following ischemia allowing infiltration of damaging immune cells and other inflammatory molecules into the brain. that IVIg prevented the down-regulation of tight junction proteins claudin 5 and occludin and the decline in anti-apoptotic proteins Bcl-2 and Bcl-XL caused by […]. ...
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Tight junctions between epithelial and endothelial cells form selective barriers and paracellular channels and regulate paracellular transport of solutes, immune cells, and drugs. More specifically, tight junctions consist of proteins that laterally interconnect neighboring cells of epithelia and endothelia. Certain proteins seal the tight junction, so that a nearly impermeable barrier develops, whereas others form channels that allow for permeation between the cells. Recent investigations have focused on tight junction proteins, belonging to the claudin family (claudins-1 to -27 in humans) and the newly defined group of TAMP (three proteins: occludin, Marvel-D2, and tricellulin). Barriers and Channels Formed by Tight Junction Proteins I showcases work in this area clustered around three major themes: the molecular properties of tight junctions, for example, the role of the claudin family of proteins and the formation of ion and charge-selective channels; the regulation of tight junction
In an attempt to clarify the complex nature of interactions between the cortical actin cytoskeleton and integral membrane proteins, recent studies brought into focus the ERM proteins, which serve as cross-linkers between specific plasma membrane proteins and cortical actin filaments. For ERM protein activation, specific signals, such as phosphorylation or binding of phosphatidylinositol 4,5-bisphosphate (lipid signaling molecule) to the N-terminal domain is required (8, 25, 36). Activation of ERM proteins may be triggered by physiological (14, 29) and pathophysiological (52, 58) processes. Ezrin is one of the host cytoskeletal proteins reorganized following EPEC infection (17). Here we examine the impact of this important enteric bacterial pathogen on ezrin activation and explore its involvement in EPEC pathogenesis.. In contrast to prototypic enteric bacterial pathogens, EPEC produces no recognized toxin and is essentially noninvasive. Instead, through a series of complex steps, EPEC intimately ...
The effect of Aβ on BBB integrity has been studied in several cell culture models. Gonzalez-Velasquez et al showed that treatment of cultured human brain endothelial cells with 2.5 to 10 μmol/L Aβ40 triggered the TJ protein ZO-1 to retreat from the plasma membrane, which was accompanied by decreased transendothelial electric resistance.11 Marco and Skaper demonstrated that exposing rat brain endothelial cells to 20 μmol/L Aβ42 triggered ZO-1 and claudin-5 relocation from the plasma membrane, a decrease in occludin expression, and an increase in claudin-1 expression.21 Tai et al demonstrated that Aβ40 activated microtubule-associated protein kinase, which decreased occludin expression and increased permeability in human brain endothelial cell cultures, whereas claudin-5 and ZO-1 remained unchanged.22 Carrano et al analyzed postmortem CAA patient brain slices for TJ protein and observed a loss of occludin, claudin-5, and ZO-1 in brain microvessels.23 We show that hAβ40 decreased rat brain ...
Epithelial layers are integral for many physiological processes and are maintained by intercellular adhesive structures. During disease, these structures can disassemble, leading to breakdown of epithelia. TJs (tight junctions) are one type of intercellular adhesion. Loss of TJs has been linked to the pathogenesis of many diseases. The present review focuses on the role of vesicle trafficking in regulation of TJs, in particular trafficking of the TJ protein occludin. We examine how endocytosis and endosomal recycling modulate occludin localization under steady-state conditions and during stimulated TJ disassembly. ...
This effect appeared to be mediated primarily by the action of HGF on the cytoplasmic membrane plaque protein ZO-1. ZO-1 is a peripheral membrane protein localized to the tight junction complex in epithelial and endothelial cells. Anchoring of ZO-1 with the underlying cytoskeleton is required for localization of occludin and claudin in the tight junction. ZO-1, -2, and -3 contain three PDZ domains, one SH3 domain, and one guanylyl kinase-like domain (GuK). Through its GuK domains, ZO-1 binds directly to the carboxyl termini of claudins and occludin and may function as an adaptor at the cytoplasmic surface of the tight junction to recruit other proteins, including cytoskeletal and signaling molecules. 4 These components can form a huge macromolecular complex at the cytoplasmic surface of tight junctions and may be involved in the regulation of endothelial and epithelial cell polarization, proliferation, and differentiation. 4 As an adaptor, ZO-1 is a critical regulatory protein between occludin ...
Characterization of the tight junction is proceeding rapidly and has stimulated advances in the fields of cell-cell interactions and epithelial cell biology. In addition to the list of proteins now found at the tight junction, we have learned that two previously characterized tight junction components, ZO-1 and ZO-2, are members of a larger protein family that appear to function in the organization of specific areas of the cell surface (11, 21, 23, 24, 27, 41, 44). Moreover, data suggest that some members of this family are involved in signal transduction and/or tumor suppression (1, 41, 46, 47), highlighting the importance of analyzing these molecules.. Here we present evidence of a novel member of the MAGUK family of proteins found at the tight junction. This 130-kD polypeptide, named ZO-3 because of homology to ZO-1 and ZO-2 (Figs. 5, Tables II and III) and localization at the tight junction (Figs. 7 and 8), contains 3 PDZ domains, an SH3 domain and a GUK region (Fig. 3). The arrangement of ...
VEGF signaling through PKCβ has been targeted for therapeutic intervention for retinal eye disease. Clinical evidence demonstrates that neutralizing antibodies to VEGF improves visual acuity in conjunction with laser photocoagulation for patients with diabetic macular edema (5). Previous publications have shown that PKCβ transduces a signal for VEGF-induced vascular permeability (6,32) and that a PKCβ-specific inhibitor, ruboxistaurin, partially blocks the progression of visual impairment (7-9,33). However, the downstream effectors from this kinase pathway and a mechanistic explanation for PKCβ regulation of permeability were unknown. Recent work from our laboratory has demonstrated that VEGF-induced occludin phosphorylation on Ser490 and subsequent ubiquitination changes the distribution of TJ proteins in retinal endothelial cells from cell border to intracellular puncta, promoting endothelial permeability (25). Here, we demonstrate that VEGF-induced activation of PKCβ results in ...
The effects of live yeast (LY) and mannan-oligosaccharide (MOS) supplementation on intestinal disruption induced by Escherichia coli in broilers were investigated. The experimental design was a 3×2 factorial arrangement with three dietary treatments (control, 0·5 g/kg LY (Saccharomyces cerevisiae, 1·0×1010 colony-forming units/g), 0·5 g/kg MOS) and two immune treatments (with or without E. coli challenge from 7 to 11 d of age). Samples were collected at 14 d of age. The results showed that E. coli challenge impaired (P,0·05) growth performance during the grower period (1-21 d) and the overall period (1-35 d) of broilers, increased (P,0·05) serum endotoxin and diamine oxidase levels coupled with ileal myeloperoxidase and lysozyme activities, whereas reduced (P,0·05) maltase activity, and compromised the morphological structure of the ileum. Besides, it increased (P,0·05) the mRNA expressions of several inflammatory genes and reduced occludin expression in the ileum. Dietary treatment ...
p38 MAPK is one of the major MAPK pathways activated by a variety of cellular stresses and cytokines, such as proinflammatory cytokines, growth factors, and reactive oxygen species.27 Induction of p38 MAPK activation by hypoxia and the effect of decorin in preventing this activation were detected in our study. We found that HG plus hypoxia-induced hyperpermeability, TER reduction, and tight junction protein (occludin and ZO-1) downregulation and disorganization can be prevented by inhibiting p38 MAPK activation. These findings suggested that decorin could reduce RPE barrier breakdown via inhibition of p38 MAPK activation. In addition, oxidative stress and inflammation are also the important factors for DR and DME. A number of articles have demonstrated that decorin core protein can inhibit inflammation by downregulating receptors such as TLRs, which are also associated with p38 MAPK pathway.22 However, little literature could prove the ability of decorin to regulate oxidative stress presently.49 ...
led, media is removed, and the cell layer is rinsed three times with cold PBS. The cells are scraped into 0.5 ml/dish of triton extraction buffer. The cell
The TJP2 protein (Tight Junction Protein 2, sometimes called ZO2) plays a role in "tight junctions". Tight junctions are areas where the membranes of two adjacent cells join to form a barrier. The barrier controls what molecules are able to pass between cells. Such junctions are important throughout the body, and TJP2 is not specific to the liver. A mild form of liver disease associated with mutations in the TPJ 2 gene was previously called familial hypercholanaemia (which means high bile salts in blood). Only a small number of patients with PFIC caused by TJP2 mutation have been studied so far, so it is not yet understood of what manifestations, other than liver disease and its consequences that TJP2 deficiency patients may have.. ...
In the present study, we demonstrate that HIV-infected leukocytes transmigrate in greater numbers across a tissue culture model of the human BBB in response to CCL2 than do uninfected cells, resulting in increased BBB permeability. This process was characterized by four major findings. First, BBB permeability was increased only when the combination of HIV-infected cells and a CCL2 chemotactic gradient was present. The addition of CCL2 alone or the adhesion of HIV-infected cells alone to the BBB model was not sufficient to induce BBB disruption. Second, the mechanism of BBB disruption and enhanced transmigration of HIV-infected cells was specifically CCL2 dependent, because other chemokines did not replicate the CCL2 effect. Third, the high HIV-infected leukocyte transmigration induced by CCL2 was associated with increased BBB permeability that correlated with a reduction in TJP (ZO-1, claudin-1, and occludin) and an increase in MMP-2 and MMP-9 in BBB cells. Fourth, HIV-infected leukocytes ...
Rabbit polyclonal antibody raised against synthetic peptide of MARVELD1. A synthetic peptide corresponding to N-terminus 16 amino acids of human MARVELD1. (PAB16868) - Products - Abnova
Instead, the Uppsala scientists, led by Professor Per Artursson, have focused on the other protein: the occludins, which are more static proteins. Experiments have been carried out on cells and have yet to be applied to living organisms. They synthesized peptides that correspond to different sequences in the loop that joins the canal between two cells. One of these peptides proved to increase the porosity of the intestinal wall when it was coupled with occludin molecules, but only from one side of the wall. From the other side, corresponding to the one from the intestine out into the body, the molecules proved to lump together or to be destroyed by enzymes before they had time to affect the filter. But the research team went one step further. By adding a fatty acid as a shield for the peptide part, they managed to increase the porosity from the other side as well. Whats more, the scientists succeeded in guiding the effect on the intestinal wall, from rapid and short to a longer lasting impact ...
The tight junction (TJ) is a dynamic structure that is controlled, in part, by the activity of the cytoskeleton. It has become abundantly clear that, in the presence of Ca2+, assembly of the TJ is the result of cellular interactions that trigger a complex cascade of biochemical events that ultimatel …
Obat ketika masuk tubuh mengalami nasib yaitu: absorbsi, distribusi, metabolisme, dan ekskresi (ADME). Obat utamanya masuk ke dalam sel. Sebenarnya aliran senyawa melalui paraseluler bisa terjadi, namun ada halangan yaitu adanya tight junction, misal di SSP. Obat bisa ditransport secara pasif maupun aktif. Transport pasif artinya mengikuti gradien konsentrasi yaitu dari konsentrasi tinggi ke konsentrasi…
The blood-testis barrier (BTB), one of the tightest blood-tissue barriers in the mammalian body, creates an immune-privileged site for postmeiotic spermatid development to avoid the production of antibodies against spermatid-specific antigens, many of which express transiently during spermiogenesis and spermiation. However, the BTB undergoes extensive restructuring at stage VIII of the epithelial cycle to facilitate the transit of preleptotene spermatocytes and to prepare for meiosis. This action thus prompted us to investigate whether this stage can be a physiological window for the delivery of therapeutic and/or contraceptive drugs across the BTB to exert their effects at the immune-privileged site. Herein, we report findings that P-glycoprotein, an ATP-dependent efflux drug transporter and an integrated component of the occludin/zonula occludens 1 (ZO-1) adhesion complex at the BTB, structurally interacted with focal adhesion kinase (FAK), creating the occludin/ZO-1/FAK/P-glycoprotein ...
In this study, we demonstrated (I) distinct expression patterns of five genes encoding for proteins involved in the formation of tight junctions in esophageal mucosa. In particular Claudin-1 in ERD and to lesser extent Claudin-2 was expressed at higher levels in patients with GERD. In contrast, ZO-1, ZO-2, and Occludin were not affected by the presence of GERD. (II) In general, altered gene expression of Claudin-1/-2 did not correlate with the degree of histomorphological changes in the esophageal mucosa of patients with GERD.. Tight junctions are composed of transmembrane proteins such as Occludin, 24 Claudins, several junctional adhesion molecules (JAMs) with different isoforms, E-Cadherin as well as cytosolic binding partners [43, 44]. The selection of the five genes studied was based on functional aspects. Occludin is critical for the formation of tight junctions in most tissues [45]. Claudin-1 is one of the numerous Claudins that seals intercellular space leading to higher barrier function ...
What happens to the paracellular barrier when the expression of tricellulin is suppressed in epithelial cells? Two independent Eph4 cell clones with suppressed tricellulin expression (KD-1 and KD-2) were established by stably expressing two distinct short interfering RNAs (Brummelkamp et al., 2002). In both clones, tricellulin protein expression was suppressed by ,95% as determined by Western blot analysis (Fig. 5 A), and immunofluorescence microscopy did not detect any tricellulin signals at tricellular contacts (Fig. 5 B). Under confluent conditions, KD-1 and KD-2 cells showed a typical cobblestone-like appearance, and there was no significant difference discerned between parental wild-type Eph4 and KD-1/2 cells with regard to the size/shape of individual cells and the distribution of cadherins (Fig. 5 B). However, when KD-1 and KD-2 cells were stained with anti-occludin mAb (Fig. 5 C) or anti-claudin-3 pAb (not depicted), tTJs as well as bTJs showed remarkable structural changes in that both ...
In mammalian epithelial cells, the most apical components of the lateral junctional complex are TJs that serve as intercellular barriers to regulate paracellular permeability and function as intramembranous fences to maintain the polarization of the apical and basolateral membrane domains ( Mitic and Anderson, 1998; Cereijido et al., 1998). A growing number of TJ-associated peripheral or integral proteins have been identified, and the characterized properties of these proteins provide a molecular basis for TJ formation and function. However, at present it is not fully understood how the formation of this complicated junctional structure is orchestrated in terms of the dynamic process.. We have previously identified ASIP, the mammalian homolog of C. elegans polarity protein PAR-3, as an epithelial TJ-associated peripheral protein ( Izumi et al., 1998); however, the physiological functions of mammalian ASIP/PAR-3 remain to be clarified. In this study, we provide two lines of evidence suggesting ...
Aim of this volume is to clarify the relationship between molecular structure and function of tight junction proteins, as well as their regulation and their role in diseases. Current research may form a basis for future diagnostic and therapeutic approaches to diseases which seem to have not much in common but are characterized by defects of organ barriers, like Crohns disease, renal hypertension, inner ear deafness, and cancerous diseases. Topics include the functions of distinct tight junction proteins as barrier or channel formers for solutes and water, characteristics of the tight junction in inflammatory bowel diseases, posttranslational modifications of tight junction proteins, the relation between renal tight junction proteins and blood pressure control, and the molecular structure of claudin-claudin interactions NOTE: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas.
Impairment of the BBB is a critical event in the development and progression of several diseases that affect the CNS. We demonstrated here that increased BBB permeability with downregulation of TJ and AJ proteins was involved in T2DM-induced cognitive impairment. TJs present between cerebral endothelial cells perform diffusion barrier functions of the BBB and consist of many proteins, such as claudin 3, claudin 5, occludin, and ZO-1. On the other hand, AJs are required for the correct organization of TJs and are largely composed of VE-cadherin in endothelial cells.1 Therefore, alteration of the interaction between these TJ proteins and VE-cadherin plays an essential role in modulating BBB function. Our results are consistent with these ideas and previous observations, suggesting that reduced ZO-1 and occludin expression, for example, might contribute to enhanced BBB permeability in diabetes mellitus.10 However, further alterations of BBB ultrastructure in diabetic patients or animal models are a ...
in Journal of Biological Chemistry (2011), 286(19), 16879-90. Extracellular Ca(2+) is essential for the development of stable epithelial tight junctions. We find that in the absence of extracellular Ca(2+), AMP-activated protein kinase (AMPK) activation and glycogen ... [more ▼]. Extracellular Ca(2+) is essential for the development of stable epithelial tight junctions. We find that in the absence of extracellular Ca(2+), AMP-activated protein kinase (AMPK) activation and glycogen synthase kinase (GSK)-3beta inhibition independently induce the localization of epithelial tight junction components to the plasma membrane. The Ca(2+)-independent deposition of junctional proteins induced by AMPK activation and GSK-3beta inhibition is independent of E-cadherin. Furthermore, the nectin-afadin system is required for the deposition of tight junction components induced by AMPK activation, but it is not required for that induced by GSK-3beta inhibition. Phosphorylation studies demonstrate that afadin is ...
Tight junctions consist of a branching network of sealing strands of protein. Each strand is assembled from a series of transmembrane proteins(JAMs/Junctional Adhesion Molecules,Claudins and Occludin) embedded in plasma membranes. The extracellular domains join each other in tight junctions,whereas the intracellular domains are linked to peripheral membrane proteins,linking the transmembrane protein strands to actin cytoskeleton to create a functional network that plays a role in cellular processes. Each strand functions as an individual or linear barrie, therefore, the number of transmembrane protein strands is in relation with the degree of paracellular electrical resistance and impedance to solute flux in tight junctions[1]. Although other types of proteins are present at tight junctions, however, occludin and claudin are the major ones contributing to the structure of tight junctions. ...
Tight junctions consist of a branching network of sealing strands of protein. Each strand is assembled from a series of transmembrane proteins(JAMs/Junctional Adhesion Molecules,Claudins and Occludin) embedded in plasma membranes. The extracellular domains join each other in tight junctions,whereas the intracellular domains are linked to peripheral membrane proteins,linking the transmembrane protein strands to actin cytoskeleton to create a functional network that plays a role in cellular processes. Each strand functions as an individual or linear barrie, therefore, the number of transmembrane protein strands is in relation with the degree of paracellular electrical resistance and impedance to solute flux in tight junctions[1]. Although other types of proteins are present at tight junctions, however, occludin and claudin are the major ones contributing to the structure of tight junctions. ...
In epithelia, specialized tricellular junctions (TCJs) mediate cell contacts at three-cell vertices. TCJs are fundamental to epithelial biology and disease, but only a few TCJ components are known, and how they assemble at tricellular vertices is not understood. Here we describe a transmembrane protein, Anakonda (Aka), which localizes to TCJs and is essential for the formation of tricellular, but not bicellular, junctions in Drosophila. Loss of Aka causes epithelial barrier defects associated with irregular TCJ structure and geometry, suggesting that Aka organizes cell corners. Aka is necessary and sufficient for accumulation of Gliotactin at TCJs, suggesting that Aka initiates TCJ assembly by recruiting other proteins to tricellular vertices. Akas extracellular domain has an unusual tripartite repeat structure that may mediate self-assembly, directed by the geometry of tricellular vertices. Conversely, Akas cytoplasmic tail is dispensable for TCJ localization. Thus, extracellular ...
The tight junction regulates passage of molecules throuth the paracellular spaces. Occludin and claudins are the specific trancmembrance protains present at the tight junction and are believed to regulate the cell barrier functions. To examine the response of the tight junction to hyperosmotic solutions, Ⅰinvestigated the effects of hyperosmotic glycerol on function and protein expression of the tight junction in ECV304 cells. Cell cytotoxicity analysis showed that the high (10%) concentration of glcerol damaged 64.1% of the ECV304 cells (p<0.001), and this was confirmed morphologically. Treatment with 1%, 2% or 5% glyserol increased the paracellular permeability of fluorescein isothiocyanate (FITC) -labeled dextran by 4.7%, 18.7% and 29.4% (p<0.05), respectively. In addition, exposure to glycerol at any concentration strongly reduced the expression of occludin, whereas enpression of claudin-1 was affected very slightly. These results suggest that hyperosmotic glycerol would certainly ...
Mouse monoclonal ZO1 tight junction protein antibody [mAbcam 61357] validated for WB, IP, Flow Cyt and tested in Human. Referenced in 2 publications and 5…
Inflammation caused by either intrinsic or extrinsic toxins results in intestinal barrier dysfunction, contributing to inflammatory bowel disease (IBD) and other diseases. Vitamin A is a widely used food supplement although its mechanistic effect on intestinal structures is largely unknown. The goal of this study was to explore the mechanism by investigating the influence of vitamin A on the intestinal barrier function, represented by tight junctions. IPEC-J2 cells were differentiated on transwell inserts and used as a model of intestinal barrier permeability. Transepithelial electrical resistance (TEER) was used as an indicator of monolayer integrity and paracellular permeability. Western blot and the reverse transcriptase-polymerase chain reaction were used to assess the protein and mRNA expression of tight junction proteins. Immunofluorescence microscopy was used to evaluate the localization and expression of tight junctions. Differentiated cells were treated with a vehicle control (Ctrl), ...
The precise regulation of intestinal epithelial TJs is crucial to maintaining barrier function between the luminal milieu and the internal environment. Recent studies have revealed an important role for Rho GTPases in regulating TJ structure/function (22, 29). In particular, TJ strand organization has been shown to be altered by constitutively active RhoA and Rac1 mutants (22) and inactivation of GTPases by C. difficile toxins is known to cause redistribution of occludin and ZO-1 from membrane microdomains or membrane rafts (32). As a result, we have further explored the mechanisms whereby paracellular permeability is influenced by this family of mediators and investigated whether the inactivation of a single GTPase (RhoA, Rac1, or Cdc42) has an effect on TJ distribution in such membrane rafts and whether TJ proteins involved in strand formation (such as claudin-1 and -2) are altered in this setting.. Using MDCK cell lines that express constitutively active or dominant-negative RhoA, Rac1, or ...
Two essential features of the RPE are its polarity and barrier properties. The RPE is polarized, because it separates the neural retina from the fenestrated capillaries in the choroid. The apical membrane of RPE interacts with the photoreceptors; the basal membrane interacts with the choroid. Like other epithelia, the apical and basolateral membranes have different protein compositions that enable each to interact with different environments. The barrier properties are regulated by two components. Transepithelial transport through the cells is regulated by plasma membrane pumps and transporters. Passive diffusion through the paracellular spaces is regulated by the strands of tight junctions that encircle each cell. Tight junctions are semi-selective, which means some solutes cross them more readily than others. By regulating both the transcellular and paracellular pathways, the RPE regulates the ionic composition of the subretinal space. For review see: Wilt SD, Rizzolo LJ: Unique aspects of the ...
Two essential features of the RPE are its polarity and barrier properties. The RPE is polarized, because it separates the neural retina from the fenestrated capillaries in the choroid. The apical membrane of RPE interacts with the photoreceptors; the basal membrane interacts with the choroid. Like other epithelia, the apical and basolateral membranes have different protein compositions that enable each to interact with different environments. The barrier properties are regulated by two components. Transepithelial transport through the cells is regulated by plasma membrane pumps and transporters. Passive diffusion through the paracellular spaces is regulated by the strands of tight junctions that encircle each cell. Tight junctions are semi-selective, which means some solutes cross them more readily than others. By regulating both the transcellular and paracellular pathways, the RPE regulates the ionic composition of the subretinal space. For review see: Wilt SD, Rizzolo LJ: Unique aspects of the ...
Complete information for MARVELD1 gene (Protein Coding), MARVEL Domain Containing 1, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene Compendium
Expression of OCLN (PPP1R115) in vagina tissue. Antibody staining with HPA005933, CAB013075, CAB068212, CAB068213 and CAB068214 in immunohistochemistry.
Restore optimal gut environment leads to great gut health with carbon rich alkaline liquid lignite extracts to strengthen tight junction cells
All of us in the business talk about the blood-brain barrier, but. . .no, Im not going to end this sentence with . . .none of us do anything about it,