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1

N-Cadherin-Mediated Human Granulosa Cell Adhesion Prevents Apoptosis  

PubMed Central

Studies suggest that cell-cell interactions may regulate apoptosis, and in particular, the calcium-dependent cell adhesion molecule N-cadherin has been shown to be capable of modulating this process. Rat granulosa cells (GCs) are known to express N-cadherin whereas cAMP is known to induce apoptosis in human and rat GCs. Based on these observations, we hypothesized that N-cadherin regulates human GC apoptosis via a cAMP-dependent mechanism. N-cadherin expression was evaluated in ovarian follicles and corpora lutea utilizing immunohistochemical techniques and in luteinized GCs in culture using immunoblotting, flow cytometric analysis, immunohistochemistry, and indirect immunofluorescence techniques utilizing anti-N-cadherin antibodies directed against both the extracellular and cytoplasmic domains of the molecule. Apoptosis was assessed by TUNEL and DNA fragmentation analysis and confirmed by flow cytometric cell cycle analysis and electron microscopy. The rate of GC apoptosis was found to be two- to three-fold lower among aggregated cells, as compared with single cells. N-cadherin was found to be expressed by aggregating GCs in vitro and GCs cultured in the presence of either N-cadherin function disrupting antibodies or peptides exhibiting enhanced rates of apoptosis. GCs in situ stained intensely for N-cadherin in preantral and normal growing preovulatory follicles as well as early corpora lutea. N-cadherin was weak in atretic follicles and regressing corpora lutea. Exposure of GCs to cAMP increased apoptosis while decreasing N-cadherin protein expression in a dose-dependent manner. Cell culture under serum-free conditions increased apoptosis and decreased N-cadherin expression, in part through cleavage of the extracellular domain of the molecule. The metalloproteinase inhibitor 1-10-phenanthroline inhibited the cleavage of the extracellular domain of N-cadherin and concomitantly inhibited the serum-deprivation-induced apoptosis of aggregated GCs. Collectively, these observations suggest that down-regulation of N-cadherin or the absence of a functional extracellular domain of the molecule prevents cell aggregation and is associated with GC apoptosis. In addition, cAMP induces apoptosis in a dose-dependent manner, and this process is dependent, at least in part, on regulation of the N-cadherin molecule at the surface of the cells. We conclude that N-cadherin-mediated GC signaling plays a central role in follicular and luteal cell survival.

Makrigiannakis, Antonis; Coukos, George; Christofidou-Solomidou, Melpo; Gour, Barbara J.; Radice, Glenn L.; Blaschuk, Orest; Coutifaris, Christos

1999-01-01

2

Neural cell-cell and cell-substrate adhesion through N-cadherin, N-CAM and L1.  

PubMed

In this study neural (N)-cadherin, neural cell adhesion molecule (N-CAM) and L1 proteins and their antibody equivalents were covalently immobilized on a polyethylene-imine (PEI)-coated glass surface to form neuron-adhesive coatings. Impedance sensing and (supplementary) image analysis were used to monitor the effects of these CAMs. Immobilization of high concentrations of both N-cadherin protein and antibody led to good adhesion of neurons to the modified surface, better than surfaces treated with 30.0 and 100.0 µg ml(-1) N-CAM protein and antibody. L1 antibody and protein coating revealed no significant effect on neuronal cell-substrate adhesion. In a second series of combinatorial experiments, we used the same antibodies and proteins as medium-additives to inhibit cell-cell adhesion between neurons. Adhesion of neurons cultured on N-cadherin protein or antibody-modified surfaces was lowered by the addition of a soluble N-cadherin protein and antibody to the culturing medium, accelerating neuronal aggregation. The presence of a soluble N-CAM antibody or protein had no effect on the adhesion of neuronal cells on a N-cadherin protein-modified surface. On a N-cadherin antibody-coated surface, the addition of a soluble N-CAM protein led to cell death of neurons after 48 h, while a N-CAM antibody had no effect. In the presence of a soluble N-cadherin protein and antibody the aggregation of neurons was inhibited, both on N-CAM protein and N-CAM antibody-modified surfaces. Neurons cultured on immobilized antibodies were less affected by the addition of soluble CAM blockers than neurons cultured on immobilized proteins, indicating that antibody-protein bonds are more stable compared to protein-protein bonds. PMID:21628769

Wiertz, R W F; Marani, E; Rutten, W L C

2011-05-31

3

Neural cell-cell and cell-substrate adhesion through N-cadherin, N-CAM and L1  

NASA Astrophysics Data System (ADS)

In this study neural (N)-cadherin, neural cell adhesion molecule (N-CAM) and L1 proteins and their antibody equivalents were covalently immobilized on a polyethylene-imine (PEI)-coated glass surface to form neuron-adhesive coatings. Impedance sensing and (supplementary) image analysis were used to monitor the effects of these CAMs. Immobilization of high concentrations of both N-cadherin protein and antibody led to good adhesion of neurons to the modified surface, better than surfaces treated with 30.0 and 100.0 µg ml-1 N-CAM protein and antibody. L1 antibody and protein coating revealed no significant effect on neuronal cell-substrate adhesion. In a second series of combinatorial experiments, we used the same antibodies and proteins as medium-additives to inhibit cell-cell adhesion between neurons. Adhesion of neurons cultured on N-cadherin protein or antibody-modified surfaces was lowered by the addition of a soluble N-cadherin protein and antibody to the culturing medium, accelerating neuronal aggregation. The presence of a soluble N-CAM antibody or protein had no effect on the adhesion of neuronal cells on a N-cadherin protein-modified surface. On a N-cadherin antibody-coated surface, the addition of a soluble N-CAM protein led to cell death of neurons after 48 h, while a N-CAM antibody had no effect. In the presence of a soluble N-cadherin protein and antibody the aggregation of neurons was inhibited, both on N-CAM protein and N-CAM antibody-modified surfaces. Neurons cultured on immobilized antibodies were less affected by the addition of soluble CAM blockers than neurons cultured on immobilized proteins, indicating that antibody-protein bonds are more stable compared to protein-protein bonds.

Wiertz, R. W. F.; Marani, E.; Rutten, W. L. C.

2011-08-01

4

Phosphorylation of N-Cadherin-associated Cortactin by Fer Kinase Regulates N-Cadherin Mobility and Intercellular Adhesion Strength  

Microsoft Academic Search

Cortactin regulates the strength of nascent N-cadherin-mediated intercellular adhesions through a tyrosine phosphory- lation-dependent mechanism. Currently, the functional significance of cortactin phosphorylation and the kinases respon- sible for the regulation of adhesion strength are not defined. We show that the nonreceptor tyrosine kinase Fer phosphorylates cadherin-associated cortactin and that this process is involved in mediating intercellular adhesion strength. In wild-type

Tarek Y. El Sayegh; Pamela D. Arora; Lingzhi Fan; Carol A. Laschinger; Peter A. Greer; Christopher A. McCulloch; Andras Kapus

2005-01-01

5

Chromosomal protein HMGN1 modulates the expression of N-cadherin  

PubMed Central

HMGN1 is a nuclear protein that binds to nucleosomes and alters the accessibility of regulatory factors to their chromatin targets. To elucidate its biological function and identify specific HMGN1 target genes, we generated Hmgn1?/? mice. DNA microarray analysis of Hmgn1+/+ and Hmgn1?/? embryonic fibroblasts identified N-cadherin as a potential HMGN1 gene target. RT-PCR and western blot analysis confirmed a linkage between HMGN1 expression and N-cadherin levels. In both transformed and primary mouse embryonic fibroblasts (MEFs), HMGN1 acted as negative regulator of N-cadherin expression. Likewise, the N-cadherin levels in early embryos of Hmgn1?/? mice were higher than those of their Hmgn1+/+ littermates. Loss of HMGN1 increased the adhesiveness, motility and aggregation potential of Hmgn1?/? MEFs, a phenotype consistent with increased levels of N-cadherin protein. Re-expression of wildtype HMGN1, but not of the mutant HMGN1 protein that does not bind to chromatin, in Hmgn1?/? MEFs, decreased the levels of N-cadherin and restored the Hmgn1+/+ phenotype. These studies demonstrate a role for HMGN1 in the regulation of specific gene expression. We suggest that in MEFs, and during early mouse development, the interaction of HMGN1 with chromatin down-regulates the expression of N-cadherin.

Rubinstein, Yaffa R.; Furusawa, Takashi; Lim, Jae-Hwan; Postnikov, Yuri V.; West, Katherine L.; Birger, Yehudit; Lee, Sunmin; Nguyen, Phuongmai; Trepel, Jane B.; Bustin, Michael

2013-01-01

6

Phosphorylation of N-Cadherin-associated Cortactin by Fer Kinase Regulates N-Cadherin Mobility and Intercellular Adhesion StrengthV?  

PubMed Central

Cortactin regulates the strength of nascent N-cadherin-mediated intercellular adhesions through a tyrosine phosphorylation-dependent mechanism. Currently, the functional significance of cortactin phosphorylation and the kinases responsible for the regulation of adhesion strength are not defined. We show that the nonreceptor tyrosine kinase Fer phosphorylates cadherin-associated cortactin and that this process is involved in mediating intercellular adhesion strength. In wild-type fibroblasts N-cadherin ligation-induced transient phosphorylation of Fer, indicating that junction formation activates Fer kinase. Tyrosine phosphorylation of cortactin after N-cadherin ligation was strongly reduced in fibroblasts expressing only catalytically inactive Fer (D743R), compared with wild-type cells. In wild-type cells, N-cadherin-coated bead pull-off assays induced fourfold greater endogenous N-cadherin association than in D743R cells. Fluorescence recovery after photobleaching showed that GFP-N-cadherin mobility at nascent contacts was 50% faster in wild-type than D743R cells. In shear wash-off assays, nascent intercellular adhesion strength was twofold higher in wild-type than D743R cells. Cortactin recruitment to adhesions was independent of Fer kinase activity, but was impacted by N-cadherin ligation-provoked Rac activation. We conclude that N-cadherin ligation induces Rac-dependent cortactin recruitment and Fer-dependent cortactin phosphorylation, which in turn promotes enhanced mobilization and interaction of surface expressed N-cadherin in contacting cells.

Sayegh, Tarek Y. El; Arora, Pamela D.; Fan, Lingzhi; Laschinger, Carol A.; Greer, Peter A.; McCulloch, Christopher A.; Kapus, Andras

2005-01-01

7

N-cadherin Regulates p38 MAPK Signaling via Association with JNK-associated Leucine Zipper Protein  

PubMed Central

Synaptic loss, which strongly correlates with the decline of cognitive function, is one of the pathological hallmarks of Alzheimer disease. N-cadherin is a cell adhesion molecule essential for synaptic contact and is involved in the intracellular signaling pathway at the synapse. Here we report that the functional disruption of N-cadherin-mediated cell contact activated p38 MAPK in murine primary neurons, followed by neuronal death. We further observed that treatment with A?42 decreased cellular N-cadherin expression through NMDA receptors accompanied by increased phosphorylation of both p38 MAPK and Tau in murine primary neurons. Moreover, expression levels of phosphorylated p38 MAPK were negatively correlated with that of N-cadherin in human brains. Proteomic analysis of human brains identified a novel interaction between N-cadherin and JNK-associated leucine zipper protein (JLP), a scaffolding protein involved in the p38 MAPK signaling pathway. We demonstrated that N-cadherin expression had an inhibitory effect on JLP-mediated p38 MAPK signal activation by decreasing the interaction between JLP and p38 MAPK in COS7 cells. Also, this study demonstrated a novel physical and functional association between N-cadherin and p38 MAPK and suggested neuroprotective roles of cadherin-based synaptic contact. The dissociation of N-cadherin-mediated synaptic contact by A? may underlie the pathological basis of neurodegeneration such as neuronal death, synaptic loss, and Tau phosphorylation in Alzheimer disease brain.

Ando, Koichi; Uemura, Kengo; Kuzuya, Akira; Maesako, Masato; Asada-Utsugi, Megumi; Kubota, Masakazu; Aoyagi, Nobuhisa; Yoshioka, Katsuji; Okawa, Katsuya; Inoue, Haruhisa; Kawamata, Jun; Shimohama, Shun; Arai, Tetsuaki; Takahashi, Ryosuke; Kinoshita, Ayae

2011-01-01

8

Structure-Function Analysis of Cell Adhesion by Neural (N-) Cadherin  

Microsoft Academic Search

To investigate the possible biological function of the lateral “strand dimer” observed in crystal structures of a D1 domain extracellular fragment from N-cadherin, we have undertaken site-directed mutagenesis studies of this molecule. Mutation of most residues important in the strand dimer interface abolish the ability of N-cadherin to mediate cell adhesion. Mutation of an analogous central residue (Trp-2) in E-cadherin

Kazuyoshi Tamura; Wei-Song Shan; Wayne A. Hendrickson; David R. Colman; Lawrence Shapiro

1998-01-01

9

Phosphatidylinositol-4,5 bisphosphate produced by PIP5KIgamma regulates gelsolin, actin assembly, and adhesion strength of N-cadherin junctions.  

PubMed

Phosphoinositides regulate several actin-binding proteins but their role at intercellular adhesions has not been defined. We found that phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) was generated at sites of N-cadherin-mediated intercellular adhesion and was a critical regulator of intercellular adhesion strength. Immunostaining for PI(4,5)P2 or transfection with GFP-PH-PLCdelta showed that PI(4,5)P2 was enriched at sites of N-cadherin adhesions and this enrichment required activated Rac1. Isoform-specific immunostaining for type I phosphatidylinositol 4-phosphate 5 kinase (PIP5KI) showed that PIP5KIgamma was spatially associated with N-cadherin-Fc beads. Association of PIP5KIgamma with N-cadherin adhesions was in part dependent on the activation of RhoA. Transfection with catalytically inactive PIP5KIgamma blocked the enrichment of PI(4,5)P2 around beads. Catalytically inactive PIP5KIgamma or a cell-permeant peptide that mimics and competes for the PI(4,5)P2-binding region of the actin-binding protein gelsolin inhibited incorporation of actin monomers in response to N-cadherin ligation and reduced intercellular adhesion strength by more than twofold. Gelsolin null fibroblasts transfected with a gelsolin severing mutant containing an intact PI(4,5)P2 binding region, demonstrated intercellular adhesion strength similar to wild-type transfected controls. We conclude that PIP5KIgamma-mediated generation of PI(4,5)P2 at sites of N-cadherin contacts regulates intercellular adhesion strength, an effect due in part to PI(4,5)P2-mediated regulation of gelsolin. PMID:17538019

El Sayegh, T Y; Arora, P D; Ling, K; Laschinger, C; Janmey, P A; Anderson, R A; McCulloch, C A

2007-05-30

10

Targeting Cx43 and N-Cadherin, Which Are Abnormally Upregulated in Venous Leg Ulcers, Influences Migration, Adhesion and Activation of Rho GTPases  

PubMed Central

Background Venous leg ulcers can be very hard to heal and represent a significant medical need with no effective therapeutic treatment currently available. Principal Findings In wound edge biopsies from human venous leg ulcers we found a striking upregulation of dermal N-cadherin, Zonula Occludens-1 and the gap junction protein Connexin43 (Cx43) compared to intact skin, and in stark contrast to the down-regulation of Cx43 expression seen in acute, healing wounds. We targeted the expression of these proteins in 3T3 fibroblasts to evaluate their role in venous leg ulcers healing. Knockdown of Cx43 and N-cadherin, but not Zonula Occludens-1, accelerated cell migration in a scratch wound-healing assay. Reducing Cx43 increased Golgi reorientation, whilst decreasing cell adhesion and proliferation. Furthermore, Connexin43 and N-cadherin knockdown led to profound effects on fibroblast cytoskeletal dynamics after scratch-wounding. The cells exhibited longer lamelipodial protrusions lacking the F-actin belt seen at the leading edge in wounded control cells. This phenotype was accompanied by augmented activation of Rac-1 and RhoA GTPases, as revealed by Förster Resonance Energy Transfer and pull down experiments. Conclusions Cx43 and N-cadherin are potential therapeutic targets in the promotion of healing of venous leg ulcers, by acting at least in part through distinct contributions of cell adhesion, migration, proliferation and cytoskeletal dynamics.

Mendoza-Naranjo, Ariadna; Cormie, Peter; Serrano, Antonio E.; Hu, Rebecca; O'Neill, Shay; Wang, Chiuhui Mary; Thrasivoulou, Christopher; Power, Kieran T.; White, Alexis; Serena, Thomas; Phillips, Anthony R. J.; Becker, David L.

2012-01-01

11

?-Catenin Localization and Sarcomere Self-Organization on N-Cadherin Adhesive Patterns Are Myocyte Contractility Driven  

PubMed Central

The N-cadherin (N-cad) complex plays a crucial role in cardiac cell structure and function. Cadherins are adhesion proteins linking adjacent cardiac cells and, like integrin adhesions, are sensitive to force transmission. Forces through these adhesions are capable of eliciting structural and functional changes in myocytes. Compared to integrins, the mechanisms of force transduction through cadherins are less explored. ?-catenin is a major component of the cadherin-catenin complex, thought to provide a link to the cell actin cytoskeleton. Using N-cad micropatterned substrates in an adhesion constrainment model, the results from this study show that ?-catenin localizes to regions of highest internal stress in myocytes. This localization suggests that ?-catenin acts as an adaptor protein associated with the cadherin mechanosensory apparatus, which is distinct from mechanosensing through integrins. Myosin inhibition in cells bound by integrins to fibronectin-coated patterns disrupts myofibiril organization, whereas on N-cad coated patterns, myosin inhibition leads to better organized myofibrils. This result indicates that the two adhesion systems provide independent mechanisms for regulating myocyte structural organization.

Shieh, Adrian C.; A. Janmey, Paul; Kresh, J. Yasha

2012-01-01

12

N-Cadherin signaling in synapse formation and neuronal physiology  

Microsoft Academic Search

Neural cadherin (N-cadherin) is an adhesion receptor that is localized in abundance at neuron-to-neuron synapses. N-cadherin\\u000a contains an extracellular domain that binds to other cadherins on juxtaposed cell membranes, a single-pass transmembrane region,\\u000a and a cytoplasmic tail that interacts with various proteins, including catenins, kinases, phosphatases, and presenilin 1.\\u000a N-cadherin contributes to the structural and functional organization of the synaptic

Juan L. Brusés

2006-01-01

13

N-cadherin-mediated cell adhesion restricts cell proliferation in the dorsal neural tube  

PubMed Central

Neural progenitors are organized as a pseudostratified epithelium held together by adherens junctions (AJs), multiprotein complexes composed of cadherins and ?- and ?-catenin. Catenins are known to control neural progenitor division; however, it is not known whether they function in this capacity as cadherin binding partners, as there is little evidence that cadherins themselves regulate neural proliferation. We show here that zebrafish N-cadherin (N-cad) restricts cell proliferation in the dorsal region of the neural tube by regulating cell-cycle length. We further reveal that N-cad couples cell-cycle exit and differentiation, as a fraction of neurons are mitotic in N-cad mutants. Enhanced proliferation in N-cad mutants is mediated by ligand-independent activation of Hedgehog (Hh) signaling, possibly caused by defective ciliogenesis. Furthermore, depletion of Hh signaling results in the loss of junctional markers. We therefore propose that N-cad restricts the response of dorsal neural progenitors to Hh and that Hh signaling limits the range of its own activity by promoting AJ assembly. Taken together, these observations emphasize a key role for N-cad–mediated adhesion in controlling neural progenitor proliferation. In addition, these findings are the first to demonstrate a requirement for cadherins in synchronizing cell-cycle exit and differentiation and a reciprocal interaction between AJs and Hh signaling.

Chalasani, Kavita; Brewster, Rachel M.

2011-01-01

14

Galectin-3 Protein Regulates Mobility of N-cadherin and GM1 Ganglioside at Cell-Cell Junctions of Mammary Carcinoma Cells*  

PubMed Central

Galectin-3 binding to cell surface glycoproteins, including branched N-glycans generated by N-acetylglucosaminyltransferase V (Mgat5) activity, forms a multivalent, heterogeneous, and dynamic lattice. This lattice has been shown to regulate integrin and receptor tyrosine kinase signaling promoting tumor cell migration. N-cadherin is a homotypic cell-cell adhesion receptor commonly overexpressed in tumor cells that contributes to cell motility. Here we show that galectin-3 and N-cadherin interact and colocalize with the lipid raft marker GM1 ganglioside in cell-cell junctions of mammary epithelial cancer cells. Disruption of the lattice by deletion of Mgat5, siRNA depletion of galectin-3, or competitive inhibition with lactose stabilizes cell-cell junctions. It also reduces, in a p120-catenin-dependent manner, the dynamic pool of junctional N-cadherin. Proteomic analysis of detergent-resistant membranes (DRMs) revealed that the galectin lattice opposes entry of many proteins into DRM rafts. N-cadherin and catenins are present in DRMs; however, their DRM distribution is not significantly affected by lattice disruption. Galectin lattice integrity increases the mobile fraction of the raft marker, GM1 ganglioside binding cholera toxin B subunit Ctb, at cell-cell contacts in a p120-catenin-independent manner, but does not affect the mobility of either Ctb-labeled GM1 or GFP-coupled N-cadherin in nonjunctional regions. Our results suggest that the galectin lattice independently enhances lateral molecular diffusion by direct interaction with specific glycoconjugates within the adherens junction. By promoting exchange between raft and non-raft microdomains as well as molecular dynamics within junction-specific raft microdomains, the lattice may enhance turnover of N-cadherin and other glycoconjugates that determine junctional stability and rates of cell migration.

Boscher, Cecile; Zheng, Yu Zi; Lakshminarayan, Ramya; Johannes, Ludger; Dennis, James W.; Foster, Leonard J.; Nabi, Ivan R.

2012-01-01

15

FAK and paxillin: regulators of N-cadherin adhesion and inhibitors of cell migration?  

Microsoft Academic Search

FAK and paxillin are important components in integrin- regulated signaling. New evidence suggests that these two proteins function in crosstalk between cell-matrix and cell-cell adhesions. Further, new insight suggests that under some conditions these proteins inhibit cell migration, in contrast to their established roles in several cell systems as positive regulators of cell adhesion and migration. FAK and paxillin are

Michael D. Schaller

2004-01-01

16

Asymmetric N-Cadherin Expression Results in Synapse Dysfunction, Synapse Elimination, and Axon Retraction in Cultured Mouse Neurons  

PubMed Central

Synapse elimination and pruning of axon collaterals are crucial developmental events in the refinement of neuronal circuits. While a control of synapse formation by adhesion molecules is well established, the involvement of adhesion molecules in developmental synapse loss is poorly characterized. To investigate the consequences of mis-match expression of a homophilic synaptic adhesion molecule, we analysed an asymmetric, exclusively postsynaptic expression of N-cadherin. This was induced by transfecting individual neurons in cultures of N-cadherin knockout mouse neurons with a N-cadherin expression vector. 2 days after transfection, patch-clamp analysis of AMPA receptor-mediated miniature postsynaptic currents revealed an impaired synaptic function without a reduction in the number of presynaptic vesicle clusters. Long-term asymmetric expression of N-cadherin for 8 days subsequently led to synapse elimination as indicated by a loss of colocalization of presynaptic vesicles and postsynaptic PSD95 protein. We further studied long-term asymmetric N-cadherin expression by conditional, Cre-induced knockout of N-cadherin in individual neurons in cultures of N-cadherin expressing cortical mouse neurons. This resulted in a strong retraction of axonal processes in individual neurons that lacked N-cadherin protein. Moreover, an in vivo asymmetric expression of N-cadherin in the developmentally transient cortico-tectal projection was indicated by in-situ hybridization with layer V neurons lacking N-cadherin expression. Thus, mis-match expression of N-cadherin might contribute to selective synaptic connectivity.

Pielarski, Kim N.; van Stegen, Bernd; Andreyeva, Aksana; Nieweg, Katja; Jungling, Kay; Redies, Christoph; Gottmann, Kurt

2013-01-01

17

Expression of motility-related protein MRP1/CD9, N-cadherin, E-cadherin, alpha-catenin and beta-catenin in retinoblastoma.  

PubMed

In our earlier study we showed that invasive retinoblastoma (RB) had down regulated tetraspanin protein KAI1/CD82, a family of cell surface glycoprotein. KAI1 may link to the cell surface molecules, such as integrins, E-cadherin, and other TM4SF members, and loss of KAI1 function may have a significant role in the progression of retinoblastoma. We also showed that epithelial cell adhesion molecule (EpCAM) is overexpressed in invasive RB. EpCAM expression decreases adhesion mediated by cadherins. Thus, we were further interested in studying the role of other adhesion molecules like cadherins and catenins in RB. We studied the expression of Motility-Related Protein 1 (MRP-1)/CD9, E-cadherin, N-cadherin, alpha-catenin and beta-catenin in RB and correlated clinicopathologically in 62 archival paraffin-embedded tumors by immunohistochemistry. There were 29 tumors with no invasion of choroids/optic nerve and 33 tumors with invasion of choroid/optic nerve/orbit. Western blotting was performed on 20 tumors using the same antibodies. We observed higher expression of CD9 (P<0.001), E-cadherin (P<0.001) and alpha-catenin (P<0.001) in the non-invasive RB and higher expression of N-cadherin (P<0.001) in invasive RB. The expression of beta-catenin was not significantly different between two groups of tumors. In Western blotting, we were able to see CD9 and E-cadherin expression in a minority of tumors while N-cadherin, alpha-catenin and beta-catenin were expressed with differing intensities in a majority of tumors. Thus, invasive tumors expressed increased N-cadherin, alpha-catenin and decreased E-cadherin and CD9. Thus, it appears that loss of E-cadherin and gain of N-cadherin expression are features of invasiveness. Further functional studies are required to evaluate the role of beta-catenin in RB. PMID:17316610

Mohan, Adithi; Nalini, Venkatesan; Mallikarjuna, Kandalam; Jyotirmay, Biswas; Krishnakumar, Subramanian

2007-01-09

18

Soluble N-cadherin fragment promotes angiogenesis  

Microsoft Academic Search

Endothelial cells express two dependent intercellular adhesion molecules: vascular endothelial (VE)-cadherin, specific for endothelial cells, and N-cadherin, also present in neuronal, lens, skeletal and heart muscle cells, osteoblasts, pericytes and fibroblasts. While there exists a vast amount of evidence that VE-cadherin promotes angiogenesis, the role of N-cadherin still remains to be elucidated. We found that a soluble 90-kDa fragment N-cadherin

L. Derycke; L. Morbidelli; M. Ziche; O. De Wever; M. Bracke; E. Van Aken

2006-01-01

19

Different pH-dependencies of the two synaptic adhesion molecules N-cadherin and cadherin-11 and the possible functional implication for long-term potentiation.  

PubMed

Ca(2+) -dependent adhesion molecules, cadherins, localised at synaptic sites are critically involved in long-term potentiation (LTP). N-cadherin is thought to promote LTP whereas cadherin-11 seems to counteract LTP. Since high synaptic activity is accompanied by local transient changes of the pH in the synaptic cleft, we studied whether the binding activity of cadherins is dependent on the pH and whether this might play a role during LTP. By atomic force microscopy (AFM) and laser tweezer experiments, we could show on the single molecule level as well as in a cell-based system that a decrease of the pH from 7.4 to 7.0 will result in a significant weakening of N-cadherin binding activity but in an increase of cadherin-11 binding. These differences in the pH dependencies of both molecules could be one explanation for their opposing roles during LTP. High-frequency stimulation will lead to a local acidosis in the synaptic cleft resulting in weakening of N-cadherin-mediated adhesion facilitating synaptic remodeling and LTP induction, whereas cadherin-11 bonds will be strengthened counteracting synaptic remodeling and LTP generation. Synapse 67:705-715, 2013. © 2013 Wiley Periodicals, Inc. PMID:23649972

Baumgartner, Werner; Osmanagic, Armin; Gebhard, Marita; Kraemer, Sandra; Golenhofen, Nikola

2013-06-03

20

N-cadherin mediates neuronal cell survival through Bim down-regulation.  

PubMed

N-cadherin is a major adhesion molecule involved in the development and plasticity of the nervous system. N-cadherin-mediated cell adhesion regulates neuroepithelial cell polarity, neuronal precursor migration, growth cone migration and synaptic plasticity. In vitro, it has been involved in signaling events regulating processes such as cell mobility, proliferation and differentiation. N-cadherin has also been implicated in adhesion-dependent protection against apoptosis in non-neuronal cells. In this study, we investigated if the engagement of N-cadherin participates to the control of neuronal cells survival/death balance. We observed that plating either primary mouse spinal cord neurons or primary rat hippocampal neurons on N-cadherin recombinant substrate greatly enhances their survival compared to non-specific adhesion on poly-L-lysine. We show that N-cadherin engagement, in the absence of other survival factors (cell-matrix interactions and serum), protects GT1-7 neuronal cells against apoptosis. Using this cell line, we then searched for the signaling pathways involved in the survival effect of N-cadherin engagement. The PI3-kinase/Akt survival pathway and its downstream effector Bad are not involved, as no phosphorylation of Akt or Bad proteins in response to N-cadherin engagement was observed. In contrast, N-cadherin engagement activated the Erk1/2 MAP kinase pathway. Moreover, N-cadherin ligation mediated a 2-fold decrease in the level of the pro-apoptotic protein Bim-EL whereas the level of the anti-apoptotic protein Bcl-2 was unchanged. Inhibition of Mek1/2 kinases with U0126, and the resulting inhibition of Erk1/2 phosphorylation, induced the increase of both the level of Bim-EL and apoptosis of cells seeded on the N-cadherin substrate, suggesting that Erk phosphorylation is necessary for cell survival. Finally, the overexpression of a phosphorylation defective form of Bim-EL prevented N-cadherin-engagement induced cell survival. In conclusion, our results show that N-cadherin engagement mediates neuronal cell survival by enhancing the MAP kinase pathway and down-regulating the pro-apoptotic protein Bim-EL. PMID:22427990

Lelièvre, Elise C; Plestant, Charlotte; Boscher, Cécile; Wolff, Emeline; Mège, René-Marc; Birbes, Hélène

2012-03-12

21

N-cadherin prodomain processing regulates synaptogenesis.  

PubMed

Classical cadherins, which are adhesion molecules functioning at the CNS synapse, are synthesized as adhesively inactive precursor proteins in the endoplasmic reticulum (ER). Signal sequence and prodomain cleavage in the ER and Golgi apparatus, respectively, activates their adhesive properties. Here, we provide the first evidence for sorting of nonadhesive precursor N-cadherin (ProN) to the neuronal surface, where it coexists with adhesively competent mature N-cadherin (N-cad), generating a spectrum of adhesive strengths. In cultured hippocampal neurons, a high ProN/N-cad ratio downregulates synapse formation. Neurons expressing genetically engineered uncleavable ProN make markedly fewer synapses. The synapse number can be rescued to normality by depleting surface ProN levels through prodomain cleavage by an exogenous protease. Finally, prodomain processing is developmentally regulated in the rat hippocampus. We conclude that it is the ProN/N-cad ratio and not mature N-cad alone that is critical for regulation of adhesion during synaptogenesis. PMID:22553038

Reinés, Analía; Bernier, Louis-Philippe; McAdam, Robyn; Belkaid, Wiam; Shan, Weisong; Koch, Alexander W; Séguéla, Philippe; Colman, David R; Dhaunchak, Ajit S

2012-05-01

22

Loss of the Retinoblastoma Tumor Suppressor Protein in Murine Calvaria Facilitates Immortalization of Osteoblast-Adipocyte Bipotent Progenitor Cells Characterized by Low Expression of N-Cadherin  

PubMed Central

The retinoblastoma gene, RB1, is frequently inactivated in a subset of tumors, including retinoblastoma and osteosarcoma (OS). One characteristic of OS, as well as other tumors in which RB1 is frequently inactivated, is the lack of N-cadherin-mediated cell-cell adhesions. The frequent inactivation of RB1 and parallel loss of N-cadherin expression in OS prompted us to ask whether these observations are directly related to each other. In this study, we observed reduced N-cadherin expression in RB1?/? calvarial osteoblasts. In addition, RB1?/? cell lines had increased migration potential compared to their RB1+/+ counterparts. These properties of RB1?/? cell lines correlated with an adipogenic potential lacking in RB1+/+ cell lines, suggesting that each property is present in an immature progenitor cell. The isolation of a cell population with low surface expression of N-cadherin and enhanced adipogenic ability supports this view. Interestingly, the acute loss of pRb does not affect N-cadherin expression or migration or confer adipogenic potential to immortalized RB1+/+ calvarial cells, suggesting that these traits are not a direct consequence of pRb loss; rather, pRb loss leads to the expansion and immortalization of an immature progenitor pool characterized by these properties.

Gunduz, Volkan; Kong, Elizabeth; Bryan, Crystal D.

2012-01-01

23

N-Cadherin Expression in Human Prostate Carcinoma Cell Lines An Epithelial-Mesenchymal Transformation Mediating Adhesion with Stromal Cells  

Microsoft Academic Search

In human prostate adenocarcinoma, an association between loss of E-cadherin, increased Gleason score, and extracapsular dissemination has been observed. Further characterization of the E-cadherin\\/catenin phenotype of human prostate carcinoma cell lines showed loss of E-cadherin and expression of N-cad- herin in poorly differentiated prostate carcinoma cell lines (PC-3N derived from PC-3, PC-3, and JCA1). We showed that N-cadherin is concentrated

Nhan L. Tran; Raymond B. Nagle; Anne E. Cress; Ronald L. Heimark

24

IQ-domain GTPase-activating protein 1 regulates beta-catenin at membrane ruffles and its role in macropinocytosis of N-cadherin and adenomatous polyposis coli.  

PubMed

Beta-catenin is an integral component of E-cadherin dependent cell-cell junctions. Here we show that beta-catenin co-localizes with IQ-domain GTPase-activating protein 1 (IQGAP1), adenomatous polyposis coli (APC), and N-cadherin at actin-positive membrane ruffles in NIH 3T3 fibroblasts. We used deletion mapping to identify the membrane ruffle-targeting region of beta-catenin, localizing it to amino acids 47-217, which overlap the IQGAP1 binding site. Knockdown by small interference RNA (siRNA) revealed IQGAP1-dependent membrane targeting of beta-catenin, APC, and N-cadherin. Transient overexpression of IQGAP1 or N-cadherin increased beta-catenin at membrane ruffles. IQGAP1/APC regulates cell migration, and using a wound healing assay we demonstrate that siRNA-mediated loss of beta-catenin also caused a modest reduction in the rate of cell migration. More significantly, we discovered that beta-catenin is internalized by Arf6-dependent macropinocytosis near sites of membrane ruffling. The beta-catenin macropinosomes co-stained for APC, N-cadherin, and to a lesser extent IQGAP1, and internalization of each binding partner was abrogated by siRNA-dependent knockdown of beta-catenin. In addition, beta-catenin macropinosomes co-localized with the lysosomal marker, lysosome associated membrane protein 1, consistent with their recycling by the late endosomal machinery. Our findings expand on current knowledge of beta-catenin function. We propose that in motile cells beta-catenin is recruited by IQGAP1 and N-cadherin to active membrane ruffles, wherein beta-catenin mediates the internalization and possible recycling of the membrane-associated proteins N-cadherin and APC. PMID:17255093

Sharma, Manisha; Henderson, Beric R

2007-01-24

25

N-CADHERIN REGULATES CYTOSKELETALLY-ASSOCIATED IQGAP1/ERK SIGNALING AND MEMORY FORMATION  

PubMed Central

Summary Cadherin-mediated interactions are integral to synapse formation and potentiation. Here we show that N-cadherin is required for memory formation and regulation of a subset of underlying biochemical processes. N-cadherin antagonistic peptide containing the His-Ala-Val motif (HAV-N) transiently disrupted hippocampal N-cadherin dimerization and impaired the formation of long-term contextual fear memory while sparing short-term memory, retrieval and extinction. HAV-N impaired the learning-induced phosphorylation of a distinctive, cytoskeletally-associated fraction of hippocampal Erk-1/2 and altered the distribution of IQGAP1, a scaffold protein linking cadherin-mediated cell adhesion to the cytoskeleton. This effect was accompanied by diminished of N-cadherin/IQGAP1/Erk-2 interactions. Similarly, in primary neuronal cultures, HAV-N prevented NMDA-induced dendritic Erk-1/2 phosphorylation and caused relocation of IQGAP1 from dendritic spines into the shafts. The data suggest that the newly identified role of hippocampal N-cadherin in memory consolidation may be mediated, at least in part, by cytoskeletal IQGAP1/Erk signaling.

Schrick, Christina; Fischer, Andre; Srivastava, Deepak P.; Tronson, Natalie C.; Penzes, Peter; Radulovic, Jelena

2007-01-01

26

N-cadherin is dispensable for pancreas development but required for ?-cell granule turnover  

PubMed Central

Summary The cadherin family of cell adhesion molecules mediates adhesive interactions that are required for the formation and maintenance of tissues. Previously, we demonstrated that N-cadherin, which is required for numerous morphogenetic processes, is expressed in the pancreatic epithelium at E9.5, but later becomes restricted to endocrine aggregates in mice. To study the role of N-cadherin during pancreas formation and function we generated a tissue specific knockout of N-cadherin in the early pancreatic epithelium by inter-crossing N-cadherin-floxed mice with Pdx1Cre mice. Analysis of pancreas-specific ablation of N-cadherin demonstrates that N-cadherin is dispensable for pancreatic development, but required for ?-cell granule turnover. The number of insulin secretory granules is significantly reduced in N-cadherin-deficient ?-cells, and as a consequence insulin secretion is decreased.

Johansson, Jenny K; Voss, Ulrikke; Kesavan, Gokul; Kostetskii, Igor; Wierup, Nils; Radice, Glenn L.; Semb, Henrik

2010-01-01

27

N-cadherin is dispensable for pancreas development but required for beta-cell granule turnover.  

PubMed

The cadherin family of cell adhesion molecules mediates adhesive interactions that are required for the formation and maintenance of tissues. Previously, we demonstrated that N-cadherin, which is required for numerous morphogenetic processes, is expressed in the pancreatic epithelium at E9.5, but later becomes restricted to endocrine aggregates in mice. To study the role of N-cadherin during pancreas formation and function we generated a tissue-specific knockout of N-cadherin in the early pancreatic epithelium by inter-crossing N-cadherin-floxed mice with Pdx1Cre mice. Analysis of pancreas-specific ablation of N-cadherin demonstrates that N-cadherin is dispensable for pancreatic development, but required for beta-cell granule turnover. The number of insulin secretory granules is significantly reduced in N-cadherin-deficient beta-cells, and as a consequence insulin secretion is decreased. PMID:20533404

Johansson, Jenny K; Voss, Ulrikke; Kesavan, Gokul; Kostetskii, Igor; Wierup, Nils; Radice, Glenn L; Semb, Henrik

2010-06-01

28

Dorsal Pancreas Agenesis in N-Cadherin- Deficient Mice  

Microsoft Academic Search

Members of the cadherin family of cell adhesion molecules are thought to be crucial regulators of tissue patterning and organogenesis. During pancreatic ontogeny N-cadherin is initially expressed in the pancreatic mesenchyme and later in pancreatic endoderm. Analysis of N-cadherin-deficient mice revealed that these mice suffer from selective agenesis of the dorsal pancreas. Further analysis demonstrated that the mechanism for the

Farzad Esni; Bengt R. Johansson; Glenn L. Radice; Henrik Semb

2001-01-01

29

N-cadherin induces partial differentiation of cholinergic presynaptic terminals in heterologous cultures of brainstem neurons and CHO cells  

PubMed Central

N-cadherin is a calcium-sensitive cell adhesion molecule commonly expressed at synaptic junctions and contributes to formation and maturation of synaptic contacts. This study used heterologous cell cultures of brainstem cholinergic neurons and transfected Chinese Hamster Ovary (CHO) cells to examine whether N-cadherin is sufficient to induce differentiation of cholinergic presynaptic terminals. Brainstem nuclei isolated from transgenic mice expressing enhanced green fluorescent protein (EGFP) under the control of choline acetyltransferase (ChAT) transcriptional regulatory elements (ChATBACEGFP) were cultured as tissue explants for 5 days and cocultured with transfected CHO cells for an additional 2 days. Immunostaining for synaptic vesicle proteins SV2 and synapsin I revealed a ~3-fold increase in the area of SV2 immunolabeling over N-cadherin expressing CHO cells, and this effect was enhanced by coexpression of p120-catenin. Synapsin I immunolabeling per axon length was also increased on N-cadherin expressing CHO cells but required coexpression of p120-catenin. To determine whether N-cadherin induces formation of neurotransmitter release sites, whole-cell voltage-clamp recordings of CHO cells expressing ?3 and ?4 nicotinic acetylcholine receptor (nAChR) subunits in contact with cholinergic axons were used to monitor excitatory postsynaptic potentials (EPSPs) and miniature EPSPs (mEPSPs). EPSPs and mEPSPs were not detected in both, control and in N-cadherin expressing CHO cells in the absence or presence of tetrodotoxin (TTX). These results indicate that expression of N-cadherin in non-neuronal cells is sufficient to initiate differentiation of presynaptic cholinergic terminals by inducing accumulation of synaptic vesicles; however, development of readily detectable mature cholinergic release sites and/or clustering of postsynaptic nAChR may require expression of additional synaptogenic proteins.

Flannery, Richard J.; Bruses, Juan L.

2012-01-01

30

Molecular Modification of N-Cadherin in Response to Synaptic Activity  

Microsoft Academic Search

The relationship between adhesive interactions across the synaptic cleft and synaptic function has remained elusive. At certain CNS synapses, pre- to postsynaptic adhesion is mediated at least in part by neural (N-) cadherin. Here, we demonstrate that upon depolarization of hippocampal neurons in culture by K+ treatment, or application of NMDA or ?-latrotoxin, synaptic N-cadherin dimerizes and becomes markedly protease

Hidekazu Tanaka; Weisong Shan; Greg R. Phillips; Kirsten Arndt; Ozlem Bozdagi; Lawrence Shapiro; George W. Huntley; Deanna L. Benson; David R. Colman

2000-01-01

31

N-cadherin haploinsufficiency affects cardiac gap junctions and arrhythmic susceptibility  

Microsoft Academic Search

Cardiac-specific deletion of the murine gene (Cdh2) encoding the cell adhesion molecule, N-cadherin, results in disassembly of the intercalated disc (ICD) structure and sudden arrhythmic death. Connexin 43 (Cx43)-containing gap junctions are significantly reduced in the heart after depleting N-cadherin, therefore we hypothesized that animals expressing half the normal levels of N-cadherin would exhibit an intermediate phenotype. We examined the

Jifen Li; Mark D. Levin; Yanming Xiong; Nataliya Petrenko; Vickas V. Patel; Glenn L. Radice

2008-01-01

32

Cell Surface Localization of ?3?4 Nicotinic Acetylcholine Receptors Is Regulated by N-Cadherin Homotypic Binding and Actomyosin Contractility  

PubMed Central

Neuronal nicotinic acetylcholine receptors (nAChRs) are widely expressed throughout the central and peripheral nervous system and are localized at synaptic and extrasynaptic sites of the cell membrane. However, the mechanisms regulating the localization of nicotinic receptors in distinct domains of the cell membrane are not well understood. N-cadherin is a cell adhesion molecule that mediates homotypic binding between apposed cell membranes and regulates the actin cytoskeleton through protein interactions with the cytoplasmic domain. At synaptic contacts, N-cadherin is commonly localized adjacent to the active zone and the postsynaptic density, suggesting that N-cadherin contributes to the assembly of the synaptic complex. To examine whether N-cadherin homotypic binding regulates the cell surface localization of nicotinic receptors, this study used heterologous expression of N-cadherin and ?3?4 nAChR subunits C-terminally fused to a myc-tag epitope in Chinese hamster ovary cells. Expression levels of ?3?4 nAChRs at cell-cell contacts and at contact-free cell membrane were analyzed by confocal microscopy. ?3?4 nAChRs were found distributed over the entire surface of contacting cells lacking N-cadherin. In contrast, N-cadherin-mediated cell-cell contacts were devoid of ?3?4 nAChRs. Cell-cell contacts mediated by N-cadherin-deleted proteins lacking the ?-catenin binding region or the entire cytoplasmic domain showed control levels of ?3?4 nAChRs expression. Inhibition of actin polymerization with latrunculin A and cytochalasin D did not affect ?3?4 nAChRs localization within N-cadherin-mediated cell-cell contacts. However, treatment with the Rho associated kinase inhibitor Y27632 resulted in a significant increase in ?3?4 nAChR levels within N-cadherin-mediated cell-cell contacts. Analysis of ?3?4 nAChRs localization in polarized Caco-2 cells showed specific expression on the apical cell membrane and colocalization with apical F-actin and the actin nucleator Arp3. These results indicate that actomyosin contractility downstream of N-cadherin homotypic binding regulates the cell surface localization of ?3?4 nAChRs presumably through interactions with a particular pool of F-actin.

Bruses, Juan L.

2013-01-01

33

Exogenous Expression of N-Cadherin in Breast Cancer Cells Induces Cell Migration, Invasion, and Metastasis  

Microsoft Academic Search

E- and N-cadherin are calcium-dependent cell adhesion molecules that mediate cell-cell adhesion and also modulate cell migration and tumor invasive- ness. The loss of E-cadherin-mediated adhesion has been shown to play an important role in the transition of epithelial tumors from a benign to an invasive state. However, recent evidence indicates that another mem- ber of the cadherin family, N-cadherin,

Rachel B. Hazan; Greg R. Phillips; Rui Fang Qiao; Larry Norton; Stuart A. Aaronson

2000-01-01

34

Compensatory redistribution of neuroligins and N-cadherin following deletion of synaptic ?1-integrin  

PubMed Central

?1-containing integrins are required for persistent synaptic potentiation in hippocampus and regulate hippocampal-dependent learning. Based largely on indirect evidence, there is a prevailing assumption that ?1-integrins are localized at synapses, where they contribute to synapse adhesion and signaling, but this has not been examined directly. Here, we investigate the fine localization of ?1-integrin in adult mouse hippocampus using high-resolution immunogold labeling, with a particular emphasis on synaptic labeling patterns. We find that ?1-integrins localize to synapses in CA1 and are concentrated postsynaptically. At the postsynaptic membrane, ?1-integrins are found more commonly clustered near active zone centers rather than at the peripheral edges. In mice harboring a conditional deletion of ?1-integrins, labeling for N-cadherin and Neuroligins increases. Western blots show increased levels of N-cadherin in total lysates and Neuroligins increase selectively in synaptosomes. These data suggest there is a dynamic, compensatory adjustment of synaptic adhesion. Such adjustment is specific only for certain cell adhesion molecules (CAMs), because labeling for SynCAM is unchanged. Together our findings demonstrate unequivocally that ?1-integrin is an integral synaptic adhesion protein, and suggest that adhesive function at the synapse reflects a cooperative and dynamic network of multiple CAM families.

Mortillo, Steven; Elste, Alice; Ge, Yongchao; Patil, Shekhar B.; Hsiao, Kuangfu; Huntley, George W.; Davis, Ronald L.; Benson, Deanna L.

2012-01-01

35

Compensatory redistribution of neuroligins and N-cadherin following deletion of synaptic ?1-integrin.  

PubMed

?1-containing integrins are required for persistent synaptic potentiation in hippocampus and regulate hippocampal-dependent learning. Based largely on indirect evidence, there is a prevailing assumption that ?1-integrins are localized at synapses, where they contribute to synapse adhesion and signaling, but this has not been examined directly. Here we investigate the fine localization of ?1-integrin in adult mouse hippocampus using high-resolution immunogold labeling, with a particular emphasis on synaptic labeling patterns. We find that ?1-integrins localize to synapses in CA1 and are concentrated postsynaptically. At the postsynaptic membrane, ?1-integrins are found more commonly clustered near active zone centers rather than at the peripheral edges. In mice harboring a conditional deletion of ?1-integrins, labeling for N-cadherin and neuroligins increases. Western blots show increased levels of N-cadherin in total lysates and neuroligins increase selectively in synaptosomes. These data suggest there is a dynamic, compensatory adjustment of synaptic adhesion. Such adjustment is specific only for certain cell adhesion molecules (CAMs), because labeling for SynCAM is unchanged. Together, our findings demonstrate unequivocally that ?1-integrin is an integral synaptic adhesion protein, and suggest that adhesive function at the synapse reflects a cooperative and dynamic network of multiple CAM families. PMID:22488504

Mortillo, Steven; Elste, Alice; Ge, Yongchao; Patil, Shekhar B; Hsiao, Kuangfu; Huntley, George W; Davis, Ronald L; Benson, Deanna L

2012-06-15

36

A novel o-naphtoquinone inhibits N-cadherin expression and blocks melanoma cell invasion via AKT signaling.  

PubMed

The down-regulation or loss of epithelial markers is often accompanied by the up-regulation of mesenchymal markers. E-cadherin generally suppresses invasiveness, whereas N-cadherin promotes invasion and metastasis in vitro. The aim of this work is to investigate the role of biflorin, a naphthoquinone with proven anticancer properties, on the expression of N-cadherin and AKT proteins in MDA-MB-435 invasive melanoma cancer cells after 12h of exposure to 1, 2.5 and 5?M biflorin. Biflorin inhibited MDA-MB-435 invasion in a dose-dependent manner (p<0.01). Likewise, biflorin down-regulated N-cadherin and AKT-1 expression in a dose-dependent manner. Biflorin did not inhibit the adhesion of MDA-MB-435 cells to any tested substrates. Additionally, biflorin blocked the invasiveness of cells by down-regulating N-cadherin, most likely via AKT-1 signaling. As such, biflorin may be a novel anticancer agent and a new prototype for drug design. PMID:23912027

Montenegro, Raquel Carvalho; de Vasconcellos, Marne Carvalho; Barbosa, Gleyce Dos Santos; Burbano, Rommel M R; Souza, Luciana G S; Lemos, Telma L G; Costa-Lotufo, Letícia V; de Moraes, Manoel Odorico

2013-08-01

37

N-Cadherin–Catenin Interaction: Necessary Component of Cardiac Cell Compartmentalization during Early Vertebrate Heart Development  

Microsoft Academic Search

During early heart development the expression pattern of N-cadherin, a calcium-dependent cell adhesion molecule, suggests its involvement in morphoregulation and the stabilization of cardiomyocyte differentiation. N-cadherin's adhesive activity is dependent upon its interaction with the intracellular catenins. An association with ?-catenin and ?-catenin also is believed to be involved in cell signaling. This study details the expression patterns of ?-catenin,

Kersti K. Linask; Karen A. Knudsen; Yong-Hao Gui

1997-01-01

38

GSK3? inhibition blocks melanoma cell/host interactions by downregulating N-cadherin expression and decreasing FAK phosphorylation  

PubMed Central

This study addresses the role of glycogen synthase kinase (GSK)-3? signaling in the tumorigenic behavior of melanoma. Immunohistochemical staining revealed GSK3? to be focally expressed in the invasive portions of 12% and 33% of primary and metastatic melanomas, respectively. GSK3 inhibitors and siRNA knockdown of GSK3? were found to inhibit the motile behavior of melanoma cells in scratch wound, 3D collagen implanted spheroid and modified Boyden chamber assays. Functionally, inhibition of GSK3? signaling was found to suppress N-cadherin expression at the mRNA and protein levels and was associated with decreased expression of the transcription factor Slug. Pharmacological and genetic ablation of GSK3? signaling inhibited the adhesion of melanoma cells to both endothelial cells and fibroblasts and prevented transendothelial migration, an effect rescued by the forced overexpression of N-cadherin. A further role for GSK3? signaling in invasion was suggested by the ability of GSK3? inhibitors and siRNA knockdown to block phosphorylation of FAK and increase the size of focal adhesions. In summary, we have demonstrated a previously unreported role for GSK3? in modulating the motile and invasive behavior of melanoma cells through N-cadherin and FAK. These studies suggest the potential therapeutic utility of inhibiting GSK3? in defined subsets of melanoma.

John, Jobin K.; Paraiso, Kim H.T.; Rebecca, Vito W.; Cantini, Liliana P.; Abel, Ethan V.; Pagano, Nicholas; Meggers, Eric; Mathew, Rahel; Krepler, Clemens; Izumi, Victoria; Fang, Bin; Koomen, John M.; Messina, Jane L.; Herlyn, Meenhard; Smalley, Keiran S. M.

2012-01-01

39

The Nonreceptor Protein Tyrosine Phosphatase PTP1B Binds to the Cytoplasmic Domain of N-Cadherin and Regulates the Cadherin-Actin Linkage  

Microsoft Academic Search

Cadherin-mediated adhesion depends on the association of its cytoplasmic domain with the actin- containing cytoskeleton. This interaction is mediated by a group of cytoplasmic proteins: a -and b - or g - cate- nin. Phosphorylation of b -catenin on tyrosine residues plays a role in controlling this association and, there- fore, cadherin function. Previous work from our labora- tory suggested

Janne Balsamo; Carlos Arregui; TinChung Leung; Jack Lilien

1998-01-01

40

Prognostic Significance of Twist and N-Cadherin Expression in NSCLC  

PubMed Central

Background Metastasis is the most common cause of disease failure and mortality for non-small cell lung cancer after surgical resection. Twist has been recently identified as a putative oncogene and a key regulator of carcinoma metastasis. N-cadherin is associated with a more aggressive behavior of cell lines and tumors. The aim of this study was to evaluate the clinical relevance of Twist and N-cadherin expression in NSCLC, and the effects of Twist1 knockdown on lung cancer cells. Methods We examined the expressions of Twist and N-cadherin by immunohistochemistry in 120 cases of non-small cell lung cancer (including 68 cases with follow-up records). We also analyzed Twist1 and N-cadherin mRNA expression in 30 non-small cell lung cancer tissues using quantitative reverse transcription polymerase chain reaction. The functional roles of Twist1 in lung cancer cell lines were evaluated by small interfering RNA-mediated depletion of the protein followed by analyses of cell apoptosis and invasion. Results In lung cancer tissues, the overexpression rate of Twist was 38.3% in lung cancer tissues. Overexpression of N-cadherin was shown in 40.83% of primary tumors. Moreover, Twist1 mRNA expression levels correlated with N-cadherin mRNA levels. Furthermore, overexpression of Twist1 or N-cadherin in primary non-small cell lung cancers was associated with a shorter overall survival (P<0.01, P<0.01, respectively). Depleting Twist expression inhibited cell invasion and increased apoptosis in lung cancer cell lines. Conclusions The overexpression of Twist and N-cadherin could be considered as useful biomarkers for predicting the prognosis of NSCLC. Twist1 could inhibit apoptosis and promote the invasion of lung cancer cells, and depletion of Twist1 in lung cancer cells led to inhibition of N-cadherin expression.

Hui, Linping; Zhang, Siyang; Dong, Xinjun; Tian, Dali; Cui, Zeshi; Qiu, Xueshan

2013-01-01

41

N-Cadherin and Integrins: Two Receptor Systems That Mediate Neuronal Process Outgrowth on Astrocyte Surfaces  

PubMed Central

Summary Receptor-mediated interactions between neurons and astroglia are likely to play a crucial role in the growth and guidance of CNS axons. Using antibodies to neuronal cell surface proteins, we identified two receptor systems mediating neurite outgrowth on cultured astrocytes. N-cadherin, a Ca2+-dependent cell adhesion molecule, functions prominently in the outgrowth of neurites on astrocytes by E8 and E14 chick ciliary ganglion (CC) neurons. ?1-class integrin ECM receptor heterodimers function less prominently in E8 and not at all in E14 neurite outgrowth on astrocytes. The lack of effect of integrin ?1 antibodies on E14 neurite outgrowth reflects an apparent loss of integrin function, as assayed by E14 neuronal attachment and process outgrowth on laminin. N-CAM appeared not to be required for neurite outgrowth by either E8 or E14 neurons. Since N-cadherin and integrin ?1 antibodies together virtually eliminated E8 CG neurite outgrowth on cultured astrocytes, these two neuronal receptors are probably important in regulating axon growth on astroglia in vivo.

Tomaselli, Kevin J.; Neugebauer, Karla M.; Bixby, John L.; Lilien, Jack; Reichardt, Louis F.

2009-01-01

42

N-Cadherin Extracellular Repeat 4 Mediates Epithelial to Mesenchymal Transition and Increased Motility  

PubMed Central

E- and N-cadherin are members of the classical cadherin family of proteins. E-cadherin plays an important role in maintaining the normal phenotype of epithelial cells. Previous studies from our laboratory and other laboratories have shown that inappropriate expression of N-cadherin by tumor cells derived from epithelial tissue results in conversion of the cell to a more fibroblast-like cell, with increased motility and invasion. Our present study was designed to determine which domains of N-cadherin make it different from E-cadherin, with respect to altering cellular behavior, such as which domains are responsible for the epithelial to mesenchymal transition and increased cell motility and invasion. To address this question, we constructed chimeric cadherins comprised of selected domains of E- and N-cadherin. The chimeras were transfected into epithelial cells to determine their effect on cell morphology and cellular behavior. We found that a 69–amino acid portion of EC-4 of N-cadherin was necessary and sufficient to promote both an epithelial to mesenchymal transition in squamous epithelial cells and increased cell motility. Here, we show that different cadherin family members promote different cellular behaviors. In addition, we identify a novel activity that can be ascribed to the extracellular domain of N-cadherin.

Kim, Jae-Beom; Islam, Shahidul; Kim, Young J.; Prudoff, Ryan S.; Sass, Kristin M.; Wheelock, Margaret J.; Johnson, Keith R.

2000-01-01

43

Monoclonal antibody targeting of N-cadherin inhibits prostate cancer growth, metastasis and castration resistance  

PubMed Central

The transition from androgen-dependent to castration-resistant prostate cancer (CRPC) is a lethal event of uncertain molecular etiology. Comparing gene expression in isogenic androgen-dependent and CRPC xenografts, we found a reproducible increase in N-cadherin expression, which was also elevated in primary and metastatic tumors of individuals with CRPC. Ectopic expression of N-cadherin in nonmetastatic, androgen-dependent prostate cancer models caused castration resistance, invasion and metastasis. Monoclonal antibodies against the ectodomain of N-cadherin reduced proliferation, adhesion and invasion of prostate cancer cells in vitro. In vivo, these antibodies slowed the growth of multiple established CRPC xenografts, blocked local invasion and metastasis and, at higher doses, led to complete regression. N-cadherin–specific antibodies markedly delayed the time to emergence of castration resistance, markedly affected tumor histology and angiogenesis, and reduced both AKT serine-threonine kinase activity and serum interleukin-8 (IL-8) secretion. These data indicate that N-cadherin is a major cause of both prostate cancer metastasis and castration resistance. Therapeutic targeting of this factor with monoclonal antibodies may have considerable clinical benefit.

Tanaka, Hiroshi; Kono, Evelyn; Tran, Chau P; Miyazaki, Hideyo; Yamashiro, Joyce; Shimomura, Tatsuya; Fazli, Ladan; Wada, Robert; Huang, Jiaoti; Vessella, Robert L; An, Jaibin; Horvath, Steven; Gleave, Martin; Rettig, Matthew B; Wainberg, Zev A; Reiter, Robert E

2011-01-01

44

Monoclonal antibody targeting of N-cadherin inhibits prostate cancer growth, metastasis and castration resistance.  

PubMed

The transition from androgen-dependent to castration-resistant prostate cancer (CRPC) is a lethal event of uncertain molecular etiology. Comparing gene expression in isogenic androgen-dependent and CRPC xenografts, we found a reproducible increase in N-cadherin expression, which was also elevated in primary and metastatic tumors of individuals with CRPC. Ectopic expression of N-cadherin in nonmetastatic, androgen-dependent prostate cancer models caused castration resistance, invasion and metastasis. Monoclonal antibodies against the ectodomain of N-cadherin reduced proliferation, adhesion and invasion of prostate cancer cells in vitro. In vivo, these antibodies slowed the growth of multiple established CRPC xenografts, blocked local invasion and metastasis and, at higher doses, led to complete regression. N-cadherin-specific antibodies markedly delayed the time to emergence of castration resistance, markedly affected tumor histology and angiogenesis, and reduced both AKT serine-threonine kinase activity and serum interleukin-8 (IL-8) secretion. These data indicate that N-cadherin is a major cause of both prostate cancer metastasis and castration resistance. Therapeutic targeting of this factor with monoclonal antibodies may have considerable clinical benefit. PMID:21057494

Tanaka, Hiroshi; Kono, Evelyn; Tran, Chau P; Miyazaki, Hideyo; Yamashiro, Joyce; Shimomura, Tatsuya; Fazli, Ladan; Wada, Robert; Huang, Jiaoti; Vessella, Robert L; An, Jaibin; Horvath, Steven; Gleave, Martin; Rettig, Matthew B; Wainberg, Zev A; Reiter, Robert E

2010-11-07

45

Protocadherin-19 and N-cadherin interact to control cell movements during anterior neurulation  

PubMed Central

The protocadherins comprise the largest subgroup within the cadherin superfamily, yet their cellular and developmental functions are not well understood. In this study, we demonstrate that pcdh19 (protocadherin 19) acts synergistically with n-cadherin (ncad) during anterior neurulation in zebrafish. In addition, Pcdh19 and Ncad interact directly, forming a protein–protein complex both in vitro and in vivo. Although both molecules are required for calcium-dependent adhesion in a zebrafish cell line, the extracellular domain of Pcdh19 does not exhibit adhesive activity, suggesting that the involvement of Pcdh19 in cell adhesion is indirect. Quantitative analysis of in vivo two-photon time-lapse image sequences reveals that loss of either pcdh19 or ncad impairs cell movements during neurulation, disrupting both the directedness of cell movements and the coherence of movements among neighboring cells. Our results suggest that Pcdh19 and Ncad function together to regulate cell adhesion and to mediate morphogenetic movements during brain development.

Biswas, Sayantanee; Emond, Michelle R.

2010-01-01

46

Biogenesis of N-Cadherin-dependent Cell-Cell Contacts in Living Fibroblasts Is a Microtubule-dependent Kinesin-driven MechanismV?  

PubMed Central

Cadherin-mediated cell-cell adhesion is a dynamic process that is regulated during embryonic development, cell migration, and differentiation. Different cadherins are expressed in specific tissues consistent with their roles in cell type recognition. In this study, we examine the formation of N-cadherin–dependent cell-cell contacts in fibroblasts and myoblasts. In contrast to E-cadherin, both endogenous and ectopically expressed N-cadherin shuttles between an intracellular and a plasma membrane pool. Initial formation of N-cadherin–dependent cell-cell contacts results from the recruitment of the intracellular pool of N-cadherin to the plasma membrane. N-cadherin also localizes to the Golgi apparatus and both secretory and endocytotic vesicles. We demonstrate that the intracellular pool of N-cadherin is tightly associated with the microtubule (MT) network and that junction formation requires MTs. In addition, localization of N-cadherin to the cortex is dependent on an intact F-actin cytoskeleton. We show that N-cadherin transport requires the MT network as well as the activity of the MT-associated motor kinesin. In conclusion, we propose that N-cadherin distribution is a regulated process promoted by cell-cell contact formation, which controls the biogenesis and turnover of the junctions through the MT network.

Mary, Sophie; Charrasse, Sophie; Meriane, Mayya; Comunale, Franck; Travo, Pierre; Blangy, Anne; Gauthier-Rouviere, Cecile

2002-01-01

47

N-cadherin modulates voltage activated calcium influx via RhoA, p120-catenin, and myosinactin interaction  

PubMed Central

N-cadherin is a transmembrane adhesion receptor that contributes to neuronal development and synapse formation through homophilic interactions that provide structural-adhesive support to contacts between cell membranes. In addition, N-cadherin homotypic binding may initiate cell signaling that regulates neuronal physiology. In this study, we investigated signaling capabilities of N-cadherin that control voltage activated calcium influx. Using whole-cell voltage clamp recording of isolated inward calcium currents in freshly isolated chick ciliary ganglion neurons we show that the juxtamembrane region of N-cadherin cytoplasmic domain regulates high-threshold voltage activated calcium currents by interacting with p120-catenin and activating RhoA. This regulatory mechanism requires myosin interaction with actin. Furthermore, N-cadherin homophilic binding enhanced voltage activated calcium current amplitude in dissociated neurons that have already developed mature synaptic contacts in vivo. The increase in calcium current amplitude was not affected by brefeldin A suggesting that the effect is caused via direct channel modulation and not by increasing channel expression. In contrast, homotypic N-cadherin interaction failed to regulate calcium influx in freshly isolated immature neurons. However, RhoA inhibitors enhanced calcium current amplitude in these immature neurons, suggesting that the inhibitory effect of RhoA on calcium entry is regulated during neuronal development and synapse maturation. These results indicate that N-cadherin modulates voltage activated calcium entry by a mechanism that involves RhoA activity and its downstream effects on the cytoskeleton, and suggest that N-cadherin provides support for synaptic maturation and sustained synaptic activity by facilitating voltage activated calcium influx.

Marrs, Glen S.; Theisen, Christopher S.; Bruses, Juan L.

2010-01-01

48

N-cadherin adherens junctions mediate osteogenesis through PI3K signaling.  

PubMed

During endochondral ossification, the cartilage is surrounded by a layer of cells that constitute the perichondrium. Communication between osteoblasts in the perichondrium via N-cadherin adherens junctions is essential for endochondral bone growth. We observed that adherens junction molecule N-cadherin and its interacting partners p120, ?-catenin and PTEN are expressed by cells present in the perichondrium. To study if N-cadherin mediated adherens junctions play a role in mediating signal transduction events during bone development, we utilized MC3T3E1 preosteoblasts plated at sub confluent (low) and confluent (high) densities to mimic adherens junction formation. When MC3T3E1 cells were plated at high density we observed an increase in phosphorylation of AKTSer473 and its downstream target GSK3Ser9, which coincided with an increase in Osterix, Osteomodulin and Osteoglycin gene expression. Using immunofluorescence, we identified N-cadherin, p120 and ?-catenin localized at the membrane of MC3T3E1 cells. Treatment of confluent MC3T3E1 cells with an N-cadherin junction inhibitor-EGTA and a PI3K inhibitor LY294002 resulted in reduction of phosphorylation levels of AKT and GSK3 and expression of Osterix, Osteomodulin and Osteoglycin. Furthermore, utilizing an N-cadherin blocking antibody resulted in reduced AKT signaling and Osterix gene expression, suggesting that osteoblast junction formation is linked to activation of PI3K signaling, which leads to osteoblast differentiation. To further explore the strength of this linkage, we utilized a conditional knockout approach using Dermo1cre to delete ?-catenin and PTEN, two important proteins known to be essential for adherens junctions and PI3K signaling, respectively. In the absence of ?-catenin, we observed a decrease in adherens junctions and AKT signaling in the perichondrium. PTEN deletion, on the other hand, increased the number of cells expressing N-cadherin in the perichondrium. These observations show that N-cadherin mediated junctions between osteoblasts are needed for osteoblast gene transcription. PMID:21964322

Guntur, Anyonya R; Rosen, Clifford J; Naski, Michael C

2011-09-16

49

N-cadherin adherens junctions mediate osteogenesis through PI3K signaling  

PubMed Central

During endochondral ossification, the cartilage is surrounded by a layer of cells that constitute the perichondrium. Communication between osteoblasts in the perichondrium via N-cadherin adherens junctions is essential for endochondral bone growth. We observed that adherens junction molecule N-cadherin and its interacting partners p120, ?-catenin and PTEN are expressed by cells present in the perichondrium. To study if N-cadherin mediated adherens junctions play a role in mediating signal transduction events during bone development, we utilized MC3T3E1 preosteoblasts plated at sub confluent (low) and confluent (high) densities to mimic adherens junction formation. When MC3T3E1 cells were plated at high density we observed an increase in phosphorylation of AKTSer473 and its downstream target GSK3Ser9, which coincided with an increase in Osterix, Osteomodulin and Osteoglycin gene expression. Using immunofluorescence, we identified N-cadherin, p120 and ?-catenin localized at the membrane of MC3T3E1 cells. Treatment of confluent MC3T3E1cells with an N-cadherin junction inhibitor-EGTA and a PI3K inhibitor LY294002 resulted in reduction of phosphorylation levels of AKT and GSK3 and expression of Osterix, Osteomodulin and Osteoglycin. Furthermore, utilizing an N-cadherin blocking antibody resulted in reduced AKT signaling and Osterix gene expression, suggesting that osteoblast junction formation is linked to activation of PI3K signaling, which leads to osteoblast differentiation. To further explore the strength of this linkage, we utilized a conditional knockout approach using Dermo1cre to delete ?-catenin and PTEN, two important proteins known to be essential for adherens junctions and PI3K signaling, respectively. In the absence of ?-catenin, we observed a decrease in adherens junctions and AKT signaling in the perichondrium. PTEN deletion, on the other hand, increased the number of cells expressing N-cadherin in the perichondrium. These observations show that N-cadherin mediated junctions between osteoblasts are needed for osteoblast gene transcription.

Guntur, Anyonya R; Rosen, Clifford J; Naski, Michael C

2011-01-01

50

Electric impedance sensing during the inhibition of cell-cell adhesion.  

PubMed

Electric cell impedance sensing (ECIS) was used to monitor the change of in vitro neuron-neuron adhesion in response to the blocking of N-Cam, N-Cadherin and L1. ECIS is a method in which cell morphology and cell mobility can be indirectly measured by changes in intercellular resistance. Antibodies and soluble extracellular domains of the cell adhesion molecules N-Cam, N-Cadherin and L1 were used as blockers of these adhesion molecules on the cell surface. In a 96 hour aggregation assay on a low adhesive substrate, the effect of mentioned blockers on the aggregation was investigated. The N-Cadherin antibody showed effective in aggregation inhibition at concentrations of 3 and 10 micrograms/ml. Up to 96 hours no aggregation occurred. A similar effect was achieved by the N-Cadherin protein, although less distinct. Blocking of N-CAM and L1 revealed no inhibition of aggregation. Results from impedance measurements correspond to those of the aggregation assays. The neuron-neuron adhesion in monolayers was inhibited by blocking of cell adhesion molecules and monitored by ECIS. Impedances of neuron covered electrodes were significantly lower in the presence of N-Cadherin antibody and protein at concentrations of 1, 3 and 10 micrograms/ml, indicating a less profound binding between adjacent neuron.The results from both the aggregation assays and the impedance measurements demonstrate the applicability of CAM blocking for the regulation of culture topography. PMID:19163088

Wiertz, R F; Rutten, W C; Marani, E

2008-01-01

51

N-cadherin specifies first asymmetry in developing neurons  

PubMed Central

The precise polarization and orientation of developing neurons is essential for the correct wiring of the brain. In pyramidal excitatory neurons, polarization begins with the sprouting of opposite neurites, which later define directed migration and axo-dendritic domains. We here show that endogenous N-cadherin concentrates at one pole of the newborn neuron, from where the first neurite subsequently emerges. Ectopic N-cadherin is sufficient to favour the place of appearance of the first neurite. The Golgi and centrosome move towards this newly formed morphological pole in a second step, which is regulated by PI3K and the actin/microtubule cytoskeleton. Moreover, loss of function experiments in vivo showed that developing neurons with a non-functional N-cadherin misorient their cell axis. These results show that polarization of N-cadherin in the immediate post-mitotic stage is an early and crucial mechanism in neuronal polarity.

Gartner, Annette; Fornasiero, Eugenio F; Munck, Sebastian; Vennekens, Krist'l; Seuntjens, Eve; Huttner, Wieland B; Valtorta, Flavia; Dotti, Carlos G

2012-01-01

52

N-cadherin specifies first asymmetry in developing neurons.  

PubMed

The precise polarization and orientation of developing neurons is essential for the correct wiring of the brain. In pyramidal excitatory neurons, polarization begins with the sprouting of opposite neurites, which later define directed migration and axo-dendritic domains. We here show that endogenous N-cadherin concentrates at one pole of the newborn neuron, from where the first neurite subsequently emerges. Ectopic N-cadherin is sufficient to favour the place of appearance of the first neurite. The Golgi and centrosome move towards this newly formed morphological pole in a second step, which is regulated by PI3K and the actin/microtubule cytoskeleton. Moreover, loss of function experiments in vivo showed that developing neurons with a non-functional N-cadherin misorient their cell axis. These results show that polarization of N-cadherin in the immediate post-mitotic stage is an early and crucial mechanism in neuronal polarity. PMID:22354041

Gärtner, Annette; Fornasiero, Eugenio F; Munck, Sebastian; Vennekens, Krist'l; Seuntjens, Eve; Huttner, Wieland B; Valtorta, Flavia; Dotti, Carlos G

2012-02-21

53

Local N-cadherin interactions mediate distinct steps in the targeting of lamina neurons  

PubMed Central

Summary The organisation of neuronal processes into series of layers is a hallmark of many brain regions. Homophilic cell adhesion molecules of the cadherin family have been implicated in layer choice. How they contribute to the targeting of neurons to distinct layers remains unclear. Here we systematically explore the role of a classical cadherin, Drosophila N-cadherin (CadN), in the targeting of five classes of related neurons to a series of consecutive layers in the fly visual system. We show that CadN is required in lamina neurons at discrete developmental steps but not used in a layer-specific fashion. Local CadN expression patterns correlate with specific growth cone movements and CadN expression on one growth cone in a specific layer is essential for targeting of processes of another neuron to this layer. We propose that dynamic regulation of CadN enables this widely expressed protein to mediate specific local interactions during neural circuit assembly.

Nern, Aljoscha; Zhu, Yan; Zipursky, S. Lawrence

2009-01-01

54

Opposite roles of furin and PC5A in N-cadherin processing.  

PubMed

We recently demonstrated that lack of Furin-processing of the N-cadherin precursor (proNCAD) in highly invasive melanoma and brain tumor cells results in the cell-surface expression of a nonadhesive protein favoring cell migration and invasion in vitro. Quantitative polymerase chain reaction analysis of malignant human brain tumor cells revealed that of all proprotein convertases (PCs) only the levels of Furin and PC5A are modulated, being inversely (Furin) or directly (PC5A) correlated with brain tumor invasive capacity. Intriguingly, the N-terminal sequence following the Furin-activated NCAD site (RQKR?DW(161), mouse nomenclature) reveals a second putative PC-processing site (RIRSDR?DK(189)) located in the first extracellular domain. Cleavage at this site would abolish the adhesive functions of NCAD because of the loss of the critical Trp(161). This was confirmed upon analysis of the fate of the endogenous prosegment of proNCAD in human malignant glioma cells expressing high levels of Furin and low levels of PC5A (U343) or high levels of PC5A and negligible Furin levels (U251). Cellular analyses revealed that Furin is the best activating convertase releasing an ~17-kDa prosegment, whereas PC5A is the major inactivating enzyme resulting in the secretion of an ~20-kDa product. Like expression of proNCAD at the cell surface, cleavage of the NCAD molecule at RIRSDR?DK(189) renders the U251 cancer cells less adhesive to one another and more migratory. Our work modifies the present view on posttranslational processing and surface expression of classic cadherins and clarifies how NCAD possesses a range of adhesive potentials and plays a critical role in tumor progression. PMID:23097623

Maret, Deborah; Sadr, Mohamad Seyed; Sadr, Emad Seyed; Colman, David R; Del Maestro, Rolando F; Seidah, Nabil G

2012-10-01

55

Opposite Roles of Furin and PC5A in N-Cadherin Processing12  

PubMed Central

We recently demonstrated that lack of Furin-processing of the N-cadherin precursor (proNCAD) in highly invasive melanoma and brain tumor cells results in the cell-surface expression of a nonadhesive protein favoring cell migration and invasion in vitro. Quantitative polymerase chain reaction analysis of malignant human brain tumor cells revealed that of all proprotein convertases (PCs) only the levels of Furin and PC5A are modulated, being inversely (Furin) or directly (PC5A) correlated with brain tumor invasive capacity. Intriguingly, the N-terminal sequence following the Furin-activated NCAD site (RQKR?DW161, mouse nomenclature) reveals a second putative PC-processing site (RIRSDR?DK189) located in the first extracellular domain. Cleavage at this site would abolish the adhesive functions of NCAD because of the loss of the critical Trp161. This was confirmed upon analysis of the fate of the endogenous prosegment of proNCAD in human malignant glioma cells expressing high levels of Furin and low levels of PC5A (U343) or high levels of PC5A and negligible Furin levels (U251). Cellular analyses revealed that Furin is the best activating convertase releasing an ?17-kDa prosegment, whereas PC5A is the major inactivating enzyme resulting in the secretion of an ?20-kDa product. Like expression of proNCAD at the cell surface, cleavage of the NCAD molecule at RIRSDR?DK189 renders the U251 cancer cells less adhesive to one another and more migratory. Our work modifies the present view on posttranslational processing and surface expression of classic cadherins and clarifies how NCAD possesses a range of adhesive potentials and plays a critical role in tumor progression.

Maret, Deborah; Sadr, Mohamad Seyed; Sadr, Emad Seyed; Colman, David R; Del Maestro, Rolando F; Seidah, Nabil G

2012-01-01

56

N-cadherin and cadherin 11 modulate postnatal bone growth and osteoblast differentiation by distinct mechanisms  

PubMed Central

We have previously shown that targeted expression of a dominant-negative truncated form of N-cadherin (Cdh2) delays acquisition of peak bone mass in mice and retards osteoblast differentiation; whereas deletion of cadherin 11 (Cdh11), another osteoblast cadherin, leads to only modest osteopenia. To determine the specific roles of these two cadherins in the adult skeleton, we generated mice with an osteoblast/osteocyte specific Cdh2 ablation (cKO) and double Cdh2+/?;Cdh11?/? germline mutant mice. Age-dependent osteopenia and smaller diaphyses with decreased bone strength characterize cKO bones. By contrast, Cdh2+/?;Cdh11?/? exhibit severely reduced trabecular bone mass, decreased in vivo bone formation rate, smaller diaphyses and impaired bone strength relative to single Cdh11 null mice. The number of bone marrow immature precursors and osteoprogenitor cells is reduced in both cKO and Cdh2+/?;Cdh11?/? mice, suggesting that N-cadherin is involved in maintenance of the stromal cell precursor pool via the osteoblast. Although Cdh11 is dispensable for postnatal skeletal growth, it favors osteogenesis over adipogenesis. Deletion of either cadherin reduces ?-catenin abundance and ?-catenin-dependent gene expression, whereas N-cadherin loss disrupts cell-cell adhesion more severely than loss of cadherin 11. Thus, Cdh2 and Cdh11 are crucial regulators of postnatal skeletal growth and bone mass maintenance, serving overlapping, yet distinct, functions in the osteogenic lineage.

Di Benedetto, Adriana; Watkins, Marcus; Grimston, Susan; Salazar, Valerie; Donsante, Christine; Mbalaviele, Gabriel; Radice, Glenn L.; Civitelli, Roberto

2010-01-01

57

Connexin43 Associated with an N-cadherin-containing Multiprotein Complex Is Required for Gap Junction Formation in NIH3T3 Cells  

Microsoft Academic Search

Previous studies have indicated an intimate linkage between gap junction and adherens junction formation. It was suggested this could reflect the close membrane- membrane apposition required for junction formation. In NIH3T3 cells, we observed the colocalization of con- nexin43 (Cx431) gap junction protein with N-cadherin, p120, and other N-cadherin-associated proteins at re- gions of cell-cell contact. We also found that

Chih-Jen Wei; Richard Francis; Xin Xu; Cecilia W. Lo

2005-01-01

58

The kinase domains of obscurin interact with intercellular adhesion proteins.  

PubMed

Obscurins comprise a family of giant (~870- to 600-kDa) and small (~250- to 55-kDa) proteins that play important roles in myofibrillogenesis, cytoskeletal organization, and cell adhesion and are implicated in hypertrophic cardiomyopathy and tumorigenesis. Giant obscurins are composed of tandem structural and signaling motifs, including 2 serine/threonine kinase domains, SK1 and SK2, present at the COOH terminus of giant obscurin-B. Using biochemical and cellular approaches, we show for the first time that both SK1 and SK2 possess enzymatic activities and undergo autophosphorylation. SK2 can phosphorylate the cytoplasmic domain of N-cadherin, a major component of adherens junctions, and SK1 can interact with the extracellular domain of the ?1-subunit of the Na(+)/K(+)-ATPase, which also resides in adherens junctions. Immunostaining of nonpermeabilized myofibers and cardiocytes revealed that some obscurin kinase isoforms localize extracellularly. Quantification of the exofacial expression of obscurin kinase proteins indicated that they occupy ~16 and ~5% of the sarcolemmal surface in myofibers and cardiocytes, respectively. Treatment of heart lysates with peptide-N-glycosidase F revealed that while giant obscurin-B localizes intracellularly, possessing dual kinase activity, a small obscurin kinase isoform that contains SK1 localizes extracellularly, where it undergoes N-glycosylation. Collectively, our studies demonstrate that the obscurin kinase domains are enzymatically active and may be involved in the regulation of cell adhesion. PMID:23392350

Hu, Li-Yen R; Kontrogianni-Konstantopoulos, Aikaterini

2013-02-07

59

Interleukin-6-induced Twist and N-cadherin enhance melanoma cell metastasis.  

PubMed

Melanoma patients frequently have elevated serum levels of interleukin-6 (IL-6), which is correlated with a poor prognosis. IL-6 activates STAT3 phosphorylation, inducing the transcription of genes that regulate tumor cell proliferation and antiapoptosis. In addition, recent evidence suggests that IL-6 induces the epithelial-to-mesenchymal transition and enhances the invasiveness of tumor cells of epithelial origin. However, it is unknown whether IL-6 affects mesenchymal tumor cells. In this study, we examined the effects of IL-6 on melanoma cells and found that IL-6 can enhance their metastatic potential by regulating the expression of Twist and N-cadherin. First, we confirmed that human melanoma tissues express IL-6 (especially at the lesion site), the IL-6 receptor, N-cadherin, and nuclear Twist. Next, we found that IL-6 induces STAT3 phosphorylation in WM-266-4 human melanoma cells, resulting in transient upregulation of Twist, which is a key regulator of metastasis. Importantly, the expression of N-cadherin, a protein downstream of Twist, was also increased on the cell surface after treatment with IL-6. These cells showed enhanced invasiveness, assessed using an invasion assay, and formed more metastatic nodules in the lungs of NOD-SCID mice after an intravenous injection. Importantly, melanoma cells with knocked-down N-cadherin formed less lung nodules compared with control in the NOD-SCID mouse model. Our data suggest that increased serum IL-6 in cancer patients could increase the invasiveness of melanoma cells and accelerate metastasis. Blocking IL-6 in the melanoma microenvironment may therefore inhibit disease progression. PMID:24051540

Na, Yi-Rang; Lee, Jin-Sub; Lee, Seok-Jong; Seok, Seung-Hyeok

2013-12-01

60

Identification of two structural types of calcium-dependent adhesion molecules in the chicken embryo.  

PubMed Central

By using an immunological and peptide mapping approach two calcium-dependent cell-cell adhesion molecules (calCAMs) in the embryonic chicken are compared. A third closely related molecule is identified and compared to the two calCAMs. One of the calCAMs appears to be identical to the previously identified adhesion molecule N-cadherin, originally identified in chicken retina and localized to neural tissues. The second is the same as L-CAM, originally identified in chicken liver but localized to a variety of epithelial tissues. The third, also found in liver, is similar to L-CAM but is much closer in structure to N-cadherin. It is, however, immunologically distinct from N-cadherin. We therefore refer to this newly identified molecule as CRM-L for cadherin-related molecule in liver. CRM-L, N-cadherin, and L-CAM are all cell-surface proteins with a similar stability to tryptic digestion in the presence of calcium. CRM-L has the same molecular mass and isoelectric point as N-cadherin but is distinct from L-CAM in these properties. Two-dimensional peptide maps of complete tryptic digests reveal that CRM-L shares 69% of its peptides with N-cadherin and 20% with L-CAM. On the basis of these data, we suggest that there are at least two distinguishable types of calCAMs in the chicken embryo: one represented by the closely related molecules N-cadherin and CRM-L, and another represented by L-CAM. Images

Crittenden, S L; Rutishauser, U; Lilien, J

1988-01-01

61

Hyaluronan suppresses prostate tumor cell proliferation through diminished expression of N-cadherin and aberrant growth factor receptor signaling  

PubMed Central

Hyaluronan (HA) production has been functionally implicated in prostate tumorigenesis and metastasis. We previously used prostate tumor cells overexpressing the HA synthesizing enzyme HAS3 or the clinically relevant hyaluronidase Hyal1 to show that excess HA production suppresses tumor growth, while HA turnover accelerates spontaneous metastasis from the prostate. Here, we examined pathways responsible for effects of HAS3 and Hyal1 on tumor cell phenotype. Detailed characterization of cell cycle progression revealed that expression of Hyal1 accelerated cell cycle re-entry following synchronization, whereas HAS3 alone delayed entry. Hyal1 expressing cells exhibited a significant reduction in their ability to sustain ERK phosphorylation upon stimulation by growth factors, and in their expression of the cyclin dependent kinase inhibitor p21. In contrast, HAS3 expressing cells showed prolonged ERK phosphorylation and increased expression of both p21 and p27, in asynchronous and synchronized cultures. Changes in cell cycle regulatory proteins were accompanied by HA-induced suppression of N-cadherin, while E-cadherin expression and ?-catenin expression and distribution remained unchanged. Our results are consistent with a model in which excess HA synthesis suppresses cell proliferation by promoting homotypic E-cadherin mediated cell-cell adhesion, consequently signaling to elevate cell cycle inhibitor expression and suppress G1 to S phase transition.

Bharadwaj, Alamelu G.; Goodrich, Nathaniel P.; McAtee, Caitlin O.; Haferbier, Katie; Oakley, Gregory G.; Wahl, James K.; Simpson, Melanie A.

2011-01-01

62

Oncologic trogocytosis with Hospicells induces the expression of N-cadherin by breast cancer cells.  

PubMed

In breast cancers, the appearance of metastasis is synonymous with poor prognosis. The metastatic process is usually associated with epithelial-mesenchymal transition (EMT) which is often induced by several soluble factors produced either by the tumour cells themselves or by cells constituting the tumour microenvironment. The aim of the present study was to determine whether the mesenchymal properties given by some molecules such as N-cadherin, for instance, could be acquired by cancer cells via the trogocytosis process with cells of the tumour microenvironment. Hospicells are stromal cells which were first isolated from cancer cell aggregates of patients with ovarian cancer. We recently showed that these cells are immunosuppressive for T lymphocyte functions and confer chemoresistance to cancer cells by the transfer of the MDR protein via trogocytosis. In this study, we showed that a mammary cancer cell line (MDA-MB-231) acquires patches of membrane via oncologic trogocytosis with Hospicells. This unidirectional and active process depends on actin polymerization and can be increased via inhibition of the Src family and decreased via inhibition of PI3K. Trogocytosis between Hospicells and MDA-MB-231 does not lead to the direct acquisition of N-cadherin but rather it leads to the production of soluble factor(s) which induce de novo expression of N-cadherin by the cancer cells. The novelty here is that this factor is produced only if cancer cells interact and undergo trogocytosis with Hospicells. This new expression could confer a more invasive phenotype to the cancer cells and thus can explain the correlation of the presence of Hospicells with the number of invaded lymph nodes in patients with mammary adenocarcinoma. PMID:21042713

Lis, Raphaël; Capdet, Jérome; Mirshahi, Pejman; Lacroix-Triki, Magali; Dagonnet, Francoise; Klein, Christophe; Mirshahi, Massoud; Fournié, Jean-Jacques; Rafii, Arash; Poupot, Mary

2010-12-01

63

A signaling pathway leading to metastasis is controlled by N-cadherin and the FGF receptor.  

PubMed

The intracellular signaling events causing tumor cells to become metastatic are not well understood. N-cadherin and FGF-2 synergistically increase migration, invasion, and secretion of extracellular proteases in breast tumor cells. Here, we define a metastatic signaling cascade activated by N-cadherin and FGF-2. In the presence of N-cadherin, FGF-2 caused sustained activation of the MAPK-ERK pathway, leading to MMP-9 gene transcription and cellular invasion. N-cadherin prevented the FGF receptor (FGFR) from undergoing ligand-induced internalization, resulting in increased FGFR-1 stability. Association of FGFR-1 with N-cadherin was mediated by the first two Ig-like domains of FGFR-1. These results suggest that protection of the FGFR-1 from ligand-induced downregulation by N-cadherin enhances receptor signaling and provides a mechanism by which tumor cells can acquire metastatic properties. PMID:12398894

Suyama, Kimita; Shapiro, Irina; Guttman, Mitchell; Hazan, Rachel B

2002-10-01

64

Axon sorting within the spinal cord marginal zone via Robo-mediated inhibition of N-cadherin controls spinocerebellar tract formation  

PubMed Central

The axons of spinal projection neurons transmit sensory information to the brain by ascending within highly organized longitudinal tracts. However, the molecular mechanisms that control the sorting of these axons within the spinal cord and their directed growth to poorly defined targets are not understood. Here, we show that an interplay between Robo and the cell adhesion molecule, N-cadherin, sorts spinal commissural axons into appropriate longitudinal tracts within the spinal cord, and thereby facilitates their brain targeting. Specifically, we show that d1 and d2 spinal commissural axons join the lateral funiculus within the spinal cord and target the cerebellum in chick embryos, and that these axons contribute to the spinocerebellar projection in transgenic reporter mice. Disabling Robo signaling or overexpressing N-cadherin on these axons prevents the formation of the lateral funiculus and the spinocerebellar tract, and simultaneously perturbing Robo and N-cadherin function rescues both phenotypes in chick embryos. Consistent with these observations, disabling Robo function in conditional N-cadherin knockout mice results in a wild type-like lateral funiculus. Together, these findings suggest that spinal projection axons must be sorted into distinct longitudinal tracts within the spinal cord proper to project to their brain targets.

Sakai, Nozomi; Insolera, Ryan; Sillitoe, Roy V.; Shi, Song-Hai; Kaprielian, Zaven

2012-01-01

65

IDENTIFICATION OF A NOVEL INTERMEDIATE FILAMENT-LINKED N-CADHERIN/?-CATENIN COMPLEX INVOLVED IN THE ESTABLISHMENT OF THE CYTOARCHITECTURE OF DIFFERENTIATED LENS FIBER CELLS  

PubMed Central

Tissue morphogenesis and maintenance of complex tissue architecture requires a variety of cell-cell junctions. Typically, cells adhere to one another through cadherin junctions, both adherens and desmosomal junctions, strengthened by association with cytoskeletal networks during development. Both ?- and ?-catenins are reported to link classical cadherins to the actin cytoskeleton, but only ?-catenin binds to the desmosomal cadherins, which links them to intermediate filaments through its association with desmoplakin. Here we provide the first biochemical evidence that, in vivo, ?-catenin also mediates interactions between classical cadherins and the intermediate filament cytoskeleton, linked through desmoplakin. In the developing lens, which has no desmosomes, we discovered that vimentin became linked to N-cadherin complexes in a differentiation-state specific manner. This newly identified junctional complex was tissue specific but not unique to the lens. To determine whether in this junction N-cadherin was linked to vimentin through ?-catenin or ?-catenin we developed an innovative “double” immunoprecipitation technique. This approach made possible, for the first time, the separation of N-cadherin/?-catenin from N-cadherin/?-catenin complexes and the identification of multiple members of each of these isolated protein complexes. The study revealed that vimentin was associated exclusively with N-cadherin/?-catenin junctions. Assembly of this novel class of cadherin junctions was coincident with establishment of the unique cytoarchitecture of lens fiber cells. In addition, ?-catenin had a distinctive localization to the vertices of these hexagonally shaped differentiating lens fiber cells, a region devoid of actin; while ?-catenin co-localized with actin at lateral cell interfaces. We believe this novel vimentin-linked N-cadherin/?-catenin junction provides the tensile strength necessary to establish and maintain structural integrity in tissues that lack desmosomes.

Leonard, Michelle; Chan, Yim; Menko, A. Sue

2008-01-01

66

N-cadherin in osteolineage cells is not required for maintenance of hematopoietic stem cells  

PubMed Central

There is evidence suggesting that N-cadherin expression on osteoblast lineage cells regulates hematopoietic stem cell (HSC) function and quiescence. To test this hypothesis, we conditionally deleted N-cadherin (Cdh2) in osteoblasts using Cdh2flox/flox Osx-Cre mice. N-cadherin expression was efficiently ablated in osteoblast lineage cells as assessed by mRNA expression and immunostaining of bone sections. Basal hematopoiesis is normal in these mice. In particular, HSC number, cell cycle status, long-term repopulating activity, and self-renewal capacity were normal. Moreover, engraftment of wild-type cells into N-cadherin–deleted recipients was normal. Finally, these mice responded normally to G-CSF, a stimulus that mobilizes HSCs by inducing alterations to the stromal micro-environment. In conclusion, N-cadherin expression in osteoblast lineage cells is dispensable for HSC maintenance in mice.

Greenbaum, Adam M.; Revollo, Leila D.; Woloszynek, Jill R.; Civitelli, Roberto

2012-01-01

67

N-Cadherin Signaling Potentiates Mammary Tumor Metastasis via Enhanced Extracellular Signal-Regulated Kinase Activation  

Microsoft Academic Search

N-cadherin is up-regulated in aggressive breast carcinomas, but its mechanism of action in vivo remains unknown. Transgenic mice coexpressing N-cadherin and polyomavirus middle T antigen (PyVmT)in the mammary epithelium displayed increased pulmonary metastasis, with no differences in tumor onset or growth relative to control PyVmT mice. PyVmT-N-cadherin tumors contained higher levels of phos- phorylated extracellular signal-regulated kinase (ERK)and p38 mitogen-activated

James Hulit; Kimita Suyama; Su Chung; Georgia Agiostratidou; Weisong Shan; Xinyuan Dong; Terence M. Williams; Michael P. Lisanti; Karen Knudsen; Rachel B. Hazan

2007-01-01

68

Inhibition of neuronal cell-cell adhesion measured by the microscopic aggregation assay and impedance sensing.  

PubMed

Microscopic aggregation assay and impedance sensing (IS) were used to monitor a change in in vitro neuron-neuron adhesion in response to blocking of cell adhesion molecules. By blocking neuron-neuron adhesion, migration and aggregation of neuronal cells can be inhibited. This leads to better control of spatial arrangement of cells in culture. In the literature N-CAM, L1 and N-cadherin proteins are pointed out as main regulators of neuronal adhesion. In this study, these three main cell adhesion molecules were used to inhibit neuron-to-neuron adhesion and aggregation. Both soluble extracellular domains and antigen antibodies were added to these adhesion molecules. They were investigated for their blocking ability in neuronal cultures. First, in a 96 h aggregation assay on a low-adhesive substrate, the effect of inhibition of the three proteins on aggregation of cortical neurons was investigated optically. Both L1 antibody and L1 protein had no effect on the degree of aggregation. An N-cadherin antibody however was shown to be effective in aggregation inhibition at concentrations of 1 and 3 µg ml(-1). Up to 96 h no aggregation occurred. A similar effect was achieved by the N-cadherin protein, although less distinct. N-CAM blocking revealed no inhibition of aggregation. Second, results from IS corresponded to those of the aggregation assays. In these experiments neuron-neuron adhesion was also inhibited by blocking N-CAM L1 and N-cadherin. Cortical neurons were cultured in small wells containing circular 100 µm diameter gold electrodes, so small changes in cell-cell interactions in monolayers of neurons could be monitored by IS. Impedances of neuron-covered electrodes were significantly lower in the presence of the N-cadherin antibody and protein at concentrations of 1, 3 and 10 µg ml(-1), indicating a less profound binding between adjacent neurons. Results from the aggregation assays and impedance measurements demonstrate the applicability of blocking cell adhesion molecules for inhibition of cell-cell adhesion and aggregation. PMID:20811090

Wiertz, R W F; Marani, E; Rutten, W L C

2010-09-01

69

Loss of DeltaNp63alpha promotes invasion of urothelial carcinomas via N-cadherin/Src homology and collagen/extracellular signal-regulated kinase pathway.  

PubMed

p63 plays a critical role in normal development and maintenance of stratified epithelia, including the urothelium. In the normal urothelium, urothelial cells in the basal layers abundantly express the predominant p63 isoform DeltaNp63alpha. We previously showed that (a) DeltaNp63alpha expression at the similar level to the normal urothelium is retained in most low-grade papillary noninvasive (LPN) tumors, whereas frequently lost in high-grade invasive carcinomas, and that (b) loss of DeltaNp63alpha is associated with poor prognosis of invasive bladder urothelial carcinoma patients. However, a functional role of DeltaNp63alpha in progression of urothelial carcinomas remains to be elucidated. Here, we show that loss of DeltaNp63alpha expression promotes invasion of urothelial carcinoma cells. In 5637 cells substantially expressing only DeltaNp63alpha isoform at the protein level, knockdown of endogenous p63 upregulated N-cadherin, which recruited more Src homology and collagen to N-cadherin and activated extracellular signal-regulated kinase (ERK) signaling, and consequently potentiated cell motility, excretion of matrix metalloproteinase-9, and invasion. In T24 cells originally lacking endogenous DeltaNp63alpha expression, exogenous expression of DeltaNp63alpha attenuated invasion by downregulating N-cadherin expression and ERK activity, confirming an invasion-suppressive role of DeltaNp63alpha in urothelial carcinoma cells. We further documented loss of DeltaNp63 expression accompanied by N-cadherin upregulation during muscle-invasive recurrence in patients whose bladder cancer had progressed from LPN tumors to muscle-invasive disease. These results suggest that loss of DeltaNp63alpha and subsequent upregulation of N-cadherin is one of the mechanisms underlying progression of bladder cancer. PMID:19934319

Fukushima, Hiroshi; Koga, Fumitaka; Kawakami, Satoru; Fujii, Yasuhisa; Yoshida, Soichiro; Ratovitski, Edward; Trink, Barry; Kihara, Kazunori

2009-12-15

70

N-cadherin Expression in Breast Cancer: Correlation with an Aggressive Histologic Variant – Invasive Micropapillary Carcinoma  

Microsoft Academic Search

Summary  Upregulation of N-cadherin in epithelial tumor cells has been shown to contribute to the invasive\\/metastatic phenotype. It\\u000a remains however to be determined whether N-cadherin is increased in human breast cancers with enhanced malignant potential.\\u000a We examined a large number of invasive breast cancer specimens (n=114) for N- and E-cadherin. These specimens compared invasive duct carcinomas (IDCs) of varying histologic grades

Chandandeep Nagi; Mitchell Guttman; Shabnam Jaffer; Rui Qiao; Rinat Keren; Aymara Triana; Maomi Li; James Godbold; Ira J. Bleiweiss; Rachel B. Hazan

2005-01-01

71

MMP-7 mediates cleavage of N-cadherin and promotes smooth muscle cell apoptosis  

PubMed Central

Aims Vascular smooth muscle cell (VSMC) apoptosis can lead to thinning of the fibrous cap and plaque instability. We previously showed that cell–cell contacts mediated by N-cadherin reduce VSMC apoptosis. This study aimed to determine whether matrix-degrading metalloproteinase (MMP)-dependent N-cadherin cleavage causes VSMC apoptosis. Methods and results Induction of human VSMC apoptosis using different approaches, including 200 ng/mL Fas ligand (Fas-L) and culture in suspension, caused N-cadherin cleavage and resulted in the appearance of a C-terminal fragment of N-cadherin (?35 kDa). Appearance of this fragment during apoptosis was inhibited by 47% with the broad-spectrum MMP inhibitor BB-94. We observed retarded cleavage of N-cadherin after treatment with Fas-L in aortic mouse VSMCs lacking MMP-7. Furthermore, VSMC apoptosis, measured by quantification of cleaved caspase-3, was 43% lower in MMP-7 knockout mouse VSMCs compared with wild-type VSMCs following treatment with Fas-L. Addition of recombinant active MMP-7 increased the amount of N-cadherin fragment by 82% and augmented apoptosis by 53%. The involvement of MMP-7 was corroborated using human cells, where a MMP-7 selective inhibitor reduced the amount of fragment formed by 51%. Importantly, we observed that treatment with Fas-L increased levels of active MMP-7 by 80%. Finally, we observed significantly increased cleavage of N-cadherin, MMP-7 activity, and apoptosis in human atherosclerotic plaques compared with control arteries, and a significant reduction in apoptosis in atherosclerotic plaques from MMP-7 knockout mice. Conclusion This study demonstrates that MMP-7 is involved in the cleavage of N-cadherin and modulates VSMC apoptosis, and may therefore contribute to plaque development and rupture.

Williams, Helen; Johnson, Jason L.; Jackson, Christopher L.; White, Stephen J.; George, Sarah J.

2010-01-01

72

Intervention effects of ganoderma lucidum spores on epileptiform discharge hippocampal neurons and expression of neurotrophin-4 and N-cadherin.  

PubMed

Epilepsy can cause cerebral transient dysfunctions. Ganoderma lucidum spores (GLS), a traditional Chinese medicinal herb, has shown some antiepileptic effects in our previous studies. This was the first study of the effects of GLS on cultured primary hippocampal neurons, treated with Mg(2+) free medium. This in vitro model of epileptiform discharge hippocampal neurons allowed us to investigate the anti-epileptic effects and mechanism of GLS activity. Primary hippocampal neurons from <1 day old rats were cultured and their morphologies observed under fluorescence microscope. Neurons were confirmed by immunofluorescent staining of neuron specific enolase (NSE). Sterile method for GLS generation was investigated and serial dilutions of GLS were used to test the maximum non-toxic concentration of GLS on hippocampal neurons. The optimized concentration of GLS of 0.122 mg/ml was identified and used for subsequent analysis. Using the in vitro model, hippocampal neurons were divided into 4 groups for subsequent treatment i) control, ii) model (incubated with Mg(2+) free medium for 3 hours), iii) GLS group I (incubated with Mg(2+) free medium containing GLS for 3 hours and replaced with normal medium and incubated for 6 hours) and iv) GLS group II (neurons incubated with Mg(2+) free medium for 3 hours then replaced with a normal medium containing GLS for 6 hours). Neurotrophin-4 and N-Cadherin protein expression were detected using Western blot. The results showed that the number of normal hippocampal neurons increased and the morphologies of hippocampal neurons were well preserved after GLS treatment. Furthermore, the expression of neurotrophin-4 was significantly increased while the expression of N-Cadherin was decreased in the GLS treated group compared with the model group. This data indicates that GLS may protect hippocampal neurons by promoting neurotrophin-4 expression and inhibiting N-Cadherin expression. PMID:23637882

Wang, Shu-Qiu; Li, Xiao-Jie; Zhou, Shaobo; Sun, Di-Xiang; Wang, Hui; Cheng, Peng-Fei; Ma, Xiao-Ru; Liu, Lei; Liu, Jun-Xing; Wang, Fang-Fang; Liang, Yan-Feng; Wu, Jia-Mei

2013-04-24

73

Foxp-mediated suppression of N-cadherin regulates neuroepithelial character and progenitor maintenance in the CNS.  

PubMed

Neuroepithelial attachments at adherens junctions are essential for the self-renewal of neural stem and progenitor cells and the polarized organization of the developing central nervous system. The balance between stem cell maintenance and differentiation depends on the precise assembly and disassembly of these adhesive contacts, but the gene regulatory mechanisms orchestrating this process are not known. Here, we demonstrate that two Forkhead transcription factors, Foxp2 and Foxp4, are progressively expressed upon neural differentiation in the spinal cord. Elevated expression of either Foxp represses the expression of a key component of adherens junctions, N-cadherin, and promotes the detachment of differentiating neurons from the neuroepithelium. Conversely, inactivation of Foxp2 and Foxp4 function in both chick and mouse results in a spectrum of neural tube defects associated with neuroepithelial disorganization and enhanced progenitor maintenance. Together, these data reveal a Foxp-based transcriptional mechanism that regulates the integrity and cytoarchitecture of neuroepithelial progenitors. PMID:22542185

Rousso, David L; Pearson, Caroline Alayne; Gaber, Zachary B; Miquelajauregui, Amaya; Li, Shanru; Portera-Cailliau, Carlos; Morrisey, Edward E; Novitch, Bennett G

2012-04-26

74

N-cadherin regulates primary motor axons growth and branching during zebrafish embryonic development  

PubMed Central

N-cadherin is a classical type I cadherin that contributes to the formation of neural circuits by regulating growth cone migration and the formation of synaptic contacts. This study analyzed the role of N-cadherin in primary motor axons growth during development of the zebrafish (Danio rerio) embryo. After exiting the spinal cord, primary motor axons migrate ventrally through a common pathway and form the first neuromuscular junction with the muscle pioneer cells located at the horizontal myoseptum, which serves as a choice point for cell-type specific pathway selection. Analysis of N-cadherin mutants (cdh2hi3644Tg) and embryos injected with N-cadherin antisense morpholinos showed primary motor axons extending aberrant axonal branches at the choice point in ~40% of the somitic hemisegments, and an ~150% increase in the number of branches per axon length within the ventral myotome. Analysis of individual axons trajectories showed that the caudal (CaP) and rostral (RoP) motor neurons axons formed aberrant branches at the choice point which abnormally extended in the rostrocaudal axis and ventrally to the horizontal myoseptum. Expression of a dominant-interfering N-cadherin cytoplasmic domain in primary motor neurons caused some axons to abnormally stall at the horizontal myoseptum and to impair their migration into the ventral myotome. However, in N-cadherin depleted embryos the majority of primary motor axons innervated their appropriate myotomal territories indicating that N-cadherin regulates motor axon growth and branching without severely affecting the mechanisms that control axonal target selection.

Bruses, Juan L

2013-01-01

75

N-Cadherin and Integrin Blockade Inhibit Arteriolar Myogenic Reactivity but not Pressure-Induced Increases in Intracellular Ca2+  

PubMed Central

The vascular myogenic response is characterized by arterial constriction in response to an increase in intraluminal pressure and dilatation to a decrease in pressure. This mechanism is important for the regulation of blood flow, capillary pressure, and arterial pressure. The identity of the mechanosensory mechanism(s) for this response is incompletely understood but has been shown to include the integrins as cell–extracellular matrix receptors. The possibility that a cell–cell adhesion receptor is involved has not been studied. Thus, we tested the hypothesis that N-cadherin, a cell–cell adhesion molecule in vascular smooth muscle cells (VSMCs), was important for myogenic responsiveness. The purpose of this study was to investigate: (1) whether cadherin inhibition blocks myogenic responses to increases in intraluminal pressure and (2) the effect of the cadherin or integrin blockade on pressure-induced changes in [Ca2+]i. Cadherin blockade was tested in isolated rat cremaster arterioles on myogenic responses to acute pressure steps from 60 to 100?mmHg and changes in VSMC Ca2+ were measured using fura-2. In the presence of a synthetic cadherin inhibitory peptide or a function-blocking antibody, myogenic responses were inhibited. In contrast, during N-cadherin blockade, pressure-induced changes in [Ca2+]i were not altered. Similarly, vessels treated with function-blocking ?1- or ?3-integrin antibodies maintained pressure-induced [Ca2+]i responses despite inhibition of myogenic constriction. Collectively, these data suggest that both cadherins and integrins play a fundamental role in mediating myogenic constriction but argue against their direct involvement in mediating pressure-induced [Ca2+]i increases.

Jackson, Teresa Y.; Sun, Zhe; Martinez-Lemus, Luis A.; Hill, Michael A.; Meininger, Gerald A.

2010-01-01

76

VIP and VIP Gene Silencing Modulation of Differentiation Marker N-Cadherin and Cell Shape of Corneal Endothelium in Human Corneas Ex Vivo  

PubMed Central

Purpose Vasoactive intestinal peptide (VIP) is expressed by corneal endothelial (CE) cells and is present in the aqueous humor, which bathes CE cells in vivo. This study demonstrated the role of CE cell VIP in maintaining the expression level of a CE differentiation marker, N-cadherin, and the hexagonal cell shape. Methods To determine the most effective VIP concentration, bovine corneoscleral explants were treated with 0 (control) and 10?12 to 10?6 M VIP. Paired human corneas (nine donors) from an eye bank were used as control; the other corneas were treated with VIP. To silence endogenous VIP, paired fresh human donor corneas (from seven cadavers) were transduced with VIP shRNA or the control lentiviral particles and then bisected/quartered for quantitative analysis by semiquantitative RT-PCR (for mRNA) and Western blot analysis/immunocytochemistry (for protein), whereas alizarin red S staining revealed CE cell shape. Results VIP concentration dependently increased bovine CE cell N-cadherin mRNA levels, with the maximal effect observed between 10?10 (1.47 ± 0.06-fold; P = 0.002) and 10?8 M VIP (1.48 ± 0.18-fold; P = 0.012). VIP (10?8 M) treatment increased N-cadherin protein levels in bovine and human CE cells to 1.98 ± 0.28-fold (P = 0.005) and 1.17 ± 0.10 (range, 0.91–187)-fold (P = 0.050) of their respective controls. VIP antagonist (SN)VIPhyb diminished the VIP effect. VIP silencing resulted in deterioration of the hexagonal cell shape and decreased levels of VIP protein and mRNA, N-cadherin (but not connexin-43) mRNA and protein, and the antiapoptotic Bcl-2 protein. Conclusions Through its autocrine VIP, CE cells play an active role in maintaining the differentiated state and suppressing apoptosis in the corneal endothelium in situ.

Koh, Shay-Whey M.; Chandrasekara, Krish; Abbondandolo, Cara J.; Coll, Timothy J.; Rutzen, Allan R.

2008-01-01

77

NHERF Links the N-Cadherin\\/Catenin Complex to the Platelet-derived Growth Factor Receptor to Modulate the Actin Cytoskeleton and Regulate Cell Motility  

Microsoft Academic Search

Using phage display, we identified Na\\/H exchanger regulatory factor (NHERF)-2 as a novel binding partner for the cadherin-associated protein, -catenin. We showed that the second of two PSD-95\\/Dlg\\/ZO-1 (PDZ) domains of NHERF interacts with a PDZ-binding motif at the very carboxy terminus of -catenin. N-cadherin expression has been shown to induce motility in a number of cell types. The first

Christopher S. Theisen; James K. Wahl; Keith R. Johnson; Margaret J. Wheelock

2007-01-01

78

Chondroitin sulfate-E fine-tunes osteoblast differentiation via ERK1/2, Smad3 and Smad1/5/8 signaling by binding to N-cadherin and cadherin-11.  

PubMed

Bone formation in the vertebrate skeleton occurs via the processes of endochondral and membranous ossification. Bone matrices contain chondroitin sulfate (CS) chains that regulate endochondral ossification. However, the function of CS in membranous ossification is unclear. Here, using preosteoblastic MC3T3-E1 cells we demonstrate that chondroitin sulfate-E (CS-E) promotes osteoblast differentiation by binding to both N-cadherin and cadherin-11. Differentiated MC3T3-E1 cells exhibited an increase in the total amount of CS and of E-disaccharide units of CS over time. In addition, CS-E polysaccharide, but not CS-A polysaccharide, bound to N-cadherin and cadherin-11 and enhanced osteoblast differentiation. In contrast, osteoblast differentiation was inhibited in chondroitinase ABC-digested MC3T3-E1 cells. Notably, CS-E polysaccharide and hexasaccharide activated intracellular signaling during osteoblast differentiation in non-contacting MC3T3-E1 cells, decreased ERK1/2 phosphorylation, and activated Smad3 and Smad1/5/8; these reactions were blocked by neutralizing antibodies against N-cadherin or cadherin-11, even though cell-cell adhesion is reported to be required for initiation of MC3T3-E1 cell differentiation. Furthermore, CS-E-unit overexpression in MC3T3-E1 cells increased adhesion of the cells to N-cadherin and cadherin-11, and promoted osteoblast differentiation. Collectively, these results suggest that CS-E is a selective ligand for the potential CS receptors, N-cadherin and cadherin-11, leading to osteoblast differentiation of MC3T3-E1 cells. PMID:22440395

Koike, Toshiyasu; Izumikawa, Tomomi; Tamura, Jun-Ichi; Kitagawa, Hiroshi

2012-03-13

79

Activity-Induced Protocadherin Arcadlin Regulates Dendritic Spine Number by Triggering N-Cadherin Endocytosis via TAO2? and p38 MAP Kinases  

PubMed Central

Summary Synaptic activity induces changes in the number of dendritic spines. Here, we report a pathway of regulated endocytosis triggered by arcadlin, a protocadherin induced by electroconvulsive and other excitatory stimuli in hippocampal neurons. The homophilic binding of extracellular arcadlin domains activates TAO2?, a splice variant of the thousand and one amino acid protein kinase 2, cloned here by virtue of its binding to the arcadlin intracellular domain. TAO2? is a MAPKKK that activates the MEK3 MAPKK, which phosphorylates the p38 MAPK. Activation of p38 feeds-back on TAO2?, phosphorylating a key serine required for triggering endocytosis of N-cadherin at the synapse. Arcadlin knockout increases the number of dendritic spines, and the phenotype is rescued by siRNA knockdown of N-cadherin. This pathway of regulated endocytosis of N-cadherin via protocadherin/TAO2?/MEK3/p38 provides a molecular mechanism for transducing neuronal activity into changes in synaptic morphologies.

Yasuda, Shin; Tanaka, Hidekazu; Sugiura, Hiroko; Okamura, Ko; Sakaguchi, Taiki; Tran, Uyen; Takemiya, Takako; Mizoguchi, Akira; Yagita, Yoshiki; Sakurai, Takeshi; De Robertis, E.M.; Yamagata, Kanato

2008-01-01

80

Cell adhesion to agrin presented as a nanopatterned substrate is consistent with an interaction with the extracellular matrix and not transmembrane adhesion molecules  

PubMed Central

Background Molecular spacing is important for cell adhesion in a number of ways, ranging from the ordered arrangement of matrix polymers extracellularly, to steric hindrance of adhesion/signaling complexes intracellularly. This has been demonstrated using nanopatterned RGD peptides, a canonical extracellular matrix ligand for integrin interactions. Cell adhesion was greatly reduced when the RGD-coated nanoparticles were separated by more than 60 nm, indicating a sharp spacing-dependent threshold for this form of cell adhesion. Results Here we show a similar dependence of cell adhesion on the spacing of agrin, a protein that exists as both a secreted, matrix-bound form and a type-2 transmembrane form in vivo. Agrin was presented as a substrate for cell adhesion assays by anchoring recombinant protein to gold nanoparticles that were arrayed at tunable distances onto glass coverslips. Cells adhered well to nanopatterned agrin, and when presented as uniformly coated substrates, adhesion to agrin was comparable to other well-studied adhesion molecules, including N-Cadherin. Adhesion of both mouse primary cortical neurons and rat B35 neuroblastoma cells showed a spacing-dependent threshold, with a sharp drop in adhesion when the space between agrin-coated nanoparticles increased from 60 to 90 nm. In contrast, adhesion to N-Cadherin decreased gradually over the entire range of distances tested (uniform, 30, 60, 90, and 160 nm). The spacing of the agrin nanopattern also influenced cell motility, and peptide competition suggested adhesion was partially integrin dependent. Finally, differences in cell adhesion to C-terminal agrin fragments of different lengths were detected using nanopatterned substrates, and these differences were not evident using uniformly coated substrates. Conclusion These results suggest nanopatterned substrates may provide a physiological presentation of adhesive substrates, and are consistent with cells adhering to agrin through a mechanism that more closely resembles an interaction with the extracellular matrix than a transmembrane adhesion molecule.

Wolfram, Tobias; Spatz, Joachim P; Burgess, Robert W

2008-01-01

81

Distinct Mesenchymal Alterations in N-Cadherin and E-Cadherin Positive Primary Renal Epithelial Cells  

PubMed Central

Background Renal tubular epithelial cells of proximal and distal origin differ markedly in their physiological functions. Therefore, we hypothesized that they also differ in their capacity to undergo epithelial to mesenchymal alterations. Results We used cultures of freshly isolated primary human tubular cells. To distinguish cells of different tubular origin we took advantage of the fact that human proximal epithelial cells uniquely express N-cadherin instead of E-cadherin as major cell-cell adhesion molecule. To provoke mesenchymal alteration we treated these cocultures with TGF-? for up to 6 days. Within this time period, the morphology of distal tubular cells was barely altered. In contrast to tubular cell lines, E-cadherin was not down-regulated by TGF-?, even though TGF-? signal transduction was initiated as demonstrated by nuclear localization of Smad2/3. Analysis of transcription factors and miRNAs possibly involved in E-cadherin regulation revealed high levels of miRNAs of the miR200-family, which may contribute to the stability of E-cadherin expression in human distal tubular epithelial cells. By contrast, proximal tubular epithelial cells altered their phenotype when treated with TGF-?. They became elongated and formed three-dimensional structures. Rho-kinases were identified as modulators of TGF-?-induced morphological alterations. Non-specific inhibition of Rho-kinases resulted in stabilization of the epithelial phenotype, while partial effects were observed upon downregulation of Rho-kinase isoforms ROCK1 and ROCK2. The distinct reactivity of proximal and distal cells was retained when the cells were cultured as polarized cells. Conclusions Interference with Rho-kinase signaling provides a target to counteract TGF-?-mediated mesenchymal alterations of epithelial cells, particularly in proximal tubular epithelial cells. Furthermore, primary distal tubular cells differed from cell lines by their high phenotypic stability which included constant expression of E-cadherin. Our cell culture system of primary epithelial cells is thus suitable to understand and modulate cellular remodeling processes of distinct tubular cells relevant for human renal disease.

Keller, Christof; Kroening, Sven; Zuehlke, Jonathan; Kunath, Frank; Krueger, Bettina; Goppelt-Struebe, Margarete

2012-01-01

82

Soy Protein Adhesive Blends with Synthetic Latex on Wood Veneer  

Microsoft Academic Search

Environmental pollution has prompted an interest in and a need for bio-based wood adhesives. Modified soy protein has shown\\u000a adhesion properties similar to those of formaldehyde based adhesives. The objective of this research was to investigate the\\u000a compatibility of a modified soy protein (MSP) with six commercial synthetic latex adhesives (SLAs). Four different blending\\u000a ratios of MSP and SLAs were

Guangyan Qi; Xiuzhi Susan Sun

2011-01-01

83

Role and significance of focal adhesion proteins in hepatocellular carcinoma.  

PubMed

Focal adhesions are structural links between the extracellular matrix and actin cytoskeleton. They are important sites where dynamic alterations of proteins in the focal contacts are involved during cell movement. Focal adhesions are composed of diverse molecules, for instance, receptors, structural proteins, adaptors, GTPase, kinases and phosphatases. These molecules play critical roles in normal physiological events such as cellular adhesion, movement, cytoskeletal structure and intracellular signaling pathways. In cancers, aberrant expression and altered functions of focal adhesion proteins contribute to adverse tumor behavior. It is evident that these proteins do not function alone, but rather associate and work together in the process of tumor development and cancer metastasis. Focal adhesion proteins have been shown to play critical roles in hepatocellular carcinoma. Understanding the molecular interactions and mechanisms of the interconnected focal adhesion proteins is of particular importance in understanding mechanisms underlying hepatocellular carcinoma progression and development of potential effective treatment. PMID:19368632

Yam, Judy Wai Ping; Tse, Edith Yuk Ting; Ng, Irene Oi-Lin

2009-04-01

84

Mutations in N-cadherin and a Stardust homolog, Nagie oko, affect cell-cycle exit in zebrafish retina.  

PubMed

It has been reported that the loss of apicobasal cell polarity and the disruption of adherens junctions induce hyperplasia in the mouse developing brain. However, it is not fully understood whether hyperplasia is caused by an enhanced cell proliferation, an inhibited neurogenesis, or both. In this study, we found that the ratio of the number of proliferating progenitor cells to the total number of retinal cells increases in the neurogenic stages in zebrafish n-cadherin (ncad) and nagie oko (nok) mutants, in which the apicobasal cell polarity and adherens junctions in the retinal epithelium are disrupted. The cell-cycle progression was not altered in the ncad and nok mutants. Rather, the ratio of the number of cells undergoing neurogenic cell division to the total number of cells undergoing mitosis decreased in the ncad and nok mutant retinas, suggesting that the switching from proliferative cell division to neurogenic cell division was compromised in these mutant retinas. These findings suggest that the inhibition of neurogenesis is a primary defect that causes hyperplasia in the ncad and nok mutant retinas. The Hedgehog-protein kinase A signaling pathway and the Notch signaling pathway regulate retinal neurogenesis in zebrafish. We found that both signaling pathways are involved in the generation of neurogenic defects in the ncad and nok mutant retinas. Taken together, these findings suggest that apicobasal cell polarity and epithelial integrity are essential for retinal neurogenesis in zebrafish. PMID:20362667

Yamaguchi, Masahiro; Imai, Fumiyasu; Tonou-Fujimori, Noriko; Masai, Ichiro

2010-03-31

85

Slit1b-Robo3 signaling and N-cadherin regulate apical process retraction in developing retinal ganglion cells  

PubMed Central

When neurons exit the cell cycle after their terminal mitosis, they detach from the apical surface of the neuroepithelium. Despite the fact that this detachment is crucial for further neurogenesis and neuronal migration, the underlying mechanisms are still not understood. Here, taking advantage of the genetics and imaging possibilities of the zebrafish retina as a model system, we show by knock down experiments that the guidance molecule Slit1b as well as its receptor Robo3 are required for apical retraction of retinal ganglion cells (RGCs). In contrast, N-cadherin seems to be responsible for maintenance of apical attachment as expression of dominant-negative N-cadherin causes RGCs to lose apical attachments prematurely and rescues retraction in slit1b morphants. These results suggest that Slit-Robo signaling downregulates N-cadherin activity to allow apical retraction in newly generated RGCs.

Wong, Grace K W; Baudet, Marie-Laure; Norden, Caren; Leung, Louis; Harris, William A.

2012-01-01

86

Vascular adhesion protein 1 in the eye.  

PubMed

Semicarbazide-sensitive amine oxidase/vascular adhesion protein-1 (SSAO/VAP-1), a dual-function molecule with adhesive and enzymatic properties, is expressed on the surface of vascular endothelial cells of mammals. It also exists as a soluble form (sVAP-1), which is implicated in oxidative stress via its enzymatic activity and can be a prognostic biomarker. Recent evidence suggests that VAP-1 is an important therapeutic target for several inflammation-related ocular diseases, such as uveitis, age-related macular degeneration (AMD), and diabetic retinopathy (DR), by involving in the recruitment of leukocytes at sites of inflammation. Furthermore, VAP-1 plays an important role in the pathogenesis of conjunctival inflammatory diseases such as pyogenic granulomas and the progression of conjunctival lymphoma. VAP-1 may be an alternative therapeutic target in ocular diseases. The in vivo imaging of inflammation using VAP-1 as a target molecule is a novel approach with a potential for early detection and characterization of inflammatory diseases. This paper reviews the critical roles of VAP-1 in ophthalmological diseases which may provide a novel research direction or a potent therapeutic strategy. PMID:23840939

Luo, Wenting; Xie, Fang; Zhang, Zhongyu; Sun, Dawei

2013-06-04

87

Imaging adhesion forces on proteins with the atomic force microscope  

Microsoft Academic Search

We investigated the adhesion forces between single protein molecules and the silicon-nitride tip of an atomic force microscope. Force curves were taken on a sample with single adsorbed proteins while the tip was raster scanned laterally. Out of these force maps we can calculate several images showing for instance the topography or the adhesion force as a function of lateral

Manfred Radmacher; Monika Fritz; Miriam W. Allersma; Christoph F. Schmidt; Paul K. Hansma

1995-01-01

88

Reelin, Rap1 and N-cadherin orient the migration of multipolar neurons in the developing neocortex  

Microsoft Academic Search

Projection neurons migrate from the ventricular zone to the neocortical plate during the development of the mouse brain. Their overall movement is radial, but they become multipolar and move nonradially in the intermediate zone. Here we show that Reelin, the Rap1 GTPase and N-cadherin (NCad) are important for multipolar neurons to polarize their migration toward the cortical plate. Inhibition and

Yves Jossin; Jonathan A Cooper

2011-01-01

89

Cadmium induces N-cadherin cleavage via ERK-mediated ?-secretase activation in C6 astroglia cells.  

PubMed

N-cadherin has known to be involved in tumor progression and metastasis. However, it is still obscure about the signaling pathway involving in the processing of N-cadherin. Thus, we examined which signaling pathway plays a major role in the processing of N-cadherin in C6 glioma cells following treatment of cadmium (Cd), a highly ubiquitous heavy metal. A cleavage product of N-cadherin, N-cad/CTF2 was observed by the treatment of Cd to C6 cells in a time and concentration-dependent manner. The production of N-cad/CTF2 was inhibited by pretreatment of ?-secretase inhibitors or siRNA transfection of nicastrin, indicating that ?-secretase is involved in the cleavage. Interestingly, Cd could activate both ERK and JNK signaling pathways in C6 cells; however, ?-secretase-mediated N-cad/CTF2 production by Cd was completely blocked by MEK1/2 inhibitors PD184352 and U0126, but not by a JNK inhibitor SP600125, demonstrating that the ERK signaling pathway plays a major role in the cleavage. In addition, pretreatment of an antioxidant or Ca(2+) blocker blocked the production of N-cad/CTF2 by Cd together with the inhibition of ERK1/2 phosphorylation. Collectively, these results suggest that Cd increases intracellular Ca(2+) or ROS, which induces ?-secretase-dependent N-cad/CTF2 production via the activation of the ERK signaling pathway in C6 glial cells. PMID:23876460

Jo, Chulman; Koh, Young Ho

2013-07-19

90

Soy protein isolate molecular level contributions to bulk adhesive properties  

NASA Astrophysics Data System (ADS)

Increasing environmental awareness and the recognized health hazards of formaldehyde-based resins has prompted a strong demand for environmentally-responsible adhesives for wood composites. Soy protein-based adhesives have been shown to be commercially viable with 90-day shelf stability and composite physical properties comparable to those of commercial formaldehyde-based particleboards. The main research focus is to isolate and characterize the molecular level features in soy protein isolate responsible for providing mechanical properties, storage stability, and water resistance during adhesive formulation, processing, and wood composite fabrication. Commercial composite board will be reviewed to enhance our understanding of the individual components and processes required for particleboard production. The levels of protein structure will be defined and an overview of current bio-based technology will be presented. In the process, the logic for utilizing soy protein as a sole binder in the adhesive will be reinforced. Variables such as adhesive components, pH, divalent ions, blend aging, protein molecular weight, formulation solids content, and soy protein functionalization will relate the bulk properties of soy protein adhesives to the molecular configuration of the soybean protein. This work has demonstrated that when intermolecular beta-sheet interactions and protein long-range order is disrupted, viscosity and mechanical properties decrease. Storage stability can be maintained through the stabilization of intermolecular beta-sheet interactions. When molecular weight is reduced through enzymatic digestion, long-range order is disrupted and viscosity and mechanical properties decrease accordingly. Processibility and physical properties must be balanced to increase solids while maintaining low viscosity, desirable mechanical properties, and adequate storage stability. The structure of the soybean protein must be related to the particleboard bulk mechanical properties to produce an environmentally responsible, formaldehyde-free adhesive. It is also imperative to study the adhesion between protein and wood.

Shera, Jeanne Norton

91

Vascular adhesion protein-1 (VAP-1)  

Microsoft Academic Search

In 1980s the leukocyte adhesion molecules and their ligands on the vascular endothelium were thought to explain tissue-selective,\\u000a or even tissue-specific, leukocyte traffic. At the same time it became apparent that vessels in inflamed joints displayed\\u000a binding characteristics clearly distinct from those in peripheral lymph nodes, gut and skin. In search of joint-selective\\u000a endothelial adhesion molecules we therefore isolated vascular

Marko Salmi; Sirpa Jalkanen

92

Imaging adhesion forces on proteins with the atomic force microscope  

NASA Astrophysics Data System (ADS)

We investigated the adhesion forces between single protein molecules and the silicon-nitride tip of an atomic force microscope. Force curves were taken on a sample with single adsorbed proteins while the tip was raster scanned laterally. Out of these force maps we can calculate several images showing for instance the topography or the adhesion force as a function of lateral position. Two systems were investigated here: actin adsorbed on mica and tubulin adsorbed on positively charged silanized surfaces, the adhesion force of the tip on the protein was smaller by about a factor of three to five compared to the force measured on the substrate. This is in agreement with previous studies of lysozyme and DNA adsorbed on mica. The data were analyzed by estimating the van der Waals force between the tip and a single protein and between the tip and a flat substrate. The measured adhesion force between the tip and the substrate can be understood by van der Waals. However in the case of the proteins the observed adhesion is larger than expected by only van der Waals forces. So we conclude that there are additional interactions determining the adhesion between the tip and the protein.

Radmacher, Manfred; Fritz, Monika; Allersma, Miriam W.; Schmidt, Christoph F.; Hansma, Paul K.

1995-03-01

93

Up-regulation of gastric cancer cell invasion by Twist is accompanied by N-cadherin and fibronectin expression  

Microsoft Academic Search

Twist, a newly found EMT-inducer, has been reported to be up-regulated in those of diffuse-type gastric carcinomas with high N-cadherin level. We show here MKN45, a cell line derived from undifferentiated carcinomas cells, expresses high levels of Twist. Down-regulation of Twist, using an antisense Twist vector in MKN45 cells, inhibits cell migration and invasion, companied with a morphologic changes associated

Zhou Yang; Xiaohong Zhang; Haiju Gang; Xiaojun Li; Zumao Li; Tao Wang; Juan Han; Ting Luo; Fuqiang Wen; Xiaoting Wu

2007-01-01

94

N-Cadherin expression in motoneurons is directly regulated by androgens: a genetic mosaic analysis in rats  

Microsoft Academic Search

We have recently reported that systemic androgens regulate adult N-cadherin (N-cad) expression in spinal motoneurons. However, the mechanism through which androgen mediates this effect remains undetermined. Androgen may act directly on motoneurons to regulate N-cad expression, or indirectly, via effects on androgen-sensitive afferent or efferent structures. Here, we describe a genetic mosaic investigation of this site-of-action indeterminacy. Following developmental random

Douglas A Monks; Neil V Watson

2001-01-01

95

Optimized Baxter model of protein solutions: electrostatics versus adhesion.  

PubMed

A theory is set up of spherical proteins interacting by screened electrostatics and constant adhesion, in which the effective adhesion parameter is optimized by a variational principle for the free energy. An analytical approach to the second virial coefficient is first outlined by balancing the repulsive electrostatics against part of the bare adhesion. A theory similar in spirit is developed at nonzero concentrations by assuming an appropriate Baxter model as the reference state. The first-order term in a functional expansion of the free energy is set equal to zero which determines the effective adhesion as a function of salt and protein concentrations. The resulting theory is shown to have fairly good predictive power for the ionic-strength dependence of both the second virial coefficient and the osmotic pressure or compressibility of lysozyme up to about 0.2 volume fraction. PMID:15446954

Prinsen, Peter; Odijk, Theo

2004-10-01

96

Activity-dependent regulation of N-cadherin in DRG neurons: Differential regulation of N-cadherin, NCAM, and L1 by distinct patterns of action potentials  

Microsoft Academic Search

than L1 (1 vs. 5 days), and L1 mRNA returned to ABSTRACT: Cell adhesion molecule (CAM) ex- higher levels after terminating the stimulus. The pression is highly regulated during nervous system RSLE splice variant of L1 was not regulated by action development to control cell migration, neurite out-

Kouichi Itoh; Miwako Ozaki; Beth Stevens; R. Douglas Fields

1997-01-01

97

Peroxinectin, a Novel Cell Adhesion Protein from Crayfish Blood  

Microsoft Academic Search

From blood cells of the crayfish Pacifastacus leniusculus a 76-kDa protein that mediated attachment and spreading of the crayfish blood cells was purified. The cDNA for this cell adhesion protein was isolated, cloned, and sequenced. The deduced protein sequence was significantly similar to one family of peroxidases, e.g.,myeloperoxidase. Consistently, the 76-kDa protein, for which we propose the name peroxinectin, had

M. W. Johansson; M. I. Lind; T. Holmblad; P. O. Thornqvist; K. Soderhall

1995-01-01

98

ERM proteins in cell adhesion and membrane dynamics  

Microsoft Academic Search

Ezrin, radixin and moesin, collectively known as the ERM proteins, are a group of closely related membrane–cytoskeleton linkers that regulate cell adhesion and cortical morphogenesis. ERM proteins can self-associate through intra- and inter-molecular interactions, and these interactions mask several binding sites on the proteins. ERM activation involves unfolding of the molecule, and allows the protein to bind to plasma membrane

Paul Mangeat; Christian Roy; Marianne Martin

1999-01-01

99

Collagen I Promotes Metastasis in Pancreatic Cancer by Activating c-Jun NH2Terminal Kinase 1 and Up-regulating N-Cadherin Expression  

Microsoft Academic Search

We have previously shown that N-cadherin expression is associated with tumor invasion, and that some cancer cells respond to specific extracellular matrix molecules by up- regulating N-cadherin. Pancreatic cancer is characterized by excessive deposition of type I collagen. Here, we show that human pancreatic cancer cells respond to collagen I, but not other matrices, by increasing motility and up-regulating mesenchymal

Yasushi Shintani

2006-01-01

100

The Role of the Focal Adhesion Protein PINCH1 for the Radiosensitivity of Adhesion and Suspension Cell Cultures  

Microsoft Academic Search

Focal adhesion (FA) signaling mediated by adhesion to extracellular matrix and growth factor receptors contributes to the regulation of the cellular stress response to external stimuli. Critical to focal adhesion assembly and signaling is the adapter protein PINCH1. To evaluate whether the prosurvival function of PINCH1 in radiation cell survival depends on cell adhesion, we examined PINCH1fl\\/fl and PINCH1?\\/? mouse

Veit Sandfort; Iris Eke; Nils Cordes

2010-01-01

101

N-Cadherin is a prospective cell surface marker of human mesenchymal stem cells that have high ability for cardiomyocyte differentiation.  

PubMed

Mesenchymal stem cells (MSCs) are among the most promising sources of stem cells for regenerative medicine. However, the range of their differentiation ability is very limited. In this study, we explored prospective cell surface markers of human MSCs that readily differentiate into cardiomyocytes. When the cardiomyogenic differentiation potential and the expression of cell surface markers involved in heart development were analyzed using various immortalized human MSC lines, the MSCs with high expression of N-cadherin showed a higher probability of differentiation into beating cardiomyocytes. The differentiated cardiomyocytes expressed terminally differentiated cardiomyocyte-specific markers such as ?-actinin, cardiac troponin T, and connexin-43. A similar correlation was observed with primary human MSCs derived from bone marrow and adipose tissue. Moreover, N-cadherin-positive MSCs isolated with N-cadherin antibody-conjugated magnetic beads showed an apparently higher ability to differentiate into cardiomyocytes than the N-cadherin-negative population. Quantitative polymerase chain reaction analyses demonstrated that the N-cadherin-positive population expressed significantly elevated levels of cardiomyogenic progenitor-specific transcription factors, including Nkx2.5, Hand1, and GATA4 mRNAs. Our results suggest that N-cadherin is a novel prospective cell surface marker of human MSCs that show a better ability for cardiomyocyte differentiation. PMID:23899519

Ishimine, Hisako; Yamakawa, Norio; Sasao, Mari; Tadokoro, Mika; Kami, Daisuke; Komazaki, Shinji; Tokuhara, Makoto; Takada, Hitomi; Ito, Yoshimasa; Kuno, Shinichiro; Yoshimura, Kotaro; Umezawa, Akihiro; Ohgushi, Hajime; Asashima, Makoto; Kurisaki, Akira

2013-07-27

102

Hexavalent chromium at low concentration alters Sertoli cell barrier and connexin 43 gap junction but not claudin-11 and N-cadherin in the rat seminiferous tubule culture model.  

PubMed

Exposure to toxic metals, specifically those belonging to the nonessential group leads to human health defects and among them reprotoxic effects. The mechanisms by which these metals produce their negative effects on spermatogenesis have not been fully elucidated. By using the Durand's validated seminiferous tubule culture model, which mimics the in vivo situation, we recently reported that concentrations of hexavalent chromium, reported in the literature to be closed to that found in the blood circulation of men, increase the number of germ cell cytogenetic abnormalities. Since this metal is also known to affect cellular junctions, we investigated, in the present study, its potential influence on the Sertoli cell barrier and on junctional proteins present at this level such as connexin 43, claudin-11 and N-cadherin. Cultured seminiferous tubules in bicameral chambers expressed the three junctional proteins and ZO-1 for at least 12days. Exposure to low concentrations of chromium (10?g/l) increased the trans-epithelial resistance without major changes of claudin-11 and N-cadherin expressions but strongly delocalized the gap junction protein connexin 43 from the membrane to the cytoplasm of Sertoli cells. The possibility that the hexavalent chromium-induced alteration of connexin 43 indirectly mediates the effect of the toxic metal on the blood-testis barrier dynamic is postulated. PMID:23357549

Carette, Diane; Perrard, Marie-Hélène; Prisant, Nadia; Gilleron, Jérome; Pointis, Georges; Segretain, Dominique; Durand, Philippe

2013-01-26

103

Expression of Focal Adhesion Proteins in the Developing Rat Kidney  

PubMed Central

Focal adhesions play a critical role as centers that transduce signals by cell-matrix interactions and regulate fundamental processes such as proliferation, migration, and differentiation. Focal adhesion kinase (FAK), paxillin, integrin-linked kinase (ILK), and hydrogen peroxide–inducible clone-5 (Hic-5) are major proteins that contribute to these events. In this study, we investigated the expression of focal adhesion proteins in the developing rat kidney. Western blotting analysis revealed that the protein levels of FAK, p-FAK397, paxillin, p-paxillin118, and Hic-5 were high in embryonic kidneys, while ILK expression persisted from the embryonic to the mature stage. Immunohistochemistry revealed that FAK, p-FAK397, paxillin, and p-paxillin118 were strongly expressed in condensed mesenchymal cells and the ureteric bud. They were detected in elongating tubules and immature glomerular cells in the nephrogenic zone. Hic-5 was predominantly expressed in mesenchymal cells as well as immature glomerular endothelial and mesangial cells, suggesting that Hic-5 might be involved in mesenchymal cell development. ILK expression was similar to that of FAK in the developmental stages. Interestingly, ILK was strongly expressed in podocytes in mature glomeruli. ILK might play a role in epithelial cell differentiation as well as kidney growth and morphogenesis. In conclusion, the temporospatially regulated expression of focal adhesion proteins during kidney development might play a role in morphogenesis and cell differentiation.

Matsuura, Sato; Kondo, Shuji; Suga, Kenichi; Kinoshita, Yukiko; Urushihara, Maki; Kagami, Shoji

2011-01-01

104

M protein mediates streptococcal adhesion to HEp-2 cells.  

PubMed Central

Streptococcus pyogenes adheres to human epithelial cells in vitro and in vivo. To identify adhesins, cell wall components were extracted from S. pyogenes M6 with alkali or by treatment with mutanolysin and lysozyme. HEp-2 cells were incubated with extracts of S. pyogenes M6 and then analyzed by Western blot (immunoblot) assays, using antibodies to S. pyogenes. Only one streptococcal component (62 kDa) was bound to HEp-2 cells and was identified serologically as M6 protein. Experiments with pepsin-cleaved fragments of M protein indicated that the binding site was located at the N-terminal half of the molecule. M protein was bound selectively to two trypsin-sensitive surface components, 97 and 205 kDa, of HEp-2 cells on nitrocellulose blots of sodium dodecyl sulfate-polyacrylamide gels. Tritium-labeled lipoteichoic acid bound to different HEp-2 cell components, 34 and 35 kDa, in a parallel experiment, indicating that lipoteichoic acid was not complexed with M protein and does not mediate M-protein binding. The four HEp-2 components were unrelated to fibronectin since they did not react with specific antibodies. An M-protein-deficient (M-) strain of streptococcus (JRS75), grown in chemically defined medium, showed 73% less adhesion activity to HEp-2 monolayers than an M+ strain (JRS4). Streptococcal adhesion was insensitive to competitive inhibition by selected monosaccharides. These results indicate that M protein binds directly to certain HEp-2 cell membrane components and mediates streptococcal adhesion. Images

Wang, J R; Stinson, M W

1994-01-01

105

The MRL proteins: adapting cell adhesion, migration and growth.  

PubMed

MIG-10, RIAM and Lamellipodin (Lpd) are the founding members of the MRL family of multi-adaptor molecules. These proteins have common domain structures but display distinct functions in cell migration and adhesion, signaling, and in cell growth. The binding of RIAM with active Rap1 and with talin provides these MRL molecules with important regulatory roles on integrin-mediated cell adhesion and migration. Furthermore, RIAM and Lpd can regulate actin dynamics through their binding to actin regulatory Ena/VASP proteins. Recent data generated with the Drosophila MRL ortholog called Pico and with RIAM in melanoma cells indicate that these proteins can also regulate cell growth. As MRL proteins represent a relatively new family, many questions on their structure-function relationships remain unanswered, including regulation of their expression, post-translational modifications, new interactions, involvement in signaling and their knockout mice phenotype. PMID:22555291

Coló, Georgina P; Lafuente, Esther M; Teixidó, Joaquin

2012-05-01

106

Vascular adhesion protein-1 blockade suppresses choroidal neovascularization  

PubMed Central

Vascular adhesion protein-1 (VAP-1) is an endothelial cell adhesion molecule involved in leukocyte recruitment. Leukocytes and, in particular, macrophages play an important role in the development of choroidal neovascularization (CNV), an integral component of age-related macular degeneration (AMD). Previously, we showed a role for VAP-1 in ocular inflammation. Here, we investigate the expression of VAP-1 in the choroid and its role in CNV development. VAP-1 was expressed in the choroid, exclusively in the vessels, and colocalized in the vessels of the CNV lesions. VAP-1 blockade with a novel and specific inhibitor significantly decreased CNV size, fluorescent angiographic leakage, and the accumulation of macrophages in the CNV lesions. Furthermore, VAP-1 blockade significantly reduced the expression of inflammation-associated molecules such as tumor necrosis factor (TNF) -?, monocyte chemoattractant protein (MCP) -1, and intercellular adhesion molecule (ICAM) -1. This work provides evidence for an important role of VAP-1 in the recruitment of macrophages to CNV lesions, establishing a novel link between VAP-1 and angiogenesis. Inhibition of VAP-1 may become a new therapeutic strategy in the treatment of AMD.—Noda, K., She, H., Nakazawa, T., Hisatomi, T., Nakao, S., Almulki, L., Zandi, S., Miyahara, S., Ito, Y., Thomas, K. L., Garland, R. C., Miller, J. W., Gragoudas, E. S., Mashima, Y., Hafezi-Moghadam, A. Vascular adhesion protein-1 blockade suppresses choroidal neovascularization.

Noda, Kousuke; She, Haicheng; Nakazawa, Toru; Hisatomi, Toshio; Nakao, Shintaro; Almulki, Lama; Zandi, Souska; Miyahara, Shinsuke; Ito, Yasuhiro; Thomas, Kennard L.; Garland, Rebecca C.; Miller, Joan W.; Gragoudas, Evangelos S.; Mashima, Yukihiko; Hafezi-Moghadam, Ali

2008-01-01

107

N-Cadherin Expression Is Associated with Acquisition of EMT Phenotype and with Enhanced Invasion in Erlotinib-Resistant Lung Cancer Cell Lines  

PubMed Central

Background The epidermal growth-factor receptor tyrosine kinase inhibitors have been effective in non-small cell lung cancer patients. However, acquired resistance eventually develops in most patients despite an initial positive response. Emerging evidence suggests that there is a molecular connection between acquired resistance and the epithelial–mesenchymal transition (EMT). N-cadherin is involved in the EMT and in the metastasis of cancer cells. Here, we analyzed N-cadherin expression and function in erlotinib-resistant lung cancer cell lines. Methods H1650 cell lines were used to establish the subline resistant to erlotinib(H1650ER). Then, induction of the EMT was analyzed using immunostaining and western blots in H1650ER cells. N-cadherin expression in the resistant cells was examined using FACS and western blot. In addition, an invasion assay was performed to characterize the resistant cells. The effects of N-cadherin on cell proliferation and invasion were analyzed. The association of N-cadherin expression with the EMT phenotype was investigated using immunohistochemical analysis of 13 archived, lung adenocarcinoma tissues, before and after treatment with erlotinib. Results In H1650ER cells, N-cadherin expression was upregulated, paralleled by the reduced expression of E-cadherin. The marked histological change and the development of a spindle-like morphology suggest that H1650ER cells underwent an EMT, accompanied by a decrease in E-cadherin and an increase in vimentin. A change in the EMT status between pre-and post-treatment was observed in 11 out of 13 cases (79%). In biopsies of resistant cancers, N-cadherin expression was increased in 10 out of 13 cases. Induction of the EMT was consistent with aggressive characteristics. Inhibition of N-cadherin expression by siRNA was tested to reduce proliferation and invasion of H1650ER cells in vitro. Conclusions Our data provide evidence that induction of the EMT contributes to the acquired resistance to EGFR-TKIs in lung cancer. It suggests that N-cadherin is a potential molecular target in the treatment of NSCLC.

Zhang, Xiaoju; Liu, Guangzhi; Kang, Yi; Dong, Zhaogang; Qian, Qiyu; Ma, Xitao

2013-01-01

108

Protein Adsorption and Subsequent Fibroblasts Adhesion on Hydroxyapatite Nanocrystals  

NASA Astrophysics Data System (ADS)

Quartz crystal microbalance with dissipation (QCM-D) technique was employed for protein adsorption and subsequent fibroblast adhesion on hydroxyapatite (HAp) nanocrystals. The pre-adsorption of three proteins (albumin (BSA) or fibronectin (Fn) or collagen (Col)) and subsequent adsorption of fetal bovine serum (FBS), and the adhesion of fibroblasts on the surface were in situ monitored, and evaluated with the frequency shift (?f) and dissipation energy shift (?D), and the viscoelastic change as ?D-?f plot. The Col adsorption showed larger ?f and ?D values compared with BSA or Fn adsorption, and the subsequent FBS adsorption depended on the pre-adsorbed proteins. The ?D-?f plot of the cell adhesion also showed the different behaviour on the surfaces, indicating the process affected by cell-protein interactions. The confocal laser scanning microscope images of adherent cells showed the different morphology and pseudopod on the surfaces. The cells adhered on the surfaces modified with Fn and Col had the uniaxially expanded shape with fibrous pseudopods, while those modified with BSA had round shape. The different cell-protein interaction would cause the arrangement of extracellular matrix and cytoskeleton changes at the interfaces.

Tagaya, Motohiro; Ikoma, Toshiyuki; Takemura, Taro; Hanagata, Nobutaka; Yoshioka, Tomohiko; Tanaka, Junzo

2011-10-01

109

Protein engineering of a fibroblast growth factor-1 fusion protein with cell adhesive activity.  

PubMed

Fibroblast growth factor-1 (FGF1) is one of the most potent angiogenic growth factors, and also plays an important role in regulating cellular functions including cell proliferation, motility, differentiation, survival, and tissue regeneration processes. Here we described a novel fusion protein that was designed by combining the cell adhesion sequence from fibronectin with FGF1. The F1-Fn fusion protein functions as a minimized protein that directs integrin-dependent cell adhesion and stimulates cellular responses including cell proliferation and differentiation. Moreover, our results indicate that Fn-mediated signaling synergizes with signals from FGF1 in promoting cellular adhesion, proliferation, and differentiation in MG63 cells. PMID:19779651

Jeon, Eunyi; Kim, Hae-Won; Jang, Jun-Hyeog

2009-10-01

110

A Listeria adhesion protein-deficient Listeria monocytogenes strain shows reduced adhesion primarily to intestinal cell lines  

Microsoft Academic Search

Listeria monocytogenes adheres and penetrates intestinal cell linings for systemic infection. A 104-kDa Listeria adhesion protein (LAP) from L. monocytogenes was previously demonstrated to be responsible for adhesion to intestinal enterocyte-like Caco-2 cells. We investigated the adhesion and invasion characteristics of a LAP-deficient mutant L. monocytogenes strain (A572) to various human intestinal and non-intestinal cell lines to assess the possible

Ziad W. Jaradat; Jennifer L. Wampler; Arun K. Bhunia

2003-01-01

111

Blockade of vascular adhesion protein-1 attenuates choroidal neovascularization  

PubMed Central

Purpose Vascular adhesion protein (VAP)-1 is an adhesion molecule elucidated as a mediator of the leukocyte recruitment cascade. The purpose of this study was to investigate the role of VAP-1 in ocular inflammatory neovascularization using a mouse laser-induced choroidal neovascularization (CNV) model. Methods CNV was induced with 532 nm laser irradiation in C57BL/6 mice, and production of VAP-1 protein in the retinal pigment epithelium (RPE) choroid during CNV formation was examined. CNV animals were treated with the specific VAP-1 inhibitor U-V002 or vehicle solution, and the volume of CNV tissue was evaluated with volumetric measurements. Macrophage infiltration into the CNV lesions was evaluated using two different techniques, flatmount staining and real-time polymerase chain reaction (PCR) for F4/80. The protein levels of intercellular adhesion molecule (ICAM)-1, monocyte chemoattractant protein (MCP)-1, P-selectin, and vascular endothelial growth factor (VEGF) in the RPE-choroid were measured with enzyme-linked immunosorbent assay (ELISA). Results VAP-1 inhibition significantly suppressed CNV formation in a dose-dependent manner and reduced macrophage infiltration into CNV lesions. Furthermore, VAP-1 blockade decreased the expression of ICAM-1 and MCP-1, both of which play a pivotal role in macrophage recruitment. Conclusions Our data suggest VAP-1 has an important role during ocular inflammatory neovascularization through leukocyte recruitment. VAP-1 inhibition may be a novel and potent therapeutic strategy in treating CNV formation.

Yoshikawa, Nami; Ozawa, Yoko; Tsubota, Kazuo; Mashima, Yukihiko; Ishida, Susumu

2012-01-01

112

Progress in demystification of adhesion G protein-coupled receptors.  

PubMed

Adhesion G protein-coupled receptors (aGPCR) form the second largest class of GPCR. They are phylogenetically old and have been highly conserved during evolution. Mutations in representatives of this class are associated with severe diseases such as Usher Syndrome, a combined congenital deaf-blindness, or bifrontal parietal polymicrogyria. The main characteristics of aGPCR are their enormous size and the complexity of their N termini. They contain a highly conserved GPCR proteolytic site (GPS) and several functional domains that have been implicated in cell-cell and cell-matrix interactions. Adhesion GPCR have been proposed to serve a dual function as adhesion molecules and as classical receptors. However, until recently there was no proof that aGPCR indeed couple to G proteins or even function as classical receptors. In this review, we have summarized and discussed recent evidence that aGPCR present many functional features of classical GPCR, including multiple G protein-coupling abilities, G protein-independent signaling and oligomerization, but also specific signaling properties only found in aGPCR. PMID:23518449

Liebscher, Ines; Schöneberg, Torsten; Prömel, Simone

2013-08-01

113

Structural basis of cell-cell adhesion by cadherins  

Microsoft Academic Search

Crystal structures of the amino-terminal domain of N-cadherin provide a picture at the atomic level of a specific adhesive contact between cells. A repeated set of dimer interfaces is common to the structure in three lattices. These interactions combine to form a linear zipper of molecules that mirrors the linear structure of the intracellular filaments with which cadherins associate. This

Lawrence Shapiro; Allison M. Fannon; Peter D. Kwong; Andrew Thompson; Mogens S. Lehmann; Gerhard Grübel; Jean-François Legrand; Jens Als-Nielsen; David R. Colman; Wayne A. Hendrickson

1995-01-01

114

Cloning and expression of cDNA encoding a neural calcium-dependent cell adhesion molecule: its identity in the cadherin gene family  

PubMed Central

The neural cadherin (N-cadherin) is a Ca2+-dependent cell-cell adhesion molecule detected in neural tissues as well as in non-neural tissues. We report here the nucleotide sequence of the chicken N-cadherin cDNA and the deduced amino acid sequence. The sequence data suggest that N- cadherin has one transmembrane domain which divides the molecule into an extracellular and a cytoplasmic domain; the extracellular domain contains internal repeats of characteristic sequences. When the N- cadherin cDNA connected with virus promoters was transfected into L cells which have no endogenous N-cadherin, the transformants acquired the N-cadherin-mediated aggregating property, indicating that the cloned cDNA contained all information necessary for the cell-cell binding action of this molecule. We then compared the primary structure of N-cadherin with that of other molecules defined as cadherin subclasses. The results showed that these molecules contain common amino acid sequences throughout their entire length, which confirms our hypothesis that cadherins make a gene family.

1988-01-01

115

Reelin, Rap1 and N-cadherin orient the migration of multipolar neurons in the developing neocortex.  

PubMed

Projection neurons migrate from the ventricular zone to the neocortical plate during the development of the mouse brain. Their overall movement is radial, but they become multipolar and move nonradially in the intermediate zone. Here we show that Reelin, the Rap1 GTPase and N-cadherin (NCad) are important for multipolar neurons to polarize their migration toward the cortical plate. Inhibition and rescue experiments indicated that Reelin regulates migration through Rap1 and Akt, and that the Rap1-regulated GTPases RalA, RalB, Rac1 and Cdc42 are also involved. We found that Rap1 regulated the plasma membrane localization of NCad and NCad rescued radial polarization when Rap1 was inhibited. However, inhibition of Rap1 or NCad had little effect on glia-dependent locomotion. We propose a multistep mechanism in which Reelin activates Rap1, Rap1 upregulates NCad, and NCad is needed to orient cell migration. PMID:21516100

Jossin, Yves; Cooper, Jonathan A

2011-04-24

116

The Role of the Focal Adhesion Protein PINCH1 for the Radiosensitivity of Adhesion and Suspension Cell Cultures  

PubMed Central

Focal adhesion (FA) signaling mediated by adhesion to extracellular matrix and growth factor receptors contributes to the regulation of the cellular stress response to external stimuli. Critical to focal adhesion assembly and signaling is the adapter protein PINCH1. To evaluate whether the prosurvival function of PINCH1 in radiation cell survival depends on cell adhesion, we examined PINCH1fl/fl and PINCH1?/? mouse embryonic fibroblasts and human cancer cell lines. Here, we found that the enhanced cellular radiosensitivity mediated by PINCH1 depletion observed under adhesion conditions is conserved when cells are irradiated under suspension conditions. This unsuspected finding could not be explained by the observed modification of adhesion and growth factor associated signaling involving FAK, Paxillin, p130CAS, Src, AKT, GSK3? and ERK1/2 under suspension and serum withdrawal relative to adhesion conditions with serum. Our data suggest that the adapter protein PINCH1 critically participates in the regulation of the cellular radiosensitivity of normal and malignant cells similarly under adhesion and suspension conditions.

Sandfort, Veit; Eke, Iris; Cordes, Nils

2010-01-01

117

The role of the focal adhesion protein PINCH1 for the radiosensitivity of adhesion and suspension cell cultures.  

PubMed

Focal adhesion (FA) signaling mediated by adhesion to extracellular matrix and growth factor receptors contributes to the regulation of the cellular stress response to external stimuli. Critical to focal adhesion assembly and signaling is the adapter protein PINCH1. To evaluate whether the prosurvival function of PINCH1 in radiation cell survival depends on cell adhesion, we examined PINCH1(fl/fl) and PINCH1(-/-) mouse embryonic fibroblasts and human cancer cell lines. Here, we found that the enhanced cellular radiosensitivity mediated by PINCH1 depletion observed under adhesion conditions is conserved when cells are irradiated under suspension conditions. This unsuspected finding could not be explained by the observed modification of adhesion and growth factor associated signaling involving FAK, Paxillin, p130(CAS), Src, AKT, GSK3? and ERK1/2 under suspension and serum withdrawal relative to adhesion conditions with serum. Our data suggest that the adapter protein PINCH1 critically participates in the regulation of the cellular radiosensitivity of normal and malignant cells similarly under adhesion and suspension conditions. PMID:20927395

Sandfort, Veit; Eke, Iris; Cordes, Nils

2010-09-28

118

Disruption of CDH2/N-Cadherin-Based Adherens Junctions Leads to Apoptosis of Ependymal Cells and Denudation of Brain Ventricular Walls.  

PubMed

Disruption/denudation of the ependymal lining has been associated with the pathogenesis of various human CNS disorders, including hydrocephalus, spina bifida aperta, and periventricular heterotopia. It has been traditionally considered that ependymal denudation is a consequence of mechanical forces such as ventricular enlargement. New evidence indicates that ependymal disruption can precede ventricular dilation, but the cellular and molecular mechanisms involved in the onset of ependymal denudation are unknown. Here, we present a novel model to study ependymal cell pathophysiology and demonstrate that selective disruption of N-cadherin-based adherens junctions is sufficient to provoke progressive ependymal denudation. Blocking N-cadherin function using specific peptides that interfere with the histidine-alanine-valine extracellular homophilic interaction domain caused early pathologic changes characterized by disruption of zonula adherens and abnormal intracellular accumulation of N-cadherin. These changes then triggered massive apoptosis of ependymal cells and denudation of brain ventricular walls. Because no typical extrinsic mechanical factors such as elevated pressure or stretching forces are involved in this model, the critical role of N-cadherin-based adherens junctions in ependymal survival/physiology is highlighted. Furthermore, the results suggest that abnormal adherens junctions between ependymal cells should be considered as key components of the pathogenesis of CNS disorders associated with ependymal denudation. PMID:23965744

Oliver, Cristian; González, César A; Alvial, Genaro; Flores, Carlos A; Rodríguez, Esteban M; Bátiz, Luis Federico

2013-09-01

119

Small heat shock proteins in cellular adhesion and migration  

PubMed Central

Cellular locomotion and adhesion critically depend on regulated turnover of filamentous actin. Biochemical data from diverse model systems support a role for the family of small heat shock proteins (HSPBs) in microfilament regulation. The small chaperones could either act directly, through competition with the motor myosin, or indirectly, through modulation of actin depolymerizing factor/cofilin activity. However, a direct link between HSPBs and actin-based cellular motility remained to be established. In a recent experimental genetics study, we provided evidence for regulation of Plasmodium motility by HSPB6/Hsp20. The infectious forms of malaria parasites, termed sporozoites, display fast and continuous substrate-dependent motility, which is largely driven by turnover of actin microfilaments. Sporozoite gliding locomotion is essential to avoid destruction by host defense mechanisms and to ultimately reach a hepatocyte, the target cell, where to transform and replicate. Genetic ablation of Plasmodium HSP20 dramatically changed sporozoite speed and substrate adhesion, resulting in impaired natural malaria transmission. In this article, we discuss the function of Hsp20 in this fast-moving unicellular protozoan and implications for the roles of HSPBs in adhesion and migration of eukaryotic cells.

Montagna, Georgina N.; Matuschewski, Kai; Buscaglia, Carlos A.

2012-01-01

120

Protein- and Metal-dependent Interactions of a Prominent Protein in Mussel Adhesive Plaques*  

PubMed Central

The adhesive plaques of Mytilus byssus are investigated increasingly to determine the molecular requirements for wet adhesion. Mfp-2 is the most abundant protein in the plaques, but little is known about its function. Analysis of Mfp-2 films using the surface forces apparatus detected no interaction between films or between a film and bare mica; however, addition of Ca2+ and Fe3+ induced significant reversible bridging (work of adhesion Wad ? 0.3 mJ/m2 to 2.2 mJ/m2) between two films at 0.35 m salinity. The strongest observed Fe3+-mediated bridging approaches the adhesion of oriented avidin-biotin complexes. Raman microscopy of plaque sections supports the co-localization of Mfp-2 and iron, which interact by forming bis- or tris-DOPA-iron complexes. Mfp-2 adhered strongly to Mfp-5, a DOPA-rich interfacial adhesive protein, but not to another interfacial protein, Mfp-3, which may in fact displace Mfp-2 from mica. In the presence of metal ions or Mfp-5, Mfp-2 adhesion was fully reversible. These results suggest that plaque cohesiveness depends on Mfp-2 complexation of metal ions, particularly Fe3+ and also by Mfp-2 interaction with Mfp-5 at the plaque-substratum interface.

Hwang, Dong Soo; Zeng, Hongbo; Masic, Admir; Harrington, Matthew J.; Israelachvili, Jacob N.; Waite, J. Herbert

2010-01-01

121

Expression of Functional Recombinant Mussel Adhesive Protein Mgfp-5 in Escherichia coli  

PubMed Central

Mussel adhesive proteins have been suggested as a basis for environmentally friendly adhesives for use in aqueous conditions and in medicine. However, attempts to produce functional and economical recombinant mussel adhesive proteins (mainly foot protein type 1) in several systems have failed. Here, the cDNA coding for Mytilus galloprovincialis foot protein type 5 (Mgfp-5) was isolated for the first time. Using this cDNA, we produced a recombinant Mgfp-5 fused with a hexahistidine affinity ligand, which was expressed in a soluble form in Escherichia coli and was highly purified using affinity chromatography. The adhesive properties of purified recombinant Mgfp-5 were compared with the commercial extracted mussel adhesive Cell-Tak by investigating adhesion force using atomic force microscopy, material surface coating, and quartz crystal microbalance. Even though further macroscale assays are needed, these microscale assays showed that recombinant Mgfp-5 has significant adhesive ability and may be useful as a bioadhesive in medical or underwater environments.

Hwang, Dong Soo; Yoo, Hyo Jin; Jun, Jong Hyub; Moon, Won Kyu; Cha, Hyung Joon

2004-01-01

122

Adhesion  

NASA Astrophysics Data System (ADS)

Adhesion is a highly practical subject in which the vast majority of published work is either chemical in nature, concerned with chemistry that is thought to occur at an adhesive junction or chemistry of adhesives, or essentially mechanical, concerned with the mechanics of testing and failure of adhesive systems. The role of polymer physics in general and de Gennes' work in particular is to discover what happens at the scale of the polymer chain and hence form a bridge between these two approaches. A distinguishing feature of Gennes' work in adhesion is the way he developed simple models that permitted us to see the essential physics of the situation. This is particularly true in his work in viscoelastic effects on toughness (the de Gennes trumpet) where more sophisticated mechanics had been done but the physical situation was obscure. Much of his work was concerned with the effects of connector molecules in toughening an interface in both elastomeric and glassy materials. This work has been extended by a number of authors and forms the basis of our current understanding of the area.

Brown, Hugh

2008-03-01

123

Molecular mapping of tyrosine-phosphorylated proteins in focal adhesions using fluorescence resonance energy transfer  

Microsoft Academic Search

Microscopy-based fluorescence resonance energy transfer (FRET) provides an opportunity to monitor molecular processes in the natural environment in live cells. Here we studied molecular interactions and tyrosine phosphorylation of paxillin, Crk-associated substrate (CAS), and focal adhesion kinase (FAK) in focal adhesions. For that purpose, these focal adhesion phosphoproteins, fused to cyan or yellow fluorescent proteins (CFP or YFP) were expressed

Christoph Ballestrem; Noam Erez; Joachim Kirchner; Zvi Kam; Alexander Bershadsky; Benjamin Geiger

2006-01-01

124

Adhesion Proteins in the Biology of Breast Cancer: Contribution of CD44  

Microsoft Academic Search

One of the most important features of tumor cell invasion is the ability to establish or modulate adhesion to other cells or to an extracellular matrix, a process mediated by a large number of adhesion proteins. This review examines how CD44 participates in malignant transformation and progression of the breast epithelium. CD44 is a family of cell adhesion glycoproteins generated

A. Herrera-Gayol; S. Jothy

1999-01-01

125

Heterotrimeric G proteins, Focal Adhesion Kinase, and Endothelial Barrier Function  

PubMed Central

Ligands by binding to G protein coupled receptors (GPCRs) stimulate dissociation of heterotrimeric G proteins into G? and G?? subunits. Released G? and G?? subunits induce discrete signaling cues that differentially regulate focal adhesion kinase (FAK) activity and endothelial barrier function. Activation of G proteins downstream of receptors such as protease activated receptor 1 (PAR1) and histamine receptors rapidly increases endothelial permeability which reverses naturally within the following one to two hours. However, activation of G proteins coupled to the sphingosine-1-phosphate receptor 1 (S1P1) signal cues that enhance basal barrier endothelial function and restore endothelial barrier function following the increase in endothelial permeability by edemagenic agents. Intriguingly, both PAR1 and S1P1 activation stimulates FAK activity, which associates with alteration in endothelial barrier function by these agonists. In this review, we focus on the role of the G protein subunits downstream of PAR1 and S1P1 in regulating FAK activity and endothelial barrier function.

Thennes, Tracy; Mehta, Dolly

2011-01-01

126

Expression of epithelial adhesion proteins and integrins in chronic inflammation.  

PubMed Central

Epithelial cell behavior in chronic inflammation is poorly characterized. During inflammation of tooth-supporting structures (periodontal disease), increased proliferation of epithelial cells into the inflamed connective tissue stroma is commonly seen. In some areas ulceration and degeneration take place. We studied alterations in the expression of adhesion molecules and integrins during chronic periodontal inflammation. In inflamed tissue, laminin-1 and type IV collagen were still present in the basement membrane and surrounding blood vessels, but they were also found extravascularly in inflamed connective tissue stroma. Type VII collagen and laminin-5 (also known as kalinin, epiligrin, or nicein) were poorly preserved in the basement membrane zone, but both were found in unusual streak-like distributions in the subepithelial connective tissue stroma in inflamed tissue. Both fibronectin and tenascin were substantially decreased in chronically inflamed connective tissue, showing only punctate staining at the basement membrane zone. Integrins of the beta 1 family showed two distinct staining patterns in epithelial cells during chronic inflammation; focal losses of beta 1 integrins (alpha 2 beta 1 and alpha 3 beta 1) were found in most areas, while in other areas the entire pocket epithelium was found to be strongly positive for beta 1 integrins. No members of the alpha v integrin family were found in any epithelia studied. Expression of the alpha 6 beta 4 integrin was high in basal cells of healthy tissue, but weak in epithelium associated with chronic inflammation. Chronic inflammation therefore involves alterations in both adhesion proteins and integrins expressed by epithelial cells. Basement membrane components found at abnormal sites in stroma in chronic inflammation might serve as new adhesive ligands for various cell types in inflamed stroma. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Haapasalmi, K.; Makela, M.; Oksala, O.; Heino, J.; Yamada, K. M.; Uitto, V. J.; Larjava, H.

1995-01-01

127

Nanostructured composite layers of mussel adhesive protein and ceria nanoparticles.  

PubMed

Mussel adhesive proteins are known for their high affinity to a range of different surfaces, and they therefore appear as ideal candidates for producing thin inorganic-organic composite films with high robustness. In this work we explore the possibility of making cohesive films utilizing layer-by-layer deposition of the highly positively charged mussel adhesive protein, Mefp-1, and negatively charged ceria nanoparticles. This particular material combination was chosen due to recent findings that such films provide good corrosion protection. Quartz crystal microbalance with dissipation monitoring (QCM-D) was used for following the film formation process in situ on silica surfaces. A close to linear growth of the film with number of deposited layers was found for up to 18 deposition steps, the highest number of depositions investigated in this work. The Mefp-1 concentration during film deposition affected the film properties, where a higher protein concentration resulted in a stiffer film. It was also found that the added mass could be amplified by using a Mefp-1 solution containing small aggregates. The surface nanomechanical properties of dried multilayer films were investigated using peak force QNM (quantitative nanomechanical mapping) in air. Homogeneous surface coverage was found under all conditions explored, and the Young's modulus of the outer region of the coating increased when a higher Mefp-1 concentration was used during film deposition. The nature of the outermost surface layer was found to significantly affect the surface nanomechanical properties. The abrasion resistance of the coating was measured by using controlled-force contact mode AFM. PMID:23815752

Krivosheeva, Olga; Sababi, Majid; Dedinaite, Andra; Claesson, Per M

2013-07-18

128

A new crystal form of human vascular adhesion protein 1  

PubMed Central

Human vascular adhesion protein 1 (VAP-1) is involved in lymphocyte–endothelial cell adhesion and has been implicated in many human inflammatory diseases. VAP-1 is a member of the copper amine oxidase family of enzymes with a trihydroxyphenylalanine quinone (TPQ) cofactor. Previously characterized crystals of VAP-1 suffered from anisotropy and contained disordered regions; in addition, one form was consistently twinned. In an effort to grow crystals that diffracted to higher resolution for inhibitor-binding studies, a construct with an N-terminal deletion was made and expressed in the Chinese hamster ovary (CHO) glycosylation mutant cell line Lec8. Screening produced crystals that displayed some anisotropy and contained seven molecules per asymmetric unit. These crystals belonged to space group C2, with unit-cell parameters a = 394.5, b = 115.8, c = 179.3?Å, ? = 112.3°. The structure was refined to a resolution of 2.9?Å, with R cryst and R free values of 0.250 and 0.286, respectively.

Ernberg, Karin; McGrath, Aaron P.; Peat, Thomas S.; Adams, Timothy E.; Xiao, Xiaowen; Pham, Tam; Newman, Janet; McDonald, Ian A.; Collyer, Charles A.; Guss, J. Mitchell

2010-01-01

129

Phosphoinositide-3 Kinase-Rac1-c-Jun NH2-terminal Kinase Signaling Mediates Collagen I-induced Cell Scattering and Up-Regulation of N-Cadherin Expression in Mouse Mammary Epithelial Cells  

PubMed Central

During epithelial-to-mesenchymal transitions (EMTs), cells must change their interactions with one another and with their extracellular matrix in a synchronized manner. To characterize signaling pathways cells use to coordinate these changes, we used NMuMG mammary epithelial cells. We showed that these cells become fibroblastic and scattered, with increased N-cadherin expression when cultured on collagen I. Rac1 and c-Jun NH2-terminal kinase (JNK) were activated when cells were plated on collagen I, and dominant inhibitory Rac1 (RacN17) or inhibition of JNK signaling prevented collagen I–induced morphological changes and N-cadherin up-regulation. Furthermore, inhibiting phosphoinositide-3 kinase (PI3K) activity prevented Rac1 and JNK activation as well as collagen I–induced N-cadherin up-regulation. These data implicate PI3K–Rac1–JNK signaling in collagen I–induced changes in NMuMG cells. To establish a role for N-cadherin in collagen I–induced cell scattering, we generated N-cadherin overexpressing and knockdown NMuMG cells and showed that knocking down N-cadherin expression prevented collagen I–induced morphological changes. Motility assays showed that cells overexpressing N-cadherin were significantly more motile than mock-transfected cells and that N-cadherin-mediated motility was collagen I dependent. In addition, we showed that cord formation and branching in three-dimensional culture (EMT-dependent events) required N-cadherin expression and PI3K–Rac1–JNK signaling.

Shintani, Yasushi; Johnson, Keith R.

2006-01-01

130

Protein-based underwater adhesives and the prospects for their biotechnological production  

Microsoft Academic Search

Biotechnological approaches to practical production of biological protein-based adhesives have had limited success over the\\u000a last several decades. Broader efforts to produce recombinant adhesive proteins may have been limited by early disappointments.\\u000a More recent synthetic polymer approaches have successfully replicated some aspects of natural underwater adhesives. For example,\\u000a synthetic polymers, inspired by mussels, containing the catecholic functional group of 3,4-L-dihydroxyphenylalanine

Russell J. Stewart

2011-01-01

131

Effects of surface wettability and contact time on protein adhesion to biomaterial surfaces  

Microsoft Academic Search

Atomic force microscopy (AFM) was used to directly measure the adhesion forces between three test proteins and low density polyethylene (LDPE) surfaces treated by glow discharge plasma to yield various levels of water wettability. The adhesion of proteins to the LDPE substrates showed a step dependence on the wettability of surfaces as measured by the water contact angle (?). For

Li-Chong Xu; Christopher A. Siedlecki

2007-01-01

132

Regulation of Cellular Adhesion to Extracellular Matrix Proteins by Galectin-3  

Microsoft Academic Search

The control of cellular adhesion to extracellular matrix proteins is poorly understood. In the present analyses, we set out to test the hypothesis that high galectin-3 concentration on the cell surface downregulates cellular adhesion to the extracellular matrix proteins. Various tumor cell lines were briefly incubated without or with galectin-3 and then allowed to adhere to wells coated with laminin-1,

Josiah Ochieng; Maria L. Leite-Browning; Paula Warfield

1998-01-01

133

Electric impedance sensing during the inhibition of cell-cell adhesion  

Microsoft Academic Search

Electric cell impedance sensing (ECIS) was used to monitor the change of in vitro neuron-neuron adhesion in response to the blocking of N-Cam, N-Cadherin and L1. ECIS is a method in which cell morphology and cell mobility can be indirectly measured by changes in intercellular resistance.

R. W. F. Wiertz; W. L. C. Rutten; E. Marani

2008-01-01

134

A Listeria adhesion protein-deficient Listeria monocytogenes strain shows reduced adhesion primarily to intestinal cell lines.  

PubMed

Listeria monocytogenes adheres and penetrates intestinal cell linings for systemic infection. A 104-kDa Listeria adhesion protein (LAP) from L. monocytogenes was previously demonstrated to be responsible for adhesion to intestinal enterocyte-like Caco-2 cells. We investigated the adhesion and invasion characteristics of a LAP-deficient mutant L. monocytogenes strain (A572) to various human intestinal and non-intestinal cell lines to assess the possible target host cells. Among the intestinal cell lines, A572 showed significantly reduced adhesion than the wild type (WT) strain to the cells of ileum-cecum (HCT-8) and colon (Caco-2 and HT-29), whereas A572 and WT did not show any significant differences in adhesion to other intestinal cell lines from duodenum (HuTu-80) or jejunum (Int-407). Differences in adhesion between A572 and WT were little or none in non-intestinal cell lines from liver, kidney, bladder, ovary, cervix, breast, larynx, or skin. Invasion data showed that A572 was invasive but the invasion efficiency was proportional to its adhesion characteristics to respective cell lines. In mouse bioassay, A572 was not found in liver following oral administration, suggesting that LAP mutant was possibly unable to pass through intestinal cell linings. Immuno-electron microscopy revealed that the LAP is localized in the bacterial surface as well as the cytoplasm. In summary, this study indicated that the LAP-mediated adhesion is associated with the intestinal cells originating from the lower part of small intestine and from the upper part of large intestine, and possibly plays an important role during the intestinal phase of infection. PMID:12736821

Jaradat, Ziad W; Wampler, Jennifer W L; Bhunia, Arun W L K

2002-10-19

135

Adhesion to fibronectin's EDbdomain induces tyrosine phosphorylation of focal adhesion proteins in Balb\\/c 3T3 cells  

Microsoft Academic Search

Balb\\/c 3T3 cell adhesion on substrata coated with fibronectin's (FN) alternatively-spliced EDb, implicated in some tumor cell systems, and its neighboring type III repeats (III7 and III8) induced intracellular signaling coincident with morphological responses. These events were analysed using minigene-expressed proteins containing various permutations of type III repeats of FN. Cells adherent to the tri-repeat protein 7-EDb-8 were compared to

Wensheng Chen; Lloyd A. Culp

1998-01-01

136

Aberrant Glycosylation of Plasma Proteins in Severe Preeclampsia Promotes Monocyte Adhesion.  

PubMed

Glycosylation of plasma proteins increases during pregnancy. Our objectives were to investigate an anti-inflammatory role of these proteins in normal pregnancies and determine whether aberrant protein glycosylation promotes monocyte adhesion in preeclampsia. Plasma was prospectively collected from nonpregnant controls and nulliparous patients in all 3 trimesters. Patients were divided into cohorts based on the applicable postpartum diagnosis. U937 monocytes were preconditioned with enzymatically deglycosylated plasma, and monocyte adhesion to endothelial cell monolayers was quantified by spectrophotometry. Plasma from nonpregnant controls, first trimester normotensives, and first trimester patients with mild preeclampsia inhibited monocyte-endothelial cell adhesion (P < .05), but plasma from first trimester patients with severe preeclampsia and second and third trimester normotensives did not. Deglycosylating plasma proteins significantly increased adhesion in all the cohorts. These results support a role of plasma glycoprotein interaction in monocyte-endothelial cell adhesion and could suggest a novel therapeutic target for severe preeclampsia. PMID:23757314

Flood-Nichols, Shannon K; Kazanjian, Avedis A; Tinnemore, Deborah; Gafken, Philip R; Ogata, Yuko; Napolitano, Peter G; Stallings, Jonathan D; Ippolito, Danielle L

2013-06-11

137

Embedded proteins and sacrificial bonds provide the strong adhesive properties of gastroliths  

NASA Astrophysics Data System (ADS)

The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO3. The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude.The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO3. The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30536d

Thormann, Esben; MizunoPresent Address: Nihon L'Oreal, Research; Innovation Center, 3-2-1 Sakado, Takatsu, Kawasaki, Kanagawa, Japan., Hiroyasu; Jansson, Kjell; Hedin, Niklas; Fernández, M. Soledad; Arias, José Luis; Rutland, Mark W.; PaiPresent Address: Center For Functional Nanomaterials, Brookhaven National Laboratory, 735 Brookhaven Avenue, Upton, New York 11973., Ranjith Krishna; Bergström, Lennart

2012-06-01

138

Expression patterns of focal adhesion associated proteins in the developing retina  

Microsoft Academic Search

Adhesive interactions between integrin receptors and the extracellular matrix (ECM) are intimately involved in regulating devel- opment of a variety of tissues within the organism. In the present study, we have investigated the re- lationships between 1 integrin receptors and fo- cal adhesion associated proteins during eye devel- opment. We used specific antibodies to examine the distribution of 1 integrin

Ming Li; Donald S. Sakaguchi

2002-01-01

139

Integrin-associated protein is an adhesion receptor on sickle red blood cells for immobilized thrombospondin  

Microsoft Academic Search

The adhesive protein thrombospondin (TSP) potentially mediates sickle (SS) red blood cell (RBC) adhesion to the blood vessel wall, thereby contributing to vaso-occlusive cri- ses in sickle cell disease. We previously reported that SS RBCs bind to immobilized TSP under flow conditions, whereas normal (AA) red cells do not. However, the SS RBC receptors that mediate this interaction are largely

Julia E. Brittain; Kathryn J. Mlinar; Christopher S. Anderson; Eugene P. Orringer; Leslie V. Parise

2001-01-01

140

Role of surface layer collagen binding protein from indigenous Lactobacillus plantarum 91 in adhesion and its anti-adhesion potential against gut pathogen.  

PubMed

Human feacal isolates were ascertain as genus Lactobacillus using specific primer LbLMA1/R16-1 and further identified as Lactobacillus plantarum with species specific primers Lpl-3/Lpl-2. 25 L. plantarum strains were further assessed for hydrophobicity following the microbial adhesion to hydrocarbons (MATH) method and colonization potentials based on their adherence to immobilized human collagen type-1. Surface proteins were isolated from selected L. plantarum 91(Lp91) strain. The purified collagen binding protein (Cbp) protein was assessed for its anti-adhesion activity against enteric Escherichia coli 0157:H7 pathogen on immobilized collagen. Four L. plantarum strains displayed high degree of hydrophobicity and significant adhesion to collagen. A 72kDa protein was purified which reduced 59.71% adhesion of E. coli 0157:H7 on immobilized collagen as compared to control well during adhesion assay. Cbp protein is the major influencing factor in inhibition of E. coli 0157:H7 adhesion with extracellular matrix (ECM) components. Hydrophobicity and adhesion potential are closely linked attributes precipitating in better colonization potential of the lactobacillus strains. Cbp is substantiated as a crucial surface protein contributing in adhesion of lactobacillus strains. The study can very well be the platform for commercialization of indigenous probiotic strain once their functional attributes are clinically explored. PMID:23890721

Yadav, Ashok Kumar; Tyagi, Ashish; Kaushik, Jai Kumar; Saklani, Asha Chandola; Grover, Sunita; Batish, Virender Kumar

2013-07-26

141

A distinctive role for focal adhesion proteins in three-dimensional cell motility  

PubMed Central

Focal adhesions are large multi-protein assemblies that form at the basal surface of cells on planar dishes, which mediate cell signaling, force transduction, and adhesion to the substratum. While much is known about focal adhesion components in 2-D systems, their role in migrating cells within a more physiological three-dimensional (3-D) matrix is largely unknown. Live-cell microscopy shows that for cells fully embedded in a 3-D matrix, focal adhesion proteins, including vinculin, paxillin, talin, ?-actinin, zyxin, VASP, FAK, and p130Cas, do not form aggregates but are diffusively distributed throughout the cytoplasm. Despite the absence of detectable focal adhesions, focal adhesion proteins still modulate cell motility but in a manner distinct from cells on planar substrates. Rather, focal adhesion proteins in matrix-embedded cells regulate cell speed and persistence by affecting protrusion activity and matrix deformation, two processes that play no direct role in controlling 2-D cell speed. This study shows that membrane protrusions constitute a critical motility/matrix-traction module that drives cell motility in a 3-D matrix.

Fraley, Stephanie I.; Feng, Yunfeng; Krishnamurthy, Ranjini; Kim, Dong-Hwee; Celedon, Alfredo; Longmore, Gregory D.; Wirtz, Denis

2010-01-01

142

Phosphoproteome reveals an atlas of protein signaling networks during osteoblast adhesion.  

PubMed

Cell adhesion on surfaces is a fundamental process in the emerging biomaterials field and developmental events as well. However, the mechanisms regulating this biological process in osteoblasts are not fully understood. Reversible phosphorylation catalyzed by kinases is probably the most important regulatory mechanism in eukaryotes. Therefore, the goal of this study is to assess osteoblast adhesion through a molecular prism under a peptide array technology, revealing essential signaling proteins governing adhesion-related events. First, we showed that there are main morphological changes on osteoblast shape during adhesion up to 3 h. Second, besides classical proteins activated upon integrin activation, our results showed a novel network involving signaling proteins such as Rap1A, PKA, PKC, and GSK3beta during osteoblast adhesion on polystyrene. Third, these proteins were grouped in different signaling cascades including focal adhesion establishment, cytoskeleton rearrangement, and cell-cycle arrest. We have thus provided evidence that a global phosphorylation screening is able to yield a systems-oriented look at osteoblast adhesion, providing new insights for understanding of bone formation and improvement of cell-substratum interactions. Altogether, these statements are necessary means for further intervention and development of new approaches for the progress of tissue engineering. PMID:20127719

Milani, Renato; Ferreira, Carmen V; Granjeiro, José M; Paredes-Gamero, Edgar J; Silva, Rodrigo A; Justo, Giselle Z; Nader, Helena B; Galembeck, Eduardo; Peppelenbosch, Maikel P; Aoyama, Hiroshi; Zambuzzi, Willian F

2010-04-01

143

Regulation of promyogenic signal transduction by cell–cell contact and adhesion  

Microsoft Academic Search

Skeletal myoblast differentiation involves acquisition of the muscle-specific transcriptional program and morphological changes, including fusion into multinucleated myofibers. Differentiation is regulated by extracellular signaling cues, including cell–cell contact and adhesion. Cadherin and Ig adhesion receptors have been implicated in distinct but overlapping stages of myogenesis. N-cadherin signals through the Ig receptor Cdo to activate p38 MAP kinase, while the Ig

Robert S. Krauss

2010-01-01

144

Fast turnover of L1 adhesions in neuronal growth cones involving both surface diffusion and exo/endocytosis of L1 molecules.  

PubMed

We investigated the interplay between surface trafficking and binding dynamics of the immunoglobulin cell adhesion molecule L1 at neuronal growth cones. Primary neurons were transfected with L1 constructs bearing thrombin-cleavable green fluorescent protein (GFP), allowing visualization of newly exocytosed L1 or labeling of membrane L1 molecules by Quantum dots. Intracellular L1-GFP vesicles showed preferential centrifugal motion, whereas surface L1-GFP diffused randomly, revealing two pathways to address L1 to adhesive sites. We triggered L1 adhesions using microspheres coated with L1-Fc protein or anti-L1 antibodies, manipulated by optical tweezers. Microspheres coupled to the actin retrograde flow at the growth cone periphery while recruiting L1-GFP molecules, of which 50% relied on exocytosis. Fluorescence recovery after photobleaching experiments revealed a rapid recycling of L1-GFP molecules at L1-Fc (but not anti-L1) bead contacts, attributed to a high lability of L1-L1 bonds at equilibrium. L1-GFP molecules truncated in the intracellular tail as well as neuronal cell adhesion molecules (NrCAMs) missing the clathrin adaptor binding sequence showed both little internalization and reduced turnover rates, indicating a role of endocytosis in the recycling of mature L1 contacts at the base of the growth cone. Thus, unlike for other molecules such as NrCAM or N-cadherin, diffusion/trapping and exo/endocytosis events cooperate to allow the fast renewal of L1 adhesions. PMID:17538021

Dequidt, Caroline; Danglot, Lydia; Alberts, Philipp; Galli, Thierry; Choquet, Daniel; Thoumine, Olivier

2007-05-30

145

Cell adhesion proteins and alpha-fetoprotein. Similar structural motifs as prerequisites for common functions.  

PubMed

This review summarizes and analyzes data on structural and functional relationships between cell adhesion proteins and alpha-fetoprotein (AFP), which play an important role in embryo- and carcinogenesis and act in synergism with growth factors. These two groups of proteins are mosaic, multimodular, and polyfunctional, and each of their modules can function independently through binding with its specific membrane receptor. Most cell adhesion proteins contain modules similar to epidermal growth factor (EGF) and also their repeats, which determine the involvement of these proteins in regulation of cell proliferation, differentiation, and apoptosis. These EGF-like modules are found to include short motifs similar to the fragment LDSYQCT of human AFP. Both direct and inverted AFP-like motifs are linked through a consensus octapeptide motif CXXGY/FXGX. Such AFP-like motifs of cell adhesion proteins and the tripeptide RGD found in AFP may be structural prerequisites for common functions of these groups of nonhomologous and unrelated proteins. PMID:17922650

Terentiev, A A; Moldogazieva, N T

2007-09-01

146

A comparison of the adsorption of three adhesive proteins to biomaterial surfaces  

Microsoft Academic Search

The adsorption of three cell adhesive proteins with known thrombogenic activity [fibrinogen (FGN), fibronectin (FN), and vitronectin (VN)] was quantified from mono-component protein solutions, from a quaternary-component protein solution, and from plasma and diluted plasma in order to compare their potential for adsorption to polymeric substrates from solutions of varying complexity. The surfaces studied included polyethylene (PE), silicone rubber (SR),

D. J. Fabrizius-Homan; S. L. Cooper

1992-01-01

147

Cloning and Expression of Recombinant Adhesive Protein MEEP-2 of the Blue Mussel, Mytilus Edulis.  

National Technical Information Service (NTIS)

The present invention includes a Mytilus edulis cDNA having a nucleotide sequence that encodes for the Mytilus edulis foot protein-2 (Mefp-2), an example of a mollusk foot protein. Mefp-2 is an integral component of the blue mussels' adhesive protein comp...

F. F. Roberto H. G. Silverman

2004-01-01

148

Adhesion of Mussel Foot Protein Mefp-5 to Mica: An Underwater Superglue†  

PubMed Central

Mussels have a remarkable ability to attach their holdfast, or byssus, opportunistically to a variety of substrata that are wet, saline, corroded, and/or fouled by biofilms. Mytilus edulis foot protein-5 (Mefp-5) is one of several proteins in the byssal adhesive plaque of the mussel M. edulis. The high content of 3,4 dihydroxyphenylalanine (Dopa) (~30 mol%) and its localization near the plaque-substrate interface have often prompted speculation that Mefp-5 plays a key role in adhesion. Using the surface forces apparatus, we show that on mica surfaces Mefp-5 achieves an adhesion energy approaching Ead = ~? 14 mJ/m2. This exceeds the adhesion energy of another interfacial protein, Mefp-3, by a factor of 4–5 and is greater than the adhesion between highly oriented monolayers of biotin and streptavidin. The adhesion to mica is notable for its dependence on Dopa, which is most stable under reducing conditions and acidic pH. Mefp-5 also exhibits strong protein-protein interactions with itself as well as with Mefp-3 from M. edulis.

Danner, Eric W.; Kan, Yajing; Hammer, Malte U.; Israelachvili, Jacob N.; Waite, J. Herbert

2012-01-01

149

Adhesion of mussel foot protein Mefp-5 to mica: an underwater superglue.  

PubMed

Mussels have a remarkable ability to attach their holdfast, or byssus, opportunistically to a variety of substrata that are wet, saline, corroded, and/or fouled by biofilms. Mytilus edulis foot protein-5 (Mefp-5) is one of several proteins in the byssal adhesive plaque of the mussel M. edulis. The high content of 3,4-dihydroxyphenylalanine (Dopa) (~30 mol %) and its localization near the plaque-substrate interface have often prompted speculation that Mefp-5 plays a key role in adhesion. Using the surface forces apparatus, we show that on mica surfaces Mefp-5 achieves an adhesion energy approaching E(ad) = ~-14 mJ/m(2). This exceeds the adhesion energy of another interfacial protein, Mefp-3, by a factor of 4-5 and is greater than the adhesion between highly oriented monolayers of biotin and streptavidin. The adhesion to mica is notable for its dependence on Dopa, which is most stable under reducing conditions and acidic pH. Mefp-5 also exhibits strong protein-protein interactions with itself as well as with Mefp-3 from M. edulis. PMID:22873939

Danner, Eric W; Kan, Yajing; Hammer, Malte U; Israelachvili, Jacob N; Waite, J Herbert

2012-08-08

150

Effect of adhesion proteins and surface chemistry on the procoagulant state of adherent platelets  

NASA Astrophysics Data System (ADS)

Poor hemocompatibility of a blood contacting device can lead to blood clotting, reduced blood flow, and depletion of platelets from the blood. Improved understanding of the processes by which blood-material contact leads to these responses could result in more hemocompatible materials. Platelets accelerate blood clotting by adhesion, aggregation, secretion of proteins and agonists and acceleration of thrombin generation. Platelets are said to be "procoagulant" after phosphatidylserine residues flip from the cytosolic to the extracellular face of the lipid bilayer. This then allows for the assembly of the prothrombinase complex (Xa, Va and calcium) on the platelet membrane, which can rapidly convert prothrombin to thrombin. In this study, three different methods confirmed that adhesion causes platelets to become procoagulant: shortening of clotting times of recalcified plasma, binding of FITC-annexin V, and generation of thrombin in the presence of Va, Xa and prothrombin by adherent platelets. Adherent platelets were 10--23 times more activated than bulk phase unactivated platelets and 10--24 times less activated than bulk phase platelets activated by calcium ionophore. The role of adsorbed fibrinogen, vWF, mixtures of fibrinogen and vWF, fibronectin, whole and dilute plasma, and plasma deficient in adhesion proteins in stimulating platelet procoagulant activity was investigated. The results of these experiments suggested that adhesion proteins affect procoagulant activation to varying degrees and that surfaces preadsorbed with mixtures of adhesion proteins are more activating that surfaces preadsorbed with single adhesion proteins. The hypothesis that materials that affect tightness of binding of adsorbed adhesion proteins affect platelet procoagulant activity was investigated. These studies showed that increasing fluorine content of RFGD polymerized films caused reduced platelet adhesion, but increased procoagulant activity, possibly due to their ability to adsorb greater amounts of vWF.

Grunkemeier, John Mark

151

The Pseudomonas aeruginosa Flagellar Cap Protein, FliD, Is Responsible for Mucin Adhesion  

Microsoft Academic Search

Mucin-specific adhesion of Pseudomonas aeruginosa plays an important role in the initial colonization of this organism in the airways of cystic fibrosis patients. We report here that the flagellar cap protein, FliD, parti- cipates in this adhesion process. A polar chromosomal insertional mutation in the P. aeruginosa fliD gene made this organism nonadhesive to mucin in an in vitro mucin

SHIWANI K. ARORA; BRUCE W. RITCHINGS; ERNESTO C. ALMIRA; STEPHEN LORY; REUBEN RAMPHAL

152

Expression of Adhesion Molecules and G Proteins in Circulating Neutrophils in Chronic Obstructive Pulmonary Disease  

Microsoft Academic Search

We investigated the expression of adhesion molecules in circulating neutrophils (lymphocyte func- tion-associated antigen-1 (LFA-1), Mac-1, and L-selectin) and endothelial cells (soluble intercellular adhesion molecule-1(sICAM-1)) in 23 patients with stable chronic obstructive pulmonary disease (COPD), 18 subjects with exacerbated COPD, and 23 healthy volunteers. Also, in these circulating neutrophils, we assessed the expression of two G protein subunits (G a

AINA NOGUERA; XAVIER BUSQUETS; JAUME SAULEDA; JOSE M. VILLAVERDE; ALVAR G. N. AGUSTÍ; Carmen Santos

1998-01-01

153

Development and characterization of adhesives from soy protein for bonding wood  

Microsoft Academic Search

At present, the production of wood composites mainly relies on the petrochemical-based and formaldehyde-based adhesives such as phenol–formaldehyde (PF) resins and urea–formaldehyde (UF) resins. Formaldehyde is a human carcinogen and petrochemicals are not renewable. In this paper, we describe the development and characterization of a new, environmentally friendly adhesive derived from abundant and renewable soy protein and used to bond

Yuan Liu; Kaichang Li

2007-01-01

154

Two Cell Adhesion Molecules, Nectin and Cadherin, Interact through Their Cytoplasmic Domain-Associated Proteins  

Microsoft Academic Search

We have found a new cell-cell adhesion sys- tem at cadherin-based cell-cell adherens junctions (AJs) consisting of at least nectin and l-afadin. Nectin is a Ca 2 1 -independent homophilic immunoglobulin-like adhesion molecule, and l-afadin is an actin filament- binding protein that connects the cytoplasmic region of nectin to the actin cytoskeleton. Both the trans-interac- tion of nectin and the

Kouichi Tachibana; Hiroyuki Nakanishi; Kenji Mandai; Kumi Ozaki; Wataru Ikeda; Yasunori Yamamoto; Akira Nagafuchi; Shoichiro Tsukita; Yoshimi Takai

2000-01-01

155

Listeria adhesion protein mediated Listeria monocytogenes translocation and infection in cell culture model  

Microsoft Academic Search

Listeria adhesion protein (LAP), an alcohol acetaldehyde dehydrogenase (lmo1634) in Listeria monocytogenes, has dual function: enzymatic activity, and adhesion capacity. Recently, our lab reported that LAP is involved in transepithelial translocation of L. monocytogenes through a paracellular route in Caco-2 cell model. In addition, LAP secretion is facilitated by SecA2 and secreted LAP is re-associated on bacterial cell wall to

Hyochin Kim

2011-01-01

156

Expression profile of the entire family of Adhesion G protein-coupled receptors in mouse and rat  

Microsoft Academic Search

BACKGROUND: The Adhesion G protein-coupled receptors (GPCRs) are membrane-bound receptors with long N termini. This family has 33 members in humans. Several Adhesion GPCRs are known to have important physiological functions in CNS development and immune system response mediated by large cell surface ligands. However, the majority of Adhesion GPCRs are still poorly studied orphans with unknown functions. RESULTS: In

Tatjana Haitina; Fredrik Olsson; Olga Stephansson; Johan Alsiö; Erika Roman; Ted Ebendal; Helgi B Schiöth; Robert Fredriksson

2008-01-01

157

Adhesive Performance of Sorghum Protein Extracted from Sorghum DDGS and Flour  

Microsoft Academic Search

Distillers dried grains with solubles (DDGS) is the main co-product from grain-based ethanol production. The objective of\\u000a this research was to compare the adhesive performance of three types of sorghum proteins: acetic acid-extracted sorghum protein\\u000a from DDGS (PI), aqueous ethanol-extracted sorghum protein from DDGS (PII) and acetic acid-extracted sorghum protein from sorghum\\u000a flour (PF). Physicochemical properties including amino acid composition,

Ningbo Li; Ying Wang; Michael Tilley; Scott R. Bean; Xiaorong Wu; Xiuzhi Susan Sun; Donghai Wang

158

Circulating IgSF proteins inhibit adhesion of antibody targeted microspheres to endothelial inflammatory ligands.  

PubMed

Proposed methods for detecting circulatory system disease include targeting ultrasound contrast agents to inflammatory markers on vascular endothelial cells. For antibody-based therapies, soluble forms of the targeted adhesion proteins of the immunoglobulin superfamily (IgSF) reduce adhesion yet were left unaccounted in prior reports. Microspheres labeled simply with a maximum level of antibodies can reduce the diagnostic sensitivity by adhering to proteins expressed normally at a low level, while sparsely coated particles may be rendered ineffective by circulating soluble forms of the targeted proteins. A new microdevice technique is applied to simultaneously measure the adhesion profile to a series of IgSF-protein-coated surfaces. In this investigation, we quantify the in vitro binding characteristics of 5-microm microspheres to oriented intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) protein-coated surfaces in the presence of human serum at physiological concentrations. Defined regions of a slide were coated with recombinant chimeric Fc-human ICAM-1 and VCAM-1 in variable ratios but constant total concentration. Monoclonal human anti-ICAM-1 or anti-VCAM-1 antibodies in competition with non-binding mouse anti-rabbit antibodies coat the microsphere surface at a constant surface density with variable yet controlled surface activities. Using multiple slide surface IgSF protein and microsphere antibody concentrations, an adhesion profile was developed for the microspheres with and without IgSF proteins from human serum, which demonstrated that exposure to serum reduced microsphere binding, on average, more than 50% compared to the no-serum condition.. The serum effects were limited to antibodies on the microsphere, since binding inhibition was reversed after rinsing serum from the system and fresh antibody-coated microspheres were introduced. This analysis quantifies the binding effects of soluble IgSF proteins from human serum on antibody-based targeted ultrasound detection and drug delivery methods. PMID:19140030

Kerby, Matthew B; Urban, Jane C; Mouallem, Lea; Tripathi, Anubhav

2009-01-13

159

Adhesion dynamics of porcine esophageal fibroblasts on extracellular matrix protein-functionalized poly(lactic acid)  

Microsoft Academic Search

Effective attachment of esophageal cells on biomaterials is one important requirement in designing engineered esophagus substitute for esophageal cancer treatment. In this study, poly(lactic acid) (PLA) was subjected to surface modification by coupling extracellular matrix (ECM) proteins on its surface to promote cell adhesion. Two typical ECM proteins, collagen type I (COL) and fibronectin (FN), were immobilized on the PLA

Ning Cai; Yingxue Gong; Kerm Sin Chian; Vincent Chan; Kin Liao

2008-01-01

160

Cloning and Expression of Recombinant Adhesive Protein MEFP-1 of the Blue Mussel, Mytilus Edulis.  

National Technical Information Service (NTIS)

The present invention comprises a Mytilus edulis cDNA sequence having a nucleotide sequence that encodes for the Mytilus edulis foot protein-1 (Mefp-1), an example of a mollusk foot protein. Mefp-1 is an integral component of the blue mussels' adhesive pr...

F. F. Roberto H. G. Silverman

2004-01-01

161

The differential expression of N-cadherin and E-cadherin distinguishes pleural mesotheliomas from lung adenocarcinomas  

Microsoft Academic Search

Malignant mesotheliomas are highly aggressive tumors that develop most frequently in the pleura of patients chronically exposed to asbestos. The distinction between malignant mesotheliomas and tumors of epithelial origin, particularly peripheral lung adenocarcinoma, can be difficult despite the use of immunocytochemical markers and other diagnostic tools. During embryonic development the cadherin cell-cell adhesion molecules participate in the segregation of cells

A Peralta Soler; K. A Knudsen; M-C Jaurand; K. R Johnson; M. J Wheelock; A. J. P Klein-szanto; H Salazar

1995-01-01

162

Molecular mapping of tyrosine-phosphorylated proteins in focal adhesions using fluorescence resonance energy transfer.  

PubMed

Microscopy-based fluorescence resonance energy transfer (FRET) provides an opportunity to monitor molecular processes in the natural environment in live cells. Here we studied molecular interactions and tyrosine phosphorylation of paxillin, Crk-associated substrate (CAS), and focal adhesion kinase (FAK) in focal adhesions. For that purpose, these focal adhesion phosphoproteins, fused to cyan or yellow fluorescent proteins (CFP or YFP) were expressed in cultured fibroblasts. To assess the dynamics of tyrosine phosphorylation we used YFP- or CFP-tagged SH2 domain of pp60(src) (dSH2), which specifically binds to phosphotyrosine residues. FRET measurements, combined with immunolabeling with phosphospecific antibodies revealed that FAK, CAS and paxillin are tyrosine phosphorylated in early matrix adhesions and that FAK is in FRET proximity to CAS and paxillin in focal complexes and focal adhesions. Data suggest that paxillin incorporation into nascent focal complexes precedes its tyrosine phosphorylation, which then gradually increases. In cells treated with Rho-kinase inhibitors or expressing constitutively active Rac, focal complexes showed similar levels of paxillin tyrosine phosphorylation as seen in mature focal adhesions. Dynamic FRET-based examination indicated that paxillin phosphorylation occurs in specific areas (hotspots) within focal adhesions, whereas FAK phosphorylation is broadly distributed. PMID:16478788

Ballestrem, Christoph; Erez, Noam; Kirchner, Joachim; Kam, Zvi; Bershadsky, Alexander; Geiger, Benjamin

2006-02-14

163

Staphylococcus aureus and Staphylococcus epidermidis adhesion to nanohydroxyapatite in the presence of model proteins.  

PubMed

Bacterial infections can have adverse effects on the efficacy, lifetime, and safety of an implanted device. The aim of this study was to investigate the initial adhesion of several strains, namely S. aureus and S. epidermidis, on two distinct types of nanohydroxyapatite (nanoHA), sintered at 725 °C and 1000 °C. A comparison was also made with nanohydroxyapatite having adsorbed fetal bovine serum (FBS), human fibronectin (FN) and human serum albumin (HSA). Adhered bacterial cells were examined by scanning electron microscopy and quantified as colony forming units after being released by sonication. The wettability of the sample surface with and without adsorbed protein was assessed by contact-angle measurements. NanoHA sintered at 1000 °C showed lower bacterial adhesion than this heat-treated at 725 °C. Adsorption of FBS onto the nanoHA surface caused a decrease in the adhesion of all strains on both materials. The bacterial adhesion patterns in the presence of FN were different for both nanoHA substrates; the adherence of the bacterial strains, except for the clinical strain of S. epidermidis, was significantly higher on nanoHA 1000 in comparison to nanoHA 1000 without protein and the bacterial adhesion on the FN-coated nanoHA 725 was lower in comparison to the bare nanoHA 725. The effect of HSA on bacterial adhesion was concentration and bacterial strain dependent. PMID:22652496

Ribeiro, M; Monteiro, F J; Ferraz, M P

2012-06-01

164

Proteomic analysis of ?4?1 integrin adhesion complexes reveals ?-subunit-dependent protein recruitment  

PubMed Central

Integrin adhesion receptors mediate cell–cell and cell–extracellular matrix interactions, which control cell morphology and migration, differentiation, and tissue integrity. Integrins recruit multimolecular adhesion complexes to their cytoplasmic domains, which provide structural and mechanosensitive signaling connections between the extracellular and intracellular milieux. The different functions of specific integrin heterodimers, such as ?4?1 and ?5?1, have been attributed to distinct signal transduction mechanisms that are initiated by selective recruitment of adhesion complex components to integrin cytoplasmic tails. Here, we report the isolation of ligand-induced adhesion complexes associated with wild-type ?4?1 integrin, an activated ?4?1 variant in the absence of the ? cytoplasmic domain (X4C0), and a chimeric ?4?1 variant with ?5 leg and cytoplasmic domains (?4P?5L), and the cataloguing of their proteomes by MS. Using hierarchical clustering and interaction network analyses, we detail the differential recruitment of proteins and highlight enrichment patterns of proteins to distinct adhesion complexes. We identify previously unreported components of integrin adhesion complexes and observe receptor-specific enrichment of molecules with previously reported links to cell migration and cell signaling processes. Furthermore, we demonstrate colocalization of MYO18A with active integrin in migrating cells. These datasets provide a resource for future studies of integrin receptor-specific signaling events.

Byron, Adam; Humphries, Jonathan D; Craig, Sue E; Knight, David; Humphries, Martin J

2012-01-01

165

Evidence that adhesion of electrically permeabilized platelets to collagen is mediated by guanine nucleotide regulatory proteins.  

PubMed Central

Adhesion of electrically permeabilized platelets to collagen was found to be essentially independent of free Ca2+ concentration in the medium. Addition of stable GTP analogues increased the proportion of adhering cells about 5-fold. This effect was inhibited by guanosine 5'-[beta-thio]diphosphate, cytochalasin D or monoclonal antibodies to glycoprotein Ia. In contrast, the protein kinase C inhibitor staurosporine had only a small effect on the GTP-analogue-enhanced adhesion of the permeabilized cells to collagen. These results suggest that a guanine nucleotide regulatory (G)-protein is directly linked to the collagen receptor and is involved in the actin-dependent recruitment of additional collagen receptors.

Daniel, J L; Dangelmaier, C; Smith, J B

1992-01-01

166

Evaluation of corn germ protein as an extender in plywood adhesive  

Microsoft Academic Search

This study was conducted to evaluate the potential of wet-milled corn germ protein as an extender in plywood adhesive. Partially defatted dried corn germ from wet-milling, containing 2.1% (dry basis, db) crude oil and 24.7% (db) crude protein, was ground to 40-mesh particle size to produce the meal. The predominant water- and saline-soluble proteins were extracted from the corn germ

Mila P. Hojilla-Evangelista

2012-01-01

167

Adhesive ability means inhibition activities for lactobacillus against pathogens and S-layer protein plays an important role in adhesion.  

PubMed

Eighty-five strains of lactobacillus were isolated from the pig intestine and identified by sequencing analysis based on 16S rRNA gene, from which five lactobacillus strains with high adhesive ability were selected. The inhibition ability of the five lactobacillus strains with or without S-layer proteins against adherence of Escherichia coli K88 and Salmonella enteritidis 50335 to Caco-2 was evaluated in vitro with Lactobacillus rhamnosus GG strain (LGG) as a positive control. In addition, tolerance of lactobacilli to heat, acid, bile, Zn(2+) and Cu(2+) were assessed. All five selected strains, Lactobacillus salivarius ZJ614 (JN981856), Lactobacillus reuteri ZJ616 (JN981858), L. reuteri ZJ617 (JN981859), L. reuteri ZJ621 (JN981863) and L. reuteri ZJ623 (JN981865), showed inhibition against the two pathogens, E. coli K88 and S. enteritidis 50335. L. reuteri ZJ621 showed higher inhibition ability than the others to S. enteritidis 50335 (P < 0.05). Sodium dodecyl sulfate-Polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicated that all five strains had abundant bands with molecular weight ranging from 34 to 130 KDa as well as had a common band of approximately 42 KDa. After treatment with 5 M LiCl to remove S-layer protein, the inhibition activities of the lactobacilli against pathogens decreased significantly (P < 0.05). The results showed that higher adhesive ability means higher inhibition activity for lactobacillus against pathogen, in which S-layer proteins plays an important role. PMID:23792230

Zhang, Wenming; Wang, Haifeng; Liu, Jianxin; Zhao, Yunhao; Gao, Kan; Zhang, Juan

2013-06-21

168

Preliminary Study on Chicken Feather Protein–Based Wood Adhesives  

Microsoft Academic Search

The objective of this preliminary study was to partially replace phenol in the synthesis of phenol-formaldehyde resin with feather protein. Feather protein–based resins, which contained one part feather protein and two parts phenol, were formulated under the conditions of two feather protein hydrolysis methods (with and without presence of phenol during hydrolysis), two formaldehyde\\/phenol molar ratios (1.8 and 2.0), and

Zehui Jiang; Daochun Qin; Chung-Yun Hse; Monlin Kuo; Zhaohui Luo; Ge Wang; Yan Yu

2008-01-01

169

Epithelial-Stromal Interactions in Human Breast Cancer: Effects on Adhesion, Plasma Membrane Fluidity and Migration Speed and Directness  

PubMed Central

Interactions occurring between malignant cells and the stromal microenvironment heavily influence tumor progression. We investigated whether this cross-talk affects some molecular and functional aspects specifically correlated with the invasive phenotype of breast tumor cells (i.e. adhesion molecule expression, membrane fluidity, migration) by co-culturing mammary cancer cells exhibiting different degrees of metastatic potential (MDA-MB-231>MCF-7) with fibroblasts isolated from breast healthy skin (normal fibroblasts, NFs) or from breast tumor stroma (cancer-associated fibroblasts, CAFs) in 2D or 3D (nodules) cultures. Confocal immunofluorescence analysis of the epithelial adhesion molecule E-cadherin on frozen nodule sections demonstrated that NFs and CAFs, respectively, induced or inhibited its expression in MCF-7 cells. An increase in the mesenchymal adhesion protein N-cadherin was observed in CAFs, but not in NFs, as a result of the interaction with both kinds of cancer cells. CAFs, in turn, promoted N-cadherin up-regulation in MDA-MB-231 cells and its de novo expression in MCF-7 cells. Beyond promotion of “cadherin switching”, another sign of the CAF-triggered epithelial-mesenchymal transition (EMT) was the induction of vimentin expression in MCF-7 cells. Plasma membrane labeling of monolayer cultures with the fluorescent probe Laurdan showed an enhancement of the membrane fluidity in cancer cells co-cultured with NFs or CAFs. An increase in lipid packing density of fibroblast membranes was promoted by MCF-7 cells. Time-lapsed cell tracking analysis of mammary cancer cells co-cultured with NFs or CAFs revealed an enhancement of tumor cell migration velocity, even with a marked increase in the directness induced by CAFs. Our results demonstrate a reciprocal influence of mammary cancer and fibroblasts on various adhesiveness/invasiveness features. Notably, CAFs' ability to promote EMT, reduction of cell adhesion, increase in membrane fluidity, and migration velocity and directness in mammary cancer cells can be viewed as an overall progression- and invasion-promoting effect.

Lama, Gina; Proietti, Gabriella; Colabianchi, Anna; Papi, Massimiliano; Maiorana, Alessandro; De Spirito, Marco; Micera, Alessandra; Balzamino, Omar Bijorn; Di Leone, Alba; Masetti, Riccardo; Sica, Gigliola

2012-01-01

170

Cell Adhesion Molecule Expression in Human Lens Epithelial Cells After Corticosteroid Exposure  

PubMed Central

Aim: The aim of the study was to investigate changes in cell adhesion molecule expression in human lens epithelial cells (HLEC) subjected to glucocorticoids. Methods: Human lens epithelial cells were exposed to different concentrations of dexamethasone for 24 hours. Cell adhesion molecule expression was studied by western blot and immunohistochemistry of vimentin, N-cadherin, E-cadherin, ?-catenin, ?-catenin and ?-catenin. Expression of the glucocorticoid receptor (GR) was also studied. Cell morphology was examined by transmission electron microscopy (TEM). Result: Expression of N-cadherin, ?-catenin, ?-catenin and GR was significantly decreased in dexamethasone exposed cells as compared to unexposed cells. No significant change in ?-catenin was present. Visualization of adhesion molecules, N-cadherin and ?-catenin, by immunohistochemistry showed decreased antigen reactivity in dexamethasone exposed as compared to the unexposed cells. However, no change was seen for ?-catenin and ?-catenin. E-cadherin was not detectable using western blot or immunohistochemistry. TEM showed multilayering of cells, vacuole formation and appearance of electron-dense multivesicular bodies in HLEC exposed to 0, 0.1, 1, 10 and 100 ?M dexamethasone. Conclusion: Glucocorticoids affect several adhesion molecules in lens epithelial cells, something that may contribute to the pathogenesis of posterior subcapsular opacification.

Celojevic, D; Carlsson, T; Johansson, BR; Nannmark, U; Petersen, A

2012-01-01

171

Amyloid precursor protein is an autonomous growth cone adhesion molecule engaged in contact guidance.  

PubMed

Amyloid precursor protein (APP), a transmembrane glycoprotein, is well known for its involvement in the pathogenesis of Alzheimer disease of the aging brain, but its normal function is unclear. APP is a prominent component of the adult as well as the developing brain. It is enriched in axonal growth cones (GCs) and has been implicated in cell adhesion and motility. We tested the hypothesis that APP is an extracellular matrix adhesion molecule in experiments that isolated the function of APP from that of well-established adhesion molecules. To this end we plated wild-type, APP-, or ?1-integrin (Itgb1)- misexpressing mouse hippocampal neurons on matrices of either laminin, recombinant L1, or synthetic peptides binding specifically to Itgb1 s or APP. We measured GC adhesion, initial axonal outgrowth, and substrate preference on alternating matrix stripes and made the following observations: Substrates of APP-binding peptide alone sustain neurite outgrowth; APP dosage controls GC adhesion to laminin and APP-binding peptide as well as axonal outgrowth in Itgb1- independent manner; and APP directs GCs in contact guidance assays. It follows that APP is an independently operating cell adhesion molecule that affects the GC's phenotype on APP-binding matrices including laminin, and that it is likely to affect axon pathfinding in vivo. PMID:23691241

Sosa, Lucas J; Bergman, Jared; Estrada-Bernal, Adriana; Glorioso, Thomas J; Kittelson, John M; Pfenninger, Karl H

2013-05-14

172

Adhesion forces between Staphylococcus epidermidis and surfaces bearing self-assembled monolayers in the presence of model proteins  

Microsoft Academic Search

Self-assembled monolayers (SAMs) are being developed into coatings to reduce microbial biofilm formation on biomaterials. To test anti-adhesion properties, SAMs can be easily constructed on gold, and used to represent a coated biomaterial. However, coatings that prevent bacterial adhesion must also resist protein adsorption. We explored the competitive effects of bacteria and protein for adsorption to SAMs, choosing fetal bovine

Yatao Liu; Joshua Strauss; Terri A. Camesano

2008-01-01

173

Fabrication of a cell-adhesive protein imprinting surface with an artificial cell membrane structure for cell capturing  

Microsoft Academic Search

We proposed a new molecular imprinting procedure based on molecular integration for the purpose of cell capture. We selected the cell-adhesive protein fibronectin (FN) as the imprinting protein for preparing templates and evaluated selective cell adhesion on the FN imprinting substrate. Silica beads with a diameter of 15?m were used as the stamp matrix and FN molecules were adsorbed as

Kyoko Fukazawa; Kazuhiko Ishihara

2009-01-01

174

Protein Kinase C beta Mediates CD40 Ligand-Induced Adhesion of Monocytes to Endothelial Cells.  

PubMed

Accumulating evidence supports the early involvement of monocyte/macrophage recruitment to activated endothelial cells by leukocyte adhesion molecules during atherogenesis. CD40 and its ligand CD40L are highly expressed in vascular endothelial cells, but its impact on monocyte adhesion and the related molecular mechanisms are not fully understood. The present study was designed to evaluate the direct effect of CD40L on monocytic cell adhesion and gain mechanistic insight into the signaling coupling CD40L function to the proinflammatory response. Exposure of cultured human aortic endothelial cells (HAECs) to clinically relevant concentrations of CD40L (20 to 80 ng/mL) dose-dependently increased human monocytic THP-1 cells to adhere to them under static condition. CD40L treatment induced the expression of vascular cell adhesion molecule-1 (VCAM-1) mRNA and protein expression in HAECs. Furthermore, exposure of HAECs to CD40L robustly increased the activation of protein kinase C beta (PKC?) in ECs. A selective inhibitor of PKC? prevented the rise in VCAM-1 and THP-1 cell adhesion to ECs. Moreover, stimulation of ECs to CD40L induced nuclear factor-?B (NF-?B) activation. PKC? inhibition abolished CD40L-induced NF-?B activation, and NF-?B inhibition reduced expression of VCAM-1, each resulting in reduced THP-1 cell adhesion. Our findings provide the evidence that CD40L increases VCAM-1 expression in ECs by activating PKC? and NF-?B, suggesting a novel mechanism for EC activation. Finally, administration of CD40L resulted in PKC? activation, increased VCAM-1 expression and activated monocytes adhesiveness to HAECs, processes attenuated by PKC? inhibitor. Therefore, CD40L may contribute directly to atherogenesis by activating ECs and recruiting monocytes to them. PMID:24039784

Wu, Zeyu; Zhao, Gang; Peng, Lin; Du, Jialin; Wang, Sanming; Huang, Yijie; Ou, Jinrui; Jian, Zhixiang

2013-09-09

175

Regulation of Cell-Cell Adhesion by Rac and Rho Small G Proteins in MDCK Cells  

Microsoft Academic Search

The Rho small G protein family, consisting of the Rho, Rac, and Cdc42 subfamilies, regulates vari- ous cell functions, such as cell shape change, cell motil- ity, and cytokinesis, through reorganization of the actin cytoskeleton. We show here that the Rac and Rho sub- families furthermore regulate cell-cell adhesion. We prepared MDCK cell lines stably expressing each of dominant active

Kenji Takaishi; Takuya Sasaki; Hirokazu Kotani; Hideo Nishioka; Yoshimi Takai

1997-01-01

176

Characterization of multiple adhesive and counteradhesive domains in the extracellular matrix protein cytotactin  

Microsoft Academic Search

The extracellular matrix molecule cytotactin is a multidomain protein that plays a role in cell migra- tion, proliferation, and differentiation during develop- ment. To analyze the structure-function relationships of the different domains of this glycoprotein, we have prepared a series of fusion constructs in bacterial ex- pression vectors. Results obtained using a number of adhesion assays suggest that at least

Anne L. Prieto; Charlotte Andersson-Fisone; Kathryn L. Crossin

1992-01-01

177

Bacterial cellulose modified using recombinant proteins to improve neuronal and mesenchymal cell adhesion.  

PubMed

A wide variety of biomaterials and bioactive molecules have been applied as scaffolds in neuronal tissue engineering. However, creating devices that enhance the regeneration of nervous system injuries is still a challenge, due the difficulty in providing an appropriate environment for cell growth and differentiation and active stimulation of nerve regeneration. In recent years, bacterial cellulose (BC) has emerged as a promising biomaterial for biomedical applications because of its properties such as high crystallinity, an ultrafine fiber network, high tensile strength, and biocompatibility. The small signaling peptides found in the proteins of extracellular matrix are described in the literature as promoters of adhesion and proliferation for several cell lineages on different surfaces. In this work, the peptide IKVAV was fused to a carbohydrate-binding module (CBM3) and used to modify BC surfaces, with the goal of promoting neuronal and mesenchymal stem cell (MSC) adhesion. The recombinant proteins IKVAV-CBM3 and (19)IKVAV-CBM3 were successfully expressed in E. coli, purified through affinity chromatography, and stably adsorbed to the BC membranes. The effect of these recombinant proteins, as well as RGD-CBM3, on cell adhesion was evaluated by MTS colorimetric assay. The results showed that the (19)IKVAV-CBM3 was able to significantly improve the adhesion of both neuronal and mesenchymal cells and had no effect on the other cell lineages tested. The MSC neurotrophin expression in cells grown on BC membranes modified with the recombinant proteins was also analyzed. PMID:22271600

Pértile, Renata; Moreira, Susana; Andrade, Fábia; Domingues, Lucília; Gama, Miguel

2012-01-23

178

Interspecific Variations in Adhesive Protein Sequences of Mytilus edulis, M. galloprovincialis, and M. trossulus  

Microsoft Academic Search

Variation in the adhesive protein gene se- quences of Mytilus edulis, M. galloprovincialis, and M. trossulus collected in Delaware, Kamaishi (Japan), and Alaska, respectively, was analyzed by the polymerase chain reaction (PCR) using two sets of oligonucleotide primers. The first set, Me 13 and Me 14, was designed to amplify the repetitive region. The length of the amplified fragments was

KOJI INOUE; J. HERBERT WAITE; MAKOTO MATSUOKA; SATOSHI ODO; SHIGEAKI HARAYAMA

1995-01-01

179

Pamlin, a Primary Mesenchyme Cell Adhesion Protein, in the Basal Lamina of the Sea Urchin Embryo  

Microsoft Academic Search

Pamlin, a primary mesenchyme cell (PMC) adhesion protein, was isolated from the blastocoel of embryos of the sea urchin Hemicentrotus pulcherrimus. PMCs isolated from mesenchyme blastulae bound exclusively to pamlin. Pamlin is a distinctive extracellular matrix (ECM) component from reported ECM molecules in sea urchin embryos in its motility on SDS-PAGE gels both with and without 2-mercaptoethanol and histological localization.

Hideki Katow

1995-01-01

180

The ADAM gene family: surface proteins with adhesion and protease activity  

Microsoft Academic Search

An ADAM is a transmembrane protein that contains a disintegrin and metalloprotease domain and, therefore, it potentially has both cell adhesion and protease activities. Currently, the ADAM gene family has 29 members, although the function of most ADAM gene products is unknown. We discuss the ADAM gene products with known functions that act in a highly diverse set of biological

Paul Primakoff; Diana G Myles

2000-01-01

181

Activation of focal adhesion kinase enhances the adhesion of Fusarium solani to human corneal epithelial cells via the tyrosine-specific protein kinase signaling pathway  

PubMed Central

Purpose To determine the role of the integrin-FAK signaling pathway triggered by the adherence of F. solani to human corneal epithelial cells (HCECs). Methods After pretreatment with/without genistein, HCECs were incubated with F. solani spores at different times (0–24 h). Cell adhesion assays were performed by optical microscopy. Changes of the ultrastructure were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The expression of F-actin and Paxillin (PAX) were detected by immunofluorescence and western blotting to detect the expression of these key proteins with/without genistein treatment. Results Cell adhesion assays showed that the number of adhered spores began to rise at 6 h after incubation and peaked at 8 h. SEM and TEM showed that the HCECs exhibited a marked morphological alteration induced by the attachment and entry of the spores. The expression of PAX increased, while the expression of F-actin decreased by stimulation with F. solani. The interaction of F. solani with HCECs causes actin rearrangement in HCECs. Genistein strongly inhibited FAK phosphorylation and the activation of the downstream protein (PAX). F. solani-induced enhancement of cell adhesion ability was inhibited along with the inhibition of FAK phosphorylation. Conclusions Our results suggest that the integrin-FAK signaling pathway is involved in the control of F. solani adhesion to HCECs and that the activation of focal adhesion kinase enhances the adhesion of human corneal epithelial cells to F. solani via the tyrosine-specific protein kinase signaling pathway.

Pan, Xiaojing; Wang, Ye; Zhou, Qingjun; Chen, Peng; Xu, Yuanyuan; Chen, Hao

2011-01-01

182

p0071/PKP4, a multifunctional protein coordinating cell adhesion with cytoskeletal organization.  

PubMed

P0071 is a member of a subfamily of armadillo proteins that also comprises p120-catenin (p120ctn), ?-catenin/NPRAP, ARVCF and the more distantly related plakophilins 1-3. These proteins share a conserved central domain consisting of a series of repeated motifs, the armadillo repeats, which is flanked by more diverse amino- and carboxy-terminal domains. P0071 and the related proteins were first described as components of adherens junctions with a function in clustering and stabilizing cadherins, thereby controlling intercellular adhesion. In addition, these proteins show a cytoplasmic and a nuclear localization. Major progress in understanding their cytoplasmic role has been made in recent years. One common theme appears to be the spatiotemporal control of the small GTPases of the Rho family in various cellular contexts, such as cell adhesion and motility, cell division or neurite outgrowth. In this review article, we focus on the functions of the p0071 protein and its closest relatives in regulating cell adhesion and cytoskeletal organization, which are critically involved in the control of cell polarity. Understanding p0071's multiple functions requires assigning specific functions to particular binding partners and subcellular compartments. The identification of several new p0071 interacting proteins has promoted our understanding of the complex functions of this protein. Moreover, an initial analysis of its regulation begins to shed light on how these functions are coordinated in a cellular context. PMID:23640939

Keil, René; Schulz, Jenny; Hatzfeld, Mechthild

2013-08-01

183

Dominant-negative effect on adhesion by myelin Po protein truncated in its cytoplasmic domain  

PubMed Central

The myelin Po protein is believed to hold myelin together via interactions of both its extracellular and cytoplasmic domains. We have already shown that the extracellular domains of Po can interact in a homophilic manner (Filbin, M.T., F.S. Walsh, B.D. Trapp, J.A. Pizzey, and G.I. Tennekoon. 1990. Nature (Lond.). 344:871-872). In addition, we have shown that for this homophilic adhesion to take place, the cytoplasmic domain of Po must be intact and most likely interacting with the cytoskeleton; Po proteins truncated in their cytoplasmic domains are not adhesive (Wong, M.H., and M.T. Filbin, 1994. J. Cell Biol. 126:1089-1097). To determine if the presence of these truncated forms of Po could have an effect on the functioning of the full-length Po, we coexpressed both molecules in CHO cells. The adhesiveness of CHO cells expressing both full-length Po and truncated Po was then compared to cells expressing only full-length Po. In these coexpressors, both the full-length and the truncated Po proteins were glycosylated. They reached the surface of the cell in approximately equal amounts as shown by an ELISA and surface labeling, followed by immunoprecipitation. Furthermore, the amount of full-length Po at the cell surface was equivalent to other cell lines expressing only full-length Po that we had already shown to be adhesive. Therefore, there should be sufficient levels of full-length Po at the surface of these coexpressors to measure adhesion of Po. However, as assessed by an aggregation assay, the coexpressors were not adhesive. By 60 min they had not formed large aggregates and were indistinguishable from the control transfected cells not expressing Po. In contrast, in the same time, the cells expressing only the full-length Po had formed large aggregates. This indicates that the truncated forms of Po have a dominant-negative effect on the adhesiveness of the full-length Po. Furthermore, from cross-linking studies, full-length Po, when expressed alone but not when coexpressed with truncated Po, appears to cluster in the membrane. We suggest that truncated Po exerts its dominant-negative effect by preventing clustering of full-length Po. We also show that colchicine, which disrupts microtubules, prevents adhesion of cells expressing only the full-length Po. This strengthens our suggestion that an interaction of Po with the cytoskeleton, either directly or indirectly, is required for adhesion to take place.

1996-01-01

184

Cell adhesion proteins and ?-fetoprotein. Similar structural motifs as prerequisites for common functions  

Microsoft Academic Search

This review summarizes and analyzes data on structural and functional relationships between cell adhesion proteins and ?-fetoprotein\\u000a (AFP), which play an important role in embryo-and carcinogenesis and act in synergism with growth factors. These two groups\\u000a of proteins are mosaic, multimodular, and polyfunctional, and each of their modules can function independently through binding\\u000a with its specific membrane receptor. Most cell

A. A. Terentiev; N. T. Moldogazieva

2007-01-01

185

Adhesive properties of soy proteins modified by urea and guanidine hydrochloride  

Microsoft Academic Search

An investigation was conducted on the adhesive and water-resistance properties of soy protein isolates that were modified\\u000a by varying solutions of urea (1, 3, 5, and 8 M) or guanidine hydrochloride (GH) (0.5, 1, and 3 M) and applied on walnut, cherry,\\u000a and pine plywoods. Soy proteins modified by 1 and 3 M urea showed greater shear strengths than did

Weining Huang; Xiuzhi Sun

2000-01-01

186

Proteomic analysis of NMDA receptor–adhesion protein signaling complexes  

Microsoft Academic Search

N-methyl-D-aspartate receptors (NMDAR) mediate long-lasting changes in synapse strength via downstream signaling pathways. We report proteomic characterization with mass spectrometry and immunoblotting of NMDAR multiprotein complexes (NRC) isolated from mouse brain. The NRC comprised 77 proteins organized into receptor, adaptor, signaling, cytoskeletal and novel proteins, of which 30 are implicated from binding studies and another 19 participate in NMDAR signaling.

Holger Husi; Malcolm A. Ward; Jyoti S. Choudhary; Walter P. Blackstock; Seth G. N. Grant

2000-01-01

187

Different Roles for Lactococcal Aggregation Factor and Mucin Binding Protein in Adhesion to Gastrointestinal Mucosa  

PubMed Central

Adhesion of bacteria to mucosal surfaces and epithelial cells is one of the key features for the selection of probiotics. In this study, we assessed the adhesion property of Lactococcus lactis subsp. lactis BGKP1 based on its strong autoaggregation phenotype and the presence of the mucin binding protein (MbpL). Genes involved in aggregation (aggL) and possible interaction with mucin (mbpL), present on the same plasmid pKP1, were previously separately cloned in the plasmid pAZIL. In vivo and in vitro experiments revealed potentially different physiological roles of these two proteins in the process of adherence to the intestine during the passage of the strain through the gastrointestinal tract. We correlated the in vitro and in vivo aggregation of the BGKP1-20 carrying plasmid with aggL to binding to the colonic mucus through nonspecific hydrophobic interactions. The expression of AggL on the bacterial cell surface significantly increased the hydrophobicity of the strain. On the other hand, the presence of AggL in the strain reduced its ability to adhere to the ileum. Moreover, MbpL protein showed an affinity to bind gastric type mucin proteins such as MUC5AC. This protein did not contribute to the binding of the strain to the ileal or colonic part of the intestine. Different potential functions of lactococcal AggL and MbpL proteins in the process of adhesion to the gastrointestinal tract are proposed.

Lukic, Jovanka; Strahinic, Ivana; Jovcic, Branko; Filipic, Brankica; Topisirovic, Ljubisa; Kojic, Milan

2012-01-01

188

Cross-linking the protein precursor of marine mussel adhesives: bulk measurements and reagents for curing.  

PubMed

Marine mussels affix themselves to surfaces by use of a highly cross-linked, protein-based adhesive. Metal levels (e.g., Fe, Zn, Cu, Mn) of the cured glue are significantly concentrated relative to surrounding waters. Specific details on the reagents used by mussels to induce protein cross-linking are not known at this time. To provide insight on the cross-linking agents and reactions taking place while curing mussel glues, we performed a study in which various compounds were tested for the ability to bring about protein curing. A precursor to adhesion, with proteins containing the unusual amino acid 3,4-dihydroxyphenylalanine, was extracted from mussel feet. Potential cross-linking agents were mixed with this gelatinous pellet. The compressibility and shear properties of the resulting material were investigated by use of a penetration test. The reagents examined included simple metal ions (e.g., Na+, Zn2+), oxidizing transition metals (e.g., Fe3+, Cr2O7(2-)), nonmetallic oxidants (e.g., H2O2,IO4-), and oxidizing enzymes (e.g., tyrosinase). We found that protein curing was brought about by simple oxidants and transition metal ions. The results show that optimal curing occurs when the reagent is an oxidizing metal ion (e.g., MnO4-, Fe3+). We conclude that marine mussels are likely to employ Mn3+ and Fe3+ for protein cross-linking and adhesive synthesis. PMID:15875406

Monahan, Jennifer; Wilker, Jonathan J

2004-04-27

189

The impact of grafted modification of silicone surfaces with quantum-sized materials on protein adsorption and bacterial adhesion.  

PubMed

The majority of the infections associated with the biomedical devices including cardiovascular implants and catheters are instigated by the adhesion of bacteria including staphylococcus aureus, which is subsequently followed by biofilm formation. Keeping in mind the detrimental effect of bacterial adhesion, the objective of the study is to probe the impact of grafted modification of silicone surfaces with quantum-sized carbon on biofilm formation. Also, explored is the effect of protein adsorption on modified surface and its subsequent influence on bacterial adhesion. We compare and contrast the architecture and foot print of protein adsorption on unmodified and modified model silicone surfaces on bacterial adhesion. The study underscores that protein adsorption on quantum-sized carbon-grafted surface acts as a repellant for bacterial adhesion because of steric repulsion between the negatively charged protein and bacteria. Thus, we establish here the efficacy of modified surfaces in preventing biofilm formation. PMID:22707363

Nune, C; Xu, W; Misra, R D K

2012-06-15

190

The molecular mechanism of mediation of adsorbed serum proteins to endothelial cells adhesion and growth on biomaterials.  

PubMed

To explore molecular mechanism of mediation of adsorbed proteins to cell adhesion and growth on biomaterials, this study examined endothelial cell adhesion, morphology and viability on bare and titanium nitride (TiN) coated nickel titanium (NiTi) alloys and chitosan film firstly, and then identified the type and amount of serum proteins adsorbed on the three surfaces by proteomic technology. Subsequently, the mediation role of the identified proteins to cell adhesion and growth was investigated with bioinformatics analyses, and further confirmed by a series of cellular and molecular biological experiments. Results showed that the type and amount of adsorbed serum proteins associated with cell adhesion and growth was obviously higher on the alloys than on the chitosan film, and these proteins mediated endothelial cell adhesion and growth on the alloys via four ways. First, proteins such as adiponectin in the adsorbed protein layer bound with cell surface receptors to generate signal transduction, which activated cell surface integrins through increasing intracellular calcium level. Another way, thrombospondin 1 in the adsorbed protein layer promoted TGF-? signaling pathway activation and enhanced integrins expression. The third, RGD sequence containing proteins such as fibronectin 1, vitronectin and thrombospondin 1 in the adsorbed protein layer bound with activated integrins to activate focal adhesion pathway, increased focal adhesion formation and actin cytoskeleton organization and mediated cell adhesion and spreading. In addition, the activated focal adhesion pathway promoted the expression of cell growth related genes and resulted in cell proliferation. The fourth route, coagulation factor II (F2) and fibronectin 1 in the adsorbed protein layer bound with cell surface F2 receptor and integrin, activated regulation of actin cytoskeleton pathway and regulated actin cytoskeleton organization. PMID:23660250

Yang, Dayun; Lü, Xiaoying; Hong, Ying; Xi, Tingfei; Zhang, Deyuan

2013-05-07

191

Expression of stress proteins, adhesion molecules, and interleukin-8 in endothelial cells after preservation and reoxygenation.  

PubMed

Endothelial activation is a central feature of preservation-induced allograft injury. The present study aims at a quantitative assessment of stress proteins, adhesion molecules, and interleukin-8 in a cell culture-based model of organ preservation. Human umbilical vein endothelial cells were exposed to cold, hypoxic storage in University of Wisconsin (UW), histidine-tryptophane-ketoglutarate (HTK), and EuroCollins solutions for 8 h with subsequent rewarming/reoxygenation (rew/reox) for 1 and 4 h. A cell-based ELISA was designed for detection of heat shock proteins (HSP) 60 and 70, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial leukocyte adhesion molecule-1 (ELAM-1). Immunohistochemical staining was performed for comparison. Interleukin-8 was quantified by ELISA. HSP 70 was expressed after cold storage in HTK and EuroCollins solution and after rew/reox in all groups. A constitutive expression of HSP 60 was observed with further upregulation after rew/reox following cold storage in all experimental groups. ICAM-1 was clearly upregulated, but VCAM-1 showed only weak expression after cold storage and rew/reox. ELAM-1 was detectable in minimal amounts after cold storage but was considerably upregulated after 4 h of rew/reox. A significant increase of interleukin-8 release could be found after 4 h of rew/reox following storage in EuroCollins solution. Expression of stress proteins can be considered as a new parameter of preservation-associated endothelial activation. Apart from possible protective effects, allograft vasculopathy could be in part a consequence of the antigeneic potential of heat shock proteins connected with effects caused by adhesion molecules and inflammatory cytokines. PMID:10191034

Eberl, T; Amberger, A; Herold, M; Hengster, P; Steurer, W; Hochleitner, B W; Gnaiger, E; Margreiter, R

1999-03-01

192

Protein-tyrosine phosphatase PTPD1 regulates focal adhesion kinase autophosphorylation and cell migration.  

PubMed

PTPD1 is a cytosolic nonreceptor tyrosine phosphatase and a positive regulator of the Src-epidermal growth factor transduction pathway. We show that PTPD1 localizes along actin filaments and at adhesion plaques. PTPD1 forms a stable complex via distinct molecular modules with actin, Src tyrosine kinase, and focal adhesion kinase (FAK), a scaffold protein kinase enriched at adhesion plaques. Overexpression of PTPD1 promoted cell scattering and migration, short hairpin RNA-mediated silencing of endogenous PTPD1, or expression of PTPD1 mutants lacking either catalytic activity (PTPD1(C1108S)) or the FERM domain (PTPD1(Delta1-325)) significantly reduced cell motility. PTPD1 and Src catalytic activities were both required for epidermal growth factor-induced FAK autophosphorylation at its active site and for downstream propagation of ERK1/2 signaling. Our findings demonstrate that PTPD1 is a component of a multivalent scaffold complex nucleated by FAK at specific intracellular sites. By modulating Src-FAK signaling at adhesion sites, PTPD1 promotes the cytoskeleton events that induce cell adhesion and migration. PMID:18223254

Carlucci, Annalisa; Gedressi, Chiara; Lignitto, Luca; Nezi, Luigi; Villa-Moruzzi, Emma; Avvedimento, Enrico V; Gottesman, Max; Garbi, Corrado; Feliciello, Antonio

2008-01-26

193

The oxidase activity of vascular adhesion protein-1 (VAP-1) is essential for function.  

PubMed

Vascular adhesion protein-1 (VAP-1) has been implicated in the pathogenesis of inflammatory diseases and is suggested to play a role in immune cell trafficking. It is not clear whether this effect is mediated by the oxidase activity or by other features of the protein such as direct adhesion. In order to study the role of VAP-1 oxidase activity in vivo, we have generated mice carrying an oxidase activity-null VAP-1 protein. We demonstrate that the VAP-1 oxidase null mutant mice have a phenotype similar to the VAP-1 null mice in animal models of sterile peritonitis and antibody induced arthritis suggesting that the oxidase activity is responsible for the inflammatory function of VAP-1. PMID:23885334

Noonan, Thomas; Lukas, Susan; Peet, Gregory W; Pelletier, Josephine; Panzenbeck, Mark; Hanidu, Adedayo; Mazurek, Suzanne; Wasti, Ruby; Rybina, Irina; Roma, Teresa; Kronkaitis, Anthony; Shoultz, Alycia; Souza, Donald; Jiang, Huiping; Nabozny, Gerald; Modis, Louise Kelly

2013-06-15

194

Study of the Adhesion of Neurodegenerative Proteins on Plasma-Modified and Coated Polypropylene Surfaces.  

PubMed

The inner polymeric surface of an ELISA titration well is plasma-modified and coated with different surfactant molecules. The titration of neurodegenerative proteins markers (prion, Tau and ?-synuclein), previously demonstrated as more efficient with such modified tubes, is related to the adhesion behaviour of these proteins and their corresponding capture antibodies. The adhesion process is studied in terms of anchoring and specific mechanisms. The proteins and antibodies binding onto such modified surfaces is related to the substrate hydrophilic character calculated from the angle contact measure, to the polymer surface charge measured through the streaming potential determination at different pH and the inner surface roughness determined from AFM images. Furthermore, the influence of the blocking agent used during the ELISA titration is also studied. PMID:21944054

Poncin-Epaillard, F; Mille, C; Debarnot, D; Zorzi, W; Moualij, B El; Coudreuse, A; Legeay, G; Quadrio, I; Perret-Liaudet, A

2011-09-22

195

Adhesive water networks facilitate binding of protein interfaces  

Microsoft Academic Search

Water structure has an essential role in biological assembly. Hydrophobic dewetting has been documented as a general mechanism for the assembly of hydrophobic surfaces; however, the association mechanism of hydrophilic interfaces remains mysterious and cannot be explained by simple continuum water models that ignore the solvent structure. Here we study the association of two hydrophilic proteins using unbiased extensive molecular

Mazen Ahmad; Wei Gu; Tihamér Geyer; Volkhard Helms

2011-01-01

196

Adhesive strength and curing rate of marine mussel protein extracts on porcine small intestinal submucosa.  

PubMed

An adhesive protein extracted from marine mussels (Mytilus edulis) was used to bond strips of connective tissue for the purpose of evaluating the use of curing agents to improve adhesive curing. Specifically, mussel adhesive protein solution (MAPS, 0.5mM dihydroxyphenylalanine) was applied, with or without the curing agents, to the ends of two overlapping strips of porcine small intestinal submucosa (SIS). The bond strength of this lap joint was determined after curing for 1h at room temperature (25 degrees C). The strength of joints formed using only MAPS or with only the ethyl, butyl or octyl cyanoacrylate adhesives were determined. Although joints bonded using ethyl cyanoacrylate were strongest, those using MAPS were stronger than those using butyl and octyl cyanoacrylates. The addition of 25mM solutions of the transition metal ions V5+, Fe3+ and Cr6+, which are all oxidants, increased the bond strength of the MAPS joints. The V5+ gave the strongest bonds and the Fe3+ the second strongest. In subsequent tests with V5+ and Fe3+ solutions, the bond strength increased with V5+ concentration, but it did not increase with Fe3+ concentration. Addition of 250mM V5+ gave a very strong bond. PMID:17434815

Ninan, Lal; Stroshine, R L; Wilker, J J; Shi, Riyi

2007-04-16

197

Role of adhesive proteins in platelet tumor interaction in vitro and metastasis formation in vivo.  

PubMed Central

Platelet-adhesive protein-tumor cell interaction was studied in vitro and in vivo. Monoclonal antibody 10E5, which inhibits binding of fibronectin and von Willebrand factor to the platelet membrane glycoprotein GPIIb-GPIIIa complex, inhibited the binding of mouse CT26 and human HCT8 colon carcinoma cells to platelets by 63-65%, whereas an irrelevant monoclonal antibody, 3B2, had no effect. Monoclonal antibody 6D1, which inhibits binding of von Willebrand factor to GPIb, also had no effect. RGDS, a tetrapeptide that represents the adhesive domain of fibronectin and von Willebrand factor inhibited binding of the tumors to platelets by 64-69%. Monospecific polyclonal antifibronectin antibody inhibited binding by 60-82%; anti-von Willebrand factor antibody inhibited binding by 75-81%. In vivo, polyclonal monospecific anti-mouse von Willebrand factor antibody inhibited pulmonary metastases induced by CT26 tumor cells by 53-64%, B16a amelanotic melanoma cells by 45% and T241 Lewis bladder cells by 46% without induction of thrombocytopenia. Pulmonary metastases with CT26 cells could be inhibited by induction of thrombocytopenia, and reconstituted by infusion of either murine or human platelets. Reconstitution of pulmonary metastases with human platelets could be inhibited 77% by preincubation of human platelets with monoclonal antibody 10E5 before infusion of platelets into mice. Thus, platelets appear to contribute to metastases by their adhesive interaction with tumor cells via the adhesive proteins fibronectin and von Willebrand factor.

Karpatkin, S; Pearlstein, E; Ambrogio, C; Coller, B S

1988-01-01

198

The role of intracellular protein O-glycosylation in cell adhesion and disease?  

PubMed Central

Post-translational protein modification, including phosphorylation, is generally quick and reversible, facilitating rapid biologic adjustments to altered cellular physiologic demands. In addition to protein phosphorylation, other post-translational modifications have been identified. Intracellular protein O-glycosylation, the addition of the simple sugar O-linked N-acetylglucosamine (O-GlcNAc) to serine/threonine residues, is a relatively recently identified post-translational modification that has added to the complexity by which protein function is regulated. Two intracellular enzymes, O-GlcNAc transferase and O-GlcNAcase, catalyze the addition and removal, respectively, of O-GlcNAc to serine and threonine side-chain hydroxyl groups. Numerous proteins, including enzymes, transcription factors, receptors and structural proteins have been shown to be modified by intracellular O-glycosylation. In this review, the mechanism and relevance of O-GlcNAc protein modification are discussed in the context of cell adhesion and several representative diseases.

Bektas, Meryem; Rubenstein, David S.

2011-01-01

199

Surface proteins of the gliding bacterium Cytophaga sp. strain U67 and its mutants defective in adhesion and motility  

SciTech Connect

Surface proteins of the gliding bacterium Cytophaga sp. strain U67 that make contact with glass substrata were radioiodinated, using a substratum-immobilized catalyst (Iodo-Gen). At least 15 polypeptides were iodinated, fewer than the number labeled by surface biotinylation of whole cells; these polypeptides define the set of possible candidates for the surface protein(s) that mediates gliding-associated substratum adhesion. The labeling of three adhesion-defective mutants exhibited two characteristic patterns of surface iodination which involved addition, loss, or alteration of several polypeptides of high molecular weight. An adhesion-competent revertant of mutant Adh3 and one of Adh2 exhibited the wild-type labeling pattern. Two other Adh2 revertants resembled their adhesion-defective parent. The labeling pattern of surface polypeptides of a nongliding but adhesive cell strain was similar to that of the wild type.

Burchard, R.P.; Bloodgood, R.A. (Univ. of Maryland Baltimore County (USA))

1990-06-01

200

Surface proteins of the gliding bacterium Cytophaga sp. strain U67 and its mutants defective in adhesion and motility.  

PubMed Central

Surface proteins of the gliding bacterium Cytophaga sp. strain U67 that make contact with glass substrata were radioiodinated, using a substratum-immobilized catalyst (Iodo-Gen). At least 15 polypeptides were iodinated, fewer than the number labeled by surface biotinylation of whole cells; these polypeptides define the set of possible candidates for the surface protein(s) that mediates gliding-associated substratum adhesion. The labeling of three adhesion-defective mutants exhibited two characteristic patterns of surface iodination which involved addition, loss, or alteration of several polypeptides of high molecular weight. An adhesion-competent revertant of mutant Adh3 and one of Adh2 exhibited the wild-type labeling pattern. Two other Adh2 revertants resembled their adhesion-defective parent. The labeling pattern of surface polypeptides of a nongliding but adhesive cell strain was similar to that of the wild type. Images

Burchard, R P; Bloodgood, R A

1990-01-01

201

Extracellular matrix protein patterns guide human chondrocytes adhesion and alignment characterized by vimentin and matrilin-3.  

PubMed

The main purpose of the present study is to investigate the influences of collagen VI (col-VI) patterns on human chondrocytes behaviors. To this end, col-VI stripes with varying width and interstripe spacing are created on polystyrene (PS) surfaces by microcontact printing (?CP). Human chondrocytes are then seeded on these protein patterns and the cell adhesion and alignment are investigated by staining the vimentin and matrilin-3 secreted by seeded chondrocytes. The results indicate that the cells preferentially attach onto the protein areas, rendering cell patterns and the elongated cell shapes. The pattern dimensions can significantly influence cell adhesion, spreading and orientation. The stripe protein patterns can guide cell adhesion and alignment. The cell morphologies can be controlled by carefully designing the pattern shapes and sizes. Our results suggest that the protein patterns can be used to modify biomaterials' surfaces for selective cell-binding and cell alignment. It could provide some cues for the development of novel implantable biomaterials, such as tissue-engineered scaffolds for cartilage replacement, where specific cell alignment is needed. PMID:23107951

Pan, Chang-Jiang; Ding, Hong-Yan; Dong, Yun-Xiao

2012-09-13

202

Vascular adhesion protein-1 regulates leukocyte transmigration rate in the retina during diabetes.  

PubMed

Vascular adhesion protein-1 (VAP-1) is an endothelial adhesion molecule that possesses semicarbazide-sensitive amine oxidase (SSAO) activity and is involved in leukocyte recruitment. Leukocyte adhesion to retinal vessels is a predominant feature of experimentally induced diabetic retinopathy (DR). However, the role of VAP-1 in this process is unknown. Diabetes was induced by i.p. injection of Streptozotocin in Long-Evans rats. The specific inhibitor of VAP-1, UV-002, was administered by daily i.p. injections. The expression of VAP-1 mRNA in the retinal extracts of normal and diabetic animals was measured by real-time quantitative polymerase chain reaction (PCR). Firm leukocyte adhesion was quantified in retinal flatmounts after intravascular staining with concanavalin A (ConA). Leukocyte transmigration rate was quantified by in vivo acridine orange leukocyte staining (AOLS). In diabetic rats, the rate of leukocyte transmigration into the retinal tissues of live animals was significantly increased, as determined by AOLS. When diabetic animals were treated with daily injections of the VAP-1 inhibitor (0.3 mg/kg), leukocyte transmigration rate was significantly reduced (P < 0.05). However, firm adhesion of leukocytes in diabetic animals treated with the inhibitor did not differ significantly from vehicle-treated diabetic controls. This work provides evidence for an important role of VAP-1 in the recruitment of leukocyte to the retina in experimental DR. Our results reveal the critical contribution of VAP-1 to leukocyte transmigration, with little impact on firm leukocyte adhesion in the retinas of diabetic animals. VAP-1 inhibition might be beneficial in the treatment of DR. PMID:19635478

Noda, Kousuke; Nakao, Shintaro; Zandi, Souska; Engelstädter, Verena; Mashima, Yukihiko; Hafezi-Moghadam, Ali

2009-07-25

203

Vascular Adhesion Protein-1 Regulates Leukocyte Transmigration Rate in the Retina During Diabetes  

PubMed Central

Vascular adhesion protein-1 (VAP-1) is an endothelial adhesion molecule that possesses semicarbazide-sensitive amine oxidase (SSAO) activity and is involved in leukocyte recruitment. Leukocyte adhesion to retinal vessels is a predominant feature of experimentally induced diabetic retinopathy (DR). However, the role of VAP-1 in this process is unknown. Diabetes was induced by i.p. injection of Streptozotocin in Long–Evans rats. The specific inhibitor of VAP-1, UV-002, was administered by daily i.p. injections. The expression of VAP-1 mRNA in the retinal extracts of normal and diabetic animals was measured by real time quantitative polymerase chain reaction (PCR). Firm leukocyte adhesion was quantified in retinal flatmounts after intravascular staining with concanavalin A (ConA). Leukocyte transmigration rate was quantified by in vivo acridine orange leukocyte staining (AOLS). In diabetic rats, the rate of leukocyte transmigration into the retinal tissues of live animals was significantly increased, as determined by AOLS. When diabetic animals were treated with daily injections of the VAP-1 inhibitor (0.3mg/kg), leukocyte transmigration rate was significantly reduced (P<0.05). However, firm adhesion of leukocytes in diabetic animals treated with the inhibitor did not differ significantly from vehicle-treated diabetic controls. This work provides evidence for an important role of VAP-1 in the recruitment of leukocyte to the retina in experimental DR. Our results reveal the critical contribution of VAP-1 to leukocyte transmigration, with little impact on firm leukocyte adhesion in the retinas of diabetic animals. VAP-1 inhibition might be beneficial in the treatment of DR.

Noda, Kousuke; Nakao, Shintaro; Zandi, Souska; Engelstadter, Verena; Mashima, Yukihiko; Hafezi-Moghadam, Ali

2009-01-01

204

Adhesive Surface Proteins of Erysipelothrix rhusiopathiae Bind to Polystyrene, Fibronectin, and Type I and IV Collagens  

Microsoft Academic Search

Erysipelothrix rhusiopathiae is a gram-positive bacterium that causes erysipelas in animals and erysipeloid in humans. We found two adhesive surface proteins of E. rhusiopathiae and determined the nucleotide sequences of the genes, which were colocalized and designated rspA and rspB. The two genes were present in all of the serovars of E. rhusiopathiae strains examined. The deduced RspA and RspB

Yoshihiro Shimoji; Yohsuke Ogawa; Makoto Osaki; Hidenori Kabeya; Soichi Maruyama; Takeshi Mikami; Tsutomu Sekizaki

2003-01-01

205

Expression of Stress Proteins, Adhesion Molecules, and Interleukin8 in Endothelial Cells after Preservation and Reoxygenation  

Microsoft Academic Search

Endothelial activation is a central feature of preservation-induced allograft injury. The present study aims at a quantitative assessment of stress proteins, adhesion molecules, and interleukin-8 in a cell culture-based model of organ preservation. Human umbilical vein endothelial cells were exposed to cold, hypoxic storage in University of Wisconsin (UW), histidine-tryptophane-ketoglutarate (HTK), and EuroCollins solutions for 8 h with subsequent rewarming\\/reoxygenation

Thomas Eberl; Albert Amberger; Manfred Herold; Paul Hengster; Wolfgang Steurer; Boris W. Hochleitner; Erich Gnaiger; Raimund Margreiter

1999-01-01

206

Cloning and sequencing of the gene encoding mussel adhesive protein from Mytilus sp. JHX-2002  

Microsoft Academic Search

The cDNA of msfp-1 encoding mussel adhesive plaque protein (MSFP-1) was obtained from the total RNA of Mytilus sp. JHX-2002 by RT-PCR. The DNA of msfp-1 was amplified by PCR from the genomic DNA of Mytilus sp. JHX-2002. The cDNA and DNA of msfp-1 were sequenced, respectively. As the results shown that msfp-1 is 591 bp encoding 196 amino acids

Yun Ji Wang; Xin Zheng; Ling Hua Zhang; Yoshiyuki Ohta

2004-01-01

207

Metavinculin: New insights into functional properties of a muscle adhesion protein.  

PubMed

Metavinculin is a muscle-specific splice variant of the ubiquitously expressed cytoskeletal adaptor protein vinculin. Both proteins are thought to be co-expressed in all muscle types where they co-localize to microfilament-associated adhesion sites. It has been shown that a metavinculin-specific insertion of 68 amino acids alters the biochemical properties of the five-helix bundle in the tail domain. Here, we demonstrate that the metavinculin-specific helix H1' plays an important role for protein stability of the tail domain, since a point mutation in this helix, R975W, which is associated with the occurrence of dilated cardiomyopathy in man, further decreases thermal stability of the metavinculin tail domain. In striated muscle progenitor cells (myoblasts), both, metavinculin and the R975W mutant show significantly reduced, albeit distinctive residency and exchange rates in adhesion sites as compared to vinculin. In contrast to previous studies, we show that metavinculin is localized in a muscle fiber type-dependent fashion to the costameres of striated muscle, reflecting the individual metabolic and physiological status of a given muscle fiber. Metavinculin expression is highest in fast, glycolytic muscle fibers and virtually absent in M. diaphragmaticus, a skeletal muscle entirely lacking fast, glycolytic fibers. In summary, our data suggest that metavinculin enrichment in attachment sites of muscle cells leads to higher mechanical stability of adhesion complexes allowing for greater shear force resistance. PMID:23159629

Thoss, Florian; Dietrich, Franziska; Punkt, Karla; Illenberger, Susanne; Rottner, Klemens; Himmel, Mirko; Ziegler, Wolfgang H

2012-11-14

208

Synaptic Cell Adhesion Proteins and Synaptogenesis in the Mammalian Central Nervous System  

NASA Astrophysics Data System (ADS)

Synapses are asymmetric cell-cell contacts, typically formed between the presynaptic axon terminal of a "sending" nerve cell and the postsynaptic dendrite, the soma or - in some cases - the axon of a "receiving" one. The presynaptic axon terminal is specialized for the complex membrane trafficking mechanisms that underlie regulated secretion of neurotransmitter, while the postsynapse is uniquely specialized for signal transduction. Synaptogenesis, the formation of functional synapses, is the final step in the development of the central nervous system. In the mammalian brain it results in the establishment of a neural network, connecting some 1012 nerve cells with up to 1015 synapses. In principle, synaptogenesis takes place in two consecutive steps that are most likely mediated by cell adhesion molecules. First, an arriving axonal growth cone identifies its appropriate partner cell, creating an initial contact, and, second, specific axonal and dendritic protein components are recruited to this initial contact site, forming a functional synapse. Three cell adhesion systems have recently been shown to be specifically enriched at synaptic contacts: the cadherin/catenin system, the cadherinlike neuronal receptors, and the ?-neurexin/neuroligin system. Components of all three cell adhesion systems have been localized to synaptic contacts using immunogold electron microscopy but are also present outside of synapses. The present short review discusses the possible role of these synaptic cell adhesion molecules in synaptogenesis.

Brose, N.

209

Protein kinase C-? is required for murine neutrophil recruitment and adhesion strengthening under flow.  

PubMed

Protein kinase C (PKC)-? is involved in T cell activation via regulating the avidity of the ?(2) integrin LFA-1 in the immunological synapse. LFA-1 also mediates leukocyte adhesion. To investigate the role of PKC-? in neutrophil adhesion, we performed intravital microscopy in cremaster venules of mice reconstituted with bone marrow from LysM-GFP(+) (wild-type [WT]) and PKC-? gene-deficient (Prkcq(-/-)) mice. Following stimulation with CXCL1, both WT and Prkcq(-/-) cells became adherent. Although most WT neutrophils remained adherent for at least 180 s, 50% of Prkcq(-/-) neutrophils were detached after 105 s and most by 180 s. Upon CXCL1 injection, rolling of all WT neutrophils stopped for 90 s, but rolling of Prkcq(-/-) neutrophils started 30 s after CXCL1 stimulation. A similar neutrophil adhesion defect was seen in vitro, and spreading of Prkcq(-/-) neutrophils was delayed. Prkcq(-/-) neutrophil recruitment was impaired in fMLP-induced transmigration into the cremaster muscle, thioglycollate-induced peritonitis, and LPS-induced lung injury. We conclude that PKC-? mediates integrin-dependent neutrophil functions and is required to sustain neutrophil adhesion in postcapillary venules in vivo. These findings suggest that the role of PKC-? in outside-in signaling following engagement of neutrophil integrins is relevant for inflammation in vivo. PMID:22403440

Bertram, Anna; Zhang, Hong; von Vietinghoff, Sibylle; de Pablo, Carmen; Haller, Hermann; Shushakova, Nelli; Ley, Klaus

2012-03-07

210

Human Siglec-10 can bind to vascular adhesion protein-1 and serves as its substrate  

PubMed Central

Leukocytes migrate from the blood into areas of inflammation by interacting with various adhesion molecules on endothelial cells. Vascular adhesion protein-1 (VAP-1) is a glycoprotein expressed on inflamed endothelium where it plays a dual role: it is both an enzyme that oxidizes primary amines and an adhesin that is involved in leukocyte trafficking to sites of inflammation. Although VAP-1 was identified more than 15 years ago, the counterreceptor(s) for VAP-1 on leukocytes has remained unknown. Here we have identified Siglec-10 as a leukocyte ligand for VAP-1 using phage display screenings. The binding between Siglec-10 and VAP-1 was verified by different adhesion assays, and this interaction was also consistent with molecular modeling. Moreover, the interaction between Siglec-10 and VAP-1 led to increased hydrogen peroxide production, indicating that Siglec-10 serves as a substrate for VAP-1. Thus, the Siglec-10–VAP-1 interaction seems to mediate lymphocyte adhesion to endothelium and has the potential to modify the inflammatory microenvironment via the enzymatic end products.

Kivi, Elina; Elima, Kati; Aalto, Kristiina; Nymalm, Yvonne; Auvinen, Kaisa; Koivunen, Erkki; Otto, Diana M.; Crocker, Paul R.; Salminen, Tiina A.; Salmi, Marko

2009-01-01

211

The direction of gut looping is established by changes in the extracellular matrix and in cell:cell adhesion  

PubMed Central

The counterclockwise coiling of the intestines is initiated by a leftward tilt of the primitive gut tube, imparted by left–right asymmetries in the architecture of the dorsal mesentery. In silico analysis suggests that this is achieved by synergistic changes in its epithelium and mesenchyme. Within the mesenchymal compartment, cells are more densely packed on the left than on the right. In silico results indicate that this property can result from asymmetries in both extracellular matrix (ECM) and cell:cell adhesion. We find that the dorsal mesentery ECM is indeed left–right asymmetric and moreover that the adhesion molecule N-cadherin is expressed exclusively on the left side. These asymmetries are regulated by the asymmetrically expressed transcription factors Pitx2 and Isl1. Functional studies demonstrate that N-cadherin acts upstream of the changes in the ECM and is both necessary and sufficient to explain the asymmetric packing of the mesenchymal cells.

Kurpios, Natasza A.; Ibanes, Marta; Davis, Nicole M.; Lui, Wei; Katz, Tamar; Martin, James F.; Belmonte, Juan Carlos Izpisua; Tabin, Clifford J.

2008-01-01

212

Chick neural retina adhesion and survival molecule is a retinol-binding protein  

SciTech Connect

A 20,000-D protein called purpurin has recently been isolated from the growth-conditioned medium of cultured embryonic chick neural retina cells. Purpurin is a constituent of adherons and promotes cell-adheron adhesion by interacting with a cell surface heparan sulfate proteoglycan. It also prolongs the survival of cultured neural retina cells. This paper shows that purpurin is a secretory protein that has sequence homology with a human protein synthesized in the liver that transports retinol in the blood, the serum retinol-binding protein (RBP). Purpurin binds (/sup 3/H)retinol, and both purpurin and chick serum RBP stimulate the adhesion of neural retina cells, although the serum protein is less active than purpurin. Purpurin and the serum RBP are, however, different molecules, for the serum protein is approx.3.000 D larger than purpurin and has different silver-staining characteristics. Finally, purpurin supports the survival of dissociated ciliary ganglion cells, indicating that RBPs can act as ciliary neurotrophic factors.

Schubert, D.; LaCorbiere, M.; Esch, F.

1986-01-01

213

Protein Adhesion and Ion Substitution (on/in)to Minerals  

NASA Astrophysics Data System (ADS)

Arsenic and pathogenic prion protein-scrapie (PrPsc) are important contaminants which may soil and water for decades, unless they are removed by sorption. Two sorption mechanisms will be discussed, namely the organics (Prp and single aminoacid) adsorption on clay and the arsenic substitution in gypsum. The elucidation of these contrasted mechanisms will be shown to request complementary molecular-mechanical simulations with experimental spectroscopic investigations. As first example, structural studies performed at ILL/ESRF on As-doped gypsum (CaSO4 2H2O) using neutron and X-ray diffraction data and EXAFS were performed to determine how As fits into the bulk of gypsum structure. The combined Rietveld analysis of neutron and X-ray diffraction data shows an expansion of the unit cell volume proportional to the As concentration within the samples. to-sulfate substitution mechanisms were used as simulation starting hypotheses. DFT-based simulations (Mulliken analysis) were used to interpret charge distribution and to show that among the possible mechanisms, a sulphate substitution by either protonated, or fully deprotonated, arsenate ion, only the protonated arsenate substitution could best fit the EXAFS data. In the second example, we used Molecular Dynamics to understand the mechanism of strong binding of the pathogenic PrP peptide with clay mineral surfaces. We modeled only the infectious moiety, PrP92-138, of the whole PrPsc structure, with explicitly solvating water molecules in contact with the cleavage plane of pyrophillite, as a model for montmorillonite without any cationic substitution. Partial residual negative charges on the cleavage plane were balanced with K+ ions. The peptide anchored to the clay surface via up to 10 hydrogen bonds from lysine and histidine residues to oxygen atoms of the siloxane cavities, and a total adsorption energy of 3465 KJ.mol-1 was obtained. Our results were compared to the one obtained by chemical and thermal analysis, 23Na, 1H, 13C solid state NMR and MD computation on sorption of single lysine amino acid on model synthetic Na-montmorillonite. Our data provide further insight about interactions between lysine and montmorillonite which depend strongly on lysine concentration.

Charlet, L.; Fernandez Martinez, A.; Chapron, Y.; Sahai, N.; Cuello, G.; Brendle, J.; Marichal, C.

2008-12-01

214

Lectin Receptor Kinases Participate in Protein-Protein Interactions to Mediate Plasma Membrane-Cell Wall Adhesions in Arabidopsis1  

PubMed Central

Interactions between plant cell walls and plasma membranes are essential for cells to function properly, but the molecules that mediate the structural continuity between wall and membrane are unknown. Some of these interactions, which are visualized upon tissue plasmolysis in Arabidopsis (Arabidopsis thaliana), are disrupted by the RGD (arginine-glycine-aspartic acid) tripeptide sequence, a characteristic cell adhesion motif in mammals. In planta induced-O (IPI-O) is an RGD-containing protein from the plant pathogen Phytophthora infestans that can disrupt cell wall-plasma membrane adhesions through its RGD motif. To identify peptide sequences that specifically bind the RGD motif of the IPI-O protein and potentially play a role in receptor recognition, we screened a heptamer peptide library displayed in a filamentous phage and selected two peptides acting as inhibitors of the plasma membrane RGD-binding activity of Arabidopsis. Moreover, the two peptides also disrupted cell wall-plasma membrane adhesions. Sequence comparison of the RGD-binding peptides with the Arabidopsis proteome revealed 12 proteins containing amino acid sequences in their extracellular domains common with the two RGD-binding peptides. Eight belong to the receptor-like kinase family, four of which have a lectin-like extracellular domain. The lectin domain of one of these, At5g60300, recognized the RGD motif both in peptides and proteins. These results imply that lectin receptor kinases are involved in protein-protein interactions with RGD-containing proteins as potential ligands, and play a structural and signaling role at the plant cell surfaces.

Gouget, Anne; Senchou, Virginie; Govers, Francine; Sanson, Arnaud; Barre, Annick; Rouge, Pierre; Pont-Lezica, Rafael; Canut, Herve

2006-01-01

215

Amalgam, an axon guidance Drosophila adhesion protein belonging to the immunoglobulin superfamily: Over-expression, purification and biophysical characterization  

Microsoft Academic Search

Amalgam, a multi-domain member of the immunoglobulin superfamily, possesses homophilic and heterophilic cell adhesion properties. It is required for axon guidance during Drosophila development in which it interacts with the extracellular domain of the transmembrane protein, neurotactin, to promote adhesion. Amalgam was heterologously expressed in Pichia pastoris, and the secreted protein product, bearing an NH2-terminal His6Tag, was purified from the

Tzviya Zeev-Ben-Mordehai; Aviv Paz; Yoav Peleg; Lilly Toker; Sharon G. Wolf; Edwin H. Rydberg; Joel L. Sussman; Israel Silman

2009-01-01

216

Fabrication of a Dual Substrate Display to Test Roles of Cell Adhesion Proteins in Vesicle Targeting to Plasma Membrane Domains  

PubMed Central

While much is known of the molecular machinery involved in protein sorting during exocytosis, less is known about the spatial regulation of exocytosis at the plasma membrane (PM). This study outlines a novel method, Dual Substrate Display, used to formally test the hypothesis that E-cadherin-mediated adhesion directs basolateral vesicle exocytosis to specific sites at the PM. We show that vesicles containing the basolateral marker protein VSV-G preferentially target to sites of adhesion to E-cadherin rather than collagen VI or a control peptide. These results support the hypothesis that E-cadherin adhesion initiates signaling at the PM resulting in targeted sites for exocytosis.

Hunt, Stephen J.; Nelson, W. James

2009-01-01

217

Spatiotemporal expression profiling of proteins in rat sciatic nerve regeneration using reverse phase protein arrays  

PubMed Central

Background Protein expression profiles throughout 28 days of peripheral nerve regeneration were characterized using an established rat sciatic nerve transection injury model. Reverse phase protein microarrays were used to identify the spatial and temporal expression profile of multiple proteins implicated in peripheral nerve regeneration including growth factors, extracellular matrix proteins, and proteins involved in adhesion and migration. This high-throughput approach enabled the simultaneous analysis of 3,360 samples on a nitrocellulose-coated slide. Results The extracellular matrix proteins collagen I and III, laminin gamma-1, fibronectin, nidogen and versican displayed an early increase in protein levels in the guide and proximal sections of the regenerating nerve with levels at or above the baseline expression of intact nerve by the end of the 28 day experimental course. The 28 day protein levels were also at or above baseline in the distal segment however an early increase was only noted for laminin, nidogen, and fibronectin. While the level of epidermal growth factor, ciliary neurotrophic factor and fibroblast growth factor-1 and -2 increased throughout the experimental course in the proximal and distal segments, nerve growth factor only increased in the distal segment and fibroblast growth factor-1 and -2 and nerve growth factor were the only proteins in that group to show an early increase in the guide contents. As expected, several proteins involved in cell adhesion and motility; namely focal adhesion kinase, N-cadherin and ?-catenin increased earlier in the proximal and distal segments than in the guide contents reflecting the relatively acellular matrix of the early regenerate. Conclusions In this study we identified changes in expression of multiple proteins over time linked to regeneration of the rat sciatic nerve both demonstrating the utility of reverse phase protein arrays in nerve regeneration research and revealing a detailed, composite spatiotemporal expression profile of peripheral nerve regeneration.

2012-01-01

218

Mitogen-activated protein kinase modulates ethanol inhibition of cell adhesion mediated by the L1 neural cell adhesion molecule  

PubMed Central

There is a genetic contribution to fetal alcohol spectrum disorders (FASD), but the identification of candidate genes has been elusive. Ethanol may cause FASD in part by decreasing the adhesion of the developmentally critical L1 cell adhesion molecule through interactions with an alcohol binding pocket on the extracellular domain. Pharmacologic inhibition or genetic knockdown of ERK2 did not alter L1 adhesion, but markedly decreased ethanol inhibition of L1 adhesion in NIH/3T3 cells and NG108-15 cells. Likewise, leucine replacement of S1248, an ERK2 substrate on the L1 cytoplasmic domain, did not decrease L1 adhesion, but abolished ethanol inhibition of L1 adhesion. Stable transfection of NIH/3T3 cells with human L1 resulted in clonal cell lines in which L1 adhesion was consistently sensitive or insensitive to ethanol for more than a decade. ERK2 activity and S1248 phosphorylation were greater in ethanol-sensitive NIH/3T3 clonal cell lines than in their ethanol-insensitive counterparts. Ethanol-insensitive cells became ethanol sensitive after increasing ERK2 activity by transfection with a constitutively active MAP kinase kinase 1. Finally, embryos from two substrains of C57BL mice that differ in susceptibility to ethanol teratogenesis showed corresponding differences in MAPK activity. Our data suggest that ERK2 phosphorylation of S1248 modulates ethanol inhibition of L1 adhesion by inside-out signaling and that differential regulation of ERK2 signaling might contribute to genetic susceptibility to FASD. Moreover, identification of a specific locus that regulates ethanol sensitivity, but not L1 function, might facilitate the rational design of drugs that block ethanol neurotoxicity.

Dou, Xiaowei; Wilkemeyer, Michael F.; Menkari, Carrie E.; Parnell, Scott E.; Sulik, Kathleen K.; Charness, Michael E.

2013-01-01

219

Mitogen-activated protein kinase modulates ethanol inhibition of cell adhesion mediated by the L1 neural cell adhesion molecule.  

PubMed

There is a genetic contribution to fetal alcohol spectrum disorders (FASD), but the identification of candidate genes has been elusive. Ethanol may cause FASD in part by decreasing the adhesion of the developmentally critical L1 cell adhesion molecule through interactions with an alcohol binding pocket on the extracellular domain. Pharmacologic inhibition or genetic knockdown of ERK2 did not alter L1 adhesion, but markedly decreased ethanol inhibition of L1 adhesion in NIH/3T3 cells and NG108-15 cells. Likewise, leucine replacement of S1248, an ERK2 substrate on the L1 cytoplasmic domain, did not decrease L1 adhesion, but abolished ethanol inhibition of L1 adhesion. Stable transfection of NIH/3T3 cells with human L1 resulted in clonal cell lines in which L1 adhesion was consistently sensitive or insensitive to ethanol for more than a decade. ERK2 activity and S1248 phosphorylation were greater in ethanol-sensitive NIH/3T3 clonal cell lines than in their ethanol-insensitive counterparts. Ethanol-insensitive cells became ethanol sensitive after increasing ERK2 activity by transfection with a constitutively active MAP kinase kinase 1. Finally, embryos from two substrains of C57BL mice that differ in susceptibility to ethanol teratogenesis showed corresponding differences in MAPK activity. Our data suggest that ERK2 phosphorylation of S1248 modulates ethanol inhibition of L1 adhesion by inside-out signaling and that differential regulation of ERK2 signaling might contribute to genetic susceptibility to FASD. Moreover, identification of a specific locus that regulates ethanol sensitivity, but not L1 function, might facilitate the rational design of drugs that block ethanol neurotoxicity. PMID:23431142

Dou, Xiaowei; Wilkemeyer, Michael F; Menkari, Carrie E; Parnell, Scott E; Sulik, Kathleen K; Charness, Michael E

2013-02-19

220

Recombinant Probiotic Expressing Listeria Adhesion Protein Attenuates Listeria monocytogenes Virulence In Vitro  

PubMed Central

Background Listeria monocytogenes, an intracellular foodborne pathogen, infects immunocompromised hosts. The primary route of transmission is through contaminated food. In the gastrointestinal tract, it traverses the epithelial barrier through intracellular or paracellular routes. Strategies to prevent L. monocytogenes entry can potentially minimize infection in high-risk populations. Listeria adhesion protein (LAP) aids L. monocytogenes in crossing epithelial barriers via the paracellular route. The use of recombinant probiotic bacteria expressing LAP would aid targeted clearance of Listeria from the gut and protect high-risk populations from infection. Methodology/Principal Findings The objective was to investigate the ability of probiotic bacteria or LAP-expressing recombinant probiotic Lactobacillus paracasei (LbpLAP) to prevent L. monocytogenes adhesion, invasion, and transwell-based transepithelial translocation in a Caco-2 cell culture model. Several wild type probiotic bacteria showed strong adhesion to Caco-2 cells but none effectively prevented L. monocytogenes infection. Pre-exposure to LbpLAP for 1, 4, 15, or 24 h significantly (P<0.05) reduced adhesion, invasion, and transepithelial translocation of L. monocytogenes in Caco-2 cells, whereas pre-exposure to parental Lb. paracasei had no significant effect. Similarly, LbpLAP pre-exposure reduced L. monocytogenes translocation by as much as 46% after 24 h. LbpLAP also prevented L. monocytogenes-mediated cell damage and compromise of tight junction integrity. Furthermore, LbpLAP cells reduced L. monocytogenes-mediated cell cytotoxicity by 99.8% after 1 h and 79% after 24 h. Conclusions/Significance Wild type probiotic bacteria were unable to prevent L. monocytogenes infection in vitro. In contrast, LbpLAP blocked adhesion, invasion, and translocation of L. monocytogenes by interacting with host cell receptor Hsp60, thereby protecting cells from infection. These data show promise for the use of recombinant probiotics in preventing L. monocytogenes infection in high-risk populations.

Koo, Ok Kyung; Amalaradjou, Mary Anne Roshni; Bhunia, Arun K.

2012-01-01

221

Surface modification of polypyrrole/biopolymer composites for controlled protein and cellular adhesion.  

PubMed

The ability to control the interaction between proteins and cells with biomaterials is critical for the effective application of materials for a variety of biomedical applications. Herein, the surface modification of the biological dopant dextran sulphate-doped polypyrrole (PPy-DS) with poly(ethylene glycol) to generate a biomaterial interface that is highly resistant to protein and cellular adhesion is described. Thiolated poly(ethylene glycol) (PEG-thiol) was covalently bound to PPy-DS backbone via a thiol-ene reaction. The surface resistance to an extracellular matrix protein fibronectin increased with increasing molecular weight and concentration of PEG-thiol, and was further optimised via increasing the reaction temperature and the pH of the reactant aqueous solution. Optimised surface modification conditions substantially reduced interfacial protein adsorption, with the complete inhibition of adhesion and colonisation by primary mouse myoblasts. PEG-thiol-modified inherently conducting polymers are highly protein resistant multifunctional materials that are promising compounds for a range of biomedical and aquatic applications. PMID:24063598

Molino, Paul J; Zhang, Binbin; Wallace, Gordon G; Hanks, Timothy W

2013-09-24

222

Bacterial adhesion to protein-coated surfaces: An AFM and QCM-D study  

NASA Astrophysics Data System (ADS)

Bacterial adhesion to biomaterials, mineral surfaces, or other industrial surfaces is strongly controlled by the way bacteria interact with protein layers or organic matter and other biomolecules that coat the materials. Despite this knowledge, many studies of bacterial adhesion are performed under clean conditions, instead of in the presence of proteins or organic molecules. We chose fetal bovine serum (FBS) as a model protein, and prepared FBS films on quartz crystals. The thickness of the FBS layer was characterized using atomic force microscopy (AFM) imaging under liquid and quartz crystal microbalance with dissipation (QCM-D). Next, we characterized how the model biomaterial surface would interact with the nocosomial pathogen Staphylococcus epidermidis. An AFM probe was coated with S. epidermidis cells and used to probe a gold slide that had been coated with FBS or another protein, fibronectin (FN). These experiments show that AFM and QCM-D can be used in complementary ways to study the complex interactions between bacteria, proteins, and surfaces.

Strauss, Joshua; Liu, Yatao; Camesano, Terri A.

2009-09-01

223

Optical Regulation of Protein Adsorption and Cell Adhesion by Photoresponsive GaN Nanowires.  

PubMed

Interfacing nanowires with living cells is attracting more and more interest due to the potential applications, such as cell culture engineering and drug delivery. We report on the feasibility of using photoresponsive semiconductor gallium nitride (GaN) nanowires (NWs) for regulating the behaviors of biomolecules and cells at the nano/biointerface. The GaN NWs have been fabricated by a facile chemical vapor deposition method. The superhydrophobicity to superhydrophilicity transition of the NWs is achieved by UV illumination. Bovine serum albumin adsorption could be modulated by photoresponsive GaN NWs. Tunable cell detachment and adhesion are also observed. The mechanism of the NW surface responsible for modulating both of protein adsorption and cell adhesion is discussed. These observations of the modulation effects on protein adsorption and cell adhesion by GaN NWs could provide a novel approach toward the regulation of the behaviors of biomolecules and cells at the nano/biointerface, which may be of considerable importance in the development of high-performance semiconductor nanowire-based biomedical devices for cell culture engineering, bioseparation, and diagnostics. PMID:24073887

Li, Jingying; Han, Qiusen; Zhang, Ying; Zhang, Wei; Dong, Mingdong; Besenbacher, Flemming; Yang, Rong; Wang, Chen

2013-09-27

224

Presence of laminin-binding proteins in trichomonads and their role in adhesion.  

PubMed

Adhesion is regarded as an important feature in the pathogenesis of various microorganisms. Ability to recognize extracellular matrix proteins, such as laminin or fibronectin, has been correlated with invasiveness. We report that laminin enhances the adhesion of the parasitic protozoa Trichomonas vaginalis and Tritrichomonas foetus to a polystyrene substrate and to the surface of epithelial cells (Madin-Darby canine kidney cell line) in vitro. The enhancement was higher for T. vaginalis than for T. foetus. Addition of anti-laminin antibodies to medium significantly inhibited the adhesion of parasites to polystyrene substrate. Indirect immunofluorescence and transmission electron microscopy of replicas of the parasite's surface labeled with antibody-gold complexes showed laminin-binding sites distributed over the parasite surface. Iodinated P1 fragment of laminin, which retains the laminin-binding site, binds saturably to the parasite surface with a Kd of 19.5 nM, for about 3 X 10(5) binding sites per cell. Immunoblotting analysis of whole parasite extracts showed that a protein of 118 kDa is responsible for laminin binding. PMID:2973059

Casta e Silva Filho, F; de Souza, W; Lopes, J D

1988-11-01

225

Presence of laminin-binding proteins in trichomonads and their role in adhesion.  

PubMed Central

Adhesion is regarded as an important feature in the pathogenesis of various microorganisms. Ability to recognize extracellular matrix proteins, such as laminin or fibronectin, has been correlated with invasiveness. We report that laminin enhances the adhesion of the parasitic protozoa Trichomonas vaginalis and Tritrichomonas foetus to a polystyrene substrate and to the surface of epithelial cells (Madin-Darby canine kidney cell line) in vitro. The enhancement was higher for T. vaginalis than for T. foetus. Addition of anti-laminin antibodies to medium significantly inhibited the adhesion of parasites to polystyrene substrate. Indirect immunofluorescence and transmission electron microscopy of replicas of the parasite's surface labeled with antibody-gold complexes showed laminin-binding sites distributed over the parasite surface. Iodinated P1 fragment of laminin, which retains the laminin-binding site, binds saturably to the parasite surface with a Kd of 19.5 nM, for about 3 X 10(5) binding sites per cell. Immunoblotting analysis of whole parasite extracts showed that a protein of 118 kDa is responsible for laminin binding. Images

Casta e Silva Filho, F; de Souza, W; Lopes, J D

1988-01-01

226

Reduction of Adhesion between Steel and Grilled Fish Protein with Ultra-Hydrophobic DLC  

NASA Astrophysics Data System (ADS)

There is an issue of the fish adhering to the metal grids of grill strongly after grilling fish. Recently, the temperature in a grill equipment is over 500 °C, Fluorine resin coating which has low adhesion property can not endurant at 500 °C. In order to overcome this issue, we proposed a new grill not to adhere a fish with Ultra-Hydrophobic Diamond-like Carbon coating named as UH-DLC coating. UH-DLC coating has high hydrophobicity. We expected this coating to decrease wettability of water including fish protein and contact area, because fish protein includes about 90% water. Contact angle of water on UH-DLC was over 120° at room temperature. After heating at 500 °C for 54 minutes, UH-DLC kept ultra-hydrophobic property. On the other hand, Fluorine resin coating desappeared hydrophobic properties after heating at 500 °C for 54 minutes. It was conducted adhesion test for UH-DLC coating, Fluorine resin coating and no coating grilling rods after the grilling of real fish in a grill equipment by gas. The adhesion force between UH-DLC coating grill rods and real fish was as half as that of no coating grill rods and as much as that of Fluorine resin grill rods. So, we believe that Ultra Hydrophobic Diamond-like Carbon coating has a possibility for the usage as new grilling grids at high temperature.

Honda, Naoko; Kajiya, Makoto; Jang, Young-Jun; Kousaka, Hiroyuki; Umehara, Noritsugu; Tokoroyama, Takayuki

227

Promyelocytic Leukemia (PML) Protein Plays Important Roles in Regulating Cell Adhesion, Morphology, Proliferation and Migration  

PubMed Central

PML protein plays important roles in regulating cellular homeostasis. It forms PML nuclear bodies (PML-NBs) that act like nuclear relay stations and participate in many cellular functions. In this study, we have examined the proteome of mouse embryonic fibroblasts (MEFs) derived from normal (PML+/+) and PML knockout (PML?/?) mice. The aim was to identify proteins that were differentially expressed when MEFs were incapable of producing PML. Using comparative proteomics, total protein were extracted from PML?/? and PML+/+ MEFs, resolved by two dimensional electrophoresis (2-DE) gels and the differentially expressed proteins identified by LC-ESI-MS/MS. Nine proteins (PML, NDRG1, CACYBP, CFL1, RSU1, TRIO, CTRO, ANXA4 and UBE2M) were determined to be down-regulated in PML?/? MEFs. In contrast, ten proteins (CIAPIN1, FAM50A, SUMO2 HSPB1 NSFL1C, PCBP2, YWHAG, STMN1, TPD52L2 and PDAP1) were found up-regulated. Many of these differentially expressed proteins play crucial roles in cell adhesion, migration, morphology and cytokinesis. The protein profiles explain why PML?/? and PML+/+ MEFs were morphologically different. In addition, we demonstrated PML?/? MEFs were less adhesive, proliferated more extensively and migrated significantly slower than PML+/+ MEFs. NDRG1, a protein that was down-regulated in PML?/? MEFs, was selected for further investigation. We determined that silencing NDRG1expression in PML+/+ MEFs increased cell proliferation and inhibited PML expression. Since NDRG expression was suppressed in PML?/? MEFs, this may explain why these cells proliferate more extensively than PML+/+ MEFs. Furthermore, silencing NDRG1expression also impaired TGF-?1 signaling by inhibiting SMAD3 phosphorylation.

Tang, Mei Kuen; Liang, Yong Jia; Chan, John Yeuk Hon; Wong, Sing Wan; Chen, Elve; Yao, Yao; Gan, Jingyi; Xiao, Lihai; Leung, Hin Cheung; Kung, Hsiang Fu; Wang, Hua; Lee, Kenneth Ka Ho

2013-01-01

228

High Affinity Neurexin Binding to Cell Adhesion G-protein-coupled Receptor CIRL1/Latrophilin-1 Produces an Intercellular Adhesion Complex*  

PubMed Central

The G-protein-coupled receptor CIRL1/latrophilin-1 (CL1) and the type-1 membrane proteins neurexins represent distinct neuronal cell adhesion molecules that exhibit no similarities except for one common function: both proteins are receptors for ?-latrotoxin, a component of black widow spider venom that induces massive neurotransmitter release at synapses. Unexpectedly, we have now identified a direct binding interaction between the extracellular domains of CL1 and neurexins that is regulated by alternative splicing of neurexins at splice site 4 (SS4). Using saturation binding assays, we showed that neurexins lacking an insert at SS4 bind to CL1 with nanomolar affinity, whereas neurexins containing an insert at SS4 are unable to bind. CL1 competed for neurexin binding with neuroligin-1, a well characterized neurexin ligand. The extracellular sequences of CL1 contain five domains (lectin, olfactomedin-like, serine/threonine-rich, hormone-binding, and G-protein-coupled receptor autoproteolysis-inducing (GAIN) domains). Of these domains, the olfactomedin-like domain mediates neurexin binding as shown by deletion mapping. Cell adhesion assays using cells expressing neurexins and CL1 revealed that their interaction produces a stable intercellular adhesion complex, indicating that their interaction can be trans-cellular. Thus, our data suggest that CL1 constitutes a novel ligand for neurexins that may be localized postsynaptically based on its well characterized interaction with intracellular SH3 and multiple ankyrin repeats adaptor proteins (SHANK) and could form a trans-synaptic complex with presynaptic neurexins.

Boucard, Antony A.; Ko, Jaewon; Sudhof, Thomas C.

2012-01-01

229

Mechanical Activation of a Multimeric Adhesive Protein Through Domain Conformational Change  

NASA Astrophysics Data System (ADS)

The mechanical force-induced activation of the adhesive protein von Willebrand factor (VWF), which experiences high hydrodynamic forces, is essential in initiating platelet adhesion. The importance of the mechanical force-induced functional change is manifested in the multimeric VWF’s crucial role in blood coagulation, when high fluid shear stress activates plasma VWF (PVWF) multimers to bind platelets. Here, we showed that a pathological level of high shear stress exposure of PVWF multimers results in domain conformational changes, and the subsequent shifts in the unfolding force allow us to use force as a marker to track the dynamic states of the multimeric VWF. We found that shear-activated PVWF multimers are more resistant to mechanical unfolding than nonsheared PVWF multimers, as indicated in the higher peak unfolding force. These results provide insight into the mechanism of shear-induced activation of PVWF multimers.

Wijeratne, Sithara S.; Botello, Eric; Yeh, Hui-Chun; Zhou, Zhou; Bergeron, Angela L.; Frey, Eric W.; Patel, Jay M.; Nolasco, Leticia; Turner, Nancy A.; Moake, Joel L.; Dong, Jing-fei; Kiang, Ching-Hwa

2013-03-01

230

Identification of heparin as a ligand for the A-domain of Plasmodium falciparum thrombospondin-related adhesion protein  

Microsoft Academic Search

Thrombospondin-related adhesion protein (TRAP) is a Plasmodium falciparum transmembrane protein that is expressed within the micronemes of sporozoites, and is implicated in host cell invasion and motility. Contained within the extracellular region of TRAP is an A-domain, a module found in a number of membrane, plasma and matrix proteins, that is often involved in ligand recognition. In order to determine

Christopher J. McCormick; Danny S. Tuckwell; Andrea Crisanti; Martin J. Humphries; Michael R. Hollingdale

1999-01-01

231

Adhesion, spreading, and proliferation of cells on protein carpets: effects of stability of a carpet.  

PubMed

In the present report we have investigated the role that the physical properties of substrata play in modulating the effects which components of extracellular matrix (ECM) exert on adhesion, spreading, and growth of retinal pigmented epithelial cells. By simple modifications of conditions for protein adsorption on glass we obtained a set of substrata all coated with proteins of ECM (protein carpets) but with different physical properties. Using these protein carpets we have shown that their stability (desorption rate) in tissue culture conditions varies according to the technique with which they were prepared. Both semiremovable and immobilized carpets are stable, whereas removable protein carpets desorb readily. Therefore, the protein concentration or composition or both may change with time in tissue culture depending on the technique used to prepare the carpet. In addition, efficacy of cell attachment to given protein may vary depending on whether a technique used to prepare the protein carpet involves denaturation of the protein. Adherent cells quickly remove (clear) weakly adsorbed protein carpets and it seems that the carpet removal is a mechanical process. During the carpet removal cells are rounded, which indicates that a spread cell phenotype normally associated with stress fibers and focal contacts occurs when the substratum is rigid enough to sustain cell traction. In addition, substrata lacking the rigidity to support the spread phenotype do not support cell proliferation either. PMID:1748628

Opas, M; Dziak, E

1991-11-01

232

Passive acquisition of leukocyte proteins is associated with changes in phosphorylation of cellular proteins and cell-cell adhesion properties.  

PubMed Central

In this report, we show that interaction of neoplastic epithelial cells with vesicles derived from leukocytes results in passive acquisition by tumor cells of a diverse group of leukocyte proteins. Vesicles shed from leukocytes were heterogeneous and exhibited the specific proteins expressed on leukocyte subsets. Accordingly, epithelial cells differentially acquired leukocyte proteins associated with vesicles. Ultrastructural localization demonstrated that acquired proteins were associated with the plasma membranes of the epithelial cells. The binding of tumor cells that passively acquired leukocyte proteins to immobilized intercellular adhesion molecule-1 and to endothelial cells was significantly increased. Furthermore, passive acquisition of proteins on the plasma membranes of epithelial cells was associated with modulation of overall phosphorylation of proteins in the range of 20-65 kd and consisted of both increased as well as decreased phosphorylation of specific protein species in the cells. These findings demonstrate that leukocyte proteins that are shed in association with vesicles passively coat the plasma membranes of target epithelial cells. Passive acquisition of proteins by cells modulates the constitutive properties endowed upon cells by their native plasma membranes and is associated with changes in phosphorylation of cell proteins. Images Figure 1 Figure 2 Figure 4 Figure 6

Tabibzadeh, S. S.; Kong, Q. F.; Kapur, S.

1994-01-01

233

Expression of E-Cadherin and N-Cadherin in Perinatal Hamster Ovary: Possible Involvement in Primordial Follicle Formation and Regulation by Follicle-Stimulating Hormone  

PubMed Central

We examined the expression and hormonal regulation of E-cadherin (CDH1) and N-cadherin (CDH2) with respect to primordial follicle formation. Hamster Cdh1 and Cdh2 cDNA and amino acid sequences were more than 90% similar to those of the mouse, rat, and human. Although CDH1 expression remained exclusively in the oocytes during neonatal ovary development, CDH2 expression shifted from the oocytes to granulosa cells of primordial follicles on postnatal day (P)8. Subsequently, strong CDH2 expression was restricted to granulosa cells of growing follicles. Cdh2 mRNA levels in the ovary decreased from embryonic d 13 through P10 with a transient increase on P7, which was the day before the appearance of primordial follicles. Cdh1 mRNA levels decreased from embryonic d 13 through P3 and then showed a transient increase on P8, coinciding with the formation of primordial follicles. CDH1 and CDH2 expression were consistent with that of mRNA. Neutralization of FSH in utero impaired primordial follicle formation with an associated decrease in Cdh2 mRNA and CDH2, but an increase in Cdh1 mRNA and CDH1 expression. The altered expression was reversed by equine chorionic gonadotropin treatment on P1. Whereas a CDH2 antibody significantly reduced the formation of primordial and primary follicles in vitro, a CDH1 antibody had the opposite effect. This is the first evidence to suggest that primordial follicle formation requires a differential spatiotemporal expression and action of CDH1 and CDH2. Further, FSH regulation of primordial follicle formation may involve the action of CDH1 and CDH2.

Wang, Cheng; Roy, Shyamal K.

2010-01-01

234

Differential Effect of Actomyosin Relaxation on the Dynamic Properties of Focal Adhesion Proteins  

PubMed Central

Treatment of cultured cells with inhibitors of actomyosin contractility induces rapid deterioration of stress fibers, and disassembly of the associated focal adhesions (FAs). In this study, we show that treatment with the Rho kinase inhibitor Y-27632, which blocks actomyosin contractility, induces disarray in the FA-associated actin bundles, followed by the differential dissociation of eight FA components from the adhesion sites. Live-cell microscopy indicated that the drug triggers rapid dissociation of VASP and zyxin from FAs (? values of 7-8 min), followed by talin, paxillin and ILK (? ~16 min), and then by FAK, vinculin and kindlin-2 (? = 25-28 min). Examination of the molecular kinetics of the various FA constituents, using Fluorescence Recovery After Photobleaching (FRAP), in the absence of or following short-term treatment with the drug, revealed major changes in the kon and koff values of the different proteins tested, which are in close agreement with their differential dissociation rates from the adhesion sites. These findings indicate that mechanical, actomyosin-generated forces differentially regulate the molecular kinetics of individual FA-associated molecules, and thereby modulate FA composition and stability.

Lavelin, Irena; Wolfenson, Haguy; Patla, Israel; Henis, Yoav I.; Medalia, Ohad; Volberg, Tova; Livne, Ariel; Kam, Zvi; Geiger, Benjamin

2013-01-01

235

TiO2 nanotubes functionalized with regions of bone morphogenetic protein-2 increases osteoblast adhesion.  

PubMed

Titanium (Ti) and its alloys are widely used in orthopedic and dental applications. However, the native TiO2 layer is not bioactive enough to form a direct bond with bone, which sometimes translates into a lack of osseointegration into juxtaposed bone that might lead to long term implant failure. In this study, the 20 amino acid peptide sequence (the so-called "knuckle epitope") of bone morphogenetic protein-2 (BMP-2) was immobilized onto Ti nanotubes created by electrochemical anodization. Further, human osteoblast (bone-forming cell) responses to such anodic Ti oxides functionalized with the BMP-2 knuckle epitope was examined in vitro. Materials were characterized by scanning electron and atomic force microscopy. Results of this in vitro study continued to provide evidence of increased osteoblast adhesion on Ti anodized to possess nanotubes compared to unanodized Ti. However, for the first time, results also showed that the immobilization of the BMP-2 knuckle epitope onto Ti anodized to possess nanotubes increased osteoblast adhesion compared to non-functionalized anodized Ti, anodized Ti functionalized with amine (NH2) groups, and unanodized Ti after 4 h. Results also showed increased osteoblast adhesion on amine terminated anodized Ti compared to respective non-functionalized anodized Ti and unanodized Ti. In summary, results of this in vitro study provided evidence that Ti anodized to possess nanotubes and then further functionalized with the BMP-2 knuckle epitope should be further studied for improved orthopedic applications. PMID:17618492

Balasundaram, Ganesan; Yao, Chang; Webster, Thomas J

2008-02-01

236

Platelet adhesion and plasma protein adsorption control of collagen surfaces by He+ ion implantation  

NASA Astrophysics Data System (ADS)

He+ ion implanted collagen-coated tubes with a fluence of 1×1014 ions/cm2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He+ ion implanted collagen with a fluence of 1×1014 ions/cm2. Platelet adhesion (using platelet rich plasma) was inhibited on the He+ ion implanted collagen with a fluence of 1×1014 ions/cm2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1×1013, 1×1015 and 1×1016 ions/cm2. Platelet activation with washed platelets was observed on untreated collagen and He+ ion implanted collagen with a fluence of 1×1014 ions/cm2 and was inhibited with fluences of 1×1013, 1×1015 and 1×1016 ions/cm2. Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He+ ion implanted collagen over a fluence of 1×1013 ions/cm2. On the 1×1014 ions/cm2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He+ ion implanted collagen with a fluence of 1×1014 ions/cm2 and that plasma protein adsorption took an important role repairing the graft surface.

Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

2003-05-01

237

Understanding Marine Mussel Adhesion  

SciTech Connect

In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production, and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability of recombinant mussel adhesive proteins will enable researchers to formulate adhesives that are waterimpervious and ecologically safe and can bind materials ranging from glass, plastics, metals, and wood to materials, such as bone or teeth, biological organisms, and other chemicals or molecules. Unfortunately, as of yet scientists have been unable to duplicate the processes that marine mussels use to create adhesive structures. This study provides a background on adhesive proteins identified in the blue mussel, Mytilus edulis, and introduces our research interests and discusses the future for continued research related to mussel adhesion.

H. G. Silverman; F. F. Roberto

2007-12-01

238

Effects of High Forces on Integrin-Mediated Adhesion Protein Complexes in Fibroblast Cells  

NASA Astrophysics Data System (ADS)

Magnetic tweezers were designed and used to generate large forces on ferrous beads bound to the surface of adherent fibroblasts. Cells sense and exert forces on the extracellular matrix via integrins, a family of transmembrane receptors. On the cytoplasm end, the signaling from the integrins to the cytoskeleton is mediated by a complex of proteins, which were fluorescently tagged, and tracked in live cells. The magnetic beads were functionalized with a fibronectin construct designed to enhance the spatial efficiency of the integrin binding domain FNIII7-10. Rapid protein reorganization was observed in response to modulated forces applied in the lamella region. This allowed for tracking of the spatial and temporal response of proteins involved in the adhesion pathways.

Tanase, Monica

2005-03-01

239

Heparin functionalized PEG gels that modulate protein adsorption for hMSC adhesion and differentiation.  

PubMed

Heparin was modified with methacrylate groups, copolymerized with dimethacrylated poly(ethylene glycol), and analyzed as a localized delivery vehicle for bFGF and synthetic extracellular matrix for the differentiation of hMSCs. By deriving cues from molecules normally present in the extracellular matrix (ECM), a complex network of collagens, laminin, fibronectin, glycosaminoglycans, and growth factors, synthetic cell scaffolds can be designed that actively sequester important bioactive signals. Among the glycosaminoglycans, heparin binds reversibly with many proteins, therefore, poly(ethylene glycol) based biomaterials, normally resistant to cell adhesion, functionalized with heparin in order to sequester important proteins, can actively and selectively stimulate desired cell functions. Results demonstrate that methacrylate-modified heparin retained its ability to bind heparin-binding proteins both in solution and when copolymerized with dimethacrylated PEG in a hydrogel. In addition, the heparin functionalized gels can deliver biologically active bFGF for up to 5 weeks. Finally, the gels were examined as a potential scaffold for hMSC culture and were found to promote adhesion, proliferation, and osteogenic differentiation. PMID:16701827

Benoit, Danielle S W; Anseth, Kristi S

2005-04-26

240

The endocytic protein GRAF1 is directed to cell-matrix adhesion sites and regulates cell spreading  

PubMed Central

The rho GTPase-activating protein GTPase regulator associated with focal adhesion kinase-1 (GRAF1) remodels membranes into tubulovesicular clathrin-independent carriers (CLICs) mediating lipid-anchored receptor endocytosis. However, the cell biological functions of this highly prevalent endocytic pathway are unclear. In this article, we present biochemical and cell biological evidence that GRAF1 interacted with a network of endocytic and adhesion proteins and was found enriched at podosome-like adhesions and src-induced podosomes. We further demonstrate that these sites comprise microdomains of highly ordered lipid enriched in GRAF1 endocytic cargo. GRAF1 activity was upregulated in spreading cells and uptake via CLICs was concentrated at the leading edge of migrating cells. Depletion of GRAF1, which inhibits CLIC generation, resulted in profound defects in cell spreading and migration. We propose that GRAF1 remodels membrane microdomains at adhesion sites into endocytic carriers, facilitating membrane turnover during cell morphological changes.

Doherty, Gary J.; Ahlund, Monika K.; Howes, Mark T.; Moren, Bjorn; Parton, Robert G.; McMahon, Harvey T.; Lundmark, Richard

2011-01-01

241

The species-specific egg receptor for sea urchin sperm adhesion is EBR1,a novel ADAMTS protein  

Microsoft Academic Search

Species-specific adhesion of sperm to the egg during sea urchin fertilization involves the interaction of the sperm adhesive protein,bindin,and a complementary receptor on the egg surface,and serves to restrict the gene pool to individuals of the same species. We used PCR represen- tation difference analysis to clone the species-specific egg receptor for bindin,EBR1,from Strongylocentrotus franciscanus (Sf) and S. purpuratus (Sp).

Noriko Kamei; Charles G. Glabe

2003-01-01

242

Erythroid developmental agglutinin is a protein lectin mediating specific cell-cell adhesion between differentiating rabbit erythroblasts  

Microsoft Academic Search

In many developmental systems beta-galactoside-specific protein lectins have been identified as components which appear at the cell surface in concert with an initial requirement for cell-cell adhesion during tissue formation1-8. Although some of these lectins have been purified, there has been little direct evidence concerning their role in establishing specific cell-cell contact. A mammalian system where selective cell-cell adhesion is

F. Lynne Harrison; C. James Chesterton

1980-01-01

243

Micropatterned substrates coated with neuronal adhesion molecules for high-content study of synapse formation.  

PubMed

Studying the roles of different proteins and the mechanisms involved in synaptogenesis is hindered by the complexity and heterogeneity of synapse types, and by the spatial and temporal unpredictability of spontaneous synapse formation. Here we demonstrate a robust and high-content method to induce selectively presynaptic or postsynaptic structures at controlled locations. Neurons are cultured on micropatterned substrates comprising arrays of micron-scale dots coated with various synaptogenic adhesion molecules. When plated on neurexin-1?-coated micropatterns, neurons expressing neuroligin-1 exhibit specific dendritic organization and selective recruitment of the postsynaptic scaffolding molecule PSD-95. Furthermore, functional AMPA receptors are trapped at neurexin-1? dots, as revealed by live-imaging experiments. In contrast, neurons plated on SynCAM1-coated substrates exhibit strongly patterned axons and selectively assemble functional presynapses. N-cadherin coating, however, is not able to elicit synapses, indicating the specificity of our system. This method opens the way to both fundamental and therapeutic studies of various synaptic systems. PMID:23934334

Czöndör, Katalin; Garcia, Mikael; Argento, Amélie; Constals, Audrey; Breillat, Christelle; Tessier, Béatrice; Thoumine, Olivier

2013-01-01

244

Adhesion proteins increase cellular attachment, follicle-stimulating hormone receptors, and progesterone production in cultured porcine granulosa cells.  

PubMed

We sought to determine the influence of different constituents of the extracellular matrix on porcine granulosa cell function by assessing cellular attachment, cellular morphology, follicle-stimulating hormone (FSH) receptors, and progesterone production. Cells from immature porcine ovarian follicles were cultured for up to 6 days in serum-free medium containing porcine FSH (pFSH, 10 ng/ml) in culture dishes either uncoated or coated with one of the following adhesion proteins: gelatin (1 mg/cm2), fibronectin (1 microgram/cm2), laminin (1 microgram/cm2), type I collagen (10 micrograms/cm2), or type IV collagen (7.8 micrograms/cm2). Fibronectin, laminin, type I collagen, and type IV collagen increased cellular attachment significantly (P < 0.05). All adhesion proteins except gelatin influenced cellular morphology. Cells cultured on laminin or type IV collagen formed dense clusters of rounded cells. Cells cultured in dishes coated with each adhesion protein except gelatin had higher 125I-pFSH binding per cell than cells cultured in uncoated dishes, with increases of 7- to 12-fold over control (P < 0.05). All adhesion proteins increased progesterone production, ranging from 10- to 50-fold over control (P < 0.05). In summary, not only did adhesion proteins increase attachment to the dishes but they also increased FSH receptors and differentiated function (progesterone production) of granulosa cells from immature porcine ovarian follicles. PMID:8618955

Sites, C K; Kessel, B; LaBarbera, A R

1996-05-01

245

The muscle integrin binding protein (MIBP) interacts with ?7?1 integrin and regulates cell adhesion and laminin matrix deposition  

Microsoft Academic Search

Integrins are ?? transmembrane receptors that function in key cellular processes, including cell adhesion, differentiation, and extracellular matrix deposition through interactions with extracellular, membrane, and cytoplasmic proteins. We previously identified and cloned a muscle ?1 integrin cytoplasmic binding protein termed MIBP and found that the expression level of MIBP is critical in the decision-making process of terminal myogenic differentiation. We

Ji Li; Hongwei Rao; Dean Burkin; Stephen J Kaufman; Chuanyue Wu

2003-01-01

246

A mutant form of the rho protein can restore stress fibers and adhesion plaques in v-src transformed fibroblasts  

Microsoft Academic Search

The organization of polymerized actin in the mammalian cell is regulated by several members of the rho family. Three rho proteins, cdc42, rac and rho act in a cascade to organize the intracellular actin cytoskeleton. Rho proteins are involved in the formation of actin stress fibers and adhesion plaques in fibroblasts. During transformation of mammalian cells by oncogenes the cytoskeleton

Thomas Mayer; Markus Meyer; Annette Janning; Anke C Schiedel; Angelika Barnekow

1999-01-01

247

Regulation of Bacteria-Induced Intercellular Adhesion Molecule-1 by CCAAT/Enhancer Binding Proteins  

PubMed Central

Direct interaction between bacteria and epithelial cells may initiate or amplify the airway response through induction of epithelial defense gene expression by nuclear factor-?B (NF-?B). However, multiple signaling pathways modify NF-?B effects to modulate gene expression. In this study, the effects of CCAAT/enhancer binding protein (C/EBP) family members on induction of the leukocyte adhesion glycoprotein intercellular adhesion molecule-1 (ICAM-1) was examined in primary cultures of human tracheobronchial epithelial cells incubated with nontypeable Haemophilus influenzae. Increased ICAM-1 gene transcription in response to H. influenzae required gene sequences located at ?200 to ?135 in the 5?-flanking region that contain a C/EBP-binding sequence immediately upstream of the NF-?B enhancer site. Constitutive C/EBP? was found to have an important role in epithelial cell ICAM-1 regulation, while the adjacent NF-?B sequence binds the RelA/p65 and NF-?B1/p50 members of the NF-?B family to induce ICAM-1 expression in response to H. influenzae. The expression of C/EBP proteins is not regulated by p38 mitogen-activated protein kinase activation, but p38 affects gene transcription by increasing the binding of TATA-binding protein to TATA-box–containing gene sequences. Epithelial cell ICAM-1 expression in response to H. influenzae was decreased by expressing dominant-negative protein or RNA interference against C/EBP?, confirming its role in ICAM-1 regulation. Although airway epithelial cells express multiple constitutive and inducible C/EBP family members that bind C/EBP sequences, the results indicate that C/EBP? plays a central role in modulation of NF-?B–dependent defense gene expression in human airway epithelial cells after exposure to H. influenzae.

Manzel, Lori J.; Chin, Cecilia L.; Behlke, Mark A.; Look, Dwight C.

2009-01-01

248

Loss of intercellular adhesion activates a transition from low- to high-grade human squamous cell carcinoma.  

PubMed

The relationship between loss of intercellular adhesion and the biologic properties of human squamous cell carcinoma is not well understood. We investigated how abrogation of E-cadherin-mediated adhesion influenced the behavior and phenotype of squamous cell carcinoma in 3D human tissues. Cell-cell adhesion was disrupted in early-stage epithelial tumor cells (HaCaT-II-4) through expression of a dominant-negative form of E-cadherin (H-2Kd-Ecad). Three-dimensional human tissue constructs harboring either H-2Kd-Ecad-expressing or control II-4 cells (pBabe, H-2Kd-EcadDeltaC25) were cultured at an air-liquid interface for 8 days and transplanted to nude mice; tumor phenotype was analyzed 2 days and 2 and 4 weeks later. H-2Kd-Ecad-expressing tumors demonstrated a switch to a high-grade aggressive tumor phenotype characterized by poorly differentiated tumor cells that infiltrated throughout the stroma. This high-grade carcinoma revealed elevated cell proliferation in a random pattern, loss of keratin 1 and diffuse deposition of laminin 5 gamma2 chain. When II-4 cell variants were seeded into type I collagen gels as an in vitro assay for cell migration, we found that only E-cadherin-deficient cells detached, migrated as single cells and expressed N-cadherin. Function-blocking studies demonstrated that this migration was matrix metalloproteinase-dependent, as GM-6001 and TIMP-2, but not TIMP-1, could block migration. Gene expression profiles revealed that E-cadherin-deficient II-4 cells demonstrated increased expression of proteases and cell-cell and cell-matrix proteins. These findings showed that loss of E-cadherin-mediated adhesion plays a causal role in the transition from low- to high-grade squamous cell carcinomas and that the absence of E-cadherin is an important prognostic marker in the progression of this disease. PMID:16152579

Margulis, Alexander; Zhang, Weitian; Alt-Holland, Addy; Pawagi, Sujata; Prabhu, Padmaja; Cao, Jian; Zucker, Stanley; Pfeiffer, Laurence; Garfield, Jacqueline; Fusenig, Norbert E; Garlick, Jonathan A

2006-02-15

249

Crystal structure of the human vascular adhesion protein-1: Unique structural features with functional implications  

PubMed Central

The expression of human vascular adhesion protein-1 (hVAP-1) is induced at sites of inflammation where extravasation of lymphocytes from blood to the peripheral tissue occurs. We have solved the X-ray structure of hVAP-1, a human copper amine oxidase (CAO), which is distinguished from other CAOs in being membrane-bound. The dimer structure reveals some intriguing features that may have fundamental roles in the adhesive and enzymatic functions of hVAP-1, especially regarding the role of hVAP-1 in inflammation, lymphocyte attachment, and signaling. Firstly, Leu469 at the substrate channel may play a key role in controlling the substrate entry; depending on its conformation, it either blocks or gives access to the active site. Secondly, sugar units are clearly observed at two of the six predicted N-glycosylation sites. Moreover, mutagenesis analysis showed that all of the predicted sites were glycosylated in the protein used for crystallization. Thirdly, the existence of a solvent-exposed RGD motif at the entrance to each active site in hVAP-1 suggests that it may have a functional role.

Airenne, Tomi T.; Nymalm, Yvonne; Kidron, Heidi; Smith, David J.; Pihlavisto, Marjo; Salmi, Marko; Jalkanen, Sirpa; Johnson, Mark S.; Salminen, Tiina A.

2005-01-01

250

Yin yang-1 regulates the characterized murine focal adhesion-associated protein promoter.  

PubMed

The focal adhesion-associated protein (FAAP), product of the murine D10Wsu52e gene, is involved in modulating cell adhesion dynamics. The ubiquitously expressed protein belongs to the highly conserved UPF0027 family, the newly identified RNA >p ligase family. To understand the mechanisms underlying FAAP expression and regulation, we first mapped its major transcription start site at the nucleotide 79? bp upstream of the ATG codon. The murine FAAP 2.1? kb 5'-flanking region was cloned, analyzed, and aligned with the corresponding 1.7? kb region of its human homolog HSPC117. Despite the differences in activity, cell in vitro transfection and testis in vivo electroporation identified a 0.2 kb efficient promoter region lacking a functional TATA-box. Gel shift assays confirmed the specific interaction between Yin Yang-1 (YY1) and the potential element in the proximal region of the FAAP promoter. Site mutation, truncation, RNAi, and overexpression analyses suggested that YY1 is an important regulator of the FAAP promoter. PMID:21977911

Ding, Nai-Zheng; He, Mei; He, Cheng-Qiang; Hu, Jin-Song; Teng, Jun-Lin; Chen, Jianguo

2011-10-06

251

Augmenting the articular cartilage-implant interface: functionalizing with a collagen adhesion protein  

PubMed Central

The lack of integration between implants and articular cartilage is an unsolved problem that negatively impacts the development of treatments for focal cartilage defects. Many approaches attempt to increase the number of matrix-producing cells that can migrate to the interface, which may help to reinforce the boundary over time but does not address the problems associated with an initially unstable interface. The objective of this study was to develop a bio-adhesive implant to create an immediate bond with the extracellular matrix components of articular cartilage. We hypothesized that implant-bound CollageN Adhesion protein, CNA, would increase the interfacial strength between a poly(vinly alcohol), PVA, implant and articular cartilage immediately after implantation, without preventing cell migration into the implant. By way of a series of in vitro immunohistochemical and mechanical experiments, we demonstrated that: free CNA can bind to articular cartilage, implant-bound CNA can bind to collagen type II and that implants functionalized with CNA result in a four-fold increase in interfacial strength with cartilage relative to un-treated implants at day zero. Of note, the interfacial strength significantly decreased after 21 days in culture which may be an indication that the protein itself has lost its effectiveness. Our data suggests that functionalizing scaffolds with CNA may be a viable approach towards creating an initially stable interface between scaffolds and articular cartilage. Further efforts are required to ensure long-term interface stability.

Allon, A.A.; Ng, K.W.; Hammoud, S.; Russell, B.H.; Jones, C.M.; Rivera, J.J.; Schwartz, J.; Hook, M.; Maher, S.A.

2012-01-01

252

Bacterial adhesion to animal tissues: protein determinants for recognition of extracellular matrix components.  

PubMed

The extracellular matrix (ECM) is present within all animal tissues and organs. Actually, it surrounds the eukaryotic cells composing the four basic tissue types, i.e. epithelial, muscle, nerve and connective. ECM does not solely refer to connective tissue but composes all tissues where its composition, structure and organization vary from one tissue to another. Constituted of the four main fibrous proteins, i.e. collagen, fibronectin, laminin and elastin, ECM components form a highly structured and functional network via specific interactions. From the basement membrane to interstitial matrix, further heterogeneity exists in the organization of the ECM in various tissues and organs also depending on their physiological state. Back to a molecular level, bacterial proteins represent the most significant part of the microbial surface components recognizing adhesive matrix molecules (MSCRAMM). These cell surface proteins are secreted and localized differently in monoderm and diderm-LPS bacteria. While one collagen-binding domain (CBD) and different fibronectin-binding domains (FBD1 to 8) have been registered in databases, much remains to be learned on specific binding to other ECM proteins via single or supramolecular protein structures. Besides theinteraction of bacterial proteins with individual ECM components, this review aims at stressing the importance of fully considering the ECM at supramolecular, cellular, tissue and organ levels. This conceptual view should not be overlooked to rigorously comprehend the physiology of bacterial interaction from commensal to pathogenic species. PMID:22882798

Chagnot, Caroline; Listrat, Anne; Astruc, Thierry; Desvaux, Mickaël

2012-09-03

253

Altered type I protein kinase in adhesion defective CHO cell variants  

SciTech Connect

AD/sup v/ cells are Chinese hamster ovary (CHO) cell variants which cannot adhere to fibronectin coated substrata. The authors have shown that the defect in some clones of AD/sup v/ cells is distal to the initial interaction between fibronectin and its cell surface receptors, and that it extends to fibronectin medicated aggregation and endocytosis. The adhesion defect in some AD/sup v/ clones can be corrected by raising intracellular cAMP levels. Here they examine the protein kinase activities and phosphorylation patterns in an adhesion defective variant clone AD/sup v/F11CA11. Analysis of the cAMP dependent protein kinase activity (cAdPK) in crude extracts of F11CA11 cells shows an apparent increase in K (activation) as compared to wild type (WT) CHO cell extracts. Binding studies with /sup 3/H-cAMP reveal that the type I peak in F11CA11 has a K/sub d/ of 1.7 x 10/sup 08/ M as compared to 2.0 x 10/sup 09/ M for WT, whereas the type II peak K/sub d/ is approximately 1 x 10 /sup 09/ M for both WT and F11CA11. Two-dimensional polyacrylamide gel analysis of /sup 32/Pi labeled WT cells and F11CA11 cells with or without cAMP treatment reveals the presence of a protein(s) of 50 kilodaltons which is phosphorylated in WT cells and in cAMP treated F11CA11 cells but not in untreated F11CA11 cells. These findings, coupled with previous observations, strongly indicate that the adhesion defect in AD/sup v/F11CA11 cells is associated with an altered type I cAdPK having lower affinity for cAMP. At normal cellular cAMP levels this enzyme fails to phosphorylate one or more critical protein substrates; however, by raising internal cAMP levels, the defect can be overcome.

Cheung, E.; Brown, P.J.; Juliano, R.L.

1987-01-01

254

Role of protein kinase activation in the induction of B cell adhesion by MHC class II ligands.  

PubMed

Engagement of MHC class II (Ia) molecules on B cells induces tyrosine phosphorylation, phosphoinositide turnover, elevation of intracellular calcium concentrations, and a rise in cAMP levels. However, a role for these biochemical signals in mediating functional responses induced by Ia ligands remains largely undefined. In this study, we utilized the induction of B cell adhesion by Ia ligands to demonstrate a role for signals transduced via Ia molecules in the generation of a functional response. Ia ligands that induced B cell aggregation induced tyrosine phosphorylation, whereas Ia ligands that did not induce B cell aggregation failed to induce any detectable tyrosine phosphorylation. Ia-induced B cell aggregation and tyrosine phosphorylation were inhibited by genistein and by herbimycin A, inhibitors of tyrosine kinases (PTK). Sphingosine and calphostin C, inhibitors of protein kinase C (PKC), also inhibited Ia-induced adhesion whereas HA1004, an inhibitor of cyclic nucleotide-dependent kinases, did not. Ia ligands induced both LFA-1-dependent and LFA-1-independent B cell adhesion. These two pathways of cell adhesion differed in their requirement for activation signals. PKC activation was sufficient for LFA-1-dependent adhesion, whereas LFA-1-independent adhesion required independent phosphorylation events mediated by PKC and by PTK. These results provide functional relevance for biochemical signals transduced via Ia molecules by demonstrating that Ia-induced B cell adhesion is mediated by the activation of PKC and by one or more PTK. PMID:1517559

Fuleihan, R; Spertini, F; Geha, R S; Chatila, T

1992-09-15

255

Spatiotemporal segregation of endothelial cell integrin and nonintegrin extracellular matrix-binding proteins during adhesion events  

PubMed Central

Bovine aortic endothelial cell (BAEC) attachments to laminin, fibronectin, and fibrinogen are inhibited by soluble arginine-glycine- aspartate (RGD)-containing peptides, and YGRGDSP activity is responsive to titration of either soluble peptide or matrix protein. To assess the presence of RGD-dependent receptors, immunoprecipitation and immunoblotting studies were conducted and demonstrated integrin beta 1, beta 3, and associated alpha subunits as well as a beta 1 precursor. Immunofluorescence of BAECs plated on laminin, fibronectin, and fibrinogen reveals different matrix-binding specificities of each of these integrin subclasses. By 1 h after plating, organization of beta 1 integrin into fibrillar streaks is influenced by laminin and fibronectin, whereas beta 3 integrin punctate organization is influenced by fibrinogen and the integrin spatial distribution changes with time in culture. In contrast, the nonintegrin laminin-binding protein LB69 only organizes after cell-substrate contact is well established several hours after plating. Migration of BAECs is also mediated by both integrin and nonintegrin matrix-binding proteins. Specifically, BAEC migration on laminin is remarkably sensitive to RGD peptide inhibition, and, in its presence, beta 1 integrin organization dissipates and reorganizes into perinuclear vesicles. However, RGD peptides do not alter LB69 linear organization during migration. Similarly, agents that block LB69--e.g., antibodies to LB69 as well as YIGSR-NH2 peptide--do not inhibit attachment of nonmotile BAECs to laminin. However, both anti-LB69 and YIGSR-NH2 inhibit late adhesive events such as spreading. Accordingly, we propose that integrin and nonintegrin extracellular matrix-binding protein organizations in BAECs are both temporally and spatially segregated during attachment processes. High affinity nonintegrin interaction with matrix may create necessary stable contacts for longterm attachment, while lower affinity integrins may be important for initial cell adhesion as well as for transient contacts of motile BAECs.

1990-01-01

256

Platelet adhesion and protein adsorption on silicone rubber surface by ozone-induced grafted polymerization with carboxybetaine monomer.  

PubMed

Platelet adhesion and protein adsorption on the silicone rubber film grafted with N,N'-dimethyl-N-methacryloyloxyethyl-N-(2-carboxyethyl) ammonium (DMMCA) was studied. The grafting was carried out by means of ozone-induced method and was confirmed by ATR-FTIR and XPS investigations. The grafted films possessed relatively hydrophilic surface revealed by contact angle measurement. The blood compatibility of the grafted film was evaluated in vitro by platelet adhesion in platelet-rich plasma (PRP) and protein absorption in bovine fibrinogen (BFG) using silicone film as the reference. No substantial platelet adhesion was observed for the grafted films incubated in PRP for 60 and 180 min. The protein absorption was also significantly reduced after incubated in bovine fibrinogen for 60 min. Both the results indicated that the blood compatibility of silicone rubber was greatly improved by ozone-induced grafting of carboxybetaine zwitterionic polymer onto its surface. PMID:15698757

Zhou, Jun; Yuan, Jiang; Zang, Xiaopeng; Shen, Jian; Lin, Sicong

2005-03-10

257

The Desmosomal Armadillo Protein Plakoglobin Regulates Prostate Cancer Cell Adhesion and Motility through Vitronectin-Dependent Src Signaling  

PubMed Central

Plakoglobin (PG) is an armadillo protein that associates with both classic and desmosomal cadherins, but is primarily concentrated in mature desmosomes in epithelia. While reduced levels of PG have been reported in localized and hormone refractory prostate tumors, the functional significance of these changes is unknown. Here we report that PG expression is reduced in samples of a prostate tumor tissue array and inversely correlated with advancing tumor potential in 7 PCa cell lines. Ectopically expressed PG enhanced intercellular adhesive strength, and attenuated the motility and invasion of aggressive cell lines, whereas silencing PG in less tumorigenic cells had the opposite effect. PG also regulated cell-substrate adhesion and motility through extracellular matrix (ECM)-dependent inhibition of Src kinase, suggesting that PG’s effects were not due solely to increased intercellular adhesion. PG silencing resulted in elevated levels of the ECM protein vitronectin (VN), and exposing PG-expressing cells to VN induced Src activity. Furthermore, increased VN levels and Src activation correlated with diminished expression of PG in patient tissues. Thus, PG may inhibit Src by keeping VN low. Our results suggest that loss of intercellular adhesion due to reduced PG expression might be exacerbated by activation of Src through a PG-dependent mechanism. Furthermore, PG down-regulation during PCa progression could contribute to the known VN-dependent promotion of PCa invasion and metastasis, demonstrating a novel functional interaction between desmosomal cell-cell adhesion and cell-substrate adhesion signaling axes in prostate cancer.

Desai, Bhushan V.; Mirzoeva, Salida; Yang, Ximing J.; Green, Kathleen J.; Pelling, Jill C.

2012-01-01

258

Vasoconstrictor-induced endocytic recycling regulates focal adhesion protein localization and function in vascular smooth muscle.  

PubMed

Turnover of focal adhesions (FAs) is known to be critical for cell migration and adhesion of proliferative vascular smooth muscle (VSM) cells. However, it is often assumed that FAs in nonmigratory, differentiated VSM (dVSM) cells embedded in the wall of healthy blood vessels are stable structures. Recent work has demonstrated agonist-induced actin polymerization and Src-dependent FA phosphorylation in dVSM cells, suggesting that agonist-induced FA remodeling occurs. However, the mechanisms and extent of FA remodeling are largely unknown in dVSM. Here we show, for the first time, that a distinct subpopulation of dVSM FA proteins, but not the entire FA, remodels in response to the ?-agonist phenylephrine. Vasodilator-stimulated phosphoprotein and zyxin displayed the largest redistributions, while ?-integrin and FA kinase showed undetectable redistribution. Vinculin, metavinculin, Src, Crk-associated substrate, and paxillin displayed intermediate degrees of redistribution. Redistributions into membrane fractions were especially prominent, suggesting endosomal mechanisms. Deconvolution microscopy, quantitative colocalization analysis, and Duolink proximity ligation assays revealed that phenylephrine increases the association of FA proteins with early endosomal markers Rab5 and early endosomal antigen 1. Endosomal disruption with the small-molecule inhibitor primaquine inhibits agonist-induced redistribution of FA proteins, confirming endosomal recycling. FA recycling was also inhibited by cytochalasin D, latrunculin B, and colchicine, indicating that the redistribution is actin- and microtubule-dependent. Furthermore, inhibition of endosomal recycling causes a significant inhibition of the rate of development of agonist-induced dVSM contractions. Thus these studies are consistent with the concept that FAs in dVSM cells, embedded in the wall of the aorta, remodel during the action of a vasoconstrictor. PMID:23703522

Poythress, Ransom H; Gallant, Cynthia; Vetterkind, Susanne; Morgan, Kathleen G

2013-05-22

259

Blockade of Vascular Adhesion Protein-1 Inhibits Lymphocyte Infiltration in Rat Liver Allograft Rejection  

PubMed Central

Vascular adhesion protein-1 (VAP-1) has been shown to mediate lymphocyte adhesion to endothelia at sites of inflammation, but its functional role in vivo has not been tested in any rodent model. Here we report the effects of VAP-1 blockade on rat liver allograft rejection. BN recipients of PVG liver allografts (known to develop acute rejection by day 7) were treated with 2 mg/kg anti-VAP-1 (a new anti-rat VAP-1 mAb 174–5) or isotype-matched irrelevant antibody (NS1) every other day (n = 6/group) and one group with anti-VAP-1 2 mg/kg daily (n = 7). On day 7, samples were collected for transplant aspiration cytology, histology, and immunohistochemistry. Lymphocyte infiltration to the graft was clearly affected by VAP-blockade. The total inflammation, mainly the number of active lymphoid cells, in transplant aspiration cytology was significantly decreased in animals treated with anti-VAP-1 (4.7 ± 1.0 and 2.4 ± 1.0 corrected increment units, respectively) compared to control (6.6 ± 1.0) (P < 0.05). In histology, the intensity of portal inflammation was significantly decreased (P < 0.05). The amount of T cells expressing activation markers diminished. This is the first demonstration in any prolonged in vivo model that VAP-1 plays an important role in lymphocyte infiltration to sites of inflammation, and, in particular, liver allograft rejection.

Martelius, Timi; Salaspuro, Ville; Salmi, Marko; Krogerus, Leena; Hockerstedt, Krister; Jalkanen, Sirpa; Lautenschlager, Irmeli

2004-01-01

260

Calcium- and integrin-binding protein 1 regulates megakaryocyte ploidy, adhesion, and migration  

PubMed Central

Megakaryocytes are large, polyploid cells that produce platelets. We have previously reported that calcium- and integrin-binding protein 1 (CIB1) regulates endomitosis in Dami cells. To further characterize the role of CIB1 in megakaryopoiesis, we used a Cib1?/? mouse model. Cib1?/? mice have more platelets and BM megakaryocytes than wild-type (WT) controls (P < .05). Furthermore, subsequent analysis of megakaryocyte-CFU production revealed an increase with Cib1 deletion compared with WT (P < .05). In addition, BM from Cib1?/? mice, cultured with thrombopoietin (TPO) for 24 hours, produced more highly polyploid megakaryocytes than WT BM (P < .05). Subsequent analysis of TPO signaling revealed enhanced Akt and ERK1/2 phosphorylation, whereas FAKY925 phosphorylation was reduced in Cib1?/? megakaryocytes treated with TPO. Conversely, platelet recovery in Cib1?/? mice after platelet depletion was attenuated compared with WT (P < .05). This could be the result of impaired adhesion and migration, as adhesion to fibrinogen and fibronectin and migration toward an SDF-1? gradient were reduced in Cib1?/? megakaryocytes compared with WT (P < .05). In addition, Cib1?/? megakaryocytes formed fewer proplatelets compared with WT (P < .05), when plated on fibrinogen. These data suggest that CIB1 plays a dual role in megakaryopoiesis, initially by negatively regulating TPO signaling and later by augmenting proplatelet production.

Kostyak, John C.; Naik, Meghna U.

2012-01-01

261

Serum lipid profile in psoriatic patients: correlation between vascular adhesion protein 1 and lipoprotein (a).  

PubMed

Psoriasis is a chronic inflammatory skin disease characterized by excessive cellular replication. Apolipoproteins are genetically determined molecule whose role has been implied in cardiovascular pathology. Vascular adhesion protein-1 (VAP-1) is an adhesion molecule with an enzymatic activity that partakes in the migration process of lymphocytes into sites of inflammation. Our purpose was to evaluate the plasma lipid profiles, apolipoproteins (A1, B) and Lp (a) and VAP-1 in order to compare the lipid profile in psoriatic patients with non-affected persons and correlation between VAP-1 and Lp (a). We determined serum concentrations of lipids, lipoproteins , apolipoproteins and VAP-1 in 90 patients with psoriasis and 90 age matched controls. Serum Lp (a), apo A1 and apo B were measured by immunoprecipitation assays, and the lipids and lipoproteins were measured by enzymatic methods.The VAP-1 were measured by ELISA method. The mean levels of total cholesterol, LDL, apo B and VAP-1 in patients with psoriasis were found to be significantly higher than those of healthy subjects (P<0.05. In psoriatic patients, elevation of VAP-1 correlated with elevation of Lp (a) (p = 0.025). This study shows that high serum lipid level and VAP-1, is significantly more common in psoriasis. This fact may be responsible for higher prevalence of cardiovascular accident in psoriatic patients. PMID:22753196

Nemati, Houshang; Khodarahmi, Reza; Rahmani, Ameneh; Ebrahimi, Ali; Amani, Mojtaba; Eftekhari, Kamran

2012-07-03

262

Functional roles of mannose-binding protein in the adhesion, cytotoxicity and phagocytosis of Acanthamoeba castellanii.  

PubMed

Acanthamoeba castellanii is a single-celled protozoan that is widely distributed in the environment and is a well-known of causing human keratitis, a vision-threatening infection. In this study, an ethyl methane sulfonate (EMS) and a selection of saccharide were applied to A. castellanii by chemical mutagenesis. To understand the functional roles of a mannose-binding protein (MBP). A. castellanii were treated with methyl-alpha-D-mannopyranoside abbreviated Man, with and without the EMS pre-treatment, and their adhesion and cytotoxicity were analyzed, using a human brain microvascular endothelial cell (HBMEC) as the target cell. Both EMS and Man mutants exhibited significantly decreased levels of MBP expression and cytotoxicity to HBMEC, but showed similar levels of binding to HBMEC, as compared with the wild type. Of interest was that the exogenous mannose inhibited amoebae (i.e., Man mutant) binding to the HBMEC by <20%. Only the mutant Man exhibited a significant decrease in bacterial uptake, as compared to the wild type, 0.020 vs 0.032 (p<0.05) and proteolytic activity. The results showed that MBP should be clearly provided as the pathogenic target candidate, to further target-based therapy, but EMS mutation should not be associated with initial adhesion and phagocytosis of A. castellanii. PMID:22940016

Kim, Jong-Hyun; Matin, Abdul; Shin, Ho-Joon; Park, Hyun; Yoo, Kyung-Tae; Yuan, Xi-Zhe; Kim, Kwang Sik; Jung, Suk-Yul

2012-08-24

263

Adhesion of mussel foot protein-3 to TiO2 surfaces: the effect of pH.  

PubMed

The underwater adhesion of marine mussels relies on mussel foot proteins (mfps) rich in the catecholic amino acid 3,4-dihydroxyphenylalanine (Dopa). As a side chain, Dopa is capable of strong bidentate interactions with a variety of surfaces, including many minerals and metal oxides. Titanium is among the most widely used medical implant material and quickly forms a TiO2 passivation layer under physiological conditions. Understanding the binding mechanism of Dopa to TiO2 surfaces is therefore of considerable theoretical and practical interest. Using a surface forces apparatus, we explored the force-distance profiles and adhesion energies of mussel foot protein 3 (mfp-3) to TiO2 surfaces at three different pHs (pH 3, 5.5 and 7.5). At pH 3, mfp-3 showed the strongest adhesion force on TiO2, with an adhesion energy of ?-7.0 mJ/m(2). Increasing the pH gives rise to two opposing effects: (1) increased oxidation of Dopa, thus, decreasing availability for the Dopa-mediated adhesion, and (2) increased bidentate Dopa-Ti coordination, leading to the further stabilization of the Dopa group and, thus, an increase in adhesion force. Both effects were reflected in the resonance-enhanced Raman spectra obtained at the three deposition pHs. The two competing effects give rise to a higher adhesion force of mfp-3 on the TiO2 surface at pH 7.5 than at pH 5.5. Our results suggest that Dopa-containing proteins and synthetic polymers have great potential as coating materials for medical implant materials, particularly if redox activity can be controlled. PMID:23452271

Yu, Jing; Wei, Wei; Menyo, Matthew S; Masic, Admir; Waite, J Herbert; Israelachvili, Jacob N

2013-03-14

264

Wood adhesion and adhesives  

Treesearch

... to better understanding of the factors controlling the performance of the bonded ... other wood adhesives, especially when under the more severe durability tests. ... Keywords: Hot melt adhesives, pressure-sensitive adhesives, formaldehyde, ...

265

Purification and characterization of a surface-binding protein from Lactobacillus fermentum RC14 that inhibits adhesion of Enterococcus faecalis 1131  

Microsoft Academic Search

Lactobacilli have been shown to be important in the maintenance of the healthy urogenital flora. One strain, Lactobacillus fermentum RC-14, releases surface-active components which can inhibit adhesion of uropathogenic bacteria. Using a quantitative method for determining inhibition of adhesion, a protein with high anti-adhesive properties against Enterococcus faecalis 1131 was purified. The N-terminal sequence of the 29-kDa protein was identical

Christine Heinemann; Dick B. Janssen; Henk J. Busscher; Henny C. van der Mei; Gregor Reid

2000-01-01

266

Matching structure with function: the GAIN domain of Adhesion-GPCR and PKD1-like proteins.  

PubMed

Elucidation of structural information can greatly facilitate the understanding of molecular function. A recent example is the description of the G-protein-coupled receptor (GPCR) autoproteolysis-inducing (GAIN) domain, an evolutionarily ancient fold present in Adhesion-GPCRs (aGPCRs) and polycystic kidney disease 1 (PKD1)-like proteins. In the past, the peculiar autoproteolytic capacity of both membrane protein families at the conserved GPCR proteolysis site (GPS) had not been described in detail. The physiological performance of aGPCRs and PKD1-like proteins is thought to be regulated through the GPS, but it is debated how. A recent report provides pivotal details by discovery and analysis of the GAIN domain structure that incorporates the GPS motif. Complementary studies have commenced to analyze physiological requirements of the GAIN domain for aGPCR function, indicating that it serves as the linchpin for multiple receptor signals. Structural analysis and functional assays now allow for the dissection of the biological duties conferred through the GAIN domain. PMID:23850273

Prömel, Simone; Langenhan, Tobias; Araç, Demet

2013-07-11

267

Adhesion and fusion efficiencies of human immunodeficiency virus type 1 (HIV-1) surface proteins  

PubMed Central

In about half of patients infected with HIV-1 subtype B, viral populations shift from utilizing the transmembrane protein CCR5 to CXCR4, as well as or instead of CCR5, during late stage progression of the disease. How the relative adhesion efficiency and fusion competency of the viral Env proteins relate to infection during this transition is not well understood. Using a virus-cell fusion assay and live-cell single-molecule force spectroscopy, we compare the entry competency of viral clones to tensile strengths of the individual Env-receptor bonds of Env proteins obtained from a HIV-1 infected patient prior to and during coreceptor switching. The results suggest that the genetic determinants of viral entry were predominantly enriched in the C3, HR1 and CD regions rather than V3. Env proteins can better mediate entry into cells after coreceptor switch; this effective entry capacity does not correlate with the bond strengths between viral Env and cellular receptors.

Dobrowsky, Terrence M.; Rabi, S. Alireza; Nedellec, Rebecca; Daniels, Brian R.; Mullins, James I.; Mosier, Donald E.; Siliciano, Robert F.; Wirtz, Denis

2013-01-01

268

Adhesion and fusion efficiencies of human immunodeficiency virus type 1 (HIV-1) surface proteins.  

PubMed

In about half of patients infected with HIV-1 subtype B, viral populations shift from utilizing the transmembrane protein CCR5 to CXCR4, as well as or instead of CCR5, during late stage progression of the disease. How the relative adhesion efficiency and fusion competency of the viral Env proteins relate to infection during this transition is not well understood. Using a virus-cell fusion assay and live-cell single-molecule force spectroscopy, we compare the entry competency of viral clones to tensile strengths of the individual Env-receptor bonds of Env proteins obtained from a HIV-1 infected patient prior to and during coreceptor switching. The results suggest that the genetic determinants of viral entry were predominantly enriched in the C3, HR1 and CD regions rather than V3. Env proteins can better mediate entry into cells after coreceptor switch; this effective entry capacity does not correlate with the bond strengths between viral Env and cellular receptors. PMID:24145278

Dobrowsky, Terrence M; Rabi, S Alireza; Nedellec, Rebecca; Daniels, Brian R; Mullins, James I; Mosier, Donald E; Siliciano, Robert F; Wirtz, Denis

2013-10-22

269

Adhesion and fusion efficiencies of human immunodeficiency virus type 1 (HIV-1) surface proteins  

NASA Astrophysics Data System (ADS)

In about half of patients infected with HIV-1 subtype B, viral populations shift from utilizing the transmembrane protein CCR5 to CXCR4, as well as or instead of CCR5, during late stage progression of the disease. How the relative adhesion efficiency and fusion competency of the viral Env proteins relate to infection during this transition is not well understood. Using a virus-cell fusion assay and live-cell single-molecule force spectroscopy, we compare the entry competency of viral clones to tensile strengths of the individual Env-receptor bonds of Env proteins obtained from a HIV-1 infected patient prior to and during coreceptor switching. The results suggest that the genetic determinants of viral entry were predominantly enriched in the C3, HR1 and CD regions rather than V3. Env proteins can better mediate entry into cells after coreceptor switch; this effective entry capacity does not correlate with the bond strengths between viral Env and cellular receptors.

Dobrowsky, Terrence M.; Rabi, S. Alireza; Nedellec, Rebecca; Daniels, Brian R.; Mullins, James I.; Mosier, Donald E.; Siliciano, Robert F.; Wirtz, Denis

2013-10-01

270

Strength Dependence of Cadherin-Mediated Adhesions  

PubMed Central

Abstract Traction forces between adhesive cells play an important role in a number of collective cell processes. Intercellular contacts, in particular cadherin-based intercellular junctions, are the major means of transmitting force within tissues. We investigated the effect of cellular tension on the formation of cadherin-cadherin contacts by spreading cells on substrates with tunable stiffness coated with N-cadherin homophilic ligands. On the most rigid substrates, cells appear well-spread and present cadherin adhesions and cytoskeletal organization similar to those classically observed on cadherin-coated glass substrates. However, when cells are cultured on softer substrates, a change in morphology is observed: the cells are less spread, with a more disorganized actin network. A quantitative analysis of the cells adhering on the cadherin-coated surfaces shows that forces are correlated with the formation of cadherin adhesions. The stiffer the substrates, the larger are the average traction forces and the more developed are the cadherin adhesions. When cells are treated with blebbistatin to inhibit myosin II, the forces decrease and the cadherin adhesions disappear. Together, these findings are consistent with a mechanosensitive regulation of cadherin-mediated intercellular junctions through the cellular contractile machinery.

Ladoux, Benoit; Anon, Ester; Lambert, Mireille; Rabodzey, Aleksandr; Hersen, Pascal; Buguin, Axel; Silberzan, Pascal; Mege, Rene-Marc

2010-01-01

271

Investigation of alginate binding to germanium and polystyrene substrata conditioned with mussel adhesive protein  

SciTech Connect

Binding of alginate from Macrocystis pyrifera (kelp) to germanium and polystyrene substrata conditioned with mussel adhesive protein (MAP) from Mytilis edulis, to germanium substrata conditioned with bovine serum albumin (BSA) and polylysine, and to germanium substrata coated with aminopropyltriethoxysilane (APS) was investigated using attenuated total reflection Fourier transform infrared spectrometry. Binding of alginate to MAP appears to be proportional to surface coverage for levels tested. Distinct spectral features appear in the region associated with pyranose ring vibrations upon binding of alginate to MAP, polylysine, and APS, indicating that lysine residues play a prominent role in promoting irreversible adsorption with perturbation of pyranose ring atoms. BSA does not appear to enhance alginate adsorption over that observed on clean germanium and no new spectral features appear as a result of binding. The level of irreversible binding of alginate to germanium and polystyrene substrata conditioned with MAP is similar.

Suci, P.A.; Geesey, G.G. [Montana State Univ., Bozeman, MT (United States). Center for Biofilm Engineering

1995-06-15

272

Collective diffusion coefficient of proteins with hydrodynamic, electrostatic, and adhesive interactions.  

PubMed

A theory is presented for lambdaC, the coefficient of the first-order correction in the density of the collective diffusion coefficient, for protein spheres interacting by electrostatic and adhesive forces. An extensive numerical analysis of the Stokesian hydrodynamics of two moving spheres is given so as to gauge the precise impact of lubrication forces. An effective stickiness is introduced and a simple formula for lambdaC in terms of this variable is put forward. A precise though more elaborate approximation for lambdaC is also developed. These and numerically exact expressions for lambdaC are compared with experimental data on lysozyme at pH 4.5 and a range of ionic strengths between 0.05M and 2M. PMID:17887883

Prinsen, Peter; Odijk, Theo

2007-09-21

273

?1 Integrin is an Adhesion Protein for Sperm Binding to Eggs  

PubMed Central

We investigated the role of ?1 integrin in mammalian fertilization and the mode of inhibition of fertilin?-derived polymers. We determined that polymers displaying the Glu-Cys-Asp peptide from the fertilin? disintegrin domain mediate inhibition of mammalian fertilization through a ?1 integrin receptor on the egg surface. Inhibition of fertilization is a consequence of competition with sperm binding to the cell surface, not activation of an egg-signaling pathway. The presence of the ?1 integrin on the egg surface increases the rate of sperm attachment, but does not alter the total number of sperm that can attach or fuse to the egg. We conclude that the presence of ?1 integrin enhances the initial adhesion of sperm to the egg plasma membrane and that subsequent attachment and fusion are mediated by additional egg and sperm proteins present in the ?1 integrin complex. Therefore, the mechanisms by which sperm fertilize wild-type and ?1 knockout eggs are different.

Baessler, Keith A.; Lee, Younjoo; Sampson, Nicole S.

2009-01-01

274

Chlamydophila (Chlamydia) pneumoniae infection promotes vascular smooth muscle cell adhesion and migration through IQ domain GTPase-activating protein 1.  

PubMed

The mechanisms for Chlamydophila (Chlamydia) pneumoniae (C. pneumoniae) infection-induced atherosclerosis are still unclear. Cell adhesion has important roles in vascular smooth muscle cell (VSMC) migration required in the development of atherosclerosis. However, it is still unknown whether IQ domain GTPase-activating protein 1 (IQGAP1) plays pivotal roles in C. pneumoniae infection-induced the adhesion and migration of rat primary VSMCs. Accordingly, in this study, we demonstrated that rat primary VSMC adhesion (P < 0.001) and migration (P < 0.01) measured by cell adhesion assay and Transwell assay, respectively, were significantly enhanced after C. pneumoniae infection. Reverse transcription-polymerase chain reaction analysis revealed that the mRNA expression levels of IQGAP1 in the infected rat primary VSMCs were found to increase gradually to reach a peak and then decrease gradually to a level similar to the control. We further showed that the increases in rat primary VSMC adhesion to Matrigel (P < 0.001) and migration (P < 0.01) caused by C. pneumoniae infection were markedly inhibited after IQGAP1 knockdown by a pool of four short hairpin RNAs. Taken together, our results suggest that C. pneumoniae infection may promote the adhesion and migration of VSMCs possibly by upregulating the IQGAP1 expression. PMID:22835851

Zhang, Lijun; Li, Xiankui; Zhang, Lijun; Wang, Beibei; Zhang, Tengteng; Ye, Jing

2012-07-23

275

Lateral assembly of the immunoglobulin protein SynCAM 1 controls its adhesive function and instructs synapse formation  

PubMed Central

Synapses are specialized adhesion sites between neurons that are connected by protein complexes spanning the synaptic cleft. These trans-synaptic interactions can organize synapse formation, but their macromolecular properties and effects on synaptic morphology remain incompletely understood. Here, we demonstrate that the synaptic cell adhesion molecule SynCAM 1 self-assembles laterally via its extracellular, membrane-proximal immunoglobulin (Ig) domains 2 and 3. This cis oligomerization generates SynCAM oligomers with increased adhesive capacity and instructs the interactions of this molecule across the nascent and mature synaptic cleft. In immature neurons, cis assembly promotes the adhesive clustering of SynCAM 1 at new axo-dendritic contacts. Interfering with the lateral self-assembly of SynCAM 1 in differentiating neurons strongly impairs its synaptogenic activity. At later stages, the lateral oligomerization of SynCAM 1 restricts synaptic size, indicating that this adhesion molecule contributes to the structural organization of synapses. These results support that lateral interactions assemble SynCAM complexes within the synaptic cleft to promote synapse induction and modulate their structure. These findings provide novel insights into synapse development and the adhesive mechanisms of Ig superfamily members.

Fogel, Adam I; Stagi, Massimiliano; Perez de Arce, Karen; Biederer, Thomas

2011-01-01

276

Cell adhesion properties of hemolin, an insect immune protein in the Ig superfamily.  

PubMed

The isolation of antibacterial peptides from the giant silkmoth Hyalophora cecropia has opened the area of animal antibiotics [Boman, H. G. (1991) Cell 65, 205-207] and the study of insect immune genes has revealed striking similarities to many immune response genes in mammals [Hultmark, D. (1994) Nature 267, 116-117]. However, the molecules and mechanisms behind primordial immune recognition are not understood. One candidate for one such recognition molecule is hemolin, a 48-kDa immunoglobulin-related protein first isolated from H. cecropia, where it is up-regulated upon infection and secreted into the hemolymph. Hemolin was shown to bind to bacteria and to hemocytes, giving rise to changes in hemocyte adhesiveness and intracellular phosphorylation patterns [Faye, I. & Kanost, M. (1997) in Molecular mechanisms of immune responses in insects (Brey, P. T. & Hultmark, D., eds) Chapman and Hall, London]. In the present publication, we give evidence for the presence of a 52-kDa membrane form of hemolin on hemocytes, based on flow-activated cell sorting and membrane protein extractions. In addition we reveal calcium-dependent homophilic binding properties of hemolin, using hemolin-coated microspheres. When biotinylated recombinant hemolin was allowed to bind to hemocyte membranes, higher molecular-mass complexes were formed. Furthermore, we used immunological methods and Northern-blot analysis to demonstrate the presence of hemolin in embryos and retinal discs, suggesting that hemolin is expressed in several tissues at different developmental stages. These results show novel cell adhesion features of hemolin, corroborating its multifunctional character with putative roles in cellular and humoral immunity and in development. PMID:9461284

Bettencourt, R; Lanz-Mendoza, H; Lindquist, K R; Faye, I

1997-12-15

277

Amyloid Beta Precursor Protein and Prion Protein Have a Conserved Interaction Affecting Cell Adhesion and CNS Development  

PubMed Central

Genetic and biochemical mechanisms linking onset or progression of Alzheimer Disease and prion diseases have been lacking and/or controversial, and their etiologies are often considered independent. Here we document a novel, conserved and specific genetic interaction between the proteins that underlie these diseases, amyloid-? precursor protein and prion protein, APP and PRP, respectively. Knockdown of APP and/or PRNP homologs in the zebrafish (appa, appb, prp1, and prp2) produces a dose-dependent phenotype characterized by systemic morphological defects, reduced cell adhesion and CNS cell death. This genetic interaction is surprisingly exclusive in that prp1 genetically interacts with zebrafish appa, but not with appb, and the zebrafish paralog prp2 fails to interact with appa. Intriguingly, appa & appb are largely redundant in early zebrafish development yet their abilities to rescue CNS cell death are differentially contingent on prp1 abundance. Delivery of human APP or mouse Prnp mRNAs rescue the phenotypes observed in app-prp-depleted zebrafish, highlighting the conserved nature of this interaction. Immunoprecipitation revealed that human APP and PrPC proteins can have a physical interaction. Our study reports a unique in vivo interdependence between APP and PRP loss-of-function, detailing a biochemical interaction that considerably expands the hypothesized roles of PRP in Alzheimer Disease.

Wang, Hao; Daude, Nathalie; Wohlgemuth, Serene; Shi, Beipei; Allison, W. Ted

2012-01-01

278

Adsorption of parotid saliva proteins and adhesion of Streptococcus mutans ATCC 21752 to dental fiber-reinforced composites.  

PubMed

The use of fiber-reinforced composites (FRC) in dentistry has increased during recent years. In marginal areas of crowns and removable partial dentures the fibers may become exposed and come into contact with oral tissues, saliva, and microbes. To date, few articles have been published on oral microbial adhesion to FRCs. The aim of this study was to compare different FRCs, their components, and conventional restorative materials with respect to S. mutans ATCC 21752 adhesion and adsorption of specific S. mutans binding proteins. Surface roughness of the materials was also determined. Four different FRCs, a restorative composite, and a high-leucite ceramic material were studied. Polyethylene FRC was found to be significantly rougher than all other materials. Aramid FRC also showed higher surface roughness in comparison with all materials but polyethylene FRC. Without a saliva pellicle, adhesion of S. mutans coincided with surface roughness and polyethylene and aramid FRC promoted S. mutans adhesion better than the other smoother materials. In the presence of salivary pellicle, ceramic and polyethylene FRC bound more bacteria than the other materials studied. Higher quantities of S. mutans binding proteins in the pellicles may in part account for the higher S. mutans adhesion to saliva-coated ceramic and polyethylene FRC. PMID:12808599

Tanner, Johanna; Carlén, Anette; Söderling, Eva; Vallittu, Pekka K

2003-07-15

279

Adhesive protein expression on endothelial cells after contact in vitro with polyethylene terephthalate coated with pyrolytic carbon  

Microsoft Academic Search

This research aims at evaluating the expression of some adhesive proteins on endothelial cell surface after contact with polyethylene terephthalate coated with pyrolytic carbon (PET + PC). Twenty-two different cultures of human umbilical vein endothelial cells (HUVECs) were put in contact with PET + PC. Both HUVECs grown without the biomaterial and HUVECs incubated with endotoxin were used as control.

E. Cenni; D. Granchi; C. R. Arciola; G. Ciapetti; L. Savarino; S. Stea; D. Cavedagna; A. Di Leo; A. Pizzoferrato

1995-01-01

280

The effect of soy protein beverages on serum cell adhesion molecule concentrations in prehypertensive\\/stage 1 hypertensive individuals  

Microsoft Academic Search

Background and Aims: Prehypertensive and hypertensive individuals are at an increased risk of atherosclerotic cardiovascular disease. The role of hypertension in endothelial dysfunction and increased cell adhesion molecule (CAM) expression may lead to atherosclerotic progression. Soy protein and isoflavones have been shown to favorably alter cardiovascular disease risk factors. The aim of this study was to determine the effect of

Michelle Elise Dettmer

2011-01-01

281

Attenuation of mouse mesangial cell contractility by high glucose and mannitol: Involvement of protein kinase C and focal adhesion kinase  

Microsoft Academic Search

Hyperglycemia and mannitol activate protein kinase C (PKC) and induce mesangial cell hypocontractility that subsequently may modulate renal function. Since focal adhesion kinase (FAK) activation is known to be linked with PKC activity, FAK may also be involved in mesangial cell contraction. To facilitate our understanding of the PKC- and FAK-modulating mechanism, we developed an in vitro model of mouse

Jin-Shuen Chen; Herng-Sheng Lee; Jong-Shiaw Jin; Ann Chen; Shih-Hua Lin; Shuk-Man Ka; Yuh-Feng Lin

2004-01-01

282

The endosomal adaptor protein APPL1 impairs the turnover of leading edge adhesions to regulate cell migration  

PubMed Central

Cell migration is a complex process that requires the integration of signaling events that occur in distinct locations within the cell. Adaptor proteins, which can localize to different subcellular compartments, where they bring together key signaling proteins, are emerging as attractive candidates for controlling spatially coordinated processes. However, their function in regulating cell migration is not well understood. In this study, we demonstrate a novel role for the adaptor protein containing a pleckstrin-homology (PH) domain, phosphotyrosine-binding (PTB) domain, and leucine zipper motif 1 (APPL1) in regulating cell migration. APPL1 impairs migration by hindering the turnover of adhesions at the leading edge of cells. The mechanism by which APPL1 regulates migration and adhesion dynamics is by inhibiting the activity of the serine/threonine kinase Akt at the cell edge and within adhesions. In addition, APPL1 significantly decreases the tyrosine phosphorylation of Akt by the nonreceptor tyrosine kinase Src, which is critical for Akt-mediated cell migration. Thus, our results demonstrate an important new function for APPL1 in regulating cell migration and adhesion turnover through a mechanism that depends on Src and Akt. Moreover, our data further underscore the importance of adaptor proteins in modulating the flow of information through signaling pathways.

Broussard, Joshua A.; Lin, Wan-hsin; Majumdar, Devi; Anderson, Bridget; Eason, Brady; Brown, Claire M.; Webb, Donna J.

2012-01-01

283

In Vivo Selection for Neisseria gonorrhoeae Opacity Protein Expression in the Absence of Human Carcinoembryonic Antigen Cell Adhesion Molecules  

Microsoft Academic Search

phenicol-resistant (Cmr) strain and following Cmr Opa populations mixed with a higher percentage of Opa variants of the wild-type (Cms) strain. Reciprocal experiments (Opa Cmr gonococci spiked with Opa Cms bacteria) were consistent with selection of Opa variants. Based on the absence in mice of human carcino- embryonic antigen cell adhesion molecules, the major class of Opa protein adherence receptors,

Amy N. Simms; Ann E. Jerse

2006-01-01

284

Characterization of Syntenin, a Syndecan-binding PDZ Protein, as a Component of Cell Adhesion Sites and Microfilaments  

Microsoft Academic Search

Syntenin is a PDZ protein that binds the cytoplasmic C-terminal FYA motif of the syndecans. Syntenin is widely expressed. In cell fractionation experiments, syntenin partitions between the cytosol and microsomes. Immunofluorescence microscopy localizes endogenous and epitope- tagged syntenin to cell adhesion sites, microfilaments, and the nucleus. Syntenin is composed of at least three domains. Both PDZ domains of syntenin are

Pascale Zimmermann; Daniela Tomatis; Marcela Rosas; Johan Grootjans; Iris Leenaerts; Gisele Degeest; Gunter Reekmans; Christien Coomans; Guido David

2001-01-01

285

Cytoplasmic Domain of Zebrafish Myelin Protein Zero: Adhesive Role Depends on ?-Conformation  

PubMed Central

Solution spectroscopy studies on the cytoplasmic domain of human myelin protein zero (P0) (hP0-cyt) suggest that H-bonding between ?-strands from apposed molecules is likely responsible for the tight cytoplasmic apposition in compact myelin. As a follow-up to these findings, in the current study we used circular dichroism and x-ray diffraction to analyze the same type of model membranes previously used for hP0-cyt to investigate the molecular mechanism underlying the zebrafish cytoplasmic apposition. This space is significantly narrower in teleosts compared with that in higher vertebrates, and can be accounted for in part by the much shorter cytoplasmic domain in the zebrafish protein (zP0-cyt). Circular dichroism measurements on zP0-cyt showed similar structural characteristics to those of hP0-cyt, i.e., the protein underwent a ??? structural transition at lipid/protein (L/P) molar ratios >50, and adopted a ?-conformation at lower L/P molar ratios. X-ray diffraction was carried out on lipid vesicle solutions with zP0-cyt before and after dehydration to study the effect of protein on membrane lipid packing. Solution diffraction revealed the electron-density profile of a single membrane bilayer. Diffraction patterns of dried samples suggested a multilamellar structure with the ?-folded P0-cyt located at the intermembrane space. Our findings support the idea that the adhesive role of P0 at the cytoplasmic apposition in compact myelin depends on the cytoplasmic domain of P0 being in the ?-conformation.

Luo, XiaoYang; Inouye, Hideyo; Gross, Abby A. R.; Hidalgo, Marla M.; Sharma, Deepak; Lee, Daniel; Avila, Robin L.; Salmona, Mario; Kirschner, Daniel A.

2007-01-01

286

Induction of Presynaptic Reexpression of an Adhesion Protein in Lamina II after Dorsal Root Deafferentation in Adult Rat Spinal Cord  

Microsoft Academic Search

Limbic system-associated membrane protein (LAMP), a 64-kDa membrane protein, is an axon guidance adhesion molecule expressed by neurons in limbic system-related areas of the CNS. During development, LAMP is expressed on growing axons, growth cones, and their target neurons, but in adults it is restricted to membranes of somata and dendrites. In the adult spinal cord, LAMP immunoreactivity is found

B. Zhang; P. Levitt; M. Murray

1998-01-01

287

Human tumour-associated cell adhesion protein MN/CA IX: identification of M75 epitope and of the region mediating cell adhesion  

PubMed Central

MN/CA IX is a cell surface protein, strongly associated with several types of human carcinomas. It exerts activity of carbonic anhydrase and capacity of binding to cell surface receptors. In the present work, we used affinity purified MN/CA IX protein to demonstrate that the cells adhere to immobilized MN/CA IX and that the monoclonal antibody M75 abrogates cell attachment to MN/CA IX. Using synthetic oligopeptides, we identified M75 epitope and located it in the proteoglycan domain, which contains a sixfold tandem repeat of six amino acids GEEDLP. From phage display library of random heptapeptides we identified and chemically synthesized those which compete for the epitope with M75 and inhibit adhesion of cells to MN/CA IX. These heptapeptides might serve as lead compounds for drug design. © 2000 Cancer Research Campaign

Zavada, J; Zavadova, Z; Pastorek, J; Biesova, Z; Jezek, J; Velek, J

2000-01-01

288

The Fasciclin-Like Arabinogalactan Proteins of Arabidopsis. A Multigene Family of Putative Cell Adhesion Molecules1  

PubMed Central

Fasciclin-like arabinogalactan proteins (FLAs) are a subclass of arabinogalactan proteins (AGPs) that have, in addition to predicted AGP-like glycosylated regions, putative cell adhesion domains known as fasciclin domains. In other eukaryotes (e.g. fruitfly [Drosophila melanogaster] and humans [Homo sapiens]), fasciclin domain-containing proteins are involved in cell adhesion. There are at least 21 FLAs in the annotated Arabidopsis genome. Despite the deduced proteins having low overall similarity, sequence analysis of the fasciclin domains in Arabidopsis FLAs identified two highly conserved regions that define this motif, suggesting that the cell adhesion function is conserved. We show that FLAs precipitate with ?-glucosyl Yariv reagent, indicating that they share structural characteristics with AGPs. Fourteen of the FLA family members are predicted to be C-terminally substituted with a glycosylphosphatidylinositol anchor, a cleavable form of membrane anchor for proteins, indicating different FLAs may have different developmental roles. Publicly available microarray and expressed sequence tag data were used to select FLAs for further expression analysis. RNA gel blots for a number of FLAs indicate that they are likely to be important during plant development and in response to abiotic stress. FLAs 1,2, and 8 show a rapid decrease in mRNA abundance in response to the phytohormone abscisic acid. Also, the accumulation of FLA1 and FLA2 transcripts differs during callus and shoot development, indicating that the proteins may be significant in the process of competence acquisition and induction of shoot development.

Johnson, Kim L.; Jones, Brian J.; Bacic, Antony; Schultz, Carolyn J.

2003-01-01

289

Preparation of a protein micro-array using a photo-reactive polymer for a cell-adhesion assay.  

PubMed

A protein micro-array, called a "cell chip" was constructed by using a photo-reactive polymer for a cell-adhesion assay. Various amounts of albumin or fibronectin were covalently immobilized on a polystyrene dish using a micro-spotter with a dip pen. First, poly(acrylic acid) carrying azidophenyl groups was synthesized as the photo-reactive polymer. Secondly, the aqueous solution of a photo-reactive polymer (several nanoliters) was cast using the dip pen of the micro-spotter and dried in air. Subsequently, aqueous solutions of proteins were cast on the same place using the micro-spotter. After drying, the dish was irradiated with ultraviolet light. Finally, the immobilization was confirmed by staining with a dye. The immobilization was stable even after washing with Tween-20. The protein-immobilized area depended on the manipulation of the micro-spotter and the size of the dip pen. Subsequently, cell adhesion on the photo-immobilized protein micro-array was investigated. The adhesion behavior of cells depended on the kind of immobilized proteins and the kind of cells. The protein micro-array will be useful for cell diagnosis and for the selection of biomaterials to regulate cell behavior. PMID:12895574

Ito, Yoshihiro; Nogawa, Masayuki

2003-08-01

290

Functional modulation of vascular adhesion protein-1 by a novel splice variant.  

PubMed

Vascular Adhesion Protein-1 (VAP-1) is an endothelial adhesion molecule belonging to the primary amine oxidases. Upon inflammation it takes part in the leukocyte extravasation cascade facilitating transmigration of leukocytes into the inflamed tissue. Screening of a human lung cDNA library revealed the presence of an alternatively spliced shorter transcript of VAP-1, VAP-1?3. Here, we have studied the functional and structural characteristics of VAP-1?3, and show that the mRNA for this splice variant is expressed in most human tissues studied. In comparison to the parent molecule this carboxy-terminally truncated isoform lacks several of the amino acids important in the formation of the enzymatic groove of VAP-1. In addition, the conserved His684, which takes part in coordinating the active site copper, is missing from VAP-1?3. Assays using the prototypic amine substrates methylamine and benzylamine demonstrated that VAP-1?3 is indeed devoid of the semicarbazide-sensitive amine oxidase (SSAO) activity characteristic to VAP-1. When VAP-1?3-cDNA is transfected into cells stably expressing VAP-1, the surface expression of the full-length molecule is reduced. Furthermore, the SSAO activity of the co-transfectants is diminished in comparison to transfectants expressing only VAP-1. The observed down-regulation of both the expression and enzymatic activity of VAP-1 may result from a dominant-negative effect caused by heterodimerization between VAP-1 and VAP-1?3, which was detected in co-immunoprecipitation studies. This alternatively spliced transcript adds thus to the repertoire of potential regulatory mechanisms through which the cell-surface expression and enzymatic activity of VAP-1 can be modulated. PMID:23349812

Kaitaniemi, Sam; Grön, Kirsi; Elovaara, Heli; Salmi, Marko; Jalkanen, Sirpa; Elima, Kati

2013-01-18

291

Induction of the neural cell adhesion molecule and neuronal aggregation by osteogenic protein 1.  

PubMed Central

The neural cell adhesion molecule (N-CAM) plays a fundamental role in nervous system development and regeneration, yet the regulation of the expression of N-CAM in different brain regions has remained poorly understood. Osteogenic protein 1 (OP-1) is a member of the transforming growth factor beta superfamily that is expressed in the nervous system. Treatment of the neuroblastoma-glioma hybrid cell line NG108-15 for 1-4 days with recombinant human OP-1 (hOP-1) induced alterations in cell shape, formation of epithelioid sheets, and aggregation of cells into multilayered clusters. Immunofluorescence studies and Western blots demonstrated a striking differential induction of the three N-CAM isoforms in hOP-1-treated cells. hOP-1 caused a 6-fold up-regulation of the 140-kDa N-CAM, the isoform showing the highest constitutive expression, and a 29-fold up-regulation of the 180-kDa isoform. The 120-kDa isoform was not detected in control NG108-15 cells but was readily identified in hOP-1-treated cells. Incubation of NG108-15 cells with an antisense N-CAM oligonucleotide reduced the induction of N-CAM by hOP-1 and decreased the formation of multilayered cell aggregates. Anti-N-CAM monoclonal antibodies also diminished the formation of multilayered cell aggregates by hOP-1 and decreased cell-cell adhesion when hOP-1-treated NG108-15 cells were dispersed and replated. Thus, hOP-1 produces morphologic changes in NG108-15 cells, at least in part, by inducing N-CAM. These observations suggest that OP-1 or a homologue may participate in the regulation of N-CAM during nervous system development and regeneration. Images

Perides, G; Safran, R M; Rueger, D C; Charness, M E

1992-01-01

292

Functional Modulation of Vascular Adhesion Protein-1 by a Novel Splice Variant  

PubMed Central

Vascular Adhesion Protein-1 (VAP-1) is an endothelial adhesion molecule belonging to the primary amine oxidases. Upon inflammation it takes part in the leukocyte extravasation cascade facilitating transmigration of leukocytes into the inflamed tissue. Screening of a human lung cDNA library revealed the presence of an alternatively spliced shorter transcript of VAP-1, VAP-1?3. Here, we have studied the functional and structural characteristics of VAP-1?3, and show that the mRNA for this splice variant is expressed in most human tissues studied. In comparison to the parent molecule this carboxy-terminally truncated isoform lacks several of the amino acids important in the formation of the enzymatic groove of VAP-1. In addition, the conserved His684, which takes part in coordinating the active site copper, is missing from VAP-1?3. Assays using the prototypic amine substrates methylamine and benzylamine demonstrated that VAP-1?3 is indeed devoid of the semicarbazide-sensitive amine oxidase (SSAO) activity characteristic to VAP-1. When VAP-1?3-cDNA is transfected into cells stably expressing VAP-1, the surface expression of the full-length molecule is reduced. Furthermore, the SSAO activity of the co-transfectants is diminished in comparison to transfectants expressing only VAP-1. The observed down-regulation of both the expression and enzymatic activity of VAP-1 may result from a dominant-negative effect caused by heterodimerization between VAP-1 and VAP-1?3, which was detected in co-immunoprecipitation studies. This alternatively spliced transcript adds thus to the repertoire of potential regulatory mechanisms through which the cell-surface expression and enzymatic activity of VAP-1 can be modulated.

Kaitaniemi, Sam; Gron, Kirsi; Elovaara, Heli; Salmi, Marko; Jalkanen, Sirpa; Elima, Kati

2013-01-01

293

The Heparin-Binding Activity of Secreted Modular Calcium-Binding Protein 1 (SMOC-1) Modulates Its Cell Adhesion Properties  

PubMed Central

Secreted modular calcium-binding proteins 1 and 2 (SMOC-1 and SMOC-1) are extracellular calcium- binding proteins belonging to the BM-40 family of proteins. In this work we have identified a highly basic region in the extracellular calcium-binding (EC) domain of the SMOC-1 similar to other known glycosaminoglycan-binding motifs. Size-exclusion chromatography shows that full length SMOC-1 as well as its C-terminal EC domain alone bind heparin and heparan sulfate, but not the related chondroitin sulfate or dermatan sulfate glycosaminoglycans. Intrinsic tryptophan fluorescence measurements were used to quantify the binding of heparin to full length SMOC-1 and the EC domain alone. The calculated equilibrium dissociation constants were in the lower micromolar range. The binding site consists of two antiparallel alpha helices and mutagenesis experiments have shown that heparin-binding residues in both helices must be replaced in order to abolish heparin binding. Furthermore, we show that the SMOC-1 EC domain, like the SMOC-2 EC domain, supports the adhesion of epithelial HaCaT cells. Heparin-binding impaired mutants failed to support S1EC-mediated cell adhesion and together with the observation that S1EC in complex with soluble heparin attenuated cell adhesion we conclude that a functional and accessible S1EC heparin-binding site mediates adhesion of epithelial cells to SMOC-1.

Klemencic, Marina; Novinec, Marko; Maier, Silke; Hartmann, Ursula; Lenarcic, Brigita

2013-01-01

294

Effects of protein tyrosine kinase inhibitors on cytokine-induced adhesion molecule expression by human umbilical vein endothelial cells.  

PubMed Central

1. Endothelial cells can be stimulated by the pro-inflammatory cytokines interleukin (IL)-1 alpha and tumour necrosis factor (TNF) alpha to express the leukocyte adhesion molecules E-selectin, vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1 but the intracellular signalling mechanisms leading to this expression are incompletely understood. We have investigated the role of protein tyrosine kinases (PTK) in adhesion molecule expression by cytokine-activated human umbilical vein endothelial cells (HUVEC) using the PTK inhibitors genistein and herbimycin A, and the protein tyrosine phosphatase (PTP) inhibitor sodium orthovanadate. 2. Maximal E-selectin expression induced by incubation of HUVEC for 4 h with IL-1 alpha (100 u ml-1) and TNF alpha (100 u ml-1) was dose-dependently inhibited by genistein and herbimycin A. Although similar effects were seen on phorbol 12-myristate, 13-acetate (PMA)-induced expression, this was not due to inhibition of protein kinase C (PKC) activity as the selective inhibitors of PKC, bisindolylmaleimide (BIM), Ro31-7549 or Ro31-8220 did not affect IL-1 alpha- or TNF alpha-induced E-selectin expression at concentrations which maximally inhibited PMA-induced expression. 3. Genistein inhibited VCAM-1 expression induced by incubation of HUVEC for 24 h with TNF alpha or IL-1 alpha whereas it did not affect ICAM-1 expression induced by 24 h incubation with either of these cytokines. Herbimycin A inhibited both VCAM-1 and ICAM-1 expression induced by TNF alpha. 4. Basal expression of E-selectin, VCAM-1 and ICAM-1 was dose-dependently enhanced by sodium orthovanadate. In contrast, vanadate differentially affected TNF alpha-induced expression of these molecules with maximal E-selectin and ICAM-1 expression being slightly enhanced and VCAM-1 expression dose-dependently reduced. 5. We also studied the effects of PTK and PTP inhibitors on adhesion of the human pre-myeloid cell line U937 to TNF alpha-stimulated HUVEC. Adhesion of U937 cells to HUVEC pretreated for 4 or 24 h with TNF alpha was dose-dependently inhibited by genistein and herbimycin A but unaffected by daidzein. Adhesion of U937 cells after 4 h was partially inhibited by blocking antibodies against both E-selectin and VCAM-1 but after 24 h was only inhibited by anti-VCAM-1. 6. Sodium orthovanadate had no effect on TNF alpha-induced U937 adhesion but dose-dependently enhanced adhesion to unstimulated HUVEC. Vanadate-induced adhesion was inhibited by an antibody against VCAM-1. 7. These results demonstrate that PTK-mediated phosphorylation events are important for the regulation of adhesion molecule expression by human endothelial cells, and additionally show that PTK inhibitors differentially affect upregulation of different adhesion molecules, implicating divergent regulatory pathways for cytokine-induced adhesion molecule expression.

May, M. J.; Wheeler-Jones, C. P.; Pearson, J. D.

1996-01-01

295

Composites containing albumin protein or cyanoacrylate adhesives and biodegradable scaffolds: II. In vivo wound closure study in a rat model  

NASA Astrophysics Data System (ADS)

Our Scaffold-Enhanced Biological Adhesive (SEBA) system was investigated as an alternative to sutures or adhesives alone for repair of wounds. Two scaffold materials were investigated: (i) a synthetic biodegradable material fabricated from poly(L-lactic-co-glycolic acid); and (ii) a biologic material, small intestinal submucosa, manufactured by Cook BioTech. Two adhesive materials were also investigated: (i) a biologic adhesive composed of 50%(w/v) bovine serum albumin solder and 0.5mg/ml indocyanine green dye mixed in deionized water, and activated with an 808-nm diode laser; and (ii) Ethicon"s Dermabond, a 2-octyl-cyanoacrylate. The tensile strength and time-to-failure of skin incisions repaired in vivo in a rat model were measured at seven days postoperative. Incisions closed by protein solder alone, by Dermabond alone, or by suture, were also tested for comparison. The tensile strength of repairs formed using the SEBA system were 50% to 65% stronger than repairs formed by suture or either adhesive alone, with significantly less variations within each experimental group (average standard deviations of 15% for SEBA versus 38% for suture and 28% for adhesive alone). In addition, the time-to-failure curves showed a longevity not previously seen with the suture or adhesive alone techniques. The SEBA system acts to keep the dermis in tight apposition during the critical early phase of wound healing when tissue gaps are bridged by scar and granulation tissue. It has the property of being more flexible than either of the adhesives alone and may allow the apposed edges to move in conjunction with each other as a unit for a longer period of time and over a greater range of stresses than adhesives alone. This permits more rapid healing and establishment of integrity since the microgaps between the dermis edges are significantly reduced. By the time the scaffolds are sloughed from the wound site, there is greater strength and healing than that produced by adhesive alone or by wounds following suture removal. This hypothesis is supported by the data of this study, as well as, the acute tensile strength data of Part I of this study.

McNally-Heintzelman, Karen M.; Heintzelman, Douglas L.; Duffy, Mark T.; Bloom, Jeffrey N.; Soller, Eric C.; Gilmour, Travis M.; Hoffman, Grant T.; Edward, Deepak

2004-07-01

296

Surface conjugation of zwitterionic polymers to inhibit cell adhesion and protein adsorption.  

PubMed

Non-fouling surfaces that resist non-specific protein adsorption and cell adhesion are desired for many biomedical applications such as blood-contact devices and biosensors. Therefore, surface conjugation of anti-fouling molecules has been the focus of many studies. In this study, layer-by-layer polyelectrolyte deposition was applied to create an amine-rich platform for conjugation of zwitterionic polymers. A tri-layer polyelectrolyte (TLP) coating representing poly(ethylene imine) (PEI), poly(acrylic acid)-g-azide and PEI was deposited on various polymeric substrates via layer-by-layer deposition and then crosslinked via UV irradiation. Carboxyl-terminated poly(sulfobetaine methacrylate) p(SBMA) or poly(carboxybetaine methacrylate) p(CBMA) was then conjugated onto TLP coated substrates via a carbodiimide reaction. Our results demonstrate that the zwitterionic polymers could be easily conjugated over a wide pH range except under alkaline conditions, and almost completely block protein adsorption and the attachment of L929 cells and platelets. Therefore, this method has outstanding potential in biomedical applications that require low-fouling surfaces. PMID:23500725

Chien, Hsiu-Wen; Tsai, Chih-Chi; Tsai, Wei-Bor; Wang, Meng-Jiy; Kuo, Wei-Hsuan; Wei, Ta-Chin; Huang, Sheng-Tung

2013-02-18

297

Universal method for protein bioconjugation with nanocellulose scaffolds for increased cell adhesion.  

PubMed

Bacterial nanocellulose (BNC) is an emerging biomaterial since it is biocompatible, integrates well with host tissue and can be biosynthesized in desired architecture. However, being a hydrogel, it exhibits low affinity for cell attachment, which is crucial for the cellular fate process. To increase cell attachment, the surface of BNC scaffolds was modified with two proteins, fibronectin and collagen type I, using an effective bioconjugation method applying 1-cyano-4-dimethylaminopyridinium (CDAP) tetrafluoroborate as the intermediate catalytic agent. The effect of CDAP treatment on cell adhesion to the BNC surface is shown for human umbilical vein endothelial cells and the mouse mesenchymal stem cell line C3H10T1/2. In both cases, the surface modification increased the number of cells attached to the surfaces. In addition, the morphology of the cells indicated more healthy and viable cells. CDAP activation of bacterial nanocellulose is shown to be a convenient method to conjugate extracellular proteins to the scaffold surfaces. CDAP treatment can be performed in a short period of time in an aqueous environment under heterogeneous and mild conditions preserving the nanofibrillar network of cellulose. PMID:24094166

Kuzmenko, Volodymyr; Sämfors, Sanna; Hägg, Daniel; Gatenholm, Paul

2013-07-30

298

Proteinaceous determinants of surface colonization in bacteria: bacterial adhesion and biofilm formation from a protein secretion perspective  

PubMed Central

Bacterial colonization of biotic or abiotic surfaces results from two quite distinct physiological processes, namely bacterial adhesion and biofilm formation. Broadly speaking, a biofilm is defined as the sessile development of microbial cells. Biofilm formation arises following bacterial adhesion but not all single bacterial cells adhering reversibly or irreversibly engage inexorably into a sessile mode of growth. Among molecular determinants promoting bacterial colonization, surface proteins are the most functionally diverse active components. To be present on the bacterial cell surface, though, a protein must be secreted in the first place. Considering the close association of secreted proteins with their cognate secretion systems, the secretome (which refers both to the secretion systems and their protein substrates) is a key concept to apprehend the protein secretion and related physiological functions. The protein secretion systems are here considered in light of the differences in the cell-envelope architecture between diderm-LPS (archetypal Gram-negative), monoderm (archetypal Gram-positive) and diderm-mycolate (archetypal acid-fast) bacteria. Besides, their cognate secreted proteins engaged in the bacterial colonization process are regarded from single protein to supramolecular protein structure as well as the non-classical protein secretion. This state-of-the-art on the complement of the secretome (the secretion systems and their cognate effectors) involved in the surface colonization process in diderm-LPS and monoderm bacteria paves the way for future research directions in the field.

Chagnot, Caroline; Zorgani, Mohamed A.; Astruc, Thierry; Desvaux, Mickael

2013-01-01

299

Mechanisms of Epithelial Cell-Cell Adhesion and Cell Compaction Revealed by High-resolution Tracking of E-Cadherin-Green Fluorescent Protein  

Microsoft Academic Search

Cadherin-mediated adhesion initiates cell re- organization into tissues, but the mechanisms and dy- namics of such adhesion are poorly understood. Using time-lapse imaging and photobleach recovery analyses of a fully functional E-cadherin\\/GFP fusion protein, we define three sequential stages in cell-cell adhesion and provide evidence for mechanisms involving E-cadherin and the actin cytoskeleton in transitions between these stages. In the

Cynthia L. Adams; Yih-Tai Chen; Stephen J Smith; W. James Nelson

1998-01-01

300

The Adhesion GPCRs: A unique family of G protein-coupled receptors with important roles in both central and peripheral tissues  

Microsoft Academic Search

.  G protein-coupled receptors (GPCRs) are a diverse superfamily of membrane-bound receptors. The second largest subgroup of\\u000a GPCRs, the Adhesion GPCRs, has 33 members in humans. Phylogenetic analysis of the entire repertoire of the seven transmembrane- domain (7TM)\\u000a regions of GPCRs shows that the Adhesion GPCRs form a distinct family. Adhesion GPCRs are characterised by (1) long N termini with multiple

T. K. Bjarnadóttir; R. Fredriksson; H. B. Schiöth

2007-01-01

301

Protein adsorption mechanisms determine the efficiency of thermally controlled cell adhesion on poly(N-isopropyl acrylamide) brushes.  

PubMed

This study investigated the impact of the protein adsorption mechanism(s) on the efficiency of thermally controlled cell adhesion and release from poly(N-isopropyl acrylamide) brushes. Large format polymer gradients were used to screen for grafting densities and substrate chemistries that alter both cell adhesion at 37 °C and rapid cell release at 25 °C. In particular, the grafting conditions investigated allowed protein adsorption to the underlying substrate, penetration of the brush only, or adsorption to the outer edge of the film. At an average molecular weight of 30 kDa (degree of polymerization N ? 270), the results show that robust protein adsorption to polymer brushes impairs rapid cell release below the lower critical solution temperature. Conversely, grafting conditions that permit protein penetration of the brush but block strong adsorption to the underlying substrate support cell adhesion above the transition temperature and ensure efficient cell recovery at lower temperature. These findings demonstrate the impact of protein adsorption mechanisms, surface chemistry, and polymer properties on thermally controlled cell capture and release. PMID:23214990

Choi, Sangwook; Choi, Byung-Chan; Xue, Changying; Leckband, Deborah

2012-12-20

302

Interactions of the cell adhesion molecule nectin with transmembrane and peripheral membrane proteins for pleiotropic functions  

Microsoft Academic Search

.  Cell adhesion molecules (CAMs) have been implicated in the control of a wide variety of cellular processes, such as cell adhesion,\\u000a polarization, survival, movement, and proliferation. Nectins have emerged as immunoglobulin-like CAMs that participate in\\u000a calcium-independent cell-cell adhesion by homophilic and heterophilic trans-interactions with nectins and nectin-like molecules. Nectin-based cell-cell adhesion exerts its function independently or\\u000a in cooperation with other

Y. Rikitake; Y. Takai

2008-01-01

303

The function of chaperone proteins in the assemblage of protein complexes involved in gamete adhesion and fusion processes.  

PubMed

The remarkable complexity of the molecular events governing adhesion and fusion of the male and female gametes is becoming apparent. Novel research suggests that these highly specific cellular interactions are facilitated by multiprotein complexes that are delivered to and/or assembled on the surface of the gametes by molecular chaperones in preparation for sperm-egg interaction. While the activation of these molecular chaperones and the mechanisms by which they shuttle proteins to the surface of the cell remain the subject of ongoing investigation, a compelling suggestion is that these processes are augmented by dynamic membrane microdomains or lipid rafts that migrate to the apical region of the sperm head after capacitation. Preliminary studies of the oocyte plasma membrane have also revealed the presence of lipid rafts comprising several molecular chaperones, raising the possibility that similar mechanisms may be involved in the activation of maternal fusion machinery and the regulation of oocyte plasma membrane integrity. Despite these findings, the analysis of oocyte surface multiprotein complexes is currently lacking. Further analyses of the intermediary proteins that facilitate the expression of key players in sperm-egg fusion are likely to deliver important insights into this unique event, which culminates in the cytoplasmic continuity of the male and female gametes. PMID:23166368

Bromfield, Elizabeth G; Nixon, Brett

2013-01-24

304

Vascular adhesion protein-1 and renalase in regard to diabetes in hemodialysis patients  

PubMed Central

Introduction Vascular adhesion protein-1 (VAP-1) is a copper-containing semicarbazide-sensitive amine oxidase (SSAO) secreted by vascular smooth muscle cells, adipocytes, and endothelial cells with functional monoamine oxidase activity. Renalase, with possible monoamine oxidase activity, which breaks down catecholamines like SSAO, is also expressed in the endothelium as well as in the kidney. The aim of the study was to assess VAP-1 level and its correlation with renalase level in 60 hemodialyzed (HD) patients. Material and methods Complete blood count, urea, serum lipids, fasting glucose and creatinine were studied by the standard laboratory method in the hospital central laboratory. We assessed VAP-1 and renalase with commercially available assays. Results The mean level of VAP-1 as well as renalase was significantly higher in HD patients when compared to the control group (291.01 ±94.91 ng/ml vs. 158.34 ±56.89 ng/ml, p < 0.01; 27.53 ±9.394.91 µg/ml vs. 4.00 ±1.37 µg/ml, p < 0.001, respectively). In hemodialysis patients VAP-1 correlated with presence of diabetes (r = 0.27, p < 0.05), presence of hypertension (r = 0.32, p < 0.05), use of calcium channel blockers (r = 0.30, p < 0.05), use of ?-blockers (r = 0.25, p < 0.05), ejection fraction (r = –0.38, p < 0.01), systolic blood pressure before (r = 0.52, p < 0.001) and after hemodialysis (r = 0.30, p < 0.01), and weight gain (r = 0.41, p < 0.01). Renalase was not significantly different in diabetic and non-diabetic patients or between hypertensive and normotensive patients. In multiple regression analysis VAP-1 was predicted 77% by serum ejection fraction and fibrinogen. Conclusions Vascular adhesion protein-1, elevated in patients on hemodialysis, was predominantly dependent on blood pressure and diabetes, both factors associated with endothelial damage and promoting cardiovascular complications. Renalase appeared to be unrelated to VAP, at least in the HD population.

Koc-Zorawska, Ewa; Zbroch, Edyta; Malyszko, Jacek; Mysliwiec, Michal

2012-01-01

305

Effect of avidin-like proteins and biotin modification on mesenchymal stem cell adhesion.  

PubMed

The avidin-biotin system is a highly specific reaction that has been used in a wide range of biomedical applications, including surface modification and cell patterning. We systematically examined a number of avidin derivatives as the basis for a simple and cost effective tissue culture polystyrene substrate surface modification for human stem cell culture. Non-specific adhesion between human mesenchymal stem cells and various avidin derivatives, media conditions, and subsequent biotinylation reactions was quantified. We observed significant non-specific cell adhesion to avidin and strepthavidin, indicating that previous observations using this system may be artifactual. Seeding of cells in serum free media, blocking with bovine serum albumin, and the use of the avidin derivative neutravidin were all necessary for elimination of background adhesion. Neutravidin conjugated with biotinylated bsp-RGD(15) peptide provided the most robust cell adhesion, as well as the greatest increase in cell adhesion over background levels. PMID:23452388

Schmidt, Ray C; Healy, Kevin E

2013-02-27

306

Serum vascular adhesion protein-1 level is higher in smokers than non-smokers.  

PubMed

Abstract Background: Semicarbazide-sensitive amine oxidase (SSAO)/vascular adhesion protein-1 (VAP-1) is involved in the pathogenesis of both atherosclerosis and cancer. Because chemical components and metabolites of cigarettes are deaminated by SSAO, the relationship between smoking and serum SSAO/VAP-1 was studied in humans. Methods: A total of 451 non-diabetic and normoalbuminuric Han Chinese subjects were recruited to participate in this study. Smoking history was obtained by using a questionnaire and those who smoked more than 100 cigarettes during a 6-month period were considered smokers. Serum VAP-1 concentration was measured by time-resolved immunofluorometric assay. Age, gender, waist circumference and estimated glomerular filtration rate (GFR) were adjusted in different statistical models. Results: Smokers were mainly male (85.7% versus 26.3%) and were more obese than non-smokers (p?

Wang, Yi-Chia; Li, Hung-Yuan; Wei, Jung-Nan; Lin, Mao-Shin; Shih, Shyang-Rong; Hua, Cyue-Huei; Smith, David J; Vanio, Jani; Chuang, Lee-Ming

2013-06-27

307

Inhibition of vascular adhesion protein-1 suppresses endotoxin-induced uveitis.  

PubMed

Inflammatory leukocyte accumulation is a common feature of major ocular diseases, such as uveitis, diabetic retinopathy, and age-related macular degeneration. Vascular adhesion protein-1 (VAP-1), a cell surface and soluble molecule that possesses semicarbazide-sensitive amine oxidase (SSAO) activity, is involved in leukocyte recruitment. However, the expression of VAP-1 in the eye and its contribution to ocular inflammation are unknown. Here, we investigated the role of VAP-1 in an established model of ocular inflammation, the endotoxin-induced uveitis (EIU), using a novel and specific inhibitor. Our inhibitor has a half-maximal inhibitory concentration (IC(50)) of 0.007 microM against human and 0.008 microM against rat SSAO, while its IC(50) against the functionally related monoamine oxidase (MAO) -A and MAO-B is >10 microM. In the retina, VAP-1 was exclusively expressed in the vasculature, and its expression level was elevated during EIU. VAP-1 inhibition in EIU animals significantly suppressed leukocyte recruitment to the anterior chamber, vitreous, and retina, as well as retinal endothelial P-selectin expression. Our data suggest an important role for VAP-1 in the recruitment of leukocytes to the immune-privileged ocular tissues during acute inflammation. VAP-1 inhibition may become a novel strategy in the treatment of ocular inflammatory diseases. PMID:18032635

Noda, Kousuke; Miyahara, Shinsuke; Nakazawa, Toru; Almulki, Lama; Nakao, Shintaro; Hisatomi, Toshio; She, Haicheng; Thomas, Kennard L; Garland, Rebecca C; Miller, Joan W; Gragoudas, Evangelos S; Kawai, Yosuke; Mashima, Yukihiko; Hafezi-Moghadam, Ali

2007-11-21

308

Mussel adhesive protein-based whole cell array biosensor for detection of organophosphorus compounds.  

PubMed

A whole cell array biosensor for the efficient detection of neurotoxic organophosphate compounds (OPs) was developed through the immobilization of recombinant Escherichia coli cells containing periplasmic-expressing organophosphorus hydrolase (OPH) onto the surface of a 96-well microplate using mussel adhesive protein (MAP) as a microbial cell-immobilizing linker. Both the paraoxon-hydrolyzing activity and fluorescence microscopy analyses demonstrated that the use of MAP in a whole cell biosensor increased the cell-immobilizing efficiency and enhanced the stability of immobilized cells compared to a simple physical adsorption-based whole cell system. Scanning electron microscopic analyses also showed that the E. coli cells were effectively immobilized on the MAP-coated surface without any pretreatment steps. The whole cell array biosensor system, prepared using optimal MAP coating (50 ?g/cm(2)) and cell loading (4 OD(600)), detected paraoxon levels as low as 5 ?M with high reproducibility, and its quantitative detection range was ~5-320 ?M. The MAP-based whole cell array biosensor showed a good long-term stability for 28 day with 80% retained activity and a reusability of up to 20 times. In addition, paraoxon in tap water was also successfully detected without a reduction in sensitivity. Our results indicate that the proposed MAP-based whole cell array system could be used as a potential platform for a stable and reusable whole cell biosensor. PMID:22944022

Kim, Chang Sup; Choi, Bong-Hyuk; Seo, Jeong Hyun; Lim, Geunbae; Cha, Hyung Joon

2012-08-17

309

Soluble intercellular adhesion molecule and C-reactive protein as early markers of infection in newborns.  

PubMed

In order to find a reliable early marker of infection in newborns a study with simultaneous determination of soluble Intercellular Adhesion Molecule-1 (sICAM-1) and C-Reactive Protein (CRP) was planned. Prospectively 90 babies < 5 days of age suspect of infection were included. Retrospectively this population was classified into an "infected" group (n = 45) and a "non-infected" group (n = 45). For each of these two groups we calculated the sensitivity, specificity and predictive values of sICAM-1 and CRP as early markers of infection. We determined the best cut-off level for sICAM-1 to be 300 micrograms/l and for CRP 5 mg/l. As a biochemical test for infection in the newborns the sensitivity and negative predictive value for CRP were 0.69 and 0.73 respectively. When sICAM-1 was added and CRP and s-ICAM-1 were used in combination the sensitivity improved significantly to 0.93, p < 0.01 and the negative predictive value improved to 0.92, p < 0.05. In normal 5-8 days old babies' sICAM-1 was significantly higher than at birth (cord blood), p < 0.0001. In conclusion, sICAM-1 and CRP in combination are better than CRP as a primary test for identification of infection in babies < 5 days of age. PMID:10875093

Hansen, A B; Verder, H; Staun-Olsen, P

2000-01-01

310

Conserved Roles of the Prion Protein Domains on Subcellular Localization and Cell-Cell Adhesion  

PubMed Central

Analyses of cultured cells and transgenic mice expressing prion protein (PrP) deletion mutants have revealed that some properties of PrP -such as its ability to misfold, aggregate and trigger neurotoxicity- are controlled by discrete molecular determinants within its protein domains. Although the contributions of these determinants to PrP biosynthesis and turnover are relatively well characterized, it is still unclear how they modulate cellular functions of PrP. To address this question, we used two defined activities of PrP as functional readouts: 1) the recruitment of PrP to cell-cell contacts in Drosophila S2 and human MCF-7 epithelial cells, and 2) the induction of PrP embryonic loss- and gain-of-function phenotypes in zebrafish. Our results show that homologous mutations in mouse and zebrafish PrPs similarly affect their subcellular localization patterns as well as their in vitro and in vivo activities. Among PrP’s essential features, the N-terminal leader peptide was sufficient to drive targeting of our constructs to cell contact sites, whereas lack of GPI-anchoring and N-glycosylation rendered them inactive by blocking their cell surface expression. Importantly, our data suggest that the ability of PrP to homophilically trans-interact and elicit intracellular signaling is primarily encoded in its globular domain, and modulated by its repetitive domain. Thus, while the latter induces the local accumulation of PrPs at discrete punctae along cell contacts, the former counteracts this effect by promoting the continuous distribution of PrP. In early zebrafish embryos, deletion of either domain significantly impaired PrP’s ability to modulate E-cadherin cell adhesion. Altogether, these experiments relate structural features of PrP to its subcellular distribution and in vivo activity. Furthermore, they show that despite their large evolutionary history, the roles of PrP domains and posttranslational modifications are conserved between mouse and zebrafish.

Radon, Yvonne; Sempou, Emily; Jechow, Katharina; Stuermer, Claudia A. O.; Malaga-Trillo, Edward

2013-01-01

311

Conserved roles of the prion protein domains on subcellular localization and cell-cell adhesion.  

PubMed

Analyses of cultured cells and transgenic mice expressing prion protein (PrP) deletion mutants have revealed that some properties of PrP -such as its ability to misfold, aggregate and trigger neurotoxicity- are controlled by discrete molecular determinants within its protein domains. Although the contributions of these determinants to PrP biosynthesis and turnover are relatively well characterized, it is still unclear how they modulate cellular functions of PrP. To address this question, we used two defined activities of PrP as functional readouts: 1) the recruitment of PrP to cell-cell contacts in Drosophila S2 and human MCF-7 epithelial cells, and 2) the induction of PrP embryonic loss- and gain-of-function phenotypes in zebrafish. Our results show that homologous mutations in mouse and zebrafish PrPs similarly affect their subcellular localization patterns as well as their in vitro and in vivo activities. Among PrP's essential features, the N-terminal leader peptide was sufficient to drive targeting of our constructs to cell contact sites, whereas lack of GPI-anchoring and N-glycosylation rendered them inactive by blocking their cell surface expression. Importantly, our data suggest that the ability of PrP to homophilically trans-interact and elicit intracellular signaling is primarily encoded in its globular domain, and modulated by its repetitive domain. Thus, while the latter induces the local accumulation of PrPs at discrete punctae along cell contacts, the former counteracts this effect by promoting the continuous distribution of PrP. In early zebrafish embryos, deletion of either domain significantly impaired PrP's ability to modulate E-cadherin cell adhesion. Altogether, these experiments relate structural features of PrP to its subcellular distribution and in vivo activity. Furthermore, they show that despite their large evolutionary history, the roles of PrP domains and posttranslational modifications are conserved between mouse and zebrafish. PMID:23936187

Solis, Gonzalo P; Radon, Yvonne; Sempou, Emily; Jechow, Katharina; Stuermer, Claudia A O; Málaga-Trillo, Edward

2013-07-31

312

The impact of dendrimer-grafted modifications to model silicon surfaces on protein adsorption and bacterial adhesion  

Microsoft Academic Search

In the oral cavity, omnipresent salivary protein films (pellicle) mediate bacterial adhesion and biofilm formation on natural tissues as well as on artificial implant surfaces, which may cause serious infectious diseases like periimplantitis. The purpose of this in vitro study was to investigate the adsorption\\/desorption behaviour of human saliva on model surfaces grafted with polyamidoamine (PAMAM) dendrimer molecules compared to self-assembled

Mirjam Eichler; Verena Katzur; Lutz Scheideler; Michael Haupt; Juergen Geis-Gerstorfer; Gottfried Schmalz; Stefan Ruhl; Rainer Müller; Frank Rupp

2011-01-01

313

Development of a rapid immunochromatographic test using a recombinant thrombospondin-related adhesive protein of Babesia gibsoni.  

PubMed

We developed an immunochromatographic test (ICT) with the full-length of thrombospondin-related adhesive protein of Babesia gibsoni expressed by the modified expression method. The developed ICT showed high sensitivity, specificity, and kappa value with a reference test (100%, 93.78%, and 0.8976, respectively), indicating that the ICT could be a new practical diagnostic test for B. gibsoni infection. PMID:22795671

Goo, Youn-Kyoung; Lee, Naeun; Terkawi, Mohamad Alaa; Luo, Yuzi; Aboge, Gabriel Oluga; Nishikawa, Yoshifumi; Suzuki, Hiroshi; Kim, Suk; Xuan, Xuenan

2012-06-26

314

Lactobacillus plantarum surface layer adhesive protein protects intestinal epithelial cells against tight junction injury induced by enteropathogenic Escherichia coli  

Microsoft Academic Search

Lactobacillus plantarum (LP) has previously been used for the treatment and prevention of intestinal disorders and disease. However, the role of the\\u000a LP surface layer adhesive protein (SLAP) in inhibition of epithelial cell disruption is not fully understood. The aim of the\\u000a present study was to investigate the protective effects of purified SLAP on Caco-2 cells infected with enteropathogenic Escherichia

Zhihua LiuTongyi; Tongyi Shen; Peng Zhang; Yanlei Ma; Huanlong Qin

2011-01-01

315

A Role for the Protein Tyrosine Phosphatase CD45 in Macrophage Adhesion through the Regulation of Paxillin Degradation  

PubMed Central

CD45 is a protein tyrosine phosphatase expressed on all cells of hematopoietic origin that is known to regulate Src family kinases. In macrophages, the absence of CD45 has been linked to defects in adhesion, however the molecular mechanisms involved remain poorly defined. In this study, we show that bone marrow derived macrophages from CD45-deficient mice exhibit abnormal cell morphology and defective motility. These defects are accompanied by substantially decreased levels of the cytoskeletal-associated protein paxillin, without affecting the levels of other proteins. Degradation of paxillin in CD45-deficient macrophages is calpain-mediated, as treatment with a calpain inhibitor restores paxillin levels in these cells and enhances cell spreading. Inhibition of the tyrosine kinases proline-rich tyrosine kinase (Pyk2) and focal adhesion kinase (FAK), kinases that are capable of mediating tyrosine phosphorylation of paxillin, also restored paxillin levels, indicating a role for these kinases in the CD45-dependent regulation of paxillin. These data demonstrate that CD45 functions to regulate Pyk2/FAK activity, likely through the activity of Src family kinases, which in turn regulates the levels of paxillin to modulate macrophage adhesion and migration.

St-Pierre, Joelle; Ostergaard, Hanne L.

2013-01-01

316

Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action  

SciTech Connect

Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

Zhang, Haimou [Center for Infection and Immunity Research, School of Life Sciences, Hubei University, Wuhan, Hubei (China); Qin, Gangjian [Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL (United States); Liang, Gang [Children's Hospital, Harvard Medical School, Boston, MA (United States); Li, Jinan [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Chiu, Isaac [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Barrington, Robert A. [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Liu, Dongxu [Center for Infection and Immunity Research, School of Life Sciences, Hubei University, Wuhan, Hubei (China)]. E-mail: dxliu001@yahoo.com

2007-07-13

317

Adhesiveness of human uterine epithelial RL95-2 cells to trophoblast: Rho protein regulation  

Microsoft Academic Search

Embryo implantation involves adhesion of trophoblast cells to the epithelial lining of the endometrium. Using an in-vitro model to simulate this initial interaction, we previously reported that attachment of human trophoblast-like JAR spheroids to human uterine epithelial RL95-2 cells provokes a Ca2 influx in RL95-2 cells depending on apically localized integrin receptors. Here, we demonstrate that adhesiveness of RL95-2 cells

Carola Heneweer; Lars Hendric Kruse; Felix Kindhauser; Martina Schmidt; Karl H. Jakobs; Hans-Werner Denker; Michael Thie

2002-01-01

318

Effect of various surface treatment for enhancing adhesion of Au on parylene coated protein chip  

Microsoft Academic Search

We describe a method for enhancing adhesion of Au on parylene-c coated surfaces For the ion-beam and plasma effect for enhancing surface energy, ion beam treatment and atmosphere plasma treatment were performed for the modification from hydrophobic to hydrophilic surface, piranha, PBST and BSA treatment were performed Tape-test analysis and piranha treatment were used for qualitative adhesive comparison of Au

K. S. Hwang; J. H. Lee; J. H. Park; T. S. Kim

2003-01-01

319

Insulin-Regulated Increase of Soluble Vascular Adhesion Protein-1 in Diabetes  

PubMed Central

Vascular adhesion protein-1 (VAP-1) is one of the molecules on the endothelial cell membrane, which may guide inflammatory cells into atherosclerotic lesions. This dual function molecule may also contribute to the pathogenesis of atherosclerosis and other vasculopathies via its enzymatic activity that oxidizes primary amines to produce their corresponding aldehydes, hydrogen peroxide, and ammonium. Because VAP-1 also exists in a soluble form, we analyzed its potential usefulness as a biomarker to monitor and predict the extent of ongoing atherosclerotic processes. Soluble VAP-1 (sVAP-1) levels were determined from the sera of 136 Finnish men with established coronary heart disease and in 275 controls using sandwich enzyme immunoassays and correlated to multiple risk factors for coronary events. Intriguingly, sVAP-1 showed a statistically significant correlation with diabetes in both cohorts. We then collected patients with type 1 diabetes and observed that sVAP-1 levels were highly elevated when the patients were metabolically compromised. On normalization of their blood glucose and ketone body levels by exogenous insulin, their sVAP-1 concentration rapidly decreased to control levels. Intravenous glucose tolerance and hyperinsulinemic clamp tests further showed that elevation of blood glucose per se did not increase sVAP-1 levels, but rather, sVAP-1 was inversely correlated with circulating insulin concentrations. In conclusion insulin appears to regulate shedding or clearance of VAP-1, and an increase in sVAP-1 because of absolute or relative insulin deficiency may be directly involved in the pathogenesis of diabetic angiopathy.

Salmi, Marko; Stolen, Craig; Jousilahti, Pekka; Yegutkin, Gennady G.; Tapanainen, Paivi; Janatuinen, Tuula; Knip, Mikael; Jalkanen, Sirpa; Salomaa, Veikko

2002-01-01

320

Localization of Vascular Adhesion Protein-1 (VAP-1) in the Human Eye  

PubMed Central

Recently we showed a critical role for Vascular Adhesion Protein-1 (VAP-1) in rodents during acute ocular inflammation, angiogenesis, and diabetic retinal leukostasis. However, the expression of VAP-1 in the human eye is unknown. VAP-1 localization was investigated by immunohistochemistry. Five ?m thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs against VAP-1 (5?g/ml), smooth muscle actin (1?g/ml), CD31 or isotype-matched IgG at 4°C. Subsequently, a secondary mAb was used for 30min at room temperature, followed by Dako Envision + HRP (AEC) System for signal detection. The stained sections were examined using light microscopy and the signal intensity was quantified by two masked evaluators and graded into 4 discrete categories. In all examined ocular tissues, VAP-1 staining was confined to the vasculature. VAP-1 labeling showed the highest intensity in both arteries and veins of neuronal tissues; retina, and optic nerve, and the lowest intensity in the iris vasculature (p<0.05). Scleral and choroidal vessels showed moderate staining for VAP-1. VAP-1 intensity was significantly higher in the arteries compared to veins (p<0.05). Furthermore, VAP-1 staining in arteries co-localized with both CD31 and smooth muscle actin (sm-actin) staining, suggesting expression of VAP-1 in endothelial cells, smooth muscle cells or potentially pericytes. In conclusion, Immunohistochemistry reveals constitutive expression of VAP-1 in human ocular tissues. VAP-1 expression is exclusive to the vasculature with arteries showing significantly higher expression than veins. Furthermore, VAP-1 expression in the ocular vasculature is heterogeneous, with the vessels of the optic nerve and the retina showing highest expressions. These results characterize VAP-1 expression in human ocular tissues.

Almulki, Lama; Noda, Kousuke; Nakao, Shintaro; Hisatomi, Toshio; Thomas, Kennard L.; Hafezi-Moghadam, Ali

2009-01-01

321

Diversity in the thrombospondin-related adhesive protein gene (TRAP) of Plasmodium vivax.  

PubMed

We analyzed 22 clinical isolates of Plasmodium vivax from Thailand and 17 from Brazil to investigate the extent of sequence variation in the thrombospondin-related adhesive protein of Plasmodium vivax (PvTRAP), a homologue of P. falciparum TRAP (PfTRAP) which has been considered to be a promising vaccine candidate. In total 54 haplotypes were identified from 73 distinct gene clones. Coexistence of different PvTRAP in circulation occurred in 10 and 13 isolates from Thailand and Brazil, respectively. Forty out of 48 substituted nucleotides are non-synonymous changes. Most of the substituted residues reside in the von Willebrand factor type A-domain (region II), a sulfated glycosaminoglycan-binding domain (region III) and a proline-rich region (region IV). All nucleotide substitutions are dimorphic. Two haplotypes from Thailand contain an inserted sequence encoding aspartic acid-serine-proline in the proline-rich region. Sequence analysis has revealed that nucleotide diversity in PvTRAP is low although Brazilian isolates display a higher degree of variation than those from Thailand. Phylogenetic construction using the neighbor joining method has shown that most of the Thai and the Brazilian isolates appear to be mainly clustered into distinct groups. Significantly greater than expected values of the mean number of non-synonymous (d(n)) than synonymous (d(s)) nucleotide substitutions per site were observed in regions II and III of PvTRAP. Analysis of the published PfTRAP sequences has shown a similar finding in regions II and IV suggesting that positive selection operates on the regions. Hence, different regions in PvTRAP and PfTRAP could be under different pressures in terms of immune selection, structural and/or functional constraints. PMID:11368905

Putaporntip, C; Jongwutiwes, S; Tia, T; Ferreira, M U; Kanbara, H; Tanabe, K

2001-05-01

322

Reaction of Vascular Adhesion Protein-1 (VAP-1) with Primary Amines  

PubMed Central

Human vascular adhesion protein-1 (VAP-1) is an endothelial copper-dependent amine oxidase involved in the recruitment and extravasation of leukocytes at sites of inflammation. VAP-1 is an important therapeutic target for several pathological conditions. We expressed soluble VAP-1 in HEK293 EBNA1 cells at levels suitable for detailed mechanistic studies with model substrates. Using the model substrate benzylamine, we analyzed the steady-state kinetic parameters of VAP-1 as a function of solution pH. We found two macroscopic pKa values that defined a bell-shaped plot of turnover number kcat,app as a function of pH, representing ionizable groups in the enzyme-substrate complex. The dependence of (kcat/Km)app on pH revealed a single pKa value (?9) that we assigned to ionization of the amine group in free benzylamine substrate. A kinetic isotope effect (KIE) of 6 to 7.6 on (kcat/Km)app over the pH range of 6 to 10 was observed with d2-benzylamine. Over the same pH range, the KIE on kcat was found to be close to unity. The unusual KIE values on (kcat/Km)app were rationalized using a mechanistic scheme that includes the possibility of multiple isotopically sensitive steps. We also report the analysis of quantitative structure-activity relationships (QSAR) using para-substituted protiated and deuterated phenylethylamines. With phenylethylamines we observed a large KIE on kcat,app (8.01 ± 0.28 with phenylethylamine), indicating that C–H bond breakage is limiting for 2,4,5-trihydroxyphenylalanine quinone reduction. Poor correlations were observed between steady-state rate constants and QSAR parameters. We show the importance of combining KIE, QSAR, and structural studies to gain insight into the complexity of the VAP-1 steady-state mechanism.

Heuts, Dominic P. H. M.; Gummadova, Jennet O.; Pang, Jiayun; Rigby, Stephen E. J.; Scrutton, Nigel S.

2011-01-01

323

Amalgam, an axon guidance Drosophila adhesion protein belonging to the immunoglobulin superfamily: over-expression, purification and biophysical characterization.  

PubMed

Amalgam, a multi-domain member of the immunoglobulin superfamily, possesses homophilic and heterophilic cell adhesion properties. It is required for axon guidance during Drosophila development in which it interacts with the extracellular domain of the transmembrane protein, neurotactin, to promote adhesion. Amalgam was heterologously expressed in Pichia pastoris, and the secreted protein product, bearing an NH(2)-terminal His(6)Tag, was purified from the growth medium by metal affinity chromatography. Size exclusion chromatography separated the purified protein into two fractions: a major, multimeric fraction and a minor, dimeric one. Two protocols to reduce the percentage of multimers were tested. In one, protein induction was performed in the presence of the zwitterionic detergent CHAPS, yielding primarily the dimeric form of amalgam. In a second protocol, agitation was gradually reduced during the course of the induction and antifoam was added daily to reduce the air/liquid interfacial foam area. This latter protocol lowered the percentage of multimer 2-fold, compared to constant agitation. Circular dichroism measurements showed that the dimeric fraction had a high beta-sheet content, as expected for a protein with an immunoglobulin fold. Dynamic light scattering and sedimentation velocity measurements showed that the multimeric fraction displays a monodisperse distribution, with R(H)=16 nm. When co-expressed together with amalgam the ectodomain of neurotactin copurified with it. Furthermore, both purified fractions of amalgam were shown to interact with Torpedo californica acetylcholinesterase, a structural homolog of neurotactin. PMID:18938249

Zeev-Ben-Mordehai, Tzviya; Paz, Aviv; Peleg, Yoav; Toker, Lilly; Wolf, Sharon G; Rydberg, Edwin H; Sussman, Joel L; Silman, Israel

2008-10-08

324

The impact of dendrimer-grafted modifications to model silicon surfaces on protein adsorption and bacterial adhesion.  

PubMed

In the oral cavity, omnipresent salivary protein films (pellicle) mediate bacterial adhesion and biofilm formation on natural tissues as well as on artificial implant surfaces, which may cause serious infectious diseases like periimplantitis. The purpose of this in vitro study was to investigate the adsorption/desorption behaviour of human saliva on model surfaces grafted with polyamidoamine (PAMAM) dendrimer molecules compared to self-assembled monolayers (SAMs) exhibiting the same terminal functions (-NH(2), -COOH) by two complementary analytical methods. Furthermore, the role of saliva conditioning of PAMAM and analogous SAM modifications on the adhesion of Streptococcus gordonii DL1, an early oral colonizer, was investigated. In contrast to SAMs, PAMAM-grafted surfaces showed reduced streptococcal adherence in the absence of pre-adsorbed saliva similar to the level obtained for poly(ethylene glycol) (PEG) coatings. Moreover, coatings of PAMAM-NH(2) maintained their bacteria-repellent behaviour even after saliva-conditioning. As a general outcome, it was found that lower amounts of protein adsorbed on PAMAM coatings than on analogous SAMs. Since this study demonstrates that covalently bound PAMAM dendrimers can modulate the oral bacterial response, this approach has significant potential for the development of anti-adhesive biomaterial surfaces that are conditioned with proteinaceous films. PMID:21906807

Eichler, Mirjam; Katzur, Verena; Scheideler, Lutz; Haupt, Michael; Geis-Gerstorfer, Juergen; Schmalz, Gottfried; Ruhl, Stefan; Müller, Rainer; Rupp, Frank

2011-09-08

325

Exploring the Molecular Origins of Bio(in)compatibility: Adhesion Between Proteins and Individual Chains of Poly(ethylene oxide)  

NASA Astrophysics Data System (ADS)

A critical determinant of the biocompatibility of implanted blood-contacting devices is the initial noncovalent adsorption of blood plasma proteins onto the biomaterial surface. Using high-resolution force spectroscopy, we have measured the complex intermolecular interaction forces between individual end-grafted PEO chains and a probe tip covalently bound with human serum albumin, the most abundant blood plasma protein in the human body. On approach, a long-range, nonlinear repulsive force is observed. Upon retraction, however, adhesion between the HSA probe tip and PEO chain occurs, which in many cases is strong enough to allow long-range adhesion and stretching of the individual PEO chains. The known PEO strain-induced conformational transition from the helical (ttg) to the planar (ttt) conformation is clearly observed and seen to shift to lower force values. Statistical analysis of adhesion data, comparison to a variety of control experiments, and theoretical modeling enable us to interpret these experimental results in terms of electrostatic interactions, hydrogen bonding, and steric forces.

Rixman, Monica A.; Ortiz, Christine

2002-03-01

326

Ras guanyl nucleotide releasing protein 2 affects cell viability and cell-matrix adhesion in ECV304 endothelial cells.  

PubMed

Ras guanyl nucleotide releasing proteins (RasGRPs) are guanine nucleotide exchange factors that activate Ras and Rap. We recently reported that xrasgrp2, which is a homolog of the human rasgrp2, plays a role in vasculogenesis and/or angiogenesis during early development of Xenopus embryos. However, the function of RasGRP2 in human vascular endothelium remains unknown. Therefore we aimed to analyze the function of human RasGRP2 in vascular endothelial cells. RasGRP2 overexpression did not increase Ras activation. However, it slightly increased Ras expression and increased proliferation in ECV304 cells. Furthermore, RasGRP2 overexpression increased Rap1 activation and cell-matrix adhesion in ECV304 cells. These data demonstrate that RasGRP2 increases cell viability and cell-matrix adhesion through increased Ras expression and Rap1 activation, respectively, in endothelial cells. PMID:23563504

Takino, Junichi; Nagamine, Kentaro; Hori, Takamitsu

2013-04-05

327

The Leu-Arg-Glu (LRE) adhesion motif in proteins of the neuromuscular junction with special reference to proteins of the carboxylesterase/cholinesterase family.  

PubMed

Short linear motifs confer evolutionary flexibility on proteins as they can be added with relative ease allowing the acquisition of new functions. Such motifs may mediate a variety of signalling functions. The adhesion-mediating Leu-Arg-Glu (LRE) motif is enriched in laminin beta 2, and has been observed in other proteins, including members of the carboxylesterase/cholinesterase family. It acts as a stop signal for growing axons in the developing neuromuscular junction, binding to the voltage-gated calcium channel. In this bioinformatic analysis, we have investigated the presence of the motif in proteins of the neuromuscular junction, and have also examined its structural position and potential for ligand interaction, as well as phylogenetic conservation, in the carboxylesterase/cholinesterase family. The motif was observed to occur with a significantly higher frequency than expected in the UniProt/Swiss-Prot database, as well as in four individual species (human, mouse, Caenorhabditis elegans and Drosophila melanogaster). Examination of its presence in neuromuscular junction proteins showed it to be enriched in certain proteins of the synaptic basement membrane, including laminin, agrin, acetylcholinesterase and tenascin. A highly significant enrichment was observed in cytoskeletal proteins, particularly intermediate filament proteins and members of the spectrin family. In the carboxylesterase/cholinesterase family, the motif was observed in four conserved positions in the protein structure. It is present in the majority of mammalian acetylcholinesterases, as well as acetylcholinesterases from electric fish and a number of invertebrates. In insects, it is present in the ace-2, rather than in the synaptic ace-1, enzyme. It is also observed in the cholinesterase-like adhesion molecules (neuroligins, neurotactin and glutactin). It is never seen in butyrylcholinesterases, which do not mediate cell adhesion. In conclusion, the significant enrichment of the motif in certain classes of protein, as well as its conserved presence and structural positioning in one protein family, suggests that it has specific functions both in cell adhesion in the neuromuscular junction and in maintaining the structural integrity of the cytoskeleton. PMID:23850873

Johnson, Glynis; Moore, Samuel W

2013-06-10

328

Human Antibodies Specific for the High-Molecular-Weight Adhesion Proteins of Nontypeable Haemophilus influenzae Mediate Opsonophagocytic Activity  

PubMed Central

The HMW1- and HMW2-like adhesion proteins of nontypeable Haemophilus influenzae are expressed by 75% of these strains, and antibodies directed against these proteins are protective in animal models of infection. The purpose of the present study was to define the functional activity of human antibodies specific for these proteins in an in vitro complement-dependent opsonophagocytic assay. Human promyelocytic cell line HL-60 served as the source of phagocytic cells, and a commercial preparation of intravenous immunoglobulin (IVIG) served as the source of human antibodies. High-molecular-weight (HMW) proteins were purified from four prototype nontypeable H. influenzae strains and used to prepare solid-phase affinity columns. IVIG was adsorbed on each column to remove strain-specific anti-HMW antibodies and to allow recovery of affinity-purified anti-HMW antibody fractions. Unadsorbed IVIG killed each of the prototype strains at titers of 1:80 to 1:320. HMW-adsorbed sera demonstrated fourfold decreases in opsonophagocytic titer against the homologous strains compared to unadsorbed IVIG. Affinity-purified anti-HMW antibody preparations demonstrated opsonophagocytic titers of 1:20 to 1:80 against the respective homologous strains and opsonophagocytic titers as high as 1:80 against heterologous strains. None of the affinity-purified anti-HMW antibody preparations was opsonophagocytic for a representative nontypeable H. influenzae strain that did not express HMW1- or HMW2-like proteins. These data demonstrate that human antibodies specific for the HMW1/HMW2-like adhesion proteins of nontypeable H. influenzae are opsonophagocytic and that such antibodies recognize epitopes shared by the HMW proteins of unrelated nontypeable H. influenzae strains. These results argue for continued investigation of the HMW1/HMW2-like proteins as potential vaccine candidates for prevention of disease due to nontypeable H. influenzae.

Winter, Linda E.; Barenkamp, Stephen J.

2003-01-01

329

Identification, characterization, and expression levels of putative adhesive proteins from the tube-dwelling polychaete Sabellaria alveolata.  

PubMed

The shelter of the tube-dwelling polychaete Sabellaria alveolata is composed of mineral particles assembled with spots of a proteinaceous cement. The adhesive proteins constituting the cement were identified on the basis of their sequence similarity with proteins of a phylogenetically related species, Phragmatopoma californica. Two positively charged proteins, Sa-1 and Sa-2, share common features: they both have a mass of 22 kDa; are rich in glycine, tyrosine and basic residues; and show repeated peptide motifs. The consensus repeat of Sa-1 is KGAYGAKGLGYGNKAGYGAYG (occurring 6-8 times), while Sa-2 displays the consensus heptapeptide VHKAAWG (5 times) and undecapeptide VHKAAGYGGYG (8 times). Two variants of a serine-rich protein, Sa-3A (22 kDa) and Sa-3B (21 kDa), were also identified. Their serine residues account for 75 mol% and are probably phosphorylated, meaning that Sa-3 is very acidic and negatively charged. Moreover, tyrosine residues of all adhesive proteins are presumably modified into DOPA. Although protein sequences are not well-conserved between S. alveolata and P. californica, their main characteristics (including amino acid composition, post-translational modifications, repeated patterns, isoelectric point, and mass) are shared by both species. This suggests that these features are more important for their function than the primary structure of the proteins. The mRNA abundance for each protein was estimated by quantitative real-time PCR, revealing relative expression levels of about 5, 11, 1.5, and 1 for Sa-1, -2, -3A, and -3B, respectively. These levels could be indicative of charge neutralization phenomena or could reflect their function (interface vs. bulk) in the cement. PMID:23111133

Becker, Pierre T; Lambert, Aurélie; Lejeune, Annabelle; Lanterbecq, Déborah; Flammang, Patrick

2012-10-01

330

Purification of neuronal cell surface proteins and generation of epitope-specific monoclonal antibodies against cell adhesion molecules.  

PubMed

To establish a procedure for the purification of a broad spectrum of cell surface proteins, three separate methods based on different principles were compared with the aid of four marker proteins. Membrane preparation by sedimentation-flotation centrifugation, temperature-induced phase separation with Triton X-114, and lectin affinity chromatography were used separately as well as in combination. The two-step procedure of membrane preparation and lectin affinity chromatography provided by far the best enrichment of cell surface marker proteins. This result was further substantiated by screening greater than 6,600 hybridoma cultures that originated from mice that had been immunized with protein fractions obtained by different purification protocols. In addition, it was found that solubilized glycoproteins used as immunogens led to many more cell surface-specific monoclonal antibodies than glycoproteins immobilized on lectin-agarose beads. Three monoclonal antibodies that recognize distinct epitopes of cell adhesion molecules (CAMs) were isolated. Monoclonal antibody C4 bound to a detergent-labile epitope of G4 (neuron-glia CAM). Monoclonal antibody D1 recognized specifically nonreduced neural CAM (N-CAM) with intact disulfide bridges, and monoclonal antibody D3 recognized only the 180-kilodalton isoform of N-CAM. Because of these specificities, these monoclonal antibodies promise to be useful tools for the elucidation of the structural organization of adhesion molecules. PMID:2462022

Schlosshauer, B

1989-01-01

331

Activation of Rho-Dependent Cell Spreading and Focal Adhesion Biogenesis by the v-Crk Adaptor Protein  

PubMed Central

The small GTPase RhoA plays a critical role in signaling pathways activated by serum-derived factors, such as lysophosphatidic acid (LPA), including the formation of stress fibers in fibroblasts and neurite retraction and rounding of soma in neuronal cells. Previously, we have shown that ectopic expression of v-Crk, an SH2/SH3 domain-containing adapter proteins, in PC12 cells potentiates nerve growth factor (NGF)-induced neurite outgrowth and promotes the survival of cells when NGF is withdrawn. In the present study we show that, when cultured in 15% serum or lysophosphatidic acid-containing medium, the majority of v-Crk-expressing PC12 cells (v-CrkPC12 cells) display a flattened phenotype with broad lamellipodia and are refractory to NGF-induced neurite outgrowth unless serum is withdrawn. v-Crk-mediated cell flattening is inhibited by treatment of cells with C3 toxin or by mutation in the Crk SH2 or SH3 domain. Transient cotransfection of 293T cells with expression plasmids for p160ROCK (Rho-associated coiled-coil-containing kinase) and v-Crk, but not SH2 or SH3 mutants of v-Crk, results in hyperactivation of p160ROCK. Moreover, the level of phosphatidylinositol-4,5-bisphosphate is increased in v-CrkPC12 cells compared to the levels in mutant v-Crk-expressing cells or wild-type cells, consistent with PI(4)P5 kinase being a downstream target for Rho. Expression of v-Crk in PC12 cells does not result in activation of Rac- or Cdc42-dependent kinases PAK and S6 kinase, demonstrating specificity for Rho. In contrast to native PC12 cells, in which focal adhesions and actin stress fibers are not observed, immunohistochemical analysis of v-CrkPC12 cells reveals focal adhesion complexes which are formed at the periphery of the cell and are connected to actin cables. The formation of focal adhesions correlates with a concomitant upregulation in the expression of focal adhesion proteins FAK, paxillin, ?3-integrin, and a higher-molecular-weight form of ?1-integrin. Our results indicate that v-Crk activates the Rho-signaling pathway and serves as a scaffolding protein during the assembly of focal adhesions in PC12 cells.

Altun-Gultekin, Zeynep F.; Chandriani, Sanjay; Bougeret, Cecile; Ishizaki, Toshimasa; Narumiya, Shuh; de Graaf, Petra; Van Bergen en Henegouwen, Paul; Hanafusa, Hidesaburo; Wagner, John A.; Birge, Raymond B.

1998-01-01

332

Organ-specific function of adhesion G protein-coupled receptor GPR126 is domain-dependent.  

PubMed

Despite their abundance and multiple functions in a variety of organ systems, the function and signaling mechanisms of adhesion G protein-coupled receptors (GPCRs) are poorly understood. Adhesion GPCRs possess large N termini containing various functional domains. In addition, many of them are autoproteolytically cleaved at their GPS sites into an N-terminal fragment (NTF) and C-terminal fragment. Here we demonstrate that Gpr126 is expressed in the endocardium during early mouse heart development. Gpr126 knockout in mice and knockdown in zebrafish caused hypotrabeculation and affected mitochondrial function. Ectopic expression of Gpr126-NTF that lacks the GPS motif (NTF(?GPS)) in zebrafish rescued the trabeculation but not the previously described myelination phenotype in the peripheral nervous system. These data support a model in which the NTF of Gpr126, in contrast to the C-terminal fragment, plays an important role in heart development. Collectively, our analysis provides a unique example of the versatile function and signaling properties of adhesion GPCRs in vertebrates. PMID:24082093

Patra, Chinmoy; van Amerongen, Machteld J; Ghosh, Subhajit; Ricciardi, Filomena; Sajjad, Amna; Novoyatleva, Tatyana; Mogha, Amit; Monk, Kelly R; Mühlfeld, Christian; Engel, Felix B

2013-09-30

333

Flagellar adhesion between mating type plus and mating type minus gametes activates a flagellar protein-tyrosine kinase during fertilization in Chlamydomonas.  

PubMed

When Chlamydomonas gametes of opposite mating type are mixed together, flagellar adhesion through sex-specific adhesion molecules triggers a transient elevation of intracellular cAMP, leading to gamete activation in preparation for cell-cell fusion and zygote formation. Here, we have identified a protein-tyrosine kinase (PTK) activity that is stimulated by flagellar adhesion. We determined that the protein-tyrosine kinase inhibitor genistein inhibited fertilization, and that fertilization was rescued by dibutyryl cAMP, indicating that the genistein-sensitive step was upstream of the increase in cAMP. Incubation with ATP of flagella isolated from non-adhering and adhering gametes followed by SDS-PAGE and immunoblotting with anti-phosphotyrosine antibodies showed that adhesion activated a flagellar PTK that phosphorylated a 105-kDa flagellar protein. Assays using an exogenous protein-tyrosine kinase substrate confirmed that the activated PTK could be detected only in flagella isolated from adhering gametes. Our results indicate that stimulation of the PTK is a very early event during fertilization. Activation of the PTK was blocked when gametes underwent flagellar adhesion in the presence of the protein kinase inhibitor staurosporine, but not in the presence of the cyclic nucleotide-dependent protein kinase inhibitor, H8, which (unlike staurosporine) does not block the increases in cAMP. In addition, incubation of gametes of a single mating type in dibutyryl cAMP failed to activate the PTK. Finally, flagella adhesion between plus and minus fla10-1 gametes, which have a temperature-sensitive lesion in the microtubule motor protein kinesin-II, failed to activate the PTK at elevated temperatures. Our results show that kinesin-II is essential for coupling flagellar adhesion to activation of a flagellar PTK and cAMP generation during fertilization in Chlamydomonas. PMID:12821679

Wang, Qian; Snell, William J

2003-06-23

334

[The role of the ERM protein family in maintaining cellular polarity, adhesion and regulation of cell motility].  

PubMed

Ezrin, radixin and moesin, forming the ERM protein family, act as molecular crosslinkers between actin filaments and proteins anchored in the cell membrane. By participating in a complex intracellular network of signal transduction pathways, ERM proteins play a key role in the regulation of adhesion and polarity of normal cells through interactions with membrane molecules, e.g. E-cadherin. Dynamic cytoskeletal transformations, in which the ERM and Rho GTPases are involved, lead to the formation of membrane-cytoplasmic structures, such as filopodia and lamellipodia, which are responsible for cellular motility. The interactions of ERM proteins with active Akt kinase cause the acquisition of antiapoptotic cellular features by downregulation of the proapoptotic protein Bad. ERM protein activity is regulated by phosphorylation/dephosphorylation reactions and linking phosphatidylinositols. The model of activation based on the molecular conformation changes by breaking the intramolecular bonds and exposing actin binding sites is essential for the proper functioning of the ERM proteins. Additionally, the connection types between the ERM and membrane proteins (direct or indirect by EBP50 and E3KARP) play an important role in transduction of signals from the extracellular matrix. Due to the wide range of ezrin, radixin and moesin cytophysiological features, detailed exploration of the ERM biochemistry will provide a series of answers to questions about ambiguous functions in many intracellular signal transduction pathways. PMID:22470191

Ha?o?, Agnieszka; Donizy, Piotr

2012-03-27

335

The novel actin/focal adhesion-associated protein MISP is involved in mitotic spindle positioning in human cells.  

PubMed

Accurate mitotic spindle positioning is essential for the regulation of cell fate choices, cell size and cell position within tissues. The most prominent model of spindle positioning involves a cortical pulling mechanism, where the minus end-directed microtubule motor protein dynein is attached to the cell cortex and exerts pulling forces on the plus ends of astral microtubules that reach the cortex. In nonpolarized cultured cells integrin-dependent, retraction fiber-mediated cell adhesion is involved in spindle orientation. Proteins serving as intermediaries between cortical actin or retraction fibers and astral microtubules remain largely unknown. In a recent genome-wide RNAi screen we identified a previously uncharacterized protein, MISP (C19ORF21) as being involved in centrosome clustering, a process leading to the clustering of supernumerary centrosomes in cancer cells into a bipolar mitotic spindle array by microtubule tension. Here, we show that MISP is associated with the actin cytoskeleton and focal adhesions and is expressed only in adherent cell types. During mitosis MISP is phosphorylated by Cdk1 and localizes to retraction fibers. MISP interacts with the +TIP EB1 and p150(glued), a subunit of the dynein/dynactin complex. Depletion of MISP causes mitotic arrest with reduced tension across sister kinetochores, chromosome misalignment and spindle multipolarity in cancer cells with supernumerary centrosomes. Analysis of spindle orientation revealed that MISP depletion causes randomization of mitotic spindle positioning relative to cell axes and cell center. Together, we propose that MISP links microtubules to the actin cytoskeleton and focal adhesions in order to properly position the mitotic spindle. PMID:23574715

Maier, Bettina; Kirsch, Michael; Anderhub, Simon; Zentgraf, Hanswalter; Krämer, Alwin

2013-04-10

336

Focal Adhesion Kinase Suppresses Apoptosis by Binding to the Death Domain of Receptor-Interacting Protein  

Microsoft Academic Search

Tumor cells resist the apoptotic stimuli associated with invasion and metastasis by activating survival signals that suppress apoptosis. Focal adhesion kinase (FAK), a tyrosine kinase that is overexpressed in a variety of human tumors, mediates one of these survival signals. Attenuation of FAK expression in tumor cells results in apoptosis that is mediated by caspase 8- and FADD-dependent pathways, suggesting

Elena Kurenova; Li-Hui Xu; Xihui Yang; Albert S. Baldwin; Rolf J. Craven; Steven K. Hanks; Zheng-gang Liu; William G. Cance

2004-01-01

337

Adhesion of endothelial cells and adsorption of serum proteins on gas plasma-treated polytetrafluoroethylene  

Microsoft Academic Search

From in vitro experiments it is known that human endothelial cells show poor adhesion to hydrophobic polymers. The hydrophobicity of vascular prostheses manufactured from Teflon® or Dacron® may be the reason why endothelialization of these grafts does not occur after implantation in humans. We modified films of polytetrafluoroethylene (Teflon®) by nitrogen plasma and oxygen plasma treatments to make the surfaces

A. Dekker; K. Reitsma; T. Beugeling; A. Bantjes; J. Feijen; Aken van W. G

1991-01-01

338

Floc stability and adhesion of green-fluorescent-protein-marked bacteria to flocs in activated sludge  

Microsoft Academic Search

Wastewater is often treated using the activated sludge process. Flocculation and subsequent sedimentation of flocs are vital steps in this process that have direct influence on the quality of the effluent water from wastewater treatment plants. Since cells that remain free-living will decrease the quality of the effluent water it is important to understand the mechanisms of bacterial adhesion to

Ann-Cathrin Olofsson; Anna Zita; Malte Hermansson

1998-01-01

339

Reduced expression of the adhesion protein tensin1 in cultured human dermal fibroblasts affects collagen gel contraction.  

PubMed

As revealed by immunohistochemistry and RT-QPCR, the focal adhesion protein tensin1 is expressed in cultured human dermal fibroblasts and reduced by 60% after transfection with tensin1 siRNA. Tensin1 silenced fibroblast exhibited a strongly reduced capacity to contract collagen gels. Aged fibroblasts, generated with the Hayflick replicative senescence model, exhibit as siRNA silences fibroblasts, a reduced tensin1 expression and an impaired gel contraction capacity. Based on these results, we speculate that in human dermal fibroblasts, tensin1 plays an important role in cell-matrix interaction and that a reduced expression might contribute to the dermal alterations observed during skin ageing. PMID:18537817

Saintigny, Gaëlle; Bernard, François-Xavier; Juchaux, Franck; Pedretti, Nathalie; Mahé, Christian

2008-06-04

340

Cross Talk between Cell Cell and Cell Matrix Adhesion Signaling Pathways during Heart Organogenesis: Implications for Cardiac Birth Defects  

NASA Astrophysics Data System (ADS)

The anterior posterior and dorsal ventral progression of heart organogenesis is well illustrated by the patterning and activity of two members of different families of cell adhesion molecules: the calcium-dependent cadherins, specifically N-cadherin, and the extracellular matrix glycoproteins, fibronectin. N-cadherin by its binding to the intracellular molecule [beta]-catenin and fibronectin by its binding to integrins at focal adhesion sites, are involved in regulation of gene expression by their association with the cytoskeleton and through signal transduction pathways. The ventral precardiac mesoderm cells epithelialize and become stably committed by the activation of these cell matrix and intracellular signaling transduction pathways. Cross talk between the adhesion signaling pathways initiates the characteristic phenotypic changes associated with cardiomyocyte differentiation: electrical activity and organization of myofibrils. The development of both organ form and function occurs within a short interval thereafter. Mutations in any of the interacting molecules, or environmental insults affecting either of these signaling pathways, can result in embryonic lethality or fetuses born with severe heart defects. As an example, we have defined that exposure of the embryo temporally to lithium during an early sensitive developmental period affects a canonical Wnt pathway leading to [beta]-catenin stabilization. Lithium exposure results in an anterior posterior progression of severe cardiac defects.

Linask, Kersti K.; Manisastry, Shyam; Han, Mingda

2005-06-01

341

Identification, purification, and characterization of a zyxin-related protein that binds the focal adhesion and microfilament protein VASP (vasodilator-stimulated phosphoprotein).  

PubMed Central

VASP (vasodilator-stimulated phosphoprotein), an established substrate of cAMP- and cGMP-dependent protein kinases in vitro and in living cells, is associated with focal adhesions, microfilaments, and membrane regions of high dynamic activity. Here, the identification of an 83-kDa protein (p83) that specifically binds VASP in blot overlays of different cell homogenates is reported. With VASP overlays as a detection tool, p83 was purified from porcine platelets and used to generate monospecific polyclonal antibodies. VASP binding to purified p83 in solid-phase binding assays and the closely matching subcellular localization in double-label immunofluorescence analyses demonstrated that both proteins also directly interact as native proteins in vitro and possibly in living cells. The subcellular distribution, the biochemical properties, as well as microsequencing data revealed that porcine platelet p83 is related to chicken gizzard zyxin and most likely represents the mammalian equivalent of the chicken protein. The VASP-p83 interaction may contribute to the targeting of VASP to focal adhesions, microfilaments, and dynamic membrane regions. Together with our recent identification of VASP as a natural ligand of the profilin poly-(L-proline) binding site, our present results suggest that, by linking profilin to zyxin/p83, VASP may participate in spatially confined profilin-regulated F-actin formation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 6

Reinhard, M; Jouvenal, K; Tripier, D; Walter, U

1995-01-01

342

Glyceraldehyde-3-Phosphate Dehydrogenase of Paracoccidioides brasiliensis Is a Cell Surface Protein Involved in Fungal Adhesion to Extracellular Matrix Proteins and Interaction with Cells  

PubMed Central

The pathogenic fungus Paracoccidioides brasiliensis causes paracoccidioidomycosis, a pulmonary mycosis acquired by inhalation of fungal airborne propagules, which may disseminate to several organs and tissues, leading to a severe form of the disease. Adhesion to and invasion of host cells are essential steps involved in the infection and dissemination of pathogens. Furthermore, pathogens use their surface molecules to bind to host extracellular matrix components to establish infection. Here, we report the characterization of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of P. brasiliensis as an adhesin, which can be related to fungus adhesion and invasion. The P. brasiliensis GAPDH was overexpressed in Escherichia coli, and polyclonal antibody against this protein was obtained. By immunoelectron microscopy and Western blot analysis, GAPDH was detected in the cytoplasm and the cell wall of the yeast phase of P. brasiliensis. The recombinant GAPDH was found to bind to fibronectin, laminin, and type I collagen in ligand far-Western blot assays. Of special note, the treatment of P. brasiliensis yeast cells with anti-GAPDH polyclonal antibody and the incubation of pneumocytes with the recombinant protein promoted inhibition of adherence and internalization of P. brasiliensis to those in vitro-cultured cells. These observations indicate that the cell wall-associated form of the GAPDH in P. brasiliensis could be involved in mediating binding of fungal cells to fibronectin, type I collagen, and laminin, thus contributing to the adhesion of the microorganism to host tissues and to the dissemination of infection.

Barbosa, Monica Santiago; Bao, Sonia Nair; Andreotti, Patricia Ferrari; de Faria, Fabricia P.; Felipe, Maria Sueli S.; dos Santos Feitosa, Luciano; Mendes-Giannini, Maria Jose Soares; de Almeida Soares, Celia Maria

2006-01-01

343

Immunolocalization of keratin-associated beta-proteins in developing epidermis of lizard suggests that adhesive setae contain glycine--cysteine-rich proteins.  

PubMed

The localization of specific keratin-associated beta-proteins (formerly referred to as beta-keratins) in the embryonic epidermis of lizards is not known. Two specific keratin-associated beta-proteins of the epidermis, one representing the glycine-rich subfamily (HgG5) and the other the glycine-cysteine medium-rich subfamily (HgGC10), have been immunolocalized at the ultrastructural level in the lizard Anolis lineatopus. The periderm and granulated subperiderm are most immunonegative for these proteins. HgG5 is low to absent in theOberhäutchen layer while is present in the forming beta-layer, and disappears in mesos- and alpha-layers. Instead, HgGC10 is present in the Oberhäutchen, beta-, and also in the following alpha-layers, and specifically accumulates in the developing adhesive setae but not in the surrounding cells of the clear layer. Therefore, setae and their terminal spatulae that adhere to surfaces allowing these lizards to walk vertically contain cysteine-glycine rich proteins. The study suggests that, like in adult and regenerating epidermis, the HgGC10 protein is not only accumulated in cells of the beta-layer but also in those forming the alpha-layer. This small protein therefore is implicated in resistance, flexibility, and stretching of the epidermal layers. It is also hypothesized that the charges of these proteins may influence adhesion of the setae of pad lamellae. Conversely, glycine-rich beta-proteins like HgG5 give rise to the dense, hydrophobic, and chromophobic corneous material of the resistant beta-layer. This result suggests that the differential accumulation of keratin-associated beta-proteins over the alpha-keratin network determines differences in properties of the stratified layers of the epidermis of lizards. PMID:23108977

Alibardi, Lorenzo

2012-10-29

344

Myxoma viral serpin, Serp-1, inhibits human monocyte adhesion through regulation of actin-binding protein filamin B.  

PubMed

Serp-1 is a secreted myxoma viral serine protease inhibitor (serpin) with proven, highly effective, anti-inflammatory defensive activity during host cell infection, as well as potent immunomodulatory activity in a wide range of animal disease models. Serp-1 binds urokinase-type plasminogen activator (uPA) and the tissue-type PA, plasmin, and factor Xa, requiring uPA receptor (uPAR) for anti-inflammatory activity. To define Serp-1-mediated effects on inflammatory cell activation, we examined the association of Serp-1 with monocytes and T cells, effects on cellular migration, and the role of uPAR-linked integrins and actin-binding proteins in Serp-1 cellular responses. Our results show that Serp-1 associates directly with activated monocytes and T lymphocytes, in part through interaction with uPAR (P<0.001). Serp-1, but not mammalian serpin PA inhibitor-1 (PAI-1), attenuated cellular adhesion to the extracellular matrix. Serp-1 and PAI-1 reduced human monocyte and T cell adhesion (P<0.001) and migration across endothelial monolayers in vitro (P<0.001) and into mouse ascites in vivo (P<0.001). Serp-1 and an inactive Serp-1 mutant Serp-1(SAA) bound equally to human monocytes and T cells, but a highly proinflammatory mutant, Serp-1(Ala(6)), bound less well to monocytes. Serp-1 treatment of monocytes increased expression of filamin B actin-binding protein and reduced CD18 (beta-integrin) expression (P<0.001) in a uPAR-dependent response. Filamin colocalized and co-immunoprecipitated with uPAR, and short interference RNA knock-down of filamin blocked Serp-1 inhibition of monocyte adhesion. We report here that the highly potent, anti-inflammatory activity of Serp-1 is mediated through modification of uPAR-linked beta-integrin and filamin in monocytes, identifying this interaction as a central regulatory axis for inflammation. PMID:19052145

Viswanathan, Kasinath; Richardson, Jakob; Togonu-Bickersteth, Babajide; Dai, Erbin; Liu, Liying; Vatsya, Pracha; Sun, Yun-ming; Yu, Jeff; Munuswamy-Ramanujam, Ganesh; Baker, Henry; Lucas, Alexandra R

2008-12-03

345

Ethanol inhibits L1 cell adhesion molecule activation of mitogen-activated protein kinases  

Microsoft Academic Search

Inhibition of the functions of L1 cell adhesion molecule (L1) by ethanol has been implicated in the pathogenesis of the neu- rodevelopmental aspects of the fetal alcohol syndrome (FAS). Ethanol at pharmacological concentrations has been shown to inhibit L1-mediated neurite outgrowth of rat post-natal day 6 cerebellar granule cells (CGN). Extracellular signal-related kinases (ERK) 1\\/2 activation occurs following L1 clustering.

Ningfeng Tang; Min He; Mary Ann O'Riordan; Chloe Farkas; Kevin Buck; Vance Lemmon; Cynthia F. Bearer

2006-01-01

346

Hydrogen sulfide impairs keratinocyte cell growth and adhesion inhibiting mitogen-activated protein kinase signaling  

Microsoft Academic Search

The effects of exogenous hydrogen sulfide (H2S) on normal skin-derived immortalized human keratinocytes have been investigated in detail. We show in vitro that exogenous hydrogen sulfide reduces clonal growth, cell proliferation and cell adhesion of human keratinocytes. H2S, in fact, decreases the frequency of the putative keratinocyte stem cell subpopulation in culture, consequently affecting clonal growth, and impairs cell proliferation

Giuliana Gobbi; Francesca Ricci; Chiara Malinverno; Cecilia Carubbi; Maurizia Pambianco; Giuseppe de Panfilis; Marco Vitale; Prisco Mirandola

2009-01-01

347

Host Protein Binding and Adhesive Properties of H6 and H7 Flagella of Attaching and Effacing Escherichia coli?  

PubMed Central

It had been suggested that the flagella of enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) might contribute to host colonization. In this study, we set out to investigate the adhesive properties of H7 and H6 flagella. We studied the abilities of EHEC EDL933 (O157:H7) and EPEC E2348/69 (O127:H6) flagella to bind to bovine mucus, host proteins such as mucins, and extracellular matrix proteins. Through several approaches, we found that H6 and H7 flagella and their flagellin monomers bind to mucins I and II and to freshly isolated bovine mucus. A genetic approach showed that EHEC and EPEC fliC deletion mutants were significantly less adherent to bovine intestinal tissue than the parental wild-type strains. In addition, we found that EPEC bacteria and H6 flagella, but not EHEC, bound largely, in a dose-dependent manner, to collagen and to a lesser extent to laminin and fibronectin. We also report that EHEC O157:H7 strains agglutinate rabbit red blood cells via their flagella, a heretofore unknown phenotype in this pathogroup. Collectively, our data demonstrate that the H6 and H7 flagella possess adhesive properties, particularly the ability to bind mucins, that may contribute to colonization of mucosal surfaces.

Erdem, Aysen L.; Avelino, Fabiola; Xicohtencatl-Cortes, Juan; Giron, Jorge A.

2007-01-01

348

Local control of protein binding and cell adhesion by patterned organic thin films.  

PubMed

Control of the cell adhesion and growth on chemically patterned surfaces is important in an increasing number of applications in biotechnology and medicine, for example implants, in-vitro cellular assays, and biochips. This review covers patterning techniques for organic thin films suitable for site-directed guidance of cell adhesion to surfaces. Available surface patterning techniques are critically evaluated, with special emphasis on surface chemistry that can be switched in time and space during cultivation of cells. Examples from the authors' laboratory include the use of cell-repellent self-assembled monolayers (SAM) terminated by oligoethylene glycol (OEG) units and the lifting of the cell repellent properties by use of electrogenerated Br2/HOBr which can be performed with positionable microelectrodes. Structural changes of the SAM were analyzed by polarization-modulated infrared reflection absorption spectroscopy (PM IRRAS). Use of a soft array system of individually addressable microelectrodes enables formation of flexible and complex patterns in a short time and has the potential for further acceleration of probe-induced local manipulation of cell adhesion. PMID:23411629

Meiners, Frank; Plettenberg, Inka; Witt, Julia; Vaske, Britta; Lesch, Andreas; Brand, Izabella; Wittstock, Gunther

2013-02-15

349

Dynamic adhesions and MARCKS in melanoma cells  

PubMed Central

Summary Cell motility necessitates the rapid formation and disassembly of cell adhesions. We have studied adhesions in a highly motile melanoma cell line using various biochemical approaches and microscopic techniques to image close adhesions. We report that WM-1617 melanoma cells contain at least two types of close adhesion: classic focal adhesions and more extensive, irregularly shaped adhesions that tend to occur along lamellipodial edges. In contrast to focal adhesions, these latter adhesions are highly dynamic and can be disassembled rapidly via protein kinase C (PKC) activation (e.g. by eicosanoid) and MARCKS phosphorylation. MARCKS overexpression, however, greatly increases the area of close adhesions and renders them largely refractory to PKC stimulation. This indicates that nonphosphorylated MARCKS is an adhesion stabilizer. Unlike focal adhesions, the dynamic adhesions contain ?3 integrin and MARCKS, but they do not contain the focal adhesion marker vinculin. Overall, these results begin to define the molecular and functional properties of dynamic close adhesions involved in cell motility.

Estrada-Bernal, Adriana; Gatlin, Jesse C.; Sunpaweravong, Somkiat; Pfenninger, Karl H.

2009-01-01

350

Cell contact/adhesion proteins Lgl and DFak56: tumorigenic and whole-organism vital effects studied in Drosophila.  

PubMed

Drosophila modeling can be effectively used for comprehensive and refined analysis of tumorigenesis, including the discovery of therapeutic anti-cancer drugs and their testing [1]. The Drosophila lgl gene was the first animal tumor suppressor found and the first tumor-associated gene encoding cytoplasmic protein. We compared the gene ontology of two cancer associated cytoplasmic proteins, Lgl and DFak56 (ortholog of human focal adhesion kinase, FAK). On the molecular level, both Lgl and FAK are involved in protein binding and the formation of macromolecular complexes mediated by phosphorylation in specific sites. On the cellular level, Lgl and FAK participate in cytoskeletal structure/dynamics, cell/ESM and cell to cell adhesion, and cell/tissue polarity. The biological processes of both genes comprise protein transport, cell signaling, cell motility and proliferation. Surprisingly, we found that diverse lgl*- null variants are widespread in lgl*-/lgl+ haplozygotic state in distant populations. To address this paradox, we found that under permanent thermal stress the developmental viability and the life span of lgl*-/lgl+ heterozygotes increased compared to the control flies. The stress-protective haplo-adaptive effect was maternally mediated and sex-specific, as males are more sensitive. The exposure of virgin haplozygotic females with one functional lgl allele to pulse thermal stress at successive stages of oogenesis showed that the germ line - early oocyte stage appeared most sensitive. Pulse heating of this stage in the parental females with one lgl dose resulted in a transgenerational haplo-adaptive effect on the viability and life span of the next generation animals. These data are important for a comprehensive knowledge of cancer-associated gene effects and evaluation of the aftermath of cancer therapy. PMID:21707508

Weisman, Nataly Ya; Golubovsky, Michael D

2011-09-01

351

The cell-adhesion G protein-coupled receptor BAI3 is a high-affinity receptor for C1q-like proteins.  

PubMed

C1q-like genes (C1ql1-C1ql4) encode small, secreted proteins that are expressed in differential patterns in the brain but whose receptors and functions remain unknown. BAI3 protein, in contrast, is a member of the cell-adhesion class of G protein-coupled receptors that are expressed at high levels in the brain but whose ligands have thus far escaped identification. Using a biochemical approach, we show that all four C1ql proteins bind to the extracellular thrombospondin-repeat domain of BAI3 with high affinity, and that this binding is mediated by the globular C1q domains of the C1ql proteins. Moreover, we demonstrate that addition of submicromolar concentrations of C1ql proteins to cultured neurons causes a significant decrease in synapse density, and that this decrease was prevented by simultaneous addition of the thrombospondin-repeat fragment of BAI3, which binds to C1ql proteins. Our data suggest that C1ql proteins are secreted signaling molecules that bind to BAI3 and act, at least in part, to regulate synapse formation and/or maintenance. PMID:21262840

Bolliger, Marc F; Martinelli, David C; Südhof, Thomas C

2011-01-24

352

The cell-adhesion G protein-coupled receptor BAI3 is a high-affinity receptor for C1q-like proteins  

PubMed Central

C1q-like genes (C1ql1–C1ql4) encode small, secreted proteins that are expressed in differential patterns in the brain but whose receptors and functions remain unknown. BAI3 protein, in contrast, is a member of the cell-adhesion class of G protein-coupled receptors that are expressed at high levels in the brain but whose ligands have thus far escaped identification. Using a biochemical approach, we show that all four C1ql proteins bind to the extracellular thrombospondin-repeat domain of BAI3 with high affinity, and that this binding is mediated by the globular C1q domains of the C1ql proteins. Moreover, we demonstrate that addition of submicromolar concentrations of C1ql proteins to cultured neurons causes a significant decrease in synapse density, and that this decrease was prevented by simultaneous addition of the thrombospondin-repeat fragment of BAI3, which binds to C1ql proteins. Our data suggest that C1ql proteins are secreted signaling molecules that bind to BAI3 and act, at least in part, to regulate synapse formation and/or maintenance.

Bolliger, Marc F.; Martinelli, David C.; Sudhof, Thomas C.

2011-01-01

353

A Novel Group of Moraxella catarrhalis UspA Proteins Mediates Cellular Adhesion via CEACAMs and Vitronectin  

PubMed Central

Moraxella catarrhalis (Mx) is a common cause of otitis media and exacerbation of chronic obstructive pulmonary disease, an increasing worldwide problem. Surface proteins UspA1 and UspA2 of Mx bind to a number of human receptors and may function in pathogenesis. Genetic recombination events in the pathogen can generate hybrid proteins termed UspA2H. However, whether certain key functions (e.g. UspA1-specific CEACAM binding) can be exchanged between these adhesin families remains unknown. In this study, we have shown that Mx can incorporate the UspA1 CEACAM1-binding region not only into rare UspA1 proteins devoid of CEACAM-binding ability, but also into UspA2 which normally lack this capacity. Further, a screen of Mx isolates revealed the presence of novel UspA2 Variant proteins (UspA2V) in ?14% of the CEACAM-binding population. We demonstrate that the expression of UspA2/2V with the CEACAM-binding domain enable Mx to bind both to cell surface CEACAMs and to integrins, the latter via vitronectin. Such properties of UspA2/2V have not been reported to date. The studies demonstrate that the UspA family is much more heterogeneous than previously believed and illustrate the in vivo potential for exchange of functional regions between UspA proteins which could convey novel adhesive functions whilst enhancing immune evasion.

Hill, Darryl J.; Whittles, Cheryl; Virji, Mumtaz

2012-01-01

354

Barnacle settlement and the adhesion of protein and diatom microfouling to xerogel films with varying surface energy and water wettability.  

PubMed

Previous work has shown that organosilica-based xerogels have the potential to control biofouling. In this study, modifications of chemistry were investigated with respect to their resistance to marine slimes and to settlement of barnacle cyprids. Adhesion force measurements of bovine serum albumin (BSA)-coated atomic force microscopy (AFM) tips to xerogel surfaces prepared from aminopropylsilyl-, fluorocarbonsilyl-, and hydrocarbonsilyl-containing precursors, indicated that adhesion was significantly less on the xerogel surfaces in comparison to a poly(dimethylsiloxane) elastomer (PDMSE) standard. The strength of adhesion of BSA on the xerogels was highest on surfaces with the highest and the lowest critical surface tensions, gamma(C) and surface energies, gamma(S), and duplicated the 'Baier curve'. The attachment to and removal of cells of the diatom Navicula perminuta from a similar series of xerogel surfaces were examined. Initial attachment of cells was comparable on all of the xerogel surfaces, but the percentage removal of attached cells by hydrodynamic shear stress increased with gamma(C) and increased wettability as measured by the static water contact angle, theta(Ws), of the xerogel surfaces. The percentage removal of cells of Navicula was linearly correlated with both properties (R(2) = 0.74 for percentage removal as a function of theta(Ws) and R(2) = 0.69 for percentage removal as a function of gamma(C)). Several of the aminopropylsilyl-containing xerogels showed significantly greater removal of Navicula compared to a PDMSE standard. Cypris larvae of the barnacle B. amphitrite showed preferred settlement on hydrophilic/higher energy surfaces. Settlement was linearly correlated with theta(Ws) (R(2) = 0.84) and gamma(C) (R(2) = 0.84). Hydrophilic xerogels should prove useful as coatings for boats in regions where fouling is dominated by microfouling (protein and diatom slimes). PMID:20645195

Finlay, John A; Bennett, Stephanie M; Brewer, Lenora H; Sokolova, Anastasiya; Clay, Gemma; Gunari, Nikhil; Meyer, Anne E; Walker, Gilbert C; Wendt, Dean E; Callow, Maureen E; Callow, James A; Detty, Michael R

2010-08-01

355

Enantiopure Chiral Poly(glycerol methacrylate) Self-Assembled Monolayers Knock Down Protein Adsorption and Cell Adhesion.  

PubMed

Chirality plays a fundamental role not only in biological systems, but also in synthetic materials intended for bio-applications. Self-assembled monolayers (SAMs) are prepared on gold surfaces through a "grafting to" method from racemic or enantiopure chiral poly(glycerol methacrylate)s (PGMA(rac), PGMA(R), and PGMA(S)), having a thiol endgroup. Such SAMs constitute a chemically and structurally well-defined model substrate for studying protein adsorption and cell adhesion as a function of the polymer chirality. Surface plasmon resonance measurements reveal that PGMA SAMs greatly reduce the adsorption of bovine serum albumin (BSA) compared to bare gold surfaces. Interestingly, enantiopure SAMs based on PGMA(R) or PGMA(S) show a significantly larger reduction in BSA adsorption than PGMA(rac)-covered surfaces. Studies with the monocytic cell line THP-1 show a similar relationship between enantiopurity of PGMA SAMs and the extent of cell adhesion. Ellipsometry and Raman spectroscopy measurements indicate that SAMs formed by PGMA(rac) have a higher grafting density compared to SAMs of PGMA(R) and PGMA(S). This seems to be due to the ability of PGMA(rac) to form more intermolecular hydrogen bonds among polymer chains compared to the enantiopure PGMAs. Circular dichroism spectroscopy provide evidence that enantiopure polymers adopt a chiral ordered conformation, most likely helical, in aqueous solutions. It is concluded that a higher water content of SAMs formed by enantiopure PGMA(S) and PGMA(R) SAMs arises from the macromolecular chiral conformation adopted by their enantiopure PGMA chains, and it is the decisive reason for the reduced BSA adsorption and cell adhesion as compared to PGMA(rac) SAMs. PMID:23526806

Li, Zheng; Köwitsch, Alexander; Zhou, Guoying; Groth, Thomas; Fuhrmann, Bodo; Niepel, Marcus; Amado, Elkin; Kressler, Jörg

2013-03-25

356

The tumor suppressor Scrib interacts with the zyxin-related protein LPP, which shuttles between cell adhesion sites and the nucleus  

PubMed Central

Background At sites of cell adhesion, proteins exist that not only perform structural tasks but also have a signaling function. Previously, we found that the Lipoma Preferred Partner (LPP) protein is localized at sites of cell adhesion such as focal adhesions and cell-cell contacts, and shuttles to the nucleus where it has transcriptional activation capacity. LPP is a member of the zyxin family of proteins, which contains five members: ajuba, LIMD1, LPP, TRIP6 and zyxin. LPP has three LIM domains (zinc-finger protein interaction domains) at its carboxy-terminus, which are preceded by a proline-rich pre-LIM region containing a number of protein interaction domains. Results To catch the role of LPP at sites of cell adhesion, we made an effort to identify binding partners of LPP. We found the tumor suppressor protein Scrib, which is a component of cell-cell contacts, as interaction partner of LPP. Human Scrib, which is a functional homologue of Drosophila scribble, is a member of the leucine-rich repeat and PDZ (LAP) family of proteins that is involved in the regulation of cell adhesion, cell shape and polarity. In addition, Scrib displays tumor suppressor activity. The binding between Scrib and LPP is mediated by the PDZ domains of Scrib and the carboxy-terminus of LPP. Both proteins localize in cell-cell contacts. Whereas LPP is also localized in focal adhesions and in the nucleus, Scrib could not be detected at these locations in MDCKII and CV-1 cells. Furthermore, our investigations indicate that Scrib is dispensable for targeting LPP to focal adhesions and to cell-cell contacts, and that LPP is not necessary for localizing Scrib in cell-cell contacts. We show that all four PDZ domains of Scrib are dispensable for localizing this protein in cell-cell contacts. Conclusions Here, we identified an interaction between one of zyxin's family members, LPP, and the tumor suppressor protein Scrib. Both proteins localize in cell-cell contacts. This interaction links Scrib to a communication pathway between cell-cell contacts and the nucleus, and implicates LPP in Scrib-associated functions.

Petit, Marleen MR; Meulemans, Sandra MP; Alen, Philippe; Ayoubi, Torik AY; Jansen, Erik; Van de Ven, Wim JM

2005-01-01

357

Human immunodeficiency virus-1 (HIV-1)-Tat protein promotes migration of acquired immunodeficiency syndrome-related lymphoma cells and enhances their adhesion to endothelial cells.  

PubMed

Human immunodeficiency virus-1 (HIV-1)-Tat, the transactivating gene product of HIV-1, has been shown to interact with different cell types, inducing gene expression, altering their growth and migratory behavior. In this study we examined whether Tat might affect functions of acquired immunodeficiency syndrome (AIDS)-related non-Hodgkin's lymphoma (NHL), relevant to the in vivo dissemination. Our results show that Tat significantly augmented the motility of the two AIDS-related Burkitt's lymphoma cell lines (AS283 and PA682PB) and AIDS-primary effusion lymphoma cell line (HBL-6-AIDS-PEL). Mutations in RGD or basic domain of Tat (KGE-MBP and LxI-MBP, respectively) sharply reduced migration compared with wild type, suggesting that both domains are required for migration. In contrast, a Tat protein mutation outside the active domains (NH(2)-TAT-GST) did not reduce lymphoma cell migration. The treatment of lymphoma cells with Tat did not influence their adhesion to matrix proteins or to human vascular endothelial cells, but endothelial cells treated with Tat became more adhesive to lymphoma cells. Flow cytometric analysis showed that treatment of endothelial cells with Tat induced the cell surface expression of the adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and E-selectin and increased the expression of intercellular adhesion molecule-1 (ICAM-1). Only antibodies against VCAM-1 on endothelial cells or against the VLA-4 integrin expressed on AS283 cells inhibited the increment of adhesion, indicating the relevance of this pathway in the adhesion of lymphoma cells to vascular endothelium. In our work, we show for the first time that Tat can enhance the migration of lymphoma cells and their adhesion to endothelial cells, two processes that may contribute to the malignant behavior of NHL in patients with AIDS. PMID:10477700

Chirivi, R G; Taraboletti, G; Bani, M R; Barra, L; Piccinini, G; Giacca, M; Bussolino, F; Giavazzi, R

1999-09-01

358

Loss of Cadherin-Binding Proteins ?-Catenin and Plakoglobin in the Heart Leads to Gap Junction Remodeling and Arrhythmogenesis  

PubMed Central

Arrhythmic right ventricular cardiomyopathy (ARVC) is a hereditary heart muscle disease that causes sudden cardiac death (SCD) in young people. Almost half of ARVC patients have a mutation in genes encoding cell adhesion proteins of the desmosome, including plakoglobin (JUP). We previously reported that cardiac tissue-specific plakoglobin (PG) knockout (PG CKO) mice have no apparent conduction abnormality and survive longer than expected. Importantly, the PG homolog, ?-catenin (CTNNB1), showed increased association with the gap junction protein connexin43 (Cx43) in PG CKO hearts. To determine whether ?-catenin is required to maintain cardiac conduction in the absence of PG, we generated mice lacking both PG and ?-catenin specifically in the heart (i.e., double knockout [DKO]). The DKO mice exhibited cardiomyopathy, fibrous tissue replacement, and conduction abnormalities resulting in SCD. Loss of the cadherin linker proteins resulted in dissolution of the intercalated disc (ICD) structure. Moreover, Cx43-containing gap junction plaques were reduced at the ICD, consistent with the arrhythmogenicity of the DKO hearts. Finally, ambulatory electrocardiogram monitoring captured the abrupt onset of spontaneous lethal ventricular arrhythmia in the DKO mice. In conclusion, these studies demonstrate that the N-cadherin-binding partners, PG and ?-catenin, are indispensable for maintaining mechanoelectrical coupling in the heart.

Swope, David; Cheng, Lan; Gao, Erhe; Li, Jifen

2012-01-01

359

Adhesion molecule expression in Graves' thyroid glands; potential relevance of granule membrane protein (GMP-140) and intercellular adhesion molecule-1 (ICAM-1) in the homing and antigen presentation processes.  

PubMed Central

To assess the potential role of adhesion molecules in the pathogenesis of Graves' disease, we examined the expression of several of these adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule (VCAM-1) and granule membrane protein-140 (GMP-140), in sections of Graves' thyroid glands and control thyroids, using immunohistochemical techniques. Up-regulated expression of GMP-140 was frequently observed on endothelial cells (EC) of post-capilliary venules in all Graves' thyroids examined, compared with an occasional weak staining on EC control glands. Some capillary EC around thyroid follicles (perifollicular EC) were strongly positive for GMP-140 in the Graves' thyroids in contrast to a negative staining on the same structures in the control glands. In addition, there was a correlation between the reactivity and frequency of GMP-140 expression on EC and the severity of mononuclear cell (MNC) infiltration in the Graves' thyroids. The expression of ICAM-1 was up-regulated on perifollicular EC and EC of small venules in some thyroids of both Graves' and control groups. Conversely, no significant expression was observed on any type of EC for both endothelial-leucocyte adhesion molecule-1 (ELAM-1) and VCAM-1. However, dendritic-like cells, present within lymphocytic infiltrates, were positive for VCAM-1 in most of the Graves' thyroids examined, especially in those with a severe lymphocytic infiltration. Thyrocytes were constantly negative for the expression of all four adhesion molecules investigated. These data suggest that GMP-140, as well as ICAM-1, could play an important role in the initiation of MNC infiltration in Graves' disease. ELAM-1 and VCAM-1 appear not to be relevant for the migration of MNC from the blood vessels into the target gland, although VCAM-1 expression on dendritic-like cells might play an additively tissue-selective role in autoantigen presentation and subsequent elicitation of autoimmune phenomena.

Miyazaki, A; Mirakian, R; Bottazzo, G F

1992-01-01

360

The Yak1 Protein Kinase Lies at the Center of a Regulatory Cascade Affecting Adhesive Growth and Stress Resistance in Saccharomyces cerevisiae  

PubMed Central

In Saccharomyces cerevisiae, adhesive growth on solid surfaces is mediated by the flocculin Flo11 to confer biofilm and filament formation. Expression of FLO11 is governed by a complex regulatory network that includes, e.g., the protein kinase A (PKA) signaling pathway. In addition, numerous regulatory genes, which have not been integrated into regulatory networks, affect adhesive growth, including WHI3 encoding an RNA-binding protein and YAK1 coding for a dual-specificity tyrosine-regulated protein kinase. In this study, we present evidence that Whi3 and Yak1 form part of a signaling pathway that regulates FLO11-mediated surface adhesion and is involved in stress resistance. Our study further suggests that Whi3 controls YAK1 expression at the post-transcriptional level and that Yak1 targets the transcriptional regulators Sok2 and Phd1 to control FLO11. We also discovered that Yak1 regulates acidic stress resistance and adhesion via the transcription factor Haa1. Finally, we provide evidence that the catalytic PKA subunit Tpk1 inhibits Yak1 by targeting specific serine residues to suppress FLO11. In summary, our data suggest that Yak1 is at the center of a regulatory cascade for adhesive growth and stress resistance, which is under dual control of Whi3 and the PKA subunit Tpk1.

Malcher, Mario; Schladebeck, Sarah; Mosch, Hans-Ulrich

2011-01-01

361

Investigation of cell adhesion to silica nanoparticle-decorated surfaces and the associated protein-mediated mechanisms  

NASA Astrophysics Data System (ADS)

Nanostructured materials have shown promise to improve the interface between prosthetic devices and living cells, tissues, and organs through the ability to evoke cell type-specific and size-selective functions from various cell types of in vivo importance. However, the underlying molecular level mechanisms responsible for enhancement of select cell functions on these materials are not fully understood. Silica particles of either 4, 20, or 100 nm diameters were successfully coated onto native-oxide coated silicon substrates in the range of 0 to 100% coverage by particles. The materials formulated and fabricated for the present study provide a controlled and characterized set of substrates needed for investigation of the effects of nanoscale features on the adsorption and conformation of proteins, and subsequent functions of mammalian cells that are critical to the clinical efficacy of biomaterials. The size of nanoscale surface features constituted by silica nanoparticles on native oxide-coated silicon pieces affected the adhesion of rat calvarial osteoblasts and rat skin fibroblasts differently. It was also demonstrated, for the first time, that a threshold density of nanoscale surface features is necessary to elicit size-selective, and cell type-specific, adhesion from osteoblasts or fibroblasts. Adsorption of fibronectin and vitronectin onto native oxide-coated silicon surfaces decorated with either 4, 20, or 100 nm diameter silica particles at either 25, 45, or 80% surface coverage was quantified and examined by scanning electron microscopy. Circular dichroism spectroscopy provided evidence that the secondary structures of fibronectin in the presence of either 4 or 20 nm diameter particles were similar, but fibronectin exhibited decreased beta sheet content and increased unordered structure in the presence of 100 nm particles. The secondary structure of vitronectin in the presence of silica particles exhibited similar levels of structure loss for all particle sizes examined. For the first time, this study offers insight into a molecular mechanism that is linked to nanostructured material surface feature size through quantified changes in protein structure and cell adhesion behavior. These results provide an explanation of the molecular level events occurring on nanostructured material surfaces that contribute to protein-mediated size-selective and cell type-specific responses of various cell types.

Ballard, Jake D.

362

Post-ischemic vascular adhesion protein-1 inhibition provides neuroprotection in a rat temporary middle cerebral artery occlusion model.  

PubMed

We examined the neuroprotective efficacy associated with post-ischemic vascular adhesion protein-1 (VAP-1) blockade in rats subjected to transient (1 h) middle cerebral artery occlusion (MCAo). We compared saline-treated control rats to rats treated with a highly selective VAP-1 inhibitor, LJP-1586 [Z-3-fluoro-2-(4-methoxybenzyl) allylamine hydrochloride]. Initial intraperitoneal LJP-1586 (or saline control) treatments were delayed until 6 h or 12 h reperfusion. At 72-h reperfusion, LJP-1586-treated rats displayed 51% and 33% smaller infarct volumes, relative to their controls, in the 6- and 12-h treatment groups, respectively. However, only in the 6-h treatment group was the infarct volume reduction significant (p < 0.05). On the other hand, we observed significantly improved neurologic functions in both 6- and 12-h treatment groups, versus their matched controls (p < 0.05). Also, the effect of 6-h LJP-1586 treatment on post-ischemic leukocyte trafficking in pial venules overlying the ischemic cortex was evaluated using intravital microscopy. These experiments revealed that: 1) LJP-1586 did not affect intravascular leukocyte (largely neutrophil) adhesion, at least out to 12-h reperfusion; and 2) the onset of neutrophil extravasation, which occurred between 6-8-h reperfusion in control rats, was prevented by LJP-1586-treatment. In conclusion, in rats subjected to transient MCAo, selective VAP-1 pharmacologic blockade provided neuroprotection, with a prolonged therapeutic window of 6-12-h reperfusion. PMID:23050649

Watcharotayangul, Jittiya; Mao, Lizhen; Xu, Haoliang; Vetri, Francesco; Baughman, Verna L; Paisansathan, Chanannait; Pelligrino, Dale A

2012-11-01

363

Structural Analysis of the Synaptic Protein Neuroligin and Its ?-Neurexin Complex: Determinants for Folding and Cell Adhesion  

PubMed Central

SUMMARY The neuroligins are postsynaptic cell adhesion proteins whose associations with presynaptic neurexins participate in synaptogenesis. Mutations in the neuroligin and neurexin genes appear to be associated with autism and mental retardation. The crystal structure of a neuroligin reveals features not found in its catalytically active relatives, such as the fully hydrophobic interface forming the functional neuroligin dimer; the conformations of surface loops surrounding the vestigial active center; the location of determinants that are critical for folding and processing; and the absence of a macromolecular dipole and presence of an electronegative, hydrophilic surface for neurexin binding. The structure of a ?-neurexin-neuroligin complex reveals the precise orientation of the bound neurexin and, despite a limited resolution, provides substantial information on the Ca2+-dependent interactions network involved in trans-synaptic neurexin-neuroligin association. These structures exemplify how an ?/?-hydrolase fold varies in surface topography to confer adhesion properties and provide templates for analyzing abnormal processing or recognition events associated with autism.

Fabrichny, Igor P.; Leone, Philippe; Sulzenbacher, Gerlind; Comoletti, Davide; Miller, Meghan T.; Taylor, Palmer; Bourne, Yves; Marchot, Pascale

2009-01-01

364

Granulocyte transmigration through the endothelium is regulated by the oxidase activity of vascular adhesion protein-1 (VAP-1).  

PubMed

Polymorphonuclear leukocytes (PMNs) migrate from the blood into areas of inflammation by binding to the endothelial cells of blood vessels via adhesion molecules. Vascular adhesion protein-1 (VAP-1) is one of the molecules mediating leukocyte-endothelial cell interactions. It is also an endothelial cell-surface enzyme (amine oxidase) that produces reactive oxygen species during the catalytic reaction. To study the role of the enzymatic activity of VAP-1 in PMN extravasation, we used an enzymatically inactive VAP-1 mutant, specific amine oxidase inhibitors (including a novel small molecule compound), and anti-VAP-1 antibodies in several flow-dependent models. The enzyme inhibitors diminished PMN rolling on and transmigration through human endothelial cells under conditions of laminar shear stress in vitro. Notably, the enzyme inactivating point mutation abolished the capacity of VAP-1 to mediate transmigration. Moreover, the new VAP-1 inhibitor effectively prevented the extravasation of PMNs in an animal model of inflammation. These data show that the oxidase activity of VAP-1 controls PMN exit from the blood during the relatively poorly understood transmigration step. PMID:14726375

Koskinen, Kaisa; Vainio, Petri J; Smith, David J; Pihlavisto, Marjo; Ylä-Herttuala, Seppo; Jalkanen, Sirpa; Salmi, Marko

2004-01-15

365

Recombinant SLayer Proteins of Lactobacillus brevis Mediating Antibody Adhesion to Calf Intestine Alleviated Neonatal Diarrhea Syndrome  

Microsoft Academic Search

A chimeric gene encoding enhanced green fluorescent protein (EGFP) and a S-layer protein from Lactobacillus brevis KCTC3102, and\\/or two copies of the Fc-binding Z-domain, a synthetic analog of the B-domain of protein A, was constructed and expressed in Escherichia coli BL21(DE3). The S-layer fusion proteins produced in a 500-l fermentor were likely to be stable in the range of pH

Yong-Ho Khang; Hee-Young Park; Yoo-Seok Jeong; Jung-Ae Kim; Young-Hwan Kim

2009-01-01

366

'Special K' and a Loss of Cell-To-Cell Adhesion in Proximal Tubule-Derived Epithelial Cells: Modulation of the Adherens Junction Complex by Ketamine  

PubMed Central

Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and ?-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGF?, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention.

Hills, Claire E.; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P.; Squires, Paul E.

2013-01-01

367

The GPS Motif Is a Molecular Switch for Bimodal Activities of Adhesion Class G Protein-Coupled Receptors  

PubMed Central

Summary Adhesion class G protein-coupled receptors (aGPCR) form the second largest group of seven-transmembrane-spanning (7TM) receptors whose molecular layout and function differ from canonical 7TM receptors. Despite their essential roles in immunity, tumorigenesis, and development, the mechanisms of aGPCR activation and signal transduction have remained obscure to date. Here, we use a transgenic assay to define the protein domains required in vivo for the activity of the prototypical aGPCR LAT-1/Latrophilin in Caenorhabditis elegans. We show that the GPCR proteolytic site (GPS) motif, the molecular hallmark feature of the entire aGPCR class, is essential for LAT-1 signaling serving in two different activity modes of the receptor. Surprisingly, neither mode requires cleavage but presence of the GPS, which relays interactions with at least two different partners. Our work thus uncovers the versatile nature of aGPCR activity in molecular detail and places the GPS motif in a central position for diverse protein-protein interactions.

Promel, Simone; Frickenhaus, Marie; Hughes, Samantha; Mestek, Lamia; Staunton, David; Woollard, Alison; Vakonakis, Ioannis; Schoneberg, Torsten; Schnabel, Ralf; Russ, Andreas P.; Langenhan, Tobias

2012-01-01

368

Silk fibroin protein from mulberry and non-mulberry silkworms: cytotoxicity, biocompatibility and kinetics of L929 murine fibroblast adhesion.  

PubMed

Silks fibers and films fabricated from fibroin protein of domesticated mulberry silkworm cocoon have been traditionally utilized as sutures in surgery and recently as biomaterial films respectively. Here, we explore the possibility of application of silk fibroin protein from non-mulberry silkworm cocoon as a potential biomaterial aid. In terms of direct inflammatory potential, fibroin proteins from Antheraea mylitta and Bombyx mori are immunologically inert and invoke minimal immune response. Stimulation of murine peritoneal macrophages and RAW 264.7 murine macrophages by these fibroin proteins both in solution and in the form of films assayed in terms of nitric oxide and TNFalpha production showed comparable stimulation as in collagen. Kinetics of adhesion of L929 murine fibroblasts, for biocompatibility evaluation, monitored every 4 h from seeding and studied over a period of 24 h, reveal A. mylitta fibroin film to be a better substrate in terms of rapid and easier cellularization. Cell viability studies by MTT assay and flow cytometric analyses indicate the ability of fibroin matrices to support cell growth and proliferation comparable to collagen for long-term culture. This matrix may have potential to serve in those injuries where rapid cellularization is essential. PMID:18322779

Acharya, Chitrangada; Ghosh, Sudip K; Kundu, S C

2008-03-06

369

Specific degradation of the mucus adhesion-promoting protein (MapA) of Lactobacillus reuteri to an antimicrobial peptide.  

PubMed

The intestinal flora of mammals contains lactic acid bacteria (LAB) that may provide positive health effects for the host. Such bacteria are referred to as probiotic bacteria. From a pig, we have isolated a Lactobacillus reuteri strain that produces an antimicrobial peptide (AMP). The peptide was purified and characterized, and it was unequivocally shown that the AMP was a well-defined degradation product obtained from the mucus adhesion-promoting protein (MapA); it was therefore termed AP48-MapA. This finding demonstrates how large proteins might inherit unexpected pleiotropic functions by conferring antimicrobial capacities on the producer. The MapA/AP48-MapA system is the first example where a large protein of an intestinal LAB is shown to give rise to such an AMP. It is also of particular interest that the protein that provides this AMP is associated with the binding of the bacterium producing it to the surface/lining of the gut. This finding gives us new perspective on how some probiotic bacteria may successfully compete in this environment and thereby contribute to a healthy microbiota. PMID:20833791

Bøhle, Liv Anette; Brede, Dag Anders; Diep, Dzung B; Holo, Helge; Nes, Ingolf F

2010-09-10

370

ERK1/2 activation in heart is controlled by melusin, focal adhesion kinase and the scaffold protein IQGAP1  

PubMed Central

Extracellular signal-regulated kinase 1/2 (ERK1/2) signalling is a key pathway in cardiomyocyte hypertrophy and survival in response to many different stress stimuli. We have previously characterized melusin as a muscle-specific chaperone protein capable of ERK1/2 signalling activation in the heart. Here, we show that in the heart, melusin forms a supramolecular complex with the proto-oncogene c-Raf, MEK1/2 (also known as MAPKK1/2) and ERK1/2 and that melusin-bound mitogen-activated protein kinases (MAPKs) are activated by pressure overload. Moreover, we demonstrate that both focal adhesion kinase (FAK) and IQ motif-containing GTPase activating protein 1 (IQGAP1), a scaffold protein for the ERK1/2 signalling cascade, are part of the melusin complex and are required for ERK1/2 activation in response to pressure overload. Finally, analysis of isolated neonatal cardiomyocytes indicates that both FAK and IQGAP1 regulate melusin-dependent cardiomyocyte hypertrophy and survival through ERK1/2 activation.

Sbroggio, Mauro; Bertero, Alessandro; Velasco, Silvia; Fusella, Federica; De Blasio, Emanuele; Bahou, Wadie F.; Silengo, Lorenzo; Turco, Emilia; Brancaccio, Mara; Tarone, Guido

2011-01-01

371

Characterization of Spiroplasma citri adhesion related protein SARP1, which contains a domain of a novel family designated sarpin.  

PubMed

Transmission of the plant pathogen Spiroplasma citri by its leafhopper vector, Circulifer tenellus, involves adherence to and invasion of insect host cells. The S. citri adhesion related protein P89 (SARP1) was purified by immunoprecipitation using anti-SARP1 monoclonal antibodies. The protein's N-terminal amino acid sequence was determined and used to design a degenerate oligonucleotide. The labeled oligonucleotide hybridized to a 3.5 kb MboI fragment from S. citri DNA, which was then cloned and sequenced. Additionally, a 1.9 kb RsaI fragment of S. citri DNA, partially overlapping the MboI fragment, was isolated and characterized. Sequence analysis of the two clones revealed four open reading frames. ORF1 (675 bp) encodes the C-terminal part of a Soj-like protein. ORFs 1 and 2 were separated from ORFs 3 and 4 by a putative transcription termination site, indicated by a hairpin structure. ORF3 encodes an amphiphilic 798 amino acid long protein with a cleavable signal peptide and a predicted transmembrane helix near the C-terminus. The mature protein of 85.96 kDa has a calculated pI value of 5.5 and has an N-terminal amino acid sequence consistent with that determined from the purified SARP1. At the N-terminus of this protein is a region consisting of six repeats, each 39-42 amino acids, a motif belonging to a previously unrecognized family of repeats found in a variety of bacterial proteins. The taxonomically spotty presence of this 'sarpin' domain and the relationship of the repeats to each other suggests a convergent evolution in multiple lineages. PMID:11574152

Berg, M; Melcher, U; Fletcher, J

2001-09-01

372

Tyrosine Y189 in the Substrate Domain of the Adhesion Docking Protein NEDD9 Is Conserved with p130Cas Y253 and Regulates NEDD9-Mediated Migration and Focal Adhesion Dynamics  

PubMed Central

The focal adhesion docking protein NEDD9/HEF1/Cas-L regulates cell migration and cancer invasion. NEDD9 is a member of the Cas family of proteins that share conserved overall protein-protein interaction domain structure, including a substrate domain that is characterized by extensive tyrosine (Y) phosphorylation. Previous studies have suggested that phosphorylation of Y253 in the substrate domain of the Cas family protein p130Cas is specifically required for p130Cas function in cell migration. While it is clear that tyrosine phosphorylation of the NEDD9 substrate domain is similarly required for the regulation of cell motility, whether individual NEDD9 tyrosine residues have discrete function in regulating motility has not previously been reported. In the present study we have used a global sequence alignment of Cas family proteins to identify a putative NEDD9 equivalent of p130Cas Y253. We find that NEDD9 Y189 aligns with p130Cas Y253 and that it is conserved among NEDD9 vertebrate orthologues. Expression of NEDD9 in which Y189 is mutated to phenylalanine results in increased rates of cell migration and is correlated with increased disassembly of GFP.NEDD9 focal adhesions. Conversely, mutation to Y189D significantly inhibits cell migration. Our previous data has suggested that NEDD9 stabilizes focal adhesions and the present data therefore suggests that phosphorylation of Y189 NEDD9 is required for this function. These findings indicate that the individual tyrosine residues of the NEDD9 substrate domain may serve discrete functional roles. Given the important role of this protein in promoting cancer invasion, greater understanding of the function of the individual tyrosine residues is important for the future design of approaches to target NEDD9 to arrest cancer cell invasion.

Baquiran, Jaime B.; Bradbury, Peta; O'Neill, Geraldine M.

2013-01-01

373

Dynamic and Static Interactions between p120 Catenin and E-Cadherin Regulate the Stability of Cell-Cell Adhesion  

SciTech Connect

The association of p120 catenin (p120) with the juxtamembrane domain (JMD) of the cadherin cytoplasmic tail is critical for the surface stability of cadherin-catenin cell-cell adhesion complexes. Here, we present the crystal structure of p120 isoform 4A in complex with the JMD core region (JMD{sub core}) of E-cadherin. The p120 armadillo repeat domain contains modular binding pockets that are complementary to electrostatic and hydrophobic properties of the JMD{sub core}. Single-residue mutations within the JMD{sub core}-binding site of p120 abolished its interaction with E- and N-cadherins in vitro and in cultured cells. These mutations of p120 enabled us to clearly differentiate between N-cadherin-dependent and -independent steps of neuronal dendritic spine morphogenesis crucial for synapse development. NMR studies revealed that p120 regulates the stability of cadherin-mediated cell-cell adhesion by associating with the majority of the JMD, including residues implicated in clathrin-mediated endocytosis and Hakai-dependent ubiquitination of E-cadherin, through its discrete dynamic and static binding sites.

Ishiyama, Noboru; Lee, Seung-Hye; Liu, Shuang; Li, Guang-Yao; Smith, Matthew J.; Reichardt, Louis F.; Ikura, Mitsuhiko (OCI); (UCSF)

2010-04-26

374

GP55 inhibits both cell adhesion and growth of neurons, but not non-neuronal cells, via a G-protein-coupled receptor.  

PubMed

There is compelling evidence for the role of inhibitory molecules in guiding neurons to their appropriate targets. Furthermore, continued expression of these molecules in the adult could explain why there is little regeneration of neurons in the central nervous system. We have previously identified a family of glycosyl phosphatidylinositol-linked glycoproteins (GP55) from adult chicken brain that has been shown to inhibit neurite outgrowth from dorsal root ganglion and forebrain neurons. GP55 consists of two or more glycoproteins and belongs to a subgroup of the lg superfamily which contains OBCAM, LAMP, neurotrimin and CEPU-1. We now show that GP55 is anti-adhesive, blocking the adhesion of neurons to normally adhesive substrata in a concentration dependent manner. The anti-adhesive effect can be blocked using antiserum raised against GP55 and pertussis toxin (PTX) but not the beta oligomer alone. In contrast, the adhesion of fibroblasts and Schwann cells to the substrata is not affected by GP55. Indeed, non-neuronal cells spread and grow normally. These results would suggest that both the anti-adhesive effect and the inhibition of outgrowth by GP55 is specific to neurons and is mediated by a PTX sensitive, G-protein-coupled receptor. PMID:9058053

Clarke, G A; Moss, D J

1997-02-01

375

Signaling Transduction Pathway of Angiotensin II in Human Mesangial Cells: Mediation of Focal Adhesion and GTPase Activating Proteins  

Microsoft Academic Search

Human mesangial cells (HMCs) respond to angiotensin II stimulation, which modulates their physiological activities, i.e., contraction and proliferation. It has been revealed that focal adhesion kinase (FAK) and paxillin participate in the angiotensin II-mediated signaling and cytoskeletal rearrangements at focal adhesion. We investigated the influen