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FASEB Journal : Official Publication of... Mar 2021Histamine-induced vascular leakage is a core process of allergic pathologies, including anaphylaxis. Here, we show that glycolysis is integral to histamine-induced...
Histamine-induced vascular leakage is a core process of allergic pathologies, including anaphylaxis. Here, we show that glycolysis is integral to histamine-induced endothelial barrier disruption and hyperpermeability. Histamine rapidly enhanced glycolysis in endothelial cells via a pathway that involved histamine receptor 1 and phospholipase C beta signaling. Consistently, partial inhibition of glycolysis with 3-(3-pyridinyl)-1-(4-pyridinyl)-2-propen-1-one (3PO) prevented histamine-induced hyperpermeability in human microvascular endothelial cells, by abolishing the histamine-induced actomyosin contraction, focal adherens junction formation, and endothelial barrier disruption. Pharmacologic blockade of glycolysis with 3PO in mice reduced histamine-induced vascular hyperpermeability, prevented vascular leakage in passive cutaneous anaphylaxis and protected from systemic anaphylaxis. In conclusion, we elucidated the role of glycolysis in histamine-induced disruption of endothelial barrier integrity. Our data thereby point to endothelial glycolysis as a novel therapeutic target for human pathologies related to excessive vascular leakage, such as systemic anaphylaxis.
Topics: Adherens Junctions; Anaphylaxis; Animals; Capillary Permeability; Endothelial Cells; Endothelium, Vascular; Glycolysis; Histamine; Mice; Phospholipase C beta; Signal Transduction
PubMed: 33566443
DOI: 10.1096/fj.202001634R -
Cell Reports Feb 2020We study punctate adherens junctions (pAJs) to determine how short-lived cadherin clusters and relatively stable actin bundles interact despite differences in dynamics....
We study punctate adherens junctions (pAJs) to determine how short-lived cadherin clusters and relatively stable actin bundles interact despite differences in dynamics. We show that pAJ-linked bundles consist of two distinct regions-the bundle stalk (AJ-BS) and a tip (AJ-BT) positioned between cadherin clusters and the stalk. The tip differs from the stalk in a number of ways: it is devoid of the actin-bundling protein calponin, and exhibits a much faster F-actin turnover rate. While F-actin in the stalk displays centripetal movement, the F-actin in the tip is immobile. The F-actin turnover in both the tip and stalk is dependent on cadherin cluster stability, which in turn is regulated by F-actin. The close bidirectional coupling between the stability of cadherin and associated F-actin shows how pAJs, and perhaps other AJs, allow cells to sense and coordinate the dynamics of the actin cytoskeleton in neighboring cells-a mechanism we term "dynasensing."
Topics: Actin Cytoskeleton; Actins; Adherens Junctions; Cadherins; Cell Line; Humans; Microfilament Proteins; Models, Biological; Subcellular Fractions
PubMed: 32101754
DOI: 10.1016/j.celrep.2020.01.106 -
Cells Feb 2022Transmembrane proteins of adherens and tight junctions are known targets for viruses and bacterial toxins. The coronavirus receptor ACE2 has been localized at the apical...
Transmembrane proteins of adherens and tight junctions are known targets for viruses and bacterial toxins. The coronavirus receptor ACE2 has been localized at the apical surface of epithelial cells, but it is not clear whether ACE2 is localized at apical Cell-Cell junctions and whether it associates with junctional proteins. Here we explored the expression and localization of ACE2 and its association with transmembrane and tight junction proteins in epithelial tissues and cultured cells by data mining, immunoblotting, immunofluorescence microscopy, and co-immunoprecipitation experiments. ACE2 mRNA is abundant in epithelial tissues, where its expression correlates with the expression of the tight junction proteins cingulin and occludin. In cultured epithelial cells ACE2 mRNA is upregulated upon differentiation and ACE2 protein is widely expressed and co-immunoprecipitates with the transmembrane proteins ADAM17 and CD9. We show by immunofluorescence microscopy that ACE2 colocalizes with ADAM17 and CD9 and the tight junction protein cingulin at apical junctions of intestinal (Caco-2), mammary (Eph4) and kidney (mCCD) epithelial cells. These observations identify ACE2, ADAM17 and CD9 as new epithelial junctional transmembrane proteins and suggest that the cytokine-enhanced endocytic internalization of junction-associated protein complexes comprising ACE2 may promote coronavirus entry.
Topics: ADAM17 Protein; Adherens Junctions; Angiotensin-Converting Enzyme 2; Cadherins; Carrier Proteins; Cell Line; Cell Membrane Permeability; Coronavirus; Epithelial Cells; Gene Expression; Intercellular Junctions; Tetraspanin 29; Tight Junction Proteins; Tight Junctions; Transcriptome
PubMed: 35203278
DOI: 10.3390/cells11040627 -
Annals of the New York Academy of... Oct 2022Epithelial cells are polarized with defined apical tight junctions (TJs), lateral adherens junctions (AJs), and basal integrin-matrix interactions. However, it is...
Epithelial cells are polarized with defined apical tight junctions (TJs), lateral adherens junctions (AJs), and basal integrin-matrix interactions. However, it is increasingly recognized that resident cell junction proteins can be found in varying locations and with previously unrecognized functions. Our study here presents the nanoarchitecture and nanocolocalization of cell junction proteins in culture and tissue by stochastic optical reconstruction microscopy (STORM). The Z-axial view of noncancerous MDCK-II and PZ-HPV-7 cell-cell junctions resolved β-catenin and p120 localizations to TJs and AJs, with p120 apical to β-catenin and colocalizing with TJ protein claudin-7. More basally, p120 and β-catenin become colocalized. This topography was lost in isogenic Ras-transformed MDCK cells and cancerous PC3 cells, where p120 becomes basally localized in relation to β-catenin. Claudin-7 gene conditional knockout (cKO) in mice also have altered polarity of p120 relative to β-catenin, like that seen in normal-to-cancer cell phenotypic transformation. Additionally, claudin-7 cKO resulted in redistribution and relocalization of other cell junction proteins, including claudin-1, zonula occludens-1, integrin α2, epithelial cell adhesion molecule, and focal adhesion kinase (FAK); specifically, integrin α2 and FAK were observed at the apical-lateral compartment. Our data show that STORM reveals regional cellular junction nanoarchitecture previously uncharacterized, providing new insight into potential trans-compartmental modulation of protein functions.
Topics: Adherens Junctions; Animals; Cadherins; Claudin-1; Claudins; Epithelial Cell Adhesion Molecule; Epithelial Cells; Focal Adhesion Protein-Tyrosine Kinases; Integrin alpha2; Mice; Microscopy; Tight Junctions; beta Catenin
PubMed: 35819053
DOI: 10.1111/nyas.14855 -
FEBS Letters Jan 2022The apical junctional complex (AJC) is a membrane protein ultrastructure that regulates cell adhesion and homeostasis. The tight junction (TJ) and the adherens junction...
The apical junctional complex (AJC) is a membrane protein ultrastructure that regulates cell adhesion and homeostasis. The tight junction (TJ) and the adherens junction (AJ) are substructures of the AJC. The interplay between TJ and AJ membrane proteins to assemble the AJC remains unclear. We employed synthetic biology strategies to express the basic membrane elements of a simple AJC-the adhesive extracellular domains of junctional adhesion molecule A (JAM-A), epithelial cadherin, claudin 1, and occludin-to study their interactions. Our results suggest that calcium concentration fluctuations and JAM-A, acting as an interface molecule between the TJ and AJ, orchestrate their interplay. Calcium affects the secondary structure, oligomerization, and binding affinity of homotypic and heterotypic interactions of TJ and AJ components, thus acting as a molecular switch influencing AJC dynamics.
Topics: Adherens Junctions
PubMed: 34882783
DOI: 10.1002/1873-3468.14252 -
Shock (Augusta, Ga.) Feb 2022ERG (ETS-related gene) is a member of the ETS (Erythroblast-transformation specific) family of transcription factors abundantly present in vascular endothelial cells....
ERG (ETS-related gene) is a member of the ETS (Erythroblast-transformation specific) family of transcription factors abundantly present in vascular endothelial cells. Recent studies demonstrate that ERG has important roles in blood vessel stability and angiogenesis. However, it is unclear how ERG is potentially involved in microvascular barrier functions and permeability. A wide variety of diseases and clinical conditions including trauma-hemorrhagic shock and burn injury are associated with microvascular dysfunctions, which causes excessive microvascular permeability, tissue edema and eventually, multiple organ dysfunction and death. The main purpose of this study was to determine the specific role of ERG in regulating microvascular permeability in human lung microvascular endothelial cells (HLMEC) and to evaluate if exogenous ERG will protect the barrier. The HLMECs were grown on Transwell inserts as monolayers and were transfected with ERG CRISPR/cas9 knockdown plasmid, ERG CRISPR activation plasmid, recombinant ERG protein or their respective controls. Recombinant vascular endothelial growth factor (VEGF) was used as an inducer of permeability for evaluating the effect of ERG activation on permeability. Changes in barrier integrity and permeability were studied using monolayer permeability assay and immunofluorescence of adherens junction proteins (VE-cadherin and β-catenin) respectively. CRISPR/cas9-based ERG knockdown as well as VEGF treatment induced monolayer hyperpermeability, VE-cadherin, and β-catenin junctional relocation and cytoskeletal F-actin stress fiber formation. CRISPR based ERG activation and recombinant ERG transfection attenuated VEGF-induced monolayer hyperpermeability. ERG activation preserved the adherens junctions and cytoskeleton. These results demonstrate that ERG is a potent regulator of barrier integrity and permeability in human lung microvascular endothelial cells and endogenously or exogenously enhancing ERG provides protection against barrier dysfunction and hyperpermeability.
Topics: Adherens Junctions; Capillary Permeability; Cells, Cultured; Endothelial Cells; Endothelium, Vascular; Humans; Microvessels; Transcriptional Activation; Transcriptional Regulator ERG
PubMed: 34907119
DOI: 10.1097/SHK.0000000000001899 -
Life (Basel, Switzerland) Nov 2022The Hippo pathway is an evolutionarily conserved pathway that serves to promote cell death and differentiation while inhibiting cellular proliferation across species.... (Review)
Review
The Hippo pathway is an evolutionarily conserved pathway that serves to promote cell death and differentiation while inhibiting cellular proliferation across species. The downstream effectors of this pathway, yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ), are considered vital in promoting the output of the Hippo pathway, with activation of upstream kinases negatively regulating YAP/TAZ activity. The upstream regulation of the Hippo pathway is not entirely understood on a molecular level. However, several studies have shown that numerous cellular and non-cellular mechanisms such as cell polarity, contact inhibition, soluble factors, mechanical forces, and metabolism can convey external stimuli to the intracellular kinase cascade, promoting the activation of key components of the Hippo pathway and therefore regulating the subcellular localisation and protein activity of YAP/TAZ. This review will summarise what we have learnt about the role of intercellular junction-associated proteins in the activation of this pathway, including adherens junctions and tight junctions, and in particular our latest findings about the desmosomal components, including desmoglein-3 (DSG3), in the regulation of YAP signalling, phosphorylation, and subcellular translocation.
PubMed: 36362947
DOI: 10.3390/life12111792 -
Nature Communications Apr 2020Rosettes are widely used in epithelial morphogenesis during embryonic development and organogenesis. However, their role in postnatal development and adult tissue...
Rosettes are widely used in epithelial morphogenesis during embryonic development and organogenesis. However, their role in postnatal development and adult tissue maintenance remains largely unknown. Here, we show zona glomerulosa cells in the adult adrenal cortex organize into rosettes through adherens junction-mediated constriction, and that rosette formation underlies the maturation of adrenal glomerular structure postnatally. Using genetic mouse models, we show loss of β-catenin results in disrupted adherens junctions, reduced rosette number, and dysmorphic glomeruli, whereas β-catenin stabilization leads to increased adherens junction abundance, more rosettes, and glomerular expansion. Furthermore, we uncover numerous known regulators of epithelial morphogenesis enriched in β-catenin-stabilized adrenals. Among these genes, we show Fgfr2 is required for adrenal rosette formation by regulating adherens junction abundance and aggregation. Together, our data provide an example of rosette-mediated postnatal tissue morphogenesis and a framework for studying the role of rosettes in adult zona glomerulosa tissue maintenance and function.
Topics: Adherens Junctions; Adrenal Gland Neoplasms; Animals; Animals, Newborn; Female; Humans; Male; Mice; Mice, Knockout; Microscopy, Electron, Transmission; Morphogenesis; Receptor, Fibroblast Growth Factor, Type 2; Zona Glomerulosa; beta Catenin
PubMed: 32245949
DOI: 10.1038/s41467-020-15332-7 -
Cellular and Molecular Life Sciences :... Jan 2022Blood vessels expand via sprouting angiogenesis, and this process involves numerous endothelial cell behaviors, such as collective migration, proliferation, cell-cell... (Review)
Review
Blood vessels expand via sprouting angiogenesis, and this process involves numerous endothelial cell behaviors, such as collective migration, proliferation, cell-cell junction rearrangements, and anastomosis and lumen formation. Subsequently, blood vessels remodel to form a hierarchical network that circulates blood and delivers oxygen and nutrients to tissue. During this time, endothelial cells become quiescent and form a barrier between blood and tissues that regulates transport of liquids and solutes. Bone morphogenetic protein (BMP) signaling regulates both proangiogenic and homeostatic endothelial cell behaviors as blood vessels form and mature. Almost 30 years ago, human pedigrees linked BMP signaling to diseases associated with blood vessel hemorrhage and shunts, and recent work greatly expanded our knowledge of the players and the effects of vascular BMP signaling. Despite these gains, there remain paradoxes and questions, especially with respect to how and where the different and opposing BMP signaling outputs are regulated. This review examines endothelial cell BMP signaling in vitro and in vivo and discusses the paradox of BMP signals that both destabilize and stabilize endothelial cell behaviors.
Topics: Animals; Blood Vessels; Bone Morphogenetic Proteins; Endothelial Cells; Humans; Intercellular Junctions; Neovascularization, Physiologic; Signal Transduction
PubMed: 35044529
DOI: 10.1007/s00018-021-04033-z -
Cells Feb 2024The integrity and permeability of epithelial and endothelial barriers depend on the formation of tight junctions, adherens junctions, and a junction-associated... (Review)
Review
The integrity and permeability of epithelial and endothelial barriers depend on the formation of tight junctions, adherens junctions, and a junction-associated cytoskeleton. The establishment of this junction-cytoskeletal module relies on the correct folding and oligomerization of its protein components. Molecular chaperones are known regulators of protein folding and complex formation in different cellular compartments. Mammalian cells possess an elaborate chaperone network consisting of several hundred chaperones and co-chaperones. Only a small part of this network has been linked, however, to the regulation of intercellular adhesions, and the systematic analysis of chaperone functions at epithelial and endothelial barriers is lacking. This review describes the functions and mechanisms of the chaperone-assisted regulation of intercellular junctions. The major focus of this review is on heat shock protein chaperones, their co-chaperones, and chaperonins since these molecules are the focus of the majority of the articles published on the chaperone-mediated control of tissue barriers. This review discusses the roles of chaperones in the regulation of the steady-state integrity of epithelial and vascular barriers as well as the disruption of these barriers by pathogenic factors and extracellular stressors. Since cytoskeletal coupling is essential for junctional integrity and remodeling, chaperone-assisted assembly of the actomyosin cytoskeleton is also discussed.
Topics: Animals; Cytoskeleton; Intercellular Junctions; Actin Cytoskeleton; Actomyosin; Molecular Chaperones; Mammals
PubMed: 38474334
DOI: 10.3390/cells13050370