Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Tyrosine phosphorylation and dissociation of occludin-ZO-1 and E-cadherin-beta-catenin complexes from the cytoskeleton by oxidative stress.

ABSTRACT: The oxidative-stress-induced alteration in paracellular junctional complexes was analysed in Caco-2 cell monolayer. Oxidative stress induced a rapid increase in tyrosine phosphorylation of occludin, zonula occludens (ZO)-1, E-cadherin and beta-catenin. An oxidative-stress-induced decrease in transepithelial electrical resistance was associated with a redistribution of occludin-ZO-1 and E-cadherin-beta-catenin complexes from the intercellular junctions. Genistein, a tyrosine kinase inhibitor, prevented the oxidative-stress-induced decrease in resistance and redistribution of protein complexes. Occludin, ZO-1, E-cadherin and beta-catenin in the Triton-insoluble cytoskeletal fraction were reduced by oxidative stress, which was prevented by genistein. Oxidative stress also reduced the co-immunoprecipitation of ZO-1 with occludin, which was prevented by genistein. Co-immunoprecipitation of beta-catenin with E-cadherin was unaffected by oxidative stress or genistein. ZO-1, E-cadherin and beta-catenin in the plasma membrane or membrane-cytoskeleton were either slightly reduced or unaffected by oxidative stress or genistein. These results show that oxidative stress induces tyrosine phosphorylation and cellular redistribution of occludin-ZO-1 and E-cadherin-beta-catenin complexes by a tyrosine-kinase-dependent mechanism.

SUBMITTER: Rao RK

PROVIDER: S-EPMC1222996 | biostudies-other | 2002 Dec

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

CK2-dependent phosphorylation of occludin regulates the interaction with ZO-proteins and tight junction integrity.

Project description:BACKGROUND: Casein kinase 2 (CK2) is a ubiquitously expressed Ser/Thr kinase with multiple functions in the regulation of cell proliferation and transformation. In targeting adherens and tight junctions (TJs), CK2 modulates the strength and dynamics of epithelial cell-cell contacts. Occludin previously was identified as a substrate of CK2, however the functional consequences of CK2-dependent occludin phosphorylation on TJ function were unknown. RESULTS: Here, we present evidence that phosphorylation of a Thr400-XXX-Thr404-XXX-Ser408 motif in the C-terminal cytoplasmic tail of human occludin regulates assembly/disassembly and barrier properties of TJs. In contrast to wildtype and T400A/T404A/S408A-mutated occludin, a phospho-mimetic Occ-T400E/T404E/S408E construct was impaired in binding to ZO-2. Interestingly, pre-phosphorylation of a GST-Occ C-terminal domain fusion protein attenuated binding to ZO-2, whereas, binding to ZO-1 was not affected. Moreover, Occ-T400E/T404E/S408E showed delayed reassembly into TJs in Ca2+-switch experiments. Stable expression of Occ-T400E/T404E/S408E in MDCK C11 cells augments barrier properties in enhancing paracellular resistance in two-path impedance spectroscopy, whereas expression of wildtype and Occ-T400A/T404A/S408A did not affect transepithelial resistance. CONCLUSIONS: These results suggest an important role of CK2 in epithelial tight junction regulation. The occludin sequence motif at amino acids 400-408 apparently represents a hotspot for Ser/Thr-kinase phosphorylation and depending on the residue(s) which are phosphorylated it differentially modulates the functional properties of the TJ.

| S-EPMC3695765 | biostudies-literature

Involvement of Src family kinases in N-cadherin phosphorylation and beta-catenin dissociation during transendothelial migration of melanoma cells.

Project description:N-cadherin is recruited to the heterotypic contact during transendothelial migration of melanoma cells in a coculture system with tumor cells seeded on top of a monolayer of endothelial cells. However, beta-catenin dissociates from N-cadherin and redistributes to the nucleus of transmigrating melanoma cells to activate gene transcription. In this report, we demonstrate that Src becomes activated at the heterotypic contact between the transmigrating melanoma cell and neighboring endothelial cells. Src activation shows close temporal correlation with tyrosine phosphorylation of N-cadherin. Expression of a dominant-negative Src in melanoma cells blocks N-cadherin phosphorylation, beta-catenin dissociation, and nuclear translocation in transmigrating cells, consistent with the involvement of Src family kinases. In in vitro binding assays, Src-mediated phosphorylation of the N-cadherin cytoplasmic domain results in a significant reduction in beta-catenin binding. Although five phospho-tyrosine residues can be identified on the N-cadherin cytoplasmic domain by mass spectrometry, site-specific mutagenesis indicates that Tyr-860 is the critical amino acid involved in beta-catenin binding. Overexpression of N-cadherin carrying the Y860F mutation inhibits the transmigration of transfected cells across the endothelium. Together, the data suggest a novel role for tyrosine phosphorylation of N-cadherin by Src family kinases in the regulation of beta-catenin association during transendothelial migration of melanoma cells.

| S-EPMC1382315 | biostudies-other

A complex affair: Attraction and repulsion make occludin and ZO-1 function!

Project description:Tight junctions (TJs) are protein complexes comprised of claudins, which anchor them in the membrane and numerous cytosolic scaffolding proteins including MAGI, MUPP1, cingulin and members of the Zonula Occludens (ZO) family. Originally, their main function was thought to be as a paracellular barrier. More recently, however, additional roles in signal transduction, differentiation and proliferation have been reported. Dysregulation is associated with a wide range of disease states, including diabetic retinopathy, irritable bowel disease and some cancers. ZO proteins and occludin form a protein complex that appears to act as a master regulator of TJ assembly/disassembly. Recent studies have highlighted the structural character of the primary ZO-1:occludin interaction and identified regions on occludin that control association and disassociation of TJ in a phosphorylation-dependent manner. We hypothesize that regions within ZO-1 in the so-called U5 and U6 regions behave in a similar manner.

| S-EPMC3879131 | biostudies-literature

Vascular endothelial-cadherin tyrosine phosphorylation in angiogenic and quiescent adult tissues.

Project description:Vascular endothelial-cadherin (VE-cadherin) plays a key role in angiogenesis and in vascular permeability. The regulation of its biological activity may be a central mechanism in normal or pathological angiogenesis. VE-cadherin has been shown to be phosphorylated on tyrosine in vitro under various conditions, including stimulation by VEGF. In the present study, we addressed the question of the existence of a tyrosine phosphorylated form of VE-cadherin in vivo, in correlation with the quiescent versus angiogenic state of adult tissues. Phosphorylated VE-cadherin was detected in mouse lung, uterus, and ovary but not in other tissues unless mice were injected with peroxovanadate to block protein phosphatases. Remarkably, VE-cadherin tyrosine phosphorylation was dramatically increased in uterus and ovary, and not in other organs, during PMSG/hCG-induced angiogenesis. In parallel, we observed an increased association of VE-cadherin with Flk1 (VEGF receptor 2) during hormonal angiogenesis. Additionally, Src kinase was constitutively associated with VE-cadherin in both quiescent and angiogenic tissues and increased phosphorylation of VE-cadherin-associated Src was detected in uterus and ovary after hormonal treatment. Src-VE-cadherin association was detected in cultured endothelial cells, independent of VE-cadherin phosphorylation state and Src activation level. In this model, Src inhibition impaired VEGF-induced VE-cadherin phosphorylation, indicating that VE-cadherin phosphorylation was dependent on Src activation. We conclude that VE-cadherin is a substrate for tyrosine kinases in vivo and that its phosphorylation, together with that of associated Src, is increased by angiogenic stimulation. Physical association between Flk1, Src, and VE-cadherin may thus provide an efficient mechanism for amplification and perpetuation of VEGF-stimulated angiogenic processes.

| S-EPMC2798002 | biostudies-literature

Glycoprotein 90K Promotes E-Cadherin Degradation in a Cell Density-Dependent Manner via Dissociation of E-Cadherin-p120-Catenin Complex.

Project description:Glycoprotein 90K (also known as LGALS3BP or Mac-2BP) is a tumor-associated protein, and high 90K levels are associated with poor prognosis in some cancers. To clarify the role of 90K as an indicator for poor prognosis and metastasis in epithelial cancers, the present study investigated the effect of 90K on an adherens junctional protein, E-cadherin, which is frequently absent or downregulated in human epithelial cancers. Treatment of certain cancer cells with 90K significantly reduced E-cadherin levels in a cell-population-dependent manner, and these cells showed decreases in cell adhesion and increases in invasive cell motility. Mechanistically, 90K-induced E-cadherin downregulation occurred via ubiquitination-mediated proteasomal degradation. 90K interacted with the E-cadherin-p120-catenin complex and induced its dissociation, altering the phosphorylation status of p120-catenin, whereas it did not associate with ?-catenin. In subconfluent cells, 90K decreased membrane-localized p120-catenin and the membrane fraction of the p120-catenin. Particularly, 90K-induced E-cadherin downregulation was diminished in p120-catenin knocked-down cells. Taken together, 90K upregulation promotes the dissociation of the E-cadherin-p120-catenin complex, leading to E-cadherin proteasomal degradation, and thereby destabilizing adherens junctions in less confluent tumor cells. Our results provide a potential mechanism to explain the poor prognosis of cancer patients with high serum 90K levels.

| S-EPMC5751204 | biostudies-literature

Intestinal HT-29 cells with dysfunction of E-cadherin show increased pp60src activity and tyrosine phosphorylation of p120-catenin.

Project description:1. HT-29 M6 cells are a subpopulation of HT-29 cells that, contrarily to the parental cells, establish tight cell contacts and differentiate. Cell-to-cell contacts in HT-29 M6 cells are also regulated by protein kinase C; addition of the phorbol ester phorbol 12-myristate 13-acetate (PMA) decreases the homotypic contacts of these cells. We show here that HT-29 cells or HT-29 M6 cells treated with PMA contain lower levels of functional E-cadherin, determined by analysing the association of this protein with the cytoskeleton. No significant differences in the localization of alpha-, beta-, or p120-catenins were detected under the three different conditions. 2. Dysfunction of E-cadherin can be reversed by incubation of HT-29 cells with the tyrosine kinase inhibitor herbimycin A. On the other hand an augmentation of c-src activity in HT-29 cells or HT-29 M6 cells treated with PMA was observed with respect to control HT-29 M6 cells. The phosphorylation status of catenins was also investigated; in HT-29 or in HT-29 M6 cells treated with PMA, dysfunction of E-cadherin was accompanied by an increased phosphorylation of p120-catenin and by an elevated association of this protein to E-cadherin. These results suggest a role for pp60src and the pp60src substrate p120-catenin in the control of E-cadherin function in HT-29 cells.

| S-EPMC1217474 | biostudies-other

p120 catenin associates with kinesin and facilitates the transport of cadherin-catenin complexes to intercellular junctions.

Project description:p120 catenin (p120) is a component of adherens junctions and has been implicated in regulating cadherin-based cell adhesion as well as the activity of Rho small GTPases, but its exact roles in cell-cell adhesion are unclear. Using time-lapse imaging, we show that p120-GFP associates with vesicles and exhibits unidirectional movements along microtubules. Furthermore, p120 forms a complex with kinesin heavy chain through the p120 NH2-terminal head domain. Overexpression of p120, but not an NH2-terminal deletion mutant deficient in kinesin binding, recruits endogenous kinesin to N-cadherin. Disruption of the interaction between N-cadherin and p120, or the interaction between p120 and kinesin, leads to a delayed accumulation of N-cadherin at cell-cell contacts during calcium-initiated junction reassembly. Our analyses identify a novel role of p120 in promoting cell surface trafficking of cadherins via association and recruitment of kinesin.

| S-EPMC2173663 | biostudies-literature

E-cadherin and APC compete for the interaction with beta-catenin and the cytoskeleton.

Project description:beta-Catenin is involved in the formation of adherens junctions of mammalian epithelia. It interacts with the cell adhesion molecule E-cadherin and also with the tumor suppressor gene product APC, and the Drosophila homologue of beta-catenin, armadillo, mediates morphogenetic signals. We demonstrate here that E-cadherin and APC directly compete for binding to the internal, armadillo-like repeats of beta-catenin; the NH2-terminal domain of beta-catenin mediates the interaction of the alternative E-cadherin and APC complexes to the cytoskeleton by binding to alpha-catenin. Plakoglobin (gamma-catenin), which is structurally related to beta-catenin, mediates identical interactions. We thus show that the APC tumor suppressor gene product forms strikingly similar associations as found in cell junctions and suggest that beta-catenin and plakoglobin are central regulators of cell adhesion, cytoskeletal interaction, and tumor suppression.

| S-EPMC2120290 | biostudies-other

p120-Catenin regulates leukocyte transmigration through an effect on VE-cadherin phosphorylation.

Project description:Vascular endothelial-cadherin (VE-cad) is localized to adherens junctions at endothelial cell borders and forms a complex with alpha-, beta-, gamma-, and p120-catenins (p120). We previously showed that the VE-cad complex disassociates to form short-lived "gaps" during leukocyte transendothelial migration (TEM); however, whether these gaps are required for leukocyte TEM is not clear. Recently p120 has been shown to control VE-cad surface expression through endocytosis. We hypothesized that p120 regulates VE-cad surface expression, which would in turn have functional consequences for leukocyte transmigration. Here we show that endothelial cells transduced with an adenovirus expressing p120GFP fusion protein significantly increase VE-cad expression. Moreover, endothelial junctions with high p120GFP expression largely prevent VE-cad gap formation and neutrophil leukocyte TEM; if TEM occurs, the length of time required is prolonged. We find no evidence that VE-cad endocytosis plays a role in VE-cad gap formation and instead show that this process is regulated by changes in VE-cad phosphorylation. In fact, a nonphosphorylatable VE-cad mutant prevented TEM. In summary, our studies provide compelling evidence that VE-cad gap formation is required for leukocyte transmigration and identify p120 as a critical intracellular mediator of this process through its regulation of VE-cad expression at junctions.

| S-EPMC2556612 | biostudies-literature

ZO-3, a novel member of the MAGUK protein family found at the tight junction, interacts with ZO-1 and occludin.

Project description:A 130-kD protein that coimmunoprecipitates with the tight junction protein ZO-1 was bulk purified from Madin-Darby canine kidney (MDCK) cells and subjected to partial endopeptidase digestion and amino acid sequencing. A resulting 19-amino acid sequence provided the basis for screening canine cDNA libraries. Five overlapping clones contained a single open reading frame of 2,694 bp coding for a protein of 898 amino acids with a predicted molecular mass of 98,414 daltons. Sequence analysis showed that this protein contains three PSD-95/SAP90, discs-large, ZO-1 (PDZ) domains, a src homology (SH3) domain, and a region similar to guanylate kinase, making it homologous to ZO-1, ZO-2, the discs large tumor suppressor gene product of Drosophila, and other members of the MAGUK family of proteins. Like ZO-1 and ZO-2, the novel protein contains a COOH-terminal acidic domain and a basic region between the first and second PDZ domains. Unlike ZO-1 and ZO-2, this protein displays a proline-rich region between PDZ2 and PDZ3 and apparently contains no alternatively spliced domain. MDCK cells stably transfected with an epitope-tagged construct expressed the exogenous polypeptide at an apparent molecular mass of approximately 130 kD. Moreover, this protein colocalized with ZO-1 at tight junctions by immunofluorescence and immunoelectron microscopy. In vitro affinity analyses demonstrated that recombinant 130-kD protein directly interacts with ZO-1 and the cytoplasmic domain of occludin, but not with ZO-2. We propose that this protein be named ZO-3.

| S-EPMC2132714 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data