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1

Lebectin increases N-cadherin-mediated adhesion through PI3K/AKT pathway.  

PubMed

Cell adhesion molecules, including cadherins and integrins, play an essential role during tumor progression and represent potential targets for the development of new therapeutic agents. We previously showed that lebectin, a C-type lectin protein (CLP) issued from Macrovipera lebectina snake venom, inhibits integrin-mediated migration of IGR39 melanoma cells. Here we assessed whether lebectin modulates cell-cell adhesion. We demonstrated that lebectin promotes N-cadherin/catenin complex reorganization at cell-cell contacts, inducing a strengthening of intercellular adhesion. This reorganization is associated to phosphorylation of beta-catenin on tyrosine 142 residue. Interestingly, lebectin acts on N-cadherin-mediated cell-cell contacts through PI3K/Akt pathway. This effect could contribute to the blockage of tumor cell migration previously observed. PMID:19501458

Sarray, Sameh; Siret, Carole; Lehmann, Maxime; Marrakchi, Naziha; Luis, José; El Ayeb, Mohamed; André, Frédéric

2009-11-28

2

N-cadherin-mediated cell adhesion is regulated by extracellular Zn(2+).  

PubMed

Synapses in the central nervous system (CNS) are highly dynamic structures that undergo reorganisation in response to synaptic activity. Dysfunctional structural synaptic plasticity is associated with impaired brain function and several neurological disorders. As response to synaptic activity, dendritic spines of excitatory synapses were reported to undergo alterations in their molecular structure and morphology leading to increased postsynaptic density size and spine volume. For these structural changes a transient activity-dependent weakening of synaptic adhesion will be necessary. Here, we report that zinc can modulate N-cadherin-mediated adhesion. Quantification of binding activity was performed using laser tweezer technique. Our results show that increased levels of zinc abolished N-cadherin binding without altering the number of N-cadherin molecules expressed at the cell surface. Furthermore, zinc directly interacted with N-cadherin and the regulatory role was found to take place under physiological zinc concentrations within minutes. Given that zinc is released at zincergic synapses in the CNS, our findings may contribute to mechanistic insights in the interplay between zinc signalling, activation of glutamate receptors and downstream pathways, and the coordination of pre- and postsynaptic changes via trans-synaptic cell adhesion complexes, all finally contributing to synaptic plasticity. PMID:25579424

Heiliger, E; Osmanagic, A; Haase, H; Golenhofen, N; Grabrucker, A M; Weth, A; Baumgartner, W

2015-02-11

3

Galectin-3 protein regulates mobility of N-cadherin and GM1 ganglioside at cell-cell junctions of mammary carcinoma cells.  

PubMed

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. PMID:22846995

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

2012-09-21

4

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. PMID:22846995

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

2012-01-01

5

Inhibiting N-cadherin-mediated adhesion affects gap junction communication in isolated rat hearts  

Microsoft Academic Search

Cadherin-mediated adherens junctions is impaired concomitant with a decrease in connexin 43 (Cx43) in diseases or pathological\\u000a processes. We have investigated the acute effects of adherens junction impairment in isolated rat hearts by introducing Ala-His-Ala-Val-Asp-NH2 (AHAVD, a synthetic peptide) as a specific inhibitor of N-cadherin. Effect of AHAVD on N-cadherin mediated adhension was\\u000a analyzed by Cardiomy-ocyte aggregation assay. Laser confocal

Hongjun Zhu; Hegui Wang; Xiwen Zhang; Xiaofeng Hou; Kejiang Cao; Jiangang Zou

2010-01-01

6

Expression of N-cadherin and alpha-catenin in astrocytomas and glioblastomas.  

PubMed Central

We examined levels of mRNA and protein for N-cadherin, the predominant cadherin in neural tissues, and mRNA levels for the cadherin-associated protein, alpha-catenin, in a series of gliomas and in glioblastoma cell lines. mRNA levels for N-cadherin and alpha-catenin were significantly higher in glioblastomas than in low-grade astrocytomas or normal brain, while the levels of intact N-cadherin protein were similar in glioblastomas, low-grade astrocytomas and brain. In addition, there was no consistent relationship between invasiveness and expression of N-cadherin and alpha-catenin in highly invasive vs minimally invasive tumours within the same histopathological grade. To assess further the relationship between cadherin expression and neural tumour invasion, we measured N-cadherin expression, calcium-dependent cell adhesion and motility of several glioblastoma cell lines. While all N-cadherin-expressing lines were adhesive, no correlation was seen between the level of N-cadherin expression and cell motility. Together, these findings imply that, in contrast to the role played by E-cadherin in carcinomas, N-cadherin does not restrict the invasion of glioblastomas. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7669572

Shinoura, N.; Paradies, N. E.; Warnick, R. E.; Chen, H.; Larson, J. J.; Tew, J. J.; Simon, M.; Lynch, R. A.; Kanai, Y.; Hirohashi, S.

1995-01-01

7

Striatal neurons expressing full-length mutant huntingtin exhibit decreased N-cadherin and altered neuritogenesis  

PubMed Central

The expanded CAG repeat that causes striatal cell vulnerability in Huntington's disease (HD) encodes a polyglutamine tract in full-length huntingtin that is correlated with cellular [ATP] and [ATP/ADP]. Since striatal neurons are vulnerable to energy deficit, we have investigated, in Hdh CAG knock-in mice and striatal cells, the hypothesis that decreased energetics may affect neuronal (N)-cadherin, a candidate energy-sensitive adhesion protein that may contribute to HD striatal cell sensitivity. In vivo, N-cadherin was sensitive to ischemia and to the effects of full-length mutant huntingtin, progressively decreasing in HdhQ111 striatum with age. In cultured striatal cells, N-cadherin was decreased by ATP depletion and STHdhQ111 striatal cells exhibited dramatically decreased N-cadherin, due to decreased Cdh2 mRNA and enhanced N-cadherin turnover, which was partially normalized by adenine supplementation to increase [ATP] and [ATP/ADP]. Consistent with decreased N-cadherin function, STHdhQ111 striatal cells displayed profound deficits in calcium-dependent N-cadherin-mediated cell clustering and cell–substratum adhesion, and primary HdhQ111 striatal neuronal cells exhibited decreased N-cadherin and an abundance of immature neurites, featuring diffuse, rather than clustered, staining for N-cadherin and synaptic vesicle markers, which was partially rescued by adenine treatment. Thus, mutant full-length huntingtin, via energetic deficit, contributes to decreased N-cadherin levels in striatal neurons, with detrimental effects on neurite maturation, strongly suggesting that N-cadherin-mediated signaling merits investigation early in the HD pathogenic disease process. PMID:21447599

Reis, Surya A.; Thompson, Morgan N.; Lee, Jong-Min; Fossale, Elisa; Kim, Hyung-Hwan; Liao, James K.; Moskowitz, Michael A.; Shaw, Stanley Y.; Dong, Linda; Haggarty, Stephen J.; MacDonald, Marcy E.; Seong, Ihn Sik

2011-01-01

8

E-Cadherin Can Replace N-Cadherin during Secretory-Stage Enamel Development  

PubMed Central

Background N-cadherin is a cell-cell adhesion molecule and deletion of N-cadherin in mice is embryonic lethal. During the secretory stage of enamel development, E-cadherin is down-regulated and N-cadherin is specifically up-regulated in ameloblasts when groups of ameloblasts slide by one another to form the rodent decussating enamel rod pattern. Since N-cadherin promotes cell migration, we asked if N-cadherin is essential for ameloblast cell movement during enamel development. Methodology/Principal Findings The enamel organ, including its ameloblasts, is an epithelial tissue and for this study a mouse strain with N-cadherin ablated from epithelium was generated. Enamel from wild-type (WT) and N-cadherin conditional knockout (cKO) mice was analyzed. ?CT and scanning electron microscopy showed that thickness, surface structure, and prism pattern of the cKO enamel looked identical to WT. No significant difference in hardness was observed between WT and cKO enamel. Interestingly, immunohistochemistry revealed the WT and N-cadherin cKO secretory stage ameloblasts expressed approximately equal amounts of total cadherins. Strikingly, E-cadherin was not normally down-regulated during the secretory stage in the cKO mice suggesting that E-cadherin can compensate for the loss of N-cadherin. Previously it was demonstrated that bone morphogenetic protein-2 (BMP2) induces E- and N-cadherin expression in human calvaria osteoblasts and we show that the N-cadherin cKO enamel organ expressed significantly more BMP2 and significantly less of the BMP antagonist Noggin than did WT enamel organ. Conclusions/Significance The E- to N-cadherin switch at the secretory stage is not essential for enamel development or for forming the decussating enamel rod pattern. E-cadherin can substitute for N-cadherin during these developmental processes. Bmp2 expression may compensate for the loss of N-cadherin by inducing or maintaining E-cadherin expression when E-cadherin is normally down-regulated. Notably, this is the first demonstration of a natural endogenous increase in E-cadherin expression due to N-cadherin ablation in a healthy developing tissue. PMID:25014356

Guan, Xiaomu; Bidlack, Felicitas B.; Stokes, Nicole; Bartlett, John D.

2014-01-01

9

N-cadherin expression in malignant germ cell tumours of the testis  

PubMed Central

Background Testicular germ cell tumours (TGCTs) are the most common malignancy in young men aged 18–35 years. They are clinically and histologically subdivided into seminomas and non-seminomas. Cadherins are calcium-dependent transmembrane proteins of the group of adhesion proteins. They play a role in the stabilization of cell-cell contacts, the embryonic morphogenesis, in the maintenance of cell polarity and signal transduction. N-cadherin (CDH2), the neuronal cadherin, stimulates cell-cell contacts during migration and invasion of cells and is able to suppress tumour cell growth. Methods Tumour tissues were acquired from 113 male patients and investigated by immunohistochemistry, as were the three TGCT cell lines NCCIT, NTERA-2 and Tcam2. A monoclonal antibody against N-cadherin was used. Results Tumour-free testis and intratubular germ cell neoplasias (unclassified) (IGCNU) strongly expressed N-cadherin within the cytoplasm. In all seminomas investigated, N-cadherin expression displayed a membrane-bound location. In addition, the teratomas and yolk sac tumours investigated also differentially expressed N-cadherin. In contrast, no N-cadherin could be detected in any of the embryonal carcinomas and chorionic carcinomas examined. This expression pattern was also seen in the investigated mixed tumours consisting of seminomas, teratomas, and embryonal carcinoma. Conclusions N-cadherin expression can be used to differentiate embryonal carcinomas and chorionic carcinomas from other histological subtypes of TGCT. PMID:23066729

2012-01-01

10

ICAM-2 regulates vascular permeability and N-cadherin localization through ezrin-radixin-moesin (ERM) proteins and Rac-1 signalling  

PubMed Central

Background Endothelial junctions control functions such as permeability, angiogenesis and contact inhibition. VE-Cadherin (VECad) is essential for the maintenance of intercellular contacts. In confluent endothelial monolayers, N-Cadherin (NCad) is mostly expressed on the apical and basal membrane, but in the absence of VECad it localizes at junctions. Both cadherins are required for vascular development. The intercellular adhesion molecule (ICAM)-2, also localized at endothelial junctions, is involved in leukocyte recruitment and angiogenesis. Results In human umbilical vein endothelial cells (HUVEC), both VECad and NCad were found at nascent cell contacts of sub-confluent monolayers, but only VECad localized at the mature junctions of confluent monolayers. Inhibition of ICAM-2 expression by siRNA caused the appearance of small gaps at the junctions and a decrease in NCad junctional staining in sub-confluent monolayers. Endothelioma lines derived from WT or ICAM-2-deficient mice (IC2neg) lacked VECad and failed to form junctions, with loss of contact inhibition. Re-expression of full-length ICAM-2 (IC2 FL) in IC2neg cells restored contact inhibition through recruitment of NCad at the junctions. Mutant ICAM-2 lacking the binding site for ERM proteins (IC2 ?ERM) or the cytoplasmic tail (IC2 ?TAIL) failed to restore junctions. ICAM-2-dependent Rac-1 activation was also decreased in these mutant cell lines. Barrier function, measured in vitro via transendothelial electrical resistance, was decreased in IC2neg cells, both in resting conditions and after thrombin stimulation. This was dependent on ICAM-2 signalling to the small GTPase Rac-1, since transendothelial electrical resistance of IC2neg cells was restored by constitutively active Rac-1. In vivo, thrombin-induced extravasation of FITC-labeled albumin measured by intravital fluorescence microscopy in the mouse cremaster muscle showed that permeability was increased in ICAM-2-deficient mice compared to controls. Conclusions These results indicate that ICAM-2 regulates endothelial barrier function and permeability through a pathway involving N-Cadherin, ERMs and Rac-1. PMID:24593809

2014-01-01

11

Regulation of N-Cadherin Dynamics at Neuronal Contacts by Ligand Binding and Cytoskeletal Coupling  

PubMed Central

N-cadherin plays a key role in axonal outgrowth and synaptogenesis, but how neurons initiate and remodel N-cadherin-based adhesions remains unclear. We addressed this issue with a semiartificial system consisting of N-cadherin coated microspheres adhering to cultured neurons transfected for N-cadherin-GFP. Using optical tweezers, we show that growth cones are particularly reactive to N-cadherin coated microspheres, which they capture in a few seconds and drag rearward. Such strong coupling requires an intact connection between N-cadherin receptors and catenins. As they move to the basis of growth cones, microspheres slow down while gradually accumulating N-cadherin-GFP, demonstrating a clear delay between bead coupling to the actin flow and receptor recruitment. Using FRAP and photoactivation, N-cadherin receptors at bead-to-cell contacts were found to continuously recycle, consistently with a model of ligand-receptor reaction not limited by membrane diffusion. The use of N-cadherin-GFP receptors truncated or mutated in specific cytoplasmic regions show that N-cadherin turnover is exquisitely regulated by catenin partners. Turnover rates are considerably lower than those obtained previously in single molecule studies, demonstrating an active regulation of cadherin bond kinetics in intact cells. Finally, spontaneous neuronal contacts enriched in N-cadherin exhibited similar turnover rates, suggesting that such dynamics of N-cadherin may represent an intrinsic mechanism underlying the plasticity of neuronal adhesions. PMID:16319177

Thoumine, Olivier; Lambert, Mireille; Mège, René-Marc; Choquet, Daniel

2006-01-01

12

Single-Cell Adhesion Tests against Functionalized Microspheres Arrayed on AFM Cantilevers Confirm Heterophilic E-and N-Cadherin Binding  

E-print Network

Single-Cell Adhesion Tests against Functionalized Microspheres Arrayed on AFM Cantilevers Confirm: vheinrich@ucdavis.edu Cadherins are calcium-dependent adhesion proteins that mediate vital physiological of processes like cadherin-medi- ated cell-cell adhesion. However, as long as each selected cell can only

Heinrich, Volkmar

13

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. PMID:23227006

Flannery, Richard J.; Brusés, Juan L.

2012-01-01

14

N-CADHERIN PRODOMAIN CLEAVAGE REGULATES SYNAPSE FORMATION IN VIVO  

PubMed Central

Cadherins are initially synthesized bearing a prodomain that is thought to limit adhesion during early stages of biosynthesis. Functional cadherins lack this prodomain, raising the intriguing possibility that cells may utilize prodomain cleavage as a means to temporally or spatially regulate adhesion after delivery of cadherin to the cell surface. In support of this idea, immunostaining for the prodomain of zebrafish N-cadherin revealed enriched labeling at neuronal surfaces at the soma and along axonal processes. To determine whether post-translational cleavage of the prodomain affects synapse formation, we imaged Rohon-Beard cells in zebrafish embryos expressing GFP-tagged wild-type N-cadherin (NCAD-GFP) or a GFP-tagged N-cadherin mutant expressing an uncleavable prodomain (PRON-GFP) rendering it non-adhesive. NCAD-GFP accumulated at synaptic microdomains in a developmentally regulated manner, and its overexpression transiently accelerated synapse formation. PRON-GFP was much more diffusely distributed along the axon and its overexpression delayed synapse formation. Our results support the notion that N-cadherin serves to stabilize pre- to postsynaptic contacts early in synapse development and suggests that regulated cleavage of the N-cadherin prodomain may be a mechanism by which the kinetics of synaptogenesis are regulated. PMID:19365814

Latefi, Nazlie S.; Pedraza, Liliana; Schohl, Anne; Li, Ziwei; Ruthazer, Edward S.

2009-01-01

15

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. PMID:23626818

Brusés, Juan L.

2013-01-01

16

Presence of N-cadherin transcripts in mature spermatozoa  

Microsoft Academic Search

homotypically with their target, are morphoregulatory and function eptopically to affect tissue form and function. Cadherins and cadherin-associated molecules have been identified in testes and germinal cells, as well as ejaculated spermatozoa. Moreover, cadherins are also present in oocytes and may suggest a cadherin- mediated adhesion in sperm-oocyte interaction. We have detected antigenic epitopes recognized by N- cadherin monoclonal antibodies

Leslie O. Goodwin; David S. Karabinus; Robert G. Pergolizzi

2000-01-01

17

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

18

N-Cadherin Promotes Recruitment and Migration of Neural Progenitor Cells from the SVZ Neural Stem Cell Niche into Demyelinated Lesions  

PubMed Central

Discrete cellular microenvironments regulate stem cell pools and their development, as well as function in maintaining tissue homeostasis. Although the signaling elements modulating neural progenitor cells (NPCs) of the adult subventricular zone (SVZ) niche are fairly well understood, the pathways activated following injury and the resulting outcomes, are less clear. In the present study, we used mouse models of demyelination and proteomics analysis to identify molecular cues present in the adult SVZ niche during injury, and analyzed their role on NPCs in the context of promoting myelin repair. Proteomic analysis of SVZ tissue from mice with experimental demyelination identified several proteins that are known to play roles in NPC proliferation, adhesion, and migration. Among the proteins found to be upregulated were members of the N-cadherin signaling pathway. During the onset of demyelination in the subcortical white matter (SCWM), activation of epidermal growth factor receptor (EGFR) signaling in SVZ NPCs stimulates the interaction between N-cadherin and ADAM10. Upon cleavage and activation of N-cadherin signaling by ADAM10, NPCs undergo cytoskeletal rearrangement and polarization, leading to enhanced migration out of the SVZ into demyelinated lesions of the SCWM. Genetically disrupting either EGFR signaling or ADAM10 inhibits this pathway, preventing N-cadherin regulated NPC polarization and migration. Additionally, in vivo experiments using N-cadherin gain- and loss-of-function approaches demonstrated that N-cadherin enhances the recruitment of SVZ NPCs into demyelinated lesions. Our data revealed that EGFR-dependent N-cadherin signaling physically initiated by ADAM10 cleavage is the response of the SVZ niche to promote repair of the injured brain. PMID:25031401

Klingener, Michael; Chavali, Manideep; Singh, Jagdeep; McMillan, Nadia; Coomes, Alexandra; Dempsey, Peter J.; Chen, Emily I.

2014-01-01

19

Effects of N-Cadherin Disruption on Spine Morphological Dynamics  

PubMed Central

Structural changes at synapses are thought to be a key mechanism for the encoding of memories in the brain. Recent studies have shown that changes in the dynamic behavior of dendritic spines accompany bidirectional changes in synaptic plasticity, and that the disruption of structural constraints at synapses may play a mechanistic role in spine plasticity. While the prolonged disruption of N-cadherin, a key synaptic adhesion molecule, has been shown to alter spine morphology, little is known about the short-term regulation of spine morphological dynamics by N-cadherin. With time-lapse, confocal imaging in cultured hippocampal neurons, we examined the progression of structural changes in spines following an acute treatment with AHAVD, a peptide known to interfere with the function of N-cadherin. We characterized fast and slow timescale spine dynamics (minutes and hours, respectively) in the same population of spines. We show that N-cadherin disruption leads to enhanced spine motility and reduced length, followed by spine loss. The structural effects are accompanied by a loss of functional connectivity. Further, we demonstrate that early structural changes induced by AHAVD treatment, namely enhanced motility and reduced length, are indicators for later spine fate, i.e., spines with the former changes are more likely to be subsequently lost. Our results thus reveal the short-term regulation of synaptic structure by N-cadherin and suggest that some forms of morphological dynamics may be potential readouts for subsequent, stimulus-induced rewiring in neuronal networks. PMID:18946519

Mysore, Shreesh P.; Tai, Chin-Yin; Schuman, Erin M.

2007-01-01

20

N-Cadherin Sustains Motility and Polarity of Future Cortical Interneurons during Tangential Migration  

PubMed Central

In the developing brain, cortical GABAergic interneurons migrate long distances from the medial ganglionic eminence (MGE) in which they are generated, to the cortex in which they settle. MGE cells express the cell adhesion molecule N-cadherin, a homophilic cell–cell adhesion molecule that regulates numerous steps of brain development, from neuroepithelium morphogenesis to synapse formation. N-cadherin is also expressed in embryonic territories crossed by MGE cells during their migration. In this study, we demonstrate that N-cadherin is a key player in the long-distance migration of future cortical interneurons. Using N-cadherin-coated substrate, we show that N-cadherin-dependent adhesion promotes the migration of mouse MGE cells in vitro. Conversely, mouse MGE cells electroporated with a construct interfering with cadherin function show reduced cell motility, leading process instability, and impaired polarization associated with abnormal myosin IIB dynamics. In vivo, the capability of electroporated MGE cells to invade the developing cortical plate is altered. Using genetic ablation of N-cadherin in mouse embryos, we show that N-cadherin-depleted MGEs are severely disorganized. MGE cells hardly exit the disorganized proliferative area. N-cadherin ablation at the postmitotic stage, which does not affect MGE morphogenesis, alters MGE cell motility and directionality. The tangential migration to the cortex of N-cadherin ablated MGE cells is delayed, and their radial migration within the cortical plate is perturbed. Altogether, these results identify N-cadherin as a pivotal adhesion substrate that activates cell motility in future cortical interneurons and maintains cell polarity over their long-distance migration to the developing cortex. PMID:24227724

Luccardini, Camilla; Hennekinne, Laetitia; Viou, Lucie; Yanagida, Mitsutoshi; Murakami, Fujio; Kessaris, Nicoletta; Ma, Xufei; Adelstein, Robert S.; Mège, René-Marc

2013-01-01

21

Inhibition of N-cadherin and beta-catenin function reduces axon-induced Schwann cell proliferation.  

PubMed

N-cadherin and beta-catenin are involved in cell adhesion and cell cycle in tumor cells and neural crest. Both are expressed at key stages of Schwann cell (SC) development, but little is known about their function in the SC lineage. We studied the role of these molecules in adult rat derived SC-embryonic dorsal root ganglion cocultures by using low-Ca(2+) conditions and specific blocking antibodies to interfere with N-cadherin function and by using small interfering RNA (siRNA) to decrease beta-catenin expression in both SC-neuron cocultures and adult rat-derived SC monocultures. N-cadherin blocking conditions decreased SC-axon association and reduced axon-induced SC proliferation. In SC monocultures, beta-catenin reduction diminished the proliferative response of SCs to the mitogen beta1-heregulin, and, in SC-DRG cocultures, beta-catenin reduction inhibited axon-contact-dependent SC proliferation. Stimulation of SC cultures with beta1-heregulin increased total beta-catenin protein amount, phosphorylation of GSK-3beta and beta-catenin presence in nuclear extracts. In conclusion, our findings suggest a previously unrecognized contribution of beta-catenin and N-cadherin to axon-induced SC proliferation. PMID:17941050

Gess, Burkhard; Halfter, Hartmut; Kleffner, Ilka; Monje, Paula; Athauda, Gagani; Wood, Patrick M; Young, Peter; Wanner, Ina B

2008-03-01

22

Correlation of N-cadherin expression in high grade gliomas with tissue invasion.  

PubMed

Cadherins are Ca2+-dependent cell adhesion molecules that play an important role in tissue construction and morphogenesis in multicellular organisms. Over the last few years, reports have emerged in the literature describing the involvement of cadherins in tumor invasion and metastasis. Cadherins typically demonstrate up and down-regulation according to the biological needs of the tissue. Additionally, up-regulation of N-cadherin is thought to be important for tumor formation in early stages of tumor development. We studied N-cadherin in surgical specimens of patients with primary glioblastoma by microarray analysis and found that N-cadherin mRNA expression is up-regulated compared to normal brain. To study the effects of N-cadherin expression on invasion and metastasis in vitro and in vivo, we overexpressed N-cadherin in the rat C6 glioma cell line which normally has low levels of N-cadherin. We found that up-regulation of N-cadherin resulted in a slight decreased adhesion to type IV collagen, fibronectin, and laminin, but statistically significant decreased adhesion to type I collagen. Furthermore, increased expression of N-cadherin correlated with a dramatic decrease in invasive behavior in extracellular matrix invasion assays. We then proceeded to study these cell lines in vivo in a rat intracranial glioma model, and found that N-cadherin expression inversely correlated with invasion into surrounding tissues, irregular margins, and extracranial invasion. In summary, these data collectively demonstrate that N-cadherin levels are important in the malignant behavior of gliomas, and may serve as a prognostic indicator for patients with high-grade gliomas. PMID:15527101

Asano, Kenichiro; Duntsch, Christopher D; Zhou, Qihong; Weimar, James D; Bordelon, Dwight; Robertson, Jon H; Pourmotabbed, Tayebeh

2004-10-01

23

Quantitative Immunohistochemistry of Desmosomal Proteins (Plakoglobin, Desmoplakin and Plakophilin), Connexin-43, and N-cadherin in Arrhythmogenic Cardiomyopathy: An Autopsy Study  

PubMed Central

Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder related to mutations in desmosomal proteins. The current study tests the hypothesis that immunohistochemical staining for desmosomal proteins is of diagnostic utility by studying autopsy-confirmed cases of ARVC. Methods and Results: We studied 23 hearts from patients dying suddenly with ARVC. Control subject tissues were 21 hearts from people dying from non-cardiac causes (n=15), dilated cardiomyopathy (n=3) and coronary artery disease (n=3). Areas free of fibrofatty change or scarring were assessed on 50 sections from ARVC (24 left ventricle, 26 right ventricle) and 28 sections from controls. Immunohistochemical stains against plakoglobin, plakophilin, desmoplakin, connexin-43, and N-cadherin were applied and area expression analyzed by computerized morphometry. Desmin was stained as a control for fixation and similarly analyzed. The mean area of desmin expression was similar in controls and ARVC (86% vs. 85%, p=0.6). Plakoglobin expression was 4.9% ± 0.3% in controls, vs. 4.6% ± 0.3% in ARVC (p=0.3). Plakophilin staining was 4.8% ± 0.3% in controls vs. 4.4% ± 03% in ARVC (p=0.3). Desmoplakin staining was 3.4% in controls vs. 3.2 ± 0.2% in ARVC (p=0.6). There were no significant differences when staining was compared between right and left ventricles (all p > 0.1). For non-desmosomal proteins, the mean area of connexin-43 staining showed no significant difference by presence of disease. Conclusions: The small and insignificant decrease in junction protein expression in ARVC suggests that immunohistochemistry is not a useful tool for the diagnosis. PMID:23802019

Tavora, Fabio; Zhang, Mingchang; Cresswell, Nathaniel; Li, Ling; Fowler, David; Franco, Marcello; Burke, Allen

2013-01-01

24

Dlg5 regulates dendritic spine formation and synaptogenesis by controlling subcellular N-cadherin localization.  

PubMed

Most excitatory synapses in the mammalian brain are formed on dendritic spines, and spine density has a profound impact on synaptic transmission, integration, and plasticity. Membrane-associated guanylate kinase (MAGUK) proteins are intracellular scaffolding proteins with well established roles in synapse function. However, whether MAGUK proteins are required for the formation of dendritic spines in vivo is unclear. We isolated a novel disc large-5 (Dlg5) allele in mice, Dlg5(LP), which harbors a missense mutation in the DLG5 SH3 domain, greatly attenuating its ability to interact with the DLG5 GUK domain. We show here that DLG5 is a MAGUK protein that regulates spine formation, synaptogenesis, and synaptic transmission in cortical neurons. DLG5 regulates synaptogenesis by enhancing the cell surface localization of N-cadherin, revealing a key molecular mechanism for regulating the subcellular localization of this cell adhesion molecule during synaptogenesis. PMID:25232112

Wang, Shih-Hsiu J; Celic, Ivana; Choi, Se-Young; Riccomagno, Martin; Wang, Qiang; Sun, Lu O; Mitchell, Sarah P; Vasioukhin, Valera; Huganir, Richard L; Kolodkin, Alex L

2014-09-17

25

Extracellular interactions between GluR2 and N-cadherin in spine regulation.  

PubMed

Via its extracellular N-terminal domain (NTD), the AMPA receptor subunit GluR2 promotes the formation and growth of dendritic spines in cultured hippocampal neurons. Here we show that the first N-terminal 92 amino acids of the extracellular domain are necessary and sufficient for GluR2's spine-promoting activity. Moreover, overexpression of this extracellular domain increases the frequency of miniature excitatory postsynaptic currents (mEPSCs). Biochemically, the NTD of GluR2 can interact directly with the cell adhesion molecule N-cadherin, in cis or in trans. N-cadherin-coated beads recruit GluR2 on the surface of hippocampal neurons, and N-cadherin immobilization decreases GluR2 lateral diffusion on the neuronal surface. RNAi knockdown of N-cadherin prevents the enhancing effect of GluR2 on spine morphogenesis and mEPSC frequency. Our data indicate that in hippocampal neurons N-cadherin and GluR2 form a synaptic complex that stimulates presynaptic development and function as well as promoting dendritic spine formation. PMID:17481398

Saglietti, Laura; Dequidt, Caroline; Kamieniarz, Kinga; Rousset, Marie-Claude; Valnegri, Pamela; Thoumine, Olivier; Beretta, Francesca; Fagni, Laurent; Choquet, Daniel; Sala, Carlo; Sheng, Morgan; Passafaro, Maria

2007-05-01

26

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. PMID:19162191

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

2010-01-01

27

N-cadherin Determines Individual Variations in the Therapeutic Efficacy of Human Umbilical Cord Blood-derived Mesenchymal Stem Cells in a Rat Model of Myocardial Infarction  

PubMed Central

In this study, we established and characterized human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) from four different donors. However, the hUCB-MSCs showed remarkable variations in their therapeutic efficacy for repairing rat infarcted myocardium (including the process of angiogenesis) 8 weeks after transplantation. In addition, we observed that the level of vascular endothelial growth factor (VEGF) is correlated with the therapeutic efficacy of the four hUCB-MSCs. Next, to investigate the practical application of hUCB-MSCs, we searched for surface signature molecules that could serve as indicators of therapeutic efficacy. The gene for N-cadherin was the only cell surface gene that was highly expressed in the most effective hUCB-MSCs, both at the transcriptional and translational levels. We observed downregulation and upregulation of VEGF in response to N-cadherin blocking and N-cadherin overexpression, respectively. Activation of extracellular signal-regulated kinase (ERK), but not protein kinase B, was increased when N-cadherin expression was increased, whereas disruption of N-cadherin-mediated cell–cell contact induced suppression of ERK activation and led to VEGF downregulation. Moreover, by investigating hUCB-MSCs overexpressing N-cadherin or N-cadherin knockdown hUCB-MSCs, we confirmed the in vivo function of N-cadherin. In addition, we observed that DiI-labeled hUCB-MSCs express N-cadherin in the peri-infarct area and interact with cardiomyocytes. PMID:22068423

Lee, Eun Ju; Choi, Eue-Keun; Kang, Soo Kyoung; Kim, Gi-Hwan; Park, Ju Young; Kang, Hyun-Jae; Lee, Sae-Won; Kim, Keum-Hyun; Kwon, Jin Sook; Lee, Ki Hong; Ahn, Youngkeun; Lee, Ho-Jae; Cho, Hyun-Jai; Choi, Soo Jin; Oh, Won Il; Park, Young-Bae; Kim, Hyo-Soo

2012-01-01

28

N-cadherin prevents the premature differentiation of anterior heart field progenitors in the pharyngeal mesodermal microenvironment  

PubMed Central

The cardiac progenitor cells (CPCs) in the anterior heart field (AHF) are located in the pharyngeal mesoderm (PM), where they expand, migrate and eventually differentiate into major cell types found in the heart, including cardiomyocytes. The mechanisms by which these progenitors are able to expand within the PM microenvironment without premature differentiation remain largely unknown. Through in silico data mining, genetic loss-of-function studies, and in vivo genetic rescue studies, we identified N-cadherin and interaction with canonical Wnt signals as a critical component of the microenvironment that facilitates the expansion of AHF-CPCs in the PM. CPCs in N-cadherin mutant embryos were observed to be less proliferative and undergo premature differentiation in the PM. Notably, the phenotype of N-cadherin deficiency could be partially rescued by activating Wnt signaling, suggesting a delicate functional interaction between the adhesion role of N-cadherin and Wnt signaling in the early PM microenvironment. This study suggests a new mechanism for the early renewal of AHF progenitors where N-cadherin provides additional adhesion for progenitor cells in the PM, thereby allowing Wnt paracrine signals to expand the cells without premature differentiation. PMID:25367124

Soh, Boon-Seng; Buac, Kristina; Xu, Huansheng; Li, Edward; Ng, Shi-Yan; Wu, Hao; Chmielowiec, Jolanta; Jiang, Xin; Bu, Lei; Li, Ronald A; Cowan, Chad; Chien, Kenneth R

2014-01-01

29

Correlation of N-cadherin expression in high grade gliomas with tissue invasion  

Microsoft Academic Search

Cadherins are Ca2+-dependent cell adhesion molecules that play an important role in tissue construction and morphogenesis in multicellular organisms. Over the last few years, reports have emerged in the literature describing the involvement of cadherins in tumor invasion and metastasis. Cadherins typically demonstrate up and down-regulation according to the biological needs of the tissue. Additionally, up-regulation of N-cadherin is thought

Kenichiro Asano; Christopher D. Duntsch; Qihong Zhou; James D. Weimar; Dwight Bordelon; Jon H. Robertson; Tayebeh Pourmotabbed

2004-01-01

30

Persistence of coordinated LTP and dendritic spine enlargement at mature hippocampal CA1 synapses requires N-cadherin  

PubMed Central

Persistent changes in spine shape are coupled to long-lasting synaptic plasticity in hippocampus. The molecules that coordinate such persistent structural and functional plasticity are unknown. Here, we generated mice in which the cell adhesion molecule N-cadherin was conditionally ablated from postnatal, excitatory synapses in hippocampus. We applied to adult mice of either sex a combination of whole-cell recording, 2-photon microscopy, and spine morphometric analysis to show that postnatal ablation of N-cadherin has profound effects on the stability of coordinated spine enlargement and long-term potentiation (LTP) at mature CA1 synapses, with no effects on baseline spine density or morphology, baseline properties of synaptic neurotransmission, or long-term depression (LTD). Thus, N-cadherin couples persistent spine structural modifications with long-lasting synaptic functional modifications associated selectively with LTP, revealing unexpectedly distinct roles at mature synapses in comparison with earlier, broader functions in synapse and spine development. PMID:20668183

Bozdagi, Ozlem; Wang, Xiao-bin; Nikitczuk, Jessica S.; Anderson, Tonya R.; Bloss, Erik B.; Radice, Glenn L.; Zhou, Qiang; Benson, Deanna L.; Huntley, George W.

2010-01-01

31

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. PMID:23097623

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

2012-01-01

32

Adhesives from modified soy protein  

DOEpatents

The, present invention provides useful adhesive compositions having similar adhesive properties to conventional UF and PPF resins. The compositions generally include a protein portion and modifying ingredient portion selected from the group consisting of carboxyl-containing compounds, aldehyde-containing compounds, epoxy group-containing compounds, and mixtures thereof. The composition is preferably prepared at a pH level at or near the isoelectric point of the protein. In other preferred forms, the adhesive composition includes a protein portion and a carboxyl-containing group portion.

Sun, Susan (Manhattan, KS); Wang, Donghai (Manhattan, KS); Zhong, Zhikai (Manhattan, KS); Yang, Guang (Shanghai, CN)

2008-08-26

33

Surface Expression of Precursor N-cadherin Promotes Tumor Cell Invasion12  

PubMed Central

The expression of N-cadherin (NCAD) has been shown to correlate with increased tumor cell motility and metastasis. However, NCAD-mediated adhesion is a robust phenomenon and therefore seems to be inconsistent with the “release” from intercellular adhesion required for invasion. We show that in the most invasive melanoma and brain tumor cells, altered posttranslational processing results in abundant nonadhesive precursor N-cadherin (proNCAD) at the cell surface, although total NCAD levels remain constant. We demonstrate that aberrantly processed proNCAD promotes cell migration and invasion in vitro. Furthermore, in human tumor specimens, we find high levels of proNCAD as well, supporting an overall conclusion that proNCAD and mature NCAD coexist on these tumor cell surfaces and that it is the ratio between these functionally antagonistic moieties that directly correlates with invasion potential. Our work provides insight into what may be a widespread mechanism for invasion and metastasis and challenges the current dogma of the functional roles played by classic cadherins in tumor progression. PMID:21170270

Maret, Deborah; Gruzglin, Eugenia; Sadr, Mohamad Seyed; Siu, Vincent; Shan, Weisong; Koch, Alexander W; Seidah, Nabil G; Del Maestro, Rolando F; Colman, David R

2010-01-01

34

N-Cadherin Prodomain Cleavage Regulates Synapse Formation In Vivo  

E-print Network

in a developmentally regulated manner, and its overexpression transiently accelerated synapse for- mation. PRON in the formation and maturation of the synapse (Sperry, 1963; Vaughn, 1989; Fannon and Colman, 1996; Benson molecule N-cadherin is present at developing synapses where it can partici- pate in their normal maturation

Ruthazer, Edward

35

FRK Inhibits Migration and Invasion of Human Glioma Cells by Promoting N-cadherin/?-catenin Complex Formation.  

PubMed

Fyn-related kinase (FRK), a member of Src-related tyrosine kinases, is recently reported to function as a potent tumor suppressor in several cancer types. Our previous study has also shown that FRK over-expression inhibited the migration and invasion of glioma cells. However, the mechanism of FRK effect on glioma cell migration and invasion, a feature of human malignant gliomas, is still not clear. In this study, we found that FRK over-expression increased the protein level of N-cadherin, but not E-cadherin. Meanwhile, FRK over-expression promoted ?-catenin translocation to the plasma membrane, where it formed complex with N-cadherin, while decreased ?-catenin level in the nuclear fraction. In addition, down-regulation of N-cadherin by siRNA promoted the migration and invasion of glioma U251 and U87 cells and abolished the inhibitory effect of FRK on glioma cell migration and invasion. In summary, these results indicate that FRK inhibits migration and invasion of human glioma cells by promoting N-cadherin/?-catenin complex formation. PMID:24969324

Shi, Qiong; Song, Xu; Wang, Jun; Gu, Jia; Zhang, Weijian; Hu, Jinxia; Zhou, Xiuping; Yu, Rutong

2015-01-01

36

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

SciTech Connect

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 {beta}-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 [Department of Biochemistry, University of Nebraska, Lincoln, NE 68588 (United States)] [Department of Biochemistry, University of Nebraska, Lincoln, NE 68588 (United States); Oakley, Gregory G.; Wahl, James K. [Department of Oral Biology, University of Nebraska College of Dentistry, Lincoln, NE 68588 (United States)] [Department of Oral Biology, University of Nebraska College of Dentistry, Lincoln, NE 68588 (United States); Simpson, Melanie A., E-mail: msimpson2@unl.edu [Department of Biochemistry, University of Nebraska, Lincoln, NE 68588 (United States); Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198 (United States)

2011-05-01

37

Suppression of tumorigenicity by plakoglobin: an augmenting effect of N- cadherin  

PubMed Central

Plakoglobin is a major component of the submembranal plaque of adherens junctions and desmosomes in mammalian cells. It is closely related to the Drosophila segment polarity gene armadillo which has a role in the transduction of transmembrane signals that regulate cell fate. Like its close homologue beta-catenin, plakoglobin can associate with the product of the tumor suppressor gene APC that is linked to human colon cancer. We have studied the effect of plakoglobin overexpression, and the cooperation between plakoglobin and N-cadherin, on the morphology and tumorigenic ability of cells either lacking, or expressing cadherin and alpha- and beta-catenin. Overexpression of plakoglobin in SV40- transformed 3T3 (SVT2) cells suppressed the tumorigenicity of the cells in syngeneic mice. Transfection with N-cadherin conferred an epithelial phenotype on the cell culture, but had no significant effect on the tumorigenicity of the cells. Cotransfection of plakoglobin and N- cadherin into SVT2 cells, however, was considerably more effective in tumor suppression than plakoglobin overexpression alone. Finally, transfection of plakoglobin into a human renal carcinoma cell line that expresses neither cadherins nor plakoglobin, or alpha-and beta-catenin, resulted in a dose-dependent suppression of tumor formation by these cells in nude mice. Plakoglobin, in these cells, did not exhibit junctional localization and was diffusely distributed in the cytoplasm, with a significant amount of the protein also localized in the nucleus. The results suggest that plakoglobin can efficiently suppress the tumorigenicity of cells in the presence of, or independently of the cadherin-catenin complex. PMID:8601608

1996-01-01

38

Alterations in cell adhesion proteins and cardiomyopathy  

PubMed Central

Cell adhesive junction is specialized intercellular structure composed of cell adhesion proteins. They are essential to connect adjacent heart muscle cell and make heart contraction effectively and properly. Clinical and genetic studies have revealed close relationship between cell adhesive proteins and the occurrence of various cardiomyopathies. Here we will review recent development on the disease phenotype, potential cellular and molecular mechanism related to cell adhesion molecules, with particular disease pathogenesis learned from genetic manipulated murine models. PMID:24944760

Li, Jifen

2014-01-01

39

Inflammatory bowel disease and adenomas in mice expressing a dominant negative N-cadherin.  

PubMed

Cadherins mediate cell adhesion and are essential for normal development. Embryonic stem cells were transfected with a dominant negative N-cadherin mutant (NCAD delta) under the control of promoters active in small intestinal epithelial cells and then introduced into C57BL/6 mouse blastocysts. Analysis of adult chimeric mice revealed that expression of NCAD delta along the entire crypt-villus axis, but not in the villus epithelium alone, produced an inflammatory bowel disease resembling Crohn's disease. NCAD delta perturbed proliferation, migration, and death programs in crypts, which lead to adenomas. This model provides insights about cadherin function in an adult organ and the factors underlying inflammatory bowel disease and intestinal neoplasia. PMID:7502046

Hermiston, M L; Gordon, J I

1995-11-17

40

Molecular mechanics of mussel adhesion proteins  

NASA Astrophysics Data System (ADS)

Mussel foot protein (mfp), a natural glue produced by marine mussel, is an intriguing material because of its superior ability for adhesion in various environments. For example, a very small amount of this material is sufficient to affix a mussel to a substrate in water, providing structural support under extreme forces caused by the dynamic effects of waves. Towards a more complete understanding of its strength and underwater workability, it is necessary to understand the microscropic mechanisms by which the protein structure interacts with various substrates. However, none of the mussel proteins' structure is known, preventing us from directly using atomistic modeling to probe their structural and mechanical properties. Here we use an advanced molecular sampling technique to identify the molecular structures of two mussel foot proteins (mfp-3 and mfp-5) and use those structures to study their mechanics of adhesion, which is then incorporated into a continuum model. We calculate the adhesion energy of the mussel foot protein on a silica substrate, compute the adhesion strength based on results obtained from molecular modeling, and compare with experimental data. Our results show good agreement with experimental measurements, which validates the multiscale model. We find that the molecular structure of the folded mussel foot protein (ultimately defined by its genetic sequence) favors strong adhesion to substrates, where L-3,4-dihydroxyphenylalanine (or DOPA) protein subunits work in a cooperative manner to enhance adhesion. Our experimental data suggests a peak attachment force of 0.4±0.1 N, which compares favorably with the prediction from the multiscale model of Fc=0.21-0.33 N. The principles learnt from those results could guide the fabrication of new interfacial materials (e.g. composites) to integrate organic with inorganic surfaces in an effective manner.

Qin, Zhao; Buehler, Markus J.

2014-01-01

41

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. PMID:21423400

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

2010-01-01

42

Trim28 Contributes to EMT via Regulation of E-Cadherin and N-Cadherin in Lung Cancer Cell Lines  

PubMed Central

In previous work, we demonstrated that transcription factor Trim28 (Tripartite motif containing 28) plays a tumor-suppressor role in early-staged adenocarcinoma of the lung due to its ability to restrain transcription of cell cycle-regulating genes. Herein we examine Trim28's role in the epithelial-to-mesenchymal transition (EMT) which is strongly implicated in cancer metastasis. We found that Trim28 plays a role in TGF-?-induced EMT in non-small cell lung cancer cells. Silencing Trim28 with inhibitory RNAs alters the expression of numerous EMT markers, such as E-cadherin and N-cadherin, whereas overexpression of Trim28 has an opposite effect. Trim28 expression is induced following TGF-? treatment at both protein and mRNA levels. Trim28 deficiency impairs TGF-?-induced EMT and decreases cell migration and invasion. Finally, we demonstrate that the expression of Trim28 affects the acetylation and methylation of histones on E-cadherin and N-cadherin promoters. These results suggest that Trim28 contributes to EMT and might be important for tumor metastasis in lung cancer. Taken together with our previous work these results suggest a model in which Trim28 is a tumor suppressor early in the transformation process in lung cancer, but in later stages it functions as an oncogene. PMID:24983967

Chen, Lu; Muñoz-Antonia, Teresita; Cress, W. Douglas

2014-01-01

43

Activity-dependent regulation of {beta}-catenin via {epsilon}-cleavage of N-cadherin  

SciTech Connect

N-cadherin is essential for excitatory synaptic contact in the hippocampus. Presenilin 1 (PS1) is located at sites of synaptic contact, forming a complex with N-cadherin and {beta}-catenin. Here, we report that human N-cadherin is cleaved by PS1/{gamma}-secretase in response to physiological concentration of glutamate (Glu) stimulation, yielding a fragment Ncad/CTF2. The expression of Ncad/CTF2 in neuronal cells led to its translocation to the nucleus, and caused a prominent enhancement of cytoplasmic and nuclear {beta}-catenin levels in a cell-cell contact dependent manner, via following mechanisms: 1, inhibition of {beta}-catenin phosphorylation; 2, transactivation of {beta}-catenin; and 3, inhibition of N-cadherin transcription, and finally enhanced {beta}-catenin nuclear signaling. Since the regulation of cellular {beta}-catenin level is essential for synaptic function, disruption in the cleavage of N-cadherin may be causally linked to the synaptic dysfunction associated with Alzheimer's disease (AD)

Uemura, Kengo [Horizontal Medical Research Organization, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Kihara, Takeshi [Department of Neuroscience for Drug Discovery, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8507 (Japan); Kuzuya, Akira [Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Okawa, Katsuya [Horizontal Medical Research Organization, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan); Nishimoto, Takaaki [Department of Neuroscience for Drug Discovery, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8507 (Japan); Bito, Haruhiko [Department of Neurochemistry, University of Tokyo, Graduate School of Medicine, Tokyo 113-8654 (Japan); Ninomiya, Haruaki [Department of Neurobiology, Tottori University Faculty of Medicine, Yonago 683-8503 (Japan); Sugimoto, Hachiro [Department of Neuroscience for Drug Discovery, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8507 (Japan); Kinoshita, Ayae [Horizontal Medical Research Organization, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan) and Department of Health Science, Faculty of Medicine, Kyoto University, Kyoto 606-8507 (Japan)]. E-mail: akinoshita@hs.med.kyoto-u.ac.jp; Shimohama, Shun [Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto 606-8507 (Japan)

2006-07-07

44

Protein Kinase C ? (PKC?) Is Required for Protein Tyrosine Phosphatase ? (PTP?)Dependent Neurite Outgrowth  

Microsoft Academic Search

Protein tyrosine phosphatase ? (PTP?) is an adhesion molecule in the immunoglobulin superfamily and is expressed in the developing nervous system. We have shown that PTP? can promote neurite outgrowth of retinal ganglion cells and it regulates neurite outgrowth mediated by N-cadherin (S. M. Burden-Gulley and S. M. Brady-Kalnay, 1999, J. Cell Biol. 144, 1323–1336). We previously demonstrated that PTP?

Jullia A. Rosdahl; Tracy L. Mourton; Susann M. Brady-Kalnay

2002-01-01

45

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. PMID:17988630

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

46

N-cadherin deficiency impairs pericyte recruitment, and not endothelial differentiation or sprouting, in embryonic stem cell-derived angiogenesis  

SciTech Connect

Endothelial cells express two classical cadherins, VE-cadherin and N-cadherin. VE-cadherin is absolutely required for vascular morphogenesis, but N-cadherin is thought to participate in vessel stabilization by interacting with periendothelial cells during vessel formation. However, recent data suggest a more critical role for N-cadherin in endothelium that would regulate angiogenesis, in part by controlling VE-cadherin expression. In this study, we have assessed N-cadherin function in vascular development using an in vitro model derived from embryonic stem (ES) cell differentiation. We show that pluripotent ES cells genetically null for N-cadherin can differentiate normally into endothelial cells. In addition, sprouting angiogenesis was unaltered, suggesting that N-cadherin is not essential for the early events of angiogenesis. However, the lack of N-cadherin led to an impairment in pericyte covering of endothelial outgrowths. We conclude that N-cadherin is necessary neither for vasculogenesis nor proliferation and migration of endothelial cells but is required for the subsequent maturation of endothelial sprouts by interacting with pericytes.

Tillet, Emmanuelle [Laboratoire de Developpement et Vieillissement de l'Endothelium, INSERM EMI 0219, CEA, Joseph Fourier University, Grenoble (France)]. E-mail: emmanuelle.tillet@cea.fr; Vittet, Daniel [Laboratoire de Developpement et Vieillissement de l'Endothelium, INSERM EMI 0219, CEA, Joseph Fourier University, Grenoble (France); Feraud, Olivier [Laboratoire de Developpement et Vieillissement de l'Endothelium, INSERM EMI 0219, CEA, Joseph Fourier University, Grenoble (France); Moore, Robert [Max-Planck Institute for Immunobiology, Stuebeweg 51, D-79108 Freiburg (Germany); Kemler, Rolf [Max-Planck Institute for Immunobiology, Stuebeweg 51, D-79108 Freiburg (Germany); Huber, Philippe [Laboratoire de Developpement et Vieillissement de l'Endothelium, INSERM EMI 0219, CEA, Joseph Fourier University, Grenoble (France)

2005-11-01

47

Hydrogels that mimic developmentally relevant matrix and N-cadherin interactions enhance MSC chondrogenesis.  

PubMed

Methacrylated hyaluronic acid (HA) hydrogels provide a backbone polymer with which mesenchymal stem cells (MSCs) can interact through several cell surface receptors that are expressed by MSCs, including CD44 and CD168. Previous studies showed that this 3D hydrogel environment supports the chondrogenesis of MSCs, and here we demonstrate through functional blockade that these specific cell-material interactions play a role in this process. Beyond matrix interactions, cadherin molecules, a family of transmembrane glycoproteins, play a critical role in tissue development during embryogenesis, and N-cadherin is a key factor in mediating cell-cell interactions during mesenchymal condensation and chondrogenesis. In this study, we functionalized HA hydrogels with N-cadherin mimetic peptides and evaluated their role in regulating chondrogenesis and cartilage matrix deposition by encapsulated MSCs. Our results show that conjugation of cadherin peptides onto HA hydrogels promotes both early chondrogenesis of MSCs and cartilage-specific matrix production with culture, compared with unmodified controls or those with inclusion of a scrambled peptide domain. This enhanced chondrogenesis was abolished via treatment with N-cadherin-specific antibodies, confirming the contribution of these N-cadherin peptides to chondrogenesis. Subcutaneous implantation of MSC-seeded constructs also showed superior neocartilage formation in implants functionalized with N-cadherin mimetic peptides compared with controls. This study demonstrates the inherent biologic activity of HA-based hydrogels, as well as the promise of biofunctionalizing HA hydrogels to emulate the complexity of the natural cell microenvironment during embryogenesis, particularly in stem cell-based cartilage regeneration. PMID:23733927

Bian, Liming; Guvendiren, Murat; Mauck, Robert L; Burdick, Jason A

2013-06-18

48

Aberrant methylation accounts for cell adhesion-related gene silencing during 3-methylcholanthrene and diethylnitrosamine induced multistep rat lung carcinogenesis associated with overexpression of DNA methyltransferases 1 and 3a  

SciTech Connect

To evaluate the significance of alterations in cell adhesion-related genes methylation during lung multistep carcinogenesis induced by the genotoxic carcinogens 3-methylcholanthrene (MCA) and diethylnitrosamine (DEN), tissue samples microdissected from MCA/DEN-induced rat lung carcinogenesis model were subjected to methylation-specific PCR to evaluate the DNA methylation status of CADM1, TIMP3, E-cadherin and N-cadherin. Immunohistochemistry was used to determine protein expression of CADM1, TIMP3, N-cadherin and the DNA methyltransferases (DNMTs) 1, 3a and 3b. E-cadherin hypermethylation was not detected in any tissue. CADM1, TIMP3 and N-cadherin hypermethylation was correlated with the loss of their protein expression during the progression of pathologic lesions. The prevalence of DNA methylation of at least one gene and the average number of methylated genes increased with the histological progression. DNMT1 and DNMT3a protein expression increased progressively during the stages of lung carcinogenesis, whereas DNMT3b overexpression was only found in several samples. Furthermore, DNMT1 protein expression levels were correlated with CADM1 methylation, and DNMT3a protein expression levels were correlated with CADM1, TIMP3 and N-cadherin methylation. The average number of methylated genes during carcinogenesis was significantly correlated with DNMT1 and DNMT3a protein expression levels. Moreover, mRNA expression of CADM1 significantly increased after treatment with DNMT inhibitor 5-aza-2'-deoxycytidine in CADM1-methylated primary tumor cell lines. Our findings suggest that an accumulation of hypermethylation accounts for cell adhesion-related gene silencing is associated with dynamic changes in the progression of MCA/DEN-induced rat lung carcinogenesis. We suggest that DNMT1 and DNMT3a protein overexpression may be responsible for this aberrant DNA methylation.

Liu Wenbin; Cui Zhihong; Ao Lin; Zhou Ziyuan; Zhou Yanhong; Yuan Xiaoyan; Xiang Yunlong; Liu Jinyi, E-mail: jinyiliutmmu@163.com; Cao Jia, E-mail: caojia1962@126.com

2011-02-15

49

N-cadherin{sup +} HSCs in fetal liver exhibit higher long-term bone marrow reconstitution activity than N-cadherin{sup -} HSCs  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer High N-cad expression was detected in E12.5 mouse FL LT-HSCs (EPCR{sup +} LSK cells). Black-Right-Pointing-Pointer Immunohistochemically, N-cad{sup +} HSCs co-localized with sinusoidal ECs (Lyve-1{sup +} cells) in E12.5 FL, but these gradually detached in E15.5 and E18.5 FL. Black-Right-Pointing-Pointer N-cad{sup +} LSK cells in E12.5 FL exhibited higher LTR activity versus N-cad{sup -} LSK cells, which decreased in E15.5 and E18.5. Black-Right-Pointing-Pointer N-cad expression may confer high LTR activity to HSCs by facilitating interactions with the perisinusoidal niche in FL. -- Abstract: Adult hematopoietic stem cells (HSCs) are maintained in a microenvironment known as the stem cell niche. The regulation of HSCs in fetal liver (FL) and their niche, however, remains to be elucidated. In this study, we investigated the role of N-cadherin (N-cad) in the maintenance of HSCs during FL hematopoiesis. By using anti-N-cad antibodies (Abs) produced by our laboratory, we detected high N-cad expression in embryonic day 12.5 (E12.5) mouse FL HSCs, but not in E15.5 and E18.5 FL. Immunofluorescence staining revealed that N-cad{sup +}c-Kit{sup +} and N-cad{sup +} endothelial protein C receptor (EPCR){sup +} HSCs co-localized with Lyve-1{sup +} sinusoidal endothelial cells (ECs) in E12.5 FL and that some of these cells also expressed N-cad. However, N-cad{sup +} HSCs were also observed to detach from the perisinusoidal niche at E15.5 and E18.5, concomitant with a down-regulation of N-cad and an up-regulation of E-cadherin (E-cad) in hepatic cells. Moreover, EPCR{sup +} long-term (LT)-HSCs were enriched in the N-cad{sup +}Lin{sup -}Sca-1{sup +}c-Kit{sup +} (LSK) fraction in E12.5 FL, but not in E15.5 or E18.5 FL. In a long-term reconstitution (LTR) activity assay, higher engraftment associated with N-cad{sup +} LSK cells versus N-cad{sup -} LSK cells in E12.5 FL when transplanted into lethally irradiated recipient mice. However, the higher engraftment of N-cad{sup +} LSK cells decreased subsequently in E15.5 and E18.5 FL. It is possible that N-cad expression conferred higher LTR activity to HSCs by facilitating interactions with the perisinusoidal niche, especially at E12.5. The down-regulation of N-cad during FL hematopoiesis may help us better understand the regulation and mobility of HSCs before migration into BM.

Toyama, Hirofumi; Arai, Fumio; Hosokawa, Kentaro; Ikushima, Yoshiko Matsumoto [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan)] [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Suda, Toshio, E-mail: sudato@z3.keio.jp [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan)] [Department of Cell Differentiation, The Sakaguchi Laboratory of Developmental Biology, School of Medicine, Keio University, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan)

2012-11-23

50

Investigation of modified cottonseed protein adhesives for wood composites  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several modified cottonseed protein isolates were studied and compared to corresponding soy protein isolates for their adhesive properties when bonded to wood composites. Modifications included treatments with alkali, guanidine hydrochloride, sodium dodecyl sulfate (SDS), and urea. Wood composites...

51

Similarities between heterophilic and homophilic cadherin adhesion.  

PubMed

The mechanism that drives the segregation of cells into tissue-specific subpopulations during development is largely attributed to differences in intercellular adhesion. This process requires the cadherin family of calcium-dependent glycoproteins. A widely held view is that protein-level discrimination between different cadherins on cell surfaces drives this sorting process. Despite this postulated molecular selectivity, adhesion selectivity has not been quantitatively verified at the protein level. In this work, molecular force measurements and bead aggregation assays tested whether differences in cadherin bond strengths could account for cell sorting in vivo and in vitro. Studies were conducted with chicken N-cadherin, canine E-cadherin, and Xenopus C-cadherin. Both qualitative bead aggregation and quantitative force measurements show that the cadherins cross-react. Furthermore, heterophilic adhesion is not substantially weaker than homophilic adhesion, and the measured differences in adhesion do not correlate with cell sorting behavior. These results suggest that the basis for cell segregation during morphogenesis does not map exclusively to protein-level differences in cadherin adhesion. PMID:17023539

Prakasam, A K; Maruthamuthu, V; Leckband, D E

2006-10-17

52

ADAM10 mediates N-cadherin ectodomain shedding during retinal ganglion cell differentiation in primary cultured retinal cells from the developing chick retina.  

PubMed

Here, we examined the role of ADAM10 during retinal cell differentiation in retinal sections and in vitro cultures of developing chick retinal cells from embryonic day 6 (ED6). Immunohistochemistry showed that ADAM10 is abundantly expressed in the inner zone of neuroblastic layer at ED5, and it becomes more highly expressed in the ganglion cell layer at ED7 and ED9. Western blotting confirmed that ADAM10 was expressed as an inactive pro-form that was processed to a shorter, active form in control cultured cells, but in cultures treated with an ADAM10 inhibitor (GI254023X) and ADAM10-specific siRNA, the level of mature ADAM10 decreased. Phase-contrast microscopy showed that long neurite extensions were present in untreated cultures 24?h after plating, whereas cultures treated with GI254023X showed significant decreases in neurite extension. Immunofluorescence staining revealed that there were far fewer differentiated ganglion cells in ADAM10 siRNA and GI254023X-treated cultures compared to controls, whereas the photoreceptor cells were unaltered. The Pax6 protein was more strongly detected in the differentiated ganglion cells of control cultures compared to ADAM10 siRNA and GI254023X-treated cultures. N-cadherin ectodomain shedding was apparent in control cultures after 24 h, when ganglion cell differentiation was observed, but ADAM10 siRNA and GI254023X treatment inhibited these processes. In contrast, N-cadherin staining was strongly detected in photoreceptor cells regardless of ADAM10 siRNA and GI254023X treatment. Taken together, these data indicate that the inhibition of ADAM10 can inhibit Pax6 expression and N-cadherin ectodomain shedding in retinal cells, possibly affecting neurite outgrowth and ganglion cell differentiation. PMID:23129104

Paudel, Sharada; Kim, Yeoun-Hee; Huh, Man-Il; Kim, Song-Ja; Chang, Yongmin; Park, Young Jeung; Lee, Kyoo Won; Jung, Jae-Chang

2013-04-01

53

c-Yes regulates cell adhesion at the apical ectoplasmic specialization-blood-testis barrier axis via its effects on protein recruitment and distribution  

PubMed Central

During spermatogenesis, extensive restructuring takes place at the cell-cell interface since developing germ cells migrate progressively from the basal to the adluminal compartment of the seminiferous epithelium. Since germ cells per se are not motile cells, their movement relies almost exclusively on the Sertoli cell. Nonetheless, extensive exchanges in signaling take place between these cells in the seminiferous epithelium. c-Yes, a nonreceptor protein tyrosine kinase belonging to the Src family kinases (SFKs) and a crucial signaling protein, was recently shown to be upregulated at the Sertoli cell-cell interface at the blood-testis barrier (BTB) at stages VIII–IX of the seminiferous epithelial cycle of spermatogenesis. It was also highly expressed at the Sertoli cell-spermatid interface known as apical ectoplasmic specialization (apical ES) at stage V to early stage VIII of the epithelial cycle during spermiogenesis. Herein, it was shown that the knockdown of c-Yes by RNAi in vitro and in vivo affected both Sertoli cell adhesion at the BTB and spermatid adhesion at the apical ES, causing a disruption of the Sertoli cell tight junction-permeability barrier function, germ cell loss from the seminiferous epithelium, and also a loss of spermatid polarity. These effects were shown to be mediated by changes in distribution and/or localization of adhesion proteins at the BTB (e.g., occludin, N-cadherin) and at the apical ES (e.g., nectin-3) and possibly the result of changes in the underlying actin filaments at the BTB and the apical ES. These findings implicate that c-Yes is a likely target of male contraceptive research. PMID:23169788

Xiao, Xiang; Mruk, Dolores D.

2013-01-01

54

Biomimetic soy protein nanocomposites with calcium carbonate crystalline arrays for use as wood adhesive  

E-print Network

and bonding strength of soy protein adhesives. Glue strength of soy protein hybrid adhesive was higher than 6 2010 Available online 21 March 2010 Keywords: Wood glue Calcium carbonate Gecko adhesion Soy protein the adhesion strength. The structure and morphology of the adhesive and its fracture bonding interface

55

Adhesion properties of soy protein with fiber cardboard  

Microsoft Academic Search

Adhesion properties of soy protein isolate (SPI) on fiber cardboard and effects of press conditions, pre-pressing drying time,\\u000a and protein concentrations on gluing strength were investigated. Shear strength increased as press time, press pressure, and\\/or\\u000a press temperature increased. The effect of temperature on shear strength became more significant at high press pressure. The\\u000a shear strength of the SPI adhesive on

Zhikai Zhong; X. Susan Sun; Xiaohua Fang; Jo A. Ratto

2001-01-01

56

Nanoscale adhesion, friction and wear of proteins on polystyrene.  

PubMed

Protein layers are routinely deployed on biomaterials and biological micro/nanoelectromechanical systems (bioMEMS/NEMS) as a functional layer allowing for specific molecular recognition, binding properties or to facilitate biocompatibility. In addition, uncoated biomaterial surfaces will have uncontrolled protein layers adsorbing to the surface within seconds of implantation, so a pre-defined protein layer will improve the host response. Implanted biomaterials also experience micromotion over time which may degrade any surface protein layers. Degradation of these protein layers may lead to system failure or an unwanted immune response. Therefore, it is important to characterize the interfacial properties of proteins on biomaterial surfaces. In this study, the nanoscale adhesion, friction and wear properties of proteins adsorbed to a spin coated polystyrene surface were measured using atomic force microscopy (AFM) in deionized (DI) water and phosphate buffered saline. Adhesion, friction and wear have been measured for bovine serum albumin (BSA), collagen, fibronectin and streptavidin (STA) in DI water and PBS as a function of protein concentration. These proteins were chosen due to their importance and widespread application in the biotechnology field. Adhesion and friction were also measured for BSA and STA at two different temperatures and different pH values to simulate a biological environment. Based on this study, adhesion, friction and wear mechanisms of the different proteins are discussed. PMID:23085687

Bhushan, Bharat; Utter, Jason

2013-02-01

57

LINKIN, a new transmembrane protein necessary for cell adhesion.  

PubMed

In epithelial collective migration, leader and follower cells migrate while maintaining cell-cell adhesion and tissue polarity. We have identified a conserved protein and interactors required for maintaining cell adhesion during a simple collective migration in the developing C. elegans male gonad. LINKIN is a previously uncharacterized, transmembrane protein conserved throughout Metazoa. We identified seven atypical FG-GAP domains in the extracellular domain, which potentially folds into a ?-propeller structure resembling the ?-integrin ligand-binding domain. C. elegans LNKN-1 localizes to the plasma membrane of all gonadal cells, with apical and lateral bias. We identified the LINKIN interactors RUVBL1, RUVBL2, and ?-tubulin by using SILAC mass spectrometry on human HEK 293T cells and testing candidates for lnkn-1-like function in C. elegans male gonad. We propose that LINKIN promotes adhesion between neighboring cells through its extracellular domain and regulates microtubule dynamics through RUVBL proteins at its intracellular domain. PMID:25437307

Kato, Mihoko; Chou, Tsui-Fen; Yu, Collin Z; DeModena, John; Sternberg, Paul W

2014-01-01

58

Clinical usefulness of immunohistochemistry for plakoglobin, N-cadherin, and connexin-43 in the diagnosis of arrhythmogenic right ventricular cardiomyopathy  

PubMed Central

Diagnosing arrhythmogenic right ventricular cardiomyopathy (ARVC) is often challenging because no single diagnostic tool is available to detect the disease. We evaluated whether analysis of plakoglobin, N-cadherin, and connexin-43 immunoreactivity can be used as a significant test in diagnosis of ARVC. We selected subjects with suspicion of ARVC (n=22) in patients who underwent endomyocardial biopsy (EMB) in Kyungpook National University Hospital (n=1326). The patients (n=22) were classified into definite ARVC patients (n=17) and borderline ARVC (n=5). We selected control subjects (n=20) who were autopsied and died of non-cardiac disease. Hematoxylin-eosin, Masson’s trichrome, and immunohistochemical stains for plakoglobin, N-cadherin, and connexin-43 were used for all specimens. Reduced immunoreactivity of plakoglobin was observed in 13 (76%) of the 17 patients with a definite ARVC and in 4 (80%) of the 5 patients with a borderline ARVC. All subjects displayed no significant reduction of the immunoreactivity for connexin-43 as well as for N-cadherin. Our investigation revealed that the immunohistochemical analysis for plakoglobin had an accuracy of 81%, 76% sensitivity, and 84% specificity in diagnosis of ARVC. Results of our study showed that the immunohistochemical analysis of plakoglobin had a relatively high sensitivity and specificity in ARVC, but immunohistochemistry for plakoglobin alone could not be relied upon as a diagnostic test for ARVC. We confirmed that N-cadherin and connexin-43 had no diagnostic value in ARVC. PMID:24294380

Kwon, Yong-Seop; Park, Tae In; Cho, Yongkeun; Bae, Myung Hwan; Kim, Sunzoo

2013-01-01

59

Regulation of Embryonic Cell Adhesion by the Prion Protein  

PubMed Central

Prion proteins (PrPs) are key players in fatal neurodegenerative disorders, yet their physiological functions remain unclear, as PrP knockout mice develop rather normally. We report a strong PrP loss-of-function phenotype in zebrafish embryos, characterized by the loss of embryonic cell adhesion and arrested gastrulation. Zebrafish and mouse PrP mRNAs can partially rescue this knockdown phenotype, indicating conserved PrP functions. Using zebrafish, mouse, and Drosophila cells, we show that PrP: (1) mediates Ca+2-independent homophilic cell adhesion and signaling; and (2) modulates Ca+2-dependent cell adhesion by regulating the delivery of E-cadherin to the plasma membrane. In vivo time-lapse analyses reveal that the arrested gastrulation in PrP knockdown embryos is due to deficient morphogenetic cell movements, which rely on E-cadherin–based adhesion. Cell-transplantation experiments indicate that the regulation of embryonic cell adhesion by PrP is cell-autonomous. Moreover, we find that the local accumulation of PrP at cell contact sites is concomitant with the activation of Src-related kinases, the recruitment of reggie/flotillin microdomains, and the reorganization of the actin cytoskeleton, consistent with a role of PrP in the modulation of cell adhesion via signaling. Altogether, our data uncover evolutionarily conserved roles of PrP in cell communication, which ultimately impinge on the stability of adherens cell junctions during embryonic development. PMID:19278297

Schrock, Yvonne; Geiss, Corinna; Luncz, Lydia; Thomanetz, Venus; Stuermer, Claudia A. O

2009-01-01

60

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  

SciTech Connect

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 12 days. 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. - Highlights: ? Influence of Cr(VI) on the Sertoli cell barrier and on junctional proteins ? Use of cultured seminiferous tubules in bicameral chambers ? Low concentrations of Cr(VI) (10 ?g/l) altered the trans-epithelial resistance. ? Cr(VI) did not alter claudin-11 and N-cadherin. ? Cr(VI) delocalized connexin 43 from the membrane to the cytoplasm of Sertoli cells.

Carette, Diane [INSERM U 1065, Team 5 “Physiopathology of Germ Cell Control: Genomic and Non Genomic Mechanisms” C3M, University of Nice Sophia Antipolis, Nice (France); UMR S775, University Paris Descartes, 45 rue des Saints Pères, 75006, Paris (France); Perrard, Marie-Hélène, E-mail: marie-helene.durand@ens-lyon.fr [Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon I, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon (France); Prisant, Nadia [University of Versailles/St Quentin-en-Yvelines (France); UMR S775, University Paris Descartes, 45 rue des Saints Pères, 75006, Paris (France); Gilleron, Jérome; Pointis, Georges [INSERM U 1065, Team 5 “Physiopathology of Germ Cell Control: Genomic and Non Genomic Mechanisms” C3M, University of Nice Sophia Antipolis, Nice (France); Segretain, Dominique [University of Versailles/St Quentin-en-Yvelines (France); UMR S775, University Paris Descartes, 45 rue des Saints Pères, 75006, Paris (France); Durand, Philippe [Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Lyon I, CNRS, INRA, Ecole Normale Supérieure de Lyon, Lyon (France); Kallistem SAS Ecole Normale Supérieure de Lyon, Lyon (France)

2013-04-01

61

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. PMID:21705647

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

2011-01-01

62

Protein kinase C activation stimulates mesenchymal stem cell adhesion through activation of focal adhesion kinase.  

PubMed

Emerging evidence suggests that cell therapy with mesenchymal stem cells (MSCs) has beneficial effects on the injured heart. However, the decreased survival and/or adhesion of MSCs under ischemic conditions limits the application of cell transplantation as a therapeutic modality. We investigated a potential method of increasing the adhesion ability of MSCs to improve their efficacy in the ischemic heart. Treatment of MSCs with PKC activator, phorbol 12-myristate 13-acetate (PMA), increased cell adhesion and spreading in a dose-dependent method and significantly decreased detachment. When MSCs were treated with PKC inhibitor, that is, rottlerin, adhesion of MSCs was slightly diminished, and detachment was also decreased compared to the treatment with PMA. MSCs treated with both PMA and rottlerin behaved similarly to normal controls. In 3D matrix cardio gel, treatment with PMA increased the number of MSCs compared to the control group and MSCs treated with rottlerin. Expressions of focal adhesion kinase, cytoskeleton-associated proteins, and integrin subunits were clearly demonstrated in PMA-treated MSCs by immunoblotting and/or immunocytochemistry. The effect of PKC activator treatment on MSCs was validated in vivo. Following injection into rat hearts, the PMA-treated MSCs exhibited significantly higher retention in infarcted myocardium compared to the MSC group. Infarct size, fibrosis area, and apoptotic cells were reduced, and cardiac function was improved in rat hearts injected with PMA-treated MSCs compared to sham and/or MSC-implanted group. These results indicate that PKC activator is a potential target for niche manipulation to enhance adhesion of MSCs for cardiac regeneration. PMID:23006313

Song, Byeong-Wook; Chang, Woochul; Hong, Bum-Kee; Kim, Il-Kwon; Cha, Min-Ji; Lim, Soyeon; Choi, Eun Ju; Ham, Onju; Lee, Se-Yeon; Lee, Chang Youn; Park, Jun-Hee; Choi, Eunmi; Song, Heesang; Jang, Yangsoo; Hwang, Ki-Chul

2013-01-01

63

Polymeric Thin Films That Resist the Adsorption of Proteins and the Adhesion of Bacteria  

E-print Network

Polymeric Thin Films That Resist the Adsorption of Proteins and the Adhesion of Bacteria Robert G of thin polymeric films that resist the adsorption of proteins and the adhesion of bacteria to an extent.Polyaminesfunctionalizedwithacetylchlorideproducedfilmsthatresistedtheadsorption of protein and the adhesion of bacteria to a useful extent. Functionalization of the polyamine with acyl

Prentiss, Mara

64

Synergistic Control of Cellular Adhesion by Transmembrane 9 Proteins  

PubMed Central

The transmembrane 9 (TM9) family of proteins contains numerous members in eukaryotes. Although their function remains essentially unknown in higher eukaryotes, the Dictyostelium discoideum Phg1a TM9 protein was recently reported to be essential for cellular adhesion and phagocytosis. Herein, the function of Phg1a and of a new divergent member of the TM9 family called Phg1b was further investigated in D. discoideum. The phenotypes of PHG1a, PHG1b, and PHG1a/PHG1b double knockout cells revealed that Phg1a and Phg1b proteins play a synergistic but not redundant role in cellular adhesion, phagocytosis, growth, and development. Complementation analysis supports a synergistic regulatory function rather than a receptor role for Phg1a and Phg1b proteins. Together, these results suggest that Phg1 proteins act as regulators of cellular adhesion, possibly by controlling the intracellular transport in the endocytic pathway and the composition of the cell surface. PMID:12857872

Benghezal, Mohammed; Cornillon, Sophie; Gebbie, Leigh; Alibaud, Laeticia; Brückert, Franz; Letourneur, François; Cosson, Pierre

2003-01-01

65

Linking molecular affinity and cellular specificity in cadherin-mediated adhesion  

PubMed Central

Many cell–cell adhesive events are mediated by the dimerization of cadherin proteins presented on apposing cell surfaces. Cadherin-mediated processes play a central role in the sorting of cells into separate tissues in vivo, but in vitro assays aimed at mimicking this behavior have yielded inconclusive results. In some cases, cells that express different cadherins exhibit homotypic cell sorting, forming separate cell aggregates, whereas in other cases, intermixed aggregates are formed. A third pattern is observed for mixtures of cells expressing either N- or E-cadherin, which form distinct homotypic aggregates that adhere to one another through a heterotypic interface. The molecular basis of cadherin-mediated cell patterning phenomena is poorly understood, in part because the relationship between cellular adhesive specificity and intermolecular binding free energies has not been established. To clarify this issue, we have measured the dimerization affinities of N-cadherin and E-cadherin. These proteins are similar in sequence and structure, yet are able to mediate homotypic cell patterning behavior in a variety of tissues. N-cadherin is found to form homodimers with higher affinity than does E-cadherin and, unexpectedly, the N/E-cadherin heterophilic binding affinity is intermediate in strength between the 2 homophilic affinities. We can account for observed cell aggregation behaviors by using a theoretical framework that establishes a connection between molecular affinities and cell–cell adhesive specificity. Our results illustrate how graded differences between different homophilic and heterophilic cadherin dimerizaton affinities can result in homotypic cell patterning and, more generally, show how proteins that are closely related can, nevertheless, be responsible for highly specific cellular adhesive behavior. PMID:19553217

Katsamba, P.; Carroll, K.; Ahlsen, G.; Bahna, F.; Vendome, J.; Posy, S.; Rajebhosale, M.; Price, S.; Jessell, T. M.; Ben-Shaul, A.; Shapiro, L.; Honig, Barry H.

2009-01-01

66

Sip1 mediates an E-cadherin-to-N-cadherin switch during cranial neural crest EMT  

PubMed Central

The neural crest, an embryonic stem cell population, initially resides within the dorsal neural tube but subsequently undergoes an epithelial-to-mesenchymal transition (EMT) to commence migration. Although neural crest and cancer EMTs are morphologically similar, little is known regarding conservation of their underlying molecular mechanisms. We report that Sip1, which is involved in cancer EMT, plays a critical role in promoting the neural crest cell transition to a mesenchymal state. Sip1 transcripts are expressed in premigratory/migrating crest cells. After Sip1 loss, the neural crest specifier gene FoxD3 was abnormally retained in the dorsal neuroepithelium, whereas Sox10, which is normally required for emigration, was diminished. Subsequently, clumps of adherent neural crest cells remained adjacent to the neural tube and aberrantly expressed E-cadherin while lacking N-cadherin. These findings demonstrate two distinct phases of neural crest EMT, detachment and mesenchymalization, with the latter involving a novel requirement for Sip1 in regulation of cadherin expression during completion of neural crest EMT. PMID:24297751

Rogers, Crystal D.; Saxena, Ankur

2013-01-01

67

RP1 Is a Phosphorylation Target of CK2 and Is Involved in Cell Adhesion  

PubMed Central

RP1 (synonym: MAPRE2, EB2) is a member of the microtubule binding EB1 protein family, which interacts with APC, a key regulatory molecule in the Wnt signalling pathway. While the other EB1 proteins are well characterized the cellular function and regulation of RP1 remain speculative to date. However, recently RP1 has been implicated in pancreatic cancerogenesis. CK2 is a pleiotropic kinase involved in adhesion, proliferation and anti-apoptosis. Overexpression of protein kinase CK2 is a hallmark of many cancers and supports the malignant phenotype of tumor cells. In this study we investigate the interaction of protein kinase CK2 with RP1 and demonstrate that CK2 phosphorylates RP1 at Ser236 in vitro. Stable RP1 expression in cell lines leads to a significant cleavage and down-regulation of N-cadherin and impaired adhesion. Cells expressing a Phospho-mimicking point mutant RP1-ASP236 show a marked decrease of adhesion to endothelial cells under shear stress. Inversely, we found that the cells under shear stress downregulate endogenous RP1, most likely to improve cellular adhesion. Accordingly, when RP1 expression is suppressed by shRNA, cells lacking RP1 display significantly increased cell adherence to surfaces. In summary, RP1 phosphorylation at Ser236 by CK2 seems to play a significant role in cell adhesion and might initiate new insights in the CK2 and EB1 family protein association. PMID:23844040

Göttig, Stephan; Henschler, Reinhard; Markuly, Norbert; Kleber, Sascha; Faust, Michael; Mischo, Axel; Bauer, Stefan; Zweifel, Martin; Knuth, Alexander; Renner, Christoph; Wadle, Andreas

2013-01-01

68

Engineering protein and cell adhesivity using PEO-terminated triblock polymers  

E-print Network

Engineering protein and cell adhesivity using PEO-terminated triblock polymers Valerie A. Liu,1-based tools to control the spatial localization of adhesive proteins and subsequently mammalian cells. Others domains on a variety of biomaterials that deter cell adhesion for up to 4 weeks in culture. The Pluronic

Bhatia, Sangeeta

69

Substrates for Cell Adhesion Prepared via Active Site-Directed Immobilization of a Protein Domain  

E-print Network

Substrates for Cell Adhesion Prepared via Active Site-Directed Immobilization of a Protein Domain matrix. Herein we demonstrate a strategy for controlled, irreversible immobilization of a cell adhesion adhesion. Substrates presenting this protein mediated rapid attachment and spreading of Swiss 3T3

Mrksich, Milan

70

N-cadherin participated in invasion and metastasis of human esophageal squamous cell carcinoma via taking part in the formation of vasculogenic mimicry.  

PubMed

Vasculogenic mimicry (VM) refers to the unique ability of highly aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks, and the presence of VM correlates to an increased risk of metastasis and poor clinical outcome of cancers. Several key molecules, including N-cadherin, have been implicated in VM. However, the role of N-cadherin in the formation of VM in esophageal squamous cell carcinoma (ESCC) had not been elucidated. In this study, firstly we aimed to identify VM patterns in ESCC tissues and to explore their clinical significance. VM was present in 12 out of 56 samples, and ESCC with lymph node metastasis had a higher incidence of VM than that without lymph node metastasis. More importantly, VM channels were associated with the expression of N-cadherin in ESCC tissues. In order to further explore the role of N-cadherin in VM formation and invasion and metastasis in ESCC, secondly, we silenced the expression of N-cadherin with small hairpin RNA in ESCC cell line KYSE-70; herein, we showed that KYSE-70 cells with N-cadherin silencing lost not only the capacity to form tube-like structures on collagen (VM) but also the invasion, metastasis and proliferation ability in KYSE-70 cells in vitro. Taken together, antivascular therapies targeting tumor cell VM may be an effective approach to the treatment of patients with highly metastatic ESCC. PMID:25575439

Wang, Feng; Li, Xiang-Ke; Xu, Hong-Yan; Shan, Zheng-Zheng; Wang, Tao; Yang, Zi-Chang; He, Wei; Wang, Liu-Xing; Fan, Qing-Xia

2015-02-01

71

Evaluation of photodynamic therapy in adhesion protein expression  

PubMed Central

Photodynamic therapy (PDT) is a treatment modality that has clinical applications in both non-neoplastic and neoplastic diseases. PDT involves a light-sensitive compound (photosensitizer), light and molecular oxygen. This procedure may lead to several different cellular responses, including cell death. Alterations in the attachment of cancer cells to the substratum and to each other are important consequences of photodynamic treatment. PDT may lead to changes in the expression of cellular adhesion structure and cytoskeleton integrity, which are key factors in decreasing tumor metastatic potential. HEp-2 cells were photosensitized with aluminum phthalocyanine tetrasulfonate and zinc phthalocyanine, and the proteins ?1-integrin and focal adhesion kinase (FAK) were assayed using fluorescence microscopy. The verification of expression changes in the genes for FAK and ?1 integrin were performed by reverse transcription-polymerase chain reaction (RT-PCR). The results revealed that HEp-2 cells do not express ?-integrin or FAK 12 h following PDT. It was concluded that the PDT reduces the adhesive ability of HEp-2 cells, inhibiting their metastatic potential. The present study aimed to analyze the changes in the expression and organization of cellular adhesion elements and the subsequent metastatic potential of HEp-2 cells following PDT treatment. PMID:25013490

PACHECO-SOARES, CRISTINA; MAFTOU-COSTA, MAIRA; DA CUNHA MENEZES COSTA, CAROLINA GENÚNCIO; DE SIQUEIRA SILVA, ANDREZA CRISTINA; MORAES, KAREN C.M.

2014-01-01

72

Evaluation of photodynamic therapy in adhesion protein expression.  

PubMed

Photodynamic therapy (PDT) is a treatment modality that has clinical applications in both non-neoplastic and neoplastic diseases. PDT involves a light-sensitive compound (photosensitizer), light and molecular oxygen. This procedure may lead to several different cellular responses, including cell death. Alterations in the attachment of cancer cells to the substratum and to each other are important consequences of photodynamic treatment. PDT may lead to changes in the expression of cellular adhesion structure and cytoskeleton integrity, which are key factors in decreasing tumor metastatic potential. HEp-2 cells were photosensitized with aluminum phthalocyanine tetrasulfonate and zinc phthalocyanine, and the proteins ?1-integrin and focal adhesion kinase (FAK) were assayed using fluorescence microscopy. The verification of expression changes in the genes for FAK and ?1 integrin were performed by reverse transcription-polymerase chain reaction (RT-PCR). The results revealed that HEp-2 cells do not express ?-integrin or FAK 12 h following PDT. It was concluded that the PDT reduces the adhesive ability of HEp-2 cells, inhibiting their metastatic potential. The present study aimed to analyze the changes in the expression and organization of cellular adhesion elements and the subsequent metastatic potential of HEp-2 cells following PDT treatment. PMID:25013490

Pacheco-Soares, Cristina; Maftou-Costa, Maira; DA Cunha Menezes Costa, Carolina Genúncio; DE Siqueira Silva, Andreza Cristina; Moraes, Karen C M

2014-08-01

73

Leukocyte adhesion proteins: their role in neutrophil function.  

PubMed Central

In conclusion, the leukocyte proteins of the CD11/18 complex are highly conserved members of the integrin family in mammalian species. They play a key role in phagocytic and adherence mediated activities of neutrophils and appear to be centrally involved in adhesion to endothelial cells as well as transendothelial migration. Their importance in these processes has been documented by the occurrence of the disease now called leukocyte adhesion deficiency and the functional effects of a variety of monoclonal antibodies directed at different epitopes on the heterodimeric glycoprotein chains. These antibodies, as well as those directed at endothelial cell ligands for leukocyte adhesion proteins or peptides which mimic the functional epitopes, offer opportunities to manipulate or modify the inflammatory response in vivo where neutrophil accumulation or action can be harmful. They can also be employed to dissect out the role of PMNs in various repair processes such as wound healing. While bone marrow transplantation can ameliorate the deleterious consequences of severe LAD, continued elucidation of the multiple molecular mechanisms responsible for this disease will pave the way for its future genetic correction. PMID:2577246

Root, R. K.

1990-01-01

74

Proteolysis of the Docking Protein HEF1 and Implications for Focal Adhesion Dynamics  

Microsoft Academic Search

The dynamic regulation of focal adhesions is implicated in cellular processes of proliferation, differentiation, migration, and apoptosis. The focal adhesion-associated docking protein HEF1 is cleaved by caspases during both mitosis and apoptosis. Common to both of these cellular processes is the loss of focal adhesions, transiently during mitosis and permanently during apoptosis. The proteolytic processing of HEF1 during both mitosis

GERALDINE M. O'NEILL; ERICA A. GOLEMIS

2001-01-01

75

Mode of Adsorption and Orientation of an Extracellular Matrix Protein Affect Its Cell-Adhesion-Promoting Activity  

Microsoft Academic Search

Cell adhesion to extracellular matrix contributes to the organization of tissues and modulates cell behavior. In conventional cell adhesion assays, plastic wells are coated with matrix proteins and assayed for their adhesion-promoting activity. We show here that factors such as sample composition, coating buffers, and manufacturers' plastic treatment markedly affect cell adhesion to the extracellular matrix protein laminin-5 (Ln-5). These

Mark I. Fitchmun; Jutta Falk-Marzillier; Eldri Marshall; Gina Cruz; Jonathan C. R. Jones; Vito Quaranta

1998-01-01

76

Boronate Complex Formation with Dopa Containing Mussel Adhesive Protein Retards pH-Induced Oxidation and Enables Adhesion to Mica  

PubMed Central

The biochemistry of mussel adhesion has inspired the design of surface primers, adhesives, coatings and gels for technological applications. These mussel-inspired systems often focus on incorporating the amino acid 3,4-dihydroxyphenyl-L-alanine (Dopa) or a catecholic analog into a polymer. Unfortunately, effective use of Dopa is compromised by its susceptibility to auto-oxidation at neutral pH. Oxidation can lead to loss of adhesive function and undesired covalent cross-linking. Mussel foot protein 5 (Mfp-5), which contains ?30 mole % Dopa, is a superb adhesive under reducing conditions but becomes nonadhesive after pH-induced oxidation. Here we report that the bidentate complexation of borate by Dopa to form a catecholato-boronate can be exploited to retard oxidation. Although exposure of Mfp-5 to neutral pH typically oxidizes Dopa, resulting in a>95% decrease in adhesion, inclusion of borate retards oxidation at the same pH. Remarkably, this Dopa-boronate complex dissociates upon contact with mica to allow for a reversible Dopa-mediated adhesion. The borate protection strategy allows for Dopa redox stability and maintained adhesive function in an otherwise oxidizing environment. PMID:25303409

Israelachvili, Jacob N.; Chen, Yunfei; Waite, J. Herbert

2014-01-01

77

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 PMID:7541610

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

1995-01-01

78

Nucleation and growth of cadherin adhesions  

SciTech Connect

Cell-cell contact formation relies on the recruitment of cadherin molecules and their anchoring to actin. However, the precise chronology of events from initial cadherin trans-interactions to adhesion strengthening is unclear, in part due to the lack of access to the distribution of cadherins within adhesion zones. Using N-cadherin expressing cells interacting with N-cadherin coated surfaces, we characterized the formation of cadherin adhesions at the ventral cell surface. TIRF and RIC microscopies revealed streak-like accumulations of cadherin along actin fibers. FRAP analysis indicated that engaged cadherins display a slow turnover at equilibrium, compatible with a continuous addition and removal of cadherin molecules within the adhesive contact. Association of cadherin cytoplasmic tail to actin as well as actin cables and myosin II activity are required for the formation and maintenance of cadherin adhesions. Using time lapse microscopy we deciphered how cadherin adhesions form and grow. As lamellipodia protrude, cadherin foci stochastically formed a few microns away from the cell margin. Neo-formed foci coalesced aligned and coalesced with preformed foci either by rearward sliding or gap filling to form cadherin adhesions. Foci experienced collapse at the rear of cadherin adhesions. Based on these results, we present a model for the nucleation, directional growth and shrinkage of cadherin adhesions.

Lambert, Mireille [INSERM, U839, Paris, F-75005 (France); Universite Pierre et Marie Curie-Paris6, Paris, Institut du Fer a Moulin, UMR-S0839, Paris, F-75005 (France); Thoumine, Olivier [Universite Bordeaux 2, CNRS, UMR5091, Institut Francois Magendie de Neurosciences, Bordeaux, F-33077 (France); Brevier, Julien [Universite Joseph Fourier, CNRS, UMR5588, Saint-Martin d'Heres, F-38402 (France); Choquet, Daniel [Universite Bordeaux 2, CNRS, UMR5091, Institut Francois Magendie de Neurosciences, Bordeaux, F-33077 (France); Riveline, Daniel [Universite Joseph Fourier, CNRS, UMR5588, Saint-Martin d'Heres, F-38402 (France); Mege, Rene-Marc [INSERM, U839, Paris, F-75005 (France); Universite Pierre et Marie Curie-Paris6, Paris, Institut du Fer a Moulin, UMR-S0839, Paris, F-75005 (France)], E-mail: mege@fer-a-moulin.inserm.fr

2007-11-15

79

A new crystal form of human vascular adhesion protein 1.  

PubMed

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 Rcryst and Rfree values of 0.250 and 0.286, respectively. PMID:21139198

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

2010-12-01

80

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. PMID:21139198

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

81

The glue protein of ribbed mussels ( Geukensia demissa ): a natural adhesive with some features of collagen  

Microsoft Academic Search

The Atlantic ribbed musselGeukensia (Modiolus)demissa attaches itself to the roots of cord grass and other hard objects in tidal salt marshes by spinning adhesive byssal threads. The precursor of a protein apparently present in the adhesive plaques of the threads was isolated in quantity from the foot of the mussel. The protein has an apparent molecular weight of 130000, a

J. Herbert Waite; Douglas C. Hansen; Kathleen T. Little

1989-01-01

82

Cadherin-mediated adhesion regulates posterior body formation  

PubMed Central

Background The anterior-posterior axis of the vertebrate embryo undergoes a dramatic elongation during early development. Convergence and extension of the mesoderm, occurring during gastrulation, initiates the narrowing and lengthening of the embryo. However the lengthening of the axis continues during post-gastrula stages in the tailbud region, and is thought to involve convergent extension movements as well as other cell behaviors specific to posterior regions. Results We demonstrate here, using a semi-dominant N-cadherin allele, that members of the classical cadherin subfamily of cell-cell adhesion molecules are required for tailbud elongation in the zebrafish. In vivo imaging of cell behaviors suggests that the extension of posterior axial mesodermal cells is impaired in embryos that carry the semi-dominant N-cadherin allele. This defect most likely results from a general loss of cell-cell adhesion in the tailbud region. Consistent with these observations, N-cadherin is expressed throughout the tailbud during post-gastrulation stages. In addition, we show that N-cadherin interacts synergistically with vang-like 2, a member of the non-canonical Wnt signaling/planar cell polarity pathway, to mediate tail morphogenesis. Conclusion We provide the first evidence here that N-cadherin and other members of the classical cadherin subfamily function in parallel with the planar cell polarity pathway to shape the posterior axis during post-gastrulation stages. These findings further highlight the central role that adhesion molecules play in the cellular rearrangements that drive morphogenesis in vertebrates and identify classical cadherins as major contributors to tail development. PMID:18045497

Harrington, Michael J; Hong, Elim; Fasanmi, Oluwafoyinsa; Brewster, Rachel

2007-01-01

83

Adhesion G-Protein Coupled Receptors: Elusive Hybrids Come of Age  

PubMed Central

Adhesion G-protein coupled receptors (GPCRs) are the most recently identified and least understood subfamily of GPCRs. Adhesion GPCRs are characterized by unusually long ectodomains with adhesion-related repeats that facilitate cell-cell and cell-cell matrix contact, as well as a proteolytic cleavage site-containing domain that is a structural hallmark of the family. Their unusual chimeric structure of adhesion-related ectodomain with a seven-pass transmembrane domain and cytoplasmic signaling makes these proteins highly versatile in mediating cellular signaling in response to extracellular adhesion or cell motility events. The ligand binding and cytoplasmic signaling modes for members of this family are beginning to be elucidated, and recent studies have demonstrated critical roles for Adhesion GPCRs in planar polarity and other important cell-cell and cell-matrix interactions during development and morphogenesis, as well as heritable diseases and cancer. PMID:24229322

Simundza, Julia; Cowin, Pamela

2014-01-01

84

Symmetric exchange of multi-protein building blocks between stationary focal adhesions and the cytosol  

PubMed Central

How can the integrin adhesome get self-assembled locally, rapidly, and correctly as diverse cell-matrix adhesion sites? Here, we investigate this question by exploring the cytosolic state of integrin-adhesome components and their dynamic exchange between adhesion sites and cytosol. Using fluorescence cross-correlation spectroscopy (FCCS) and fluorescence recovery after photobleaching (FRAP) we found that the integrin adhesome is extensively pre-assembled already in the cytosol as multi-protein building blocks for adhesion sites. Stationary focal adhesions release symmetrically the same types of protein complexes that they recruit, thereby keeping the cytosolic pool of building blocks spatiotemporally uniform. We conclude a model in which multi-protein building blocks enable rapid and modular self-assembly of adhesion sites and symmetric exchange of these building blocks preserves their specifications and thus the assembly logic of the system. DOI: http://dx.doi.org/10.7554/eLife.02257.001 PMID:24894463

Hoffmann, Jan-Erik; Fermin, Yessica; Stricker, Ruth LO; Ickstadt, Katja; Zamir, Eli

2014-01-01

85

p38 mitogen-activated protein kinase interacts with vinculin at focal adhesions during fatty acid-stimulated cell adhesion  

PubMed Central

Arachidonic acid stimulates cell adhesion by activating ?2?1 integrins in a process that depends on protein kinases, including p38 mitogen activated protein kinase. Here, we describe the interaction of cytoskeletal components with key signaling molecules that contribute to spreading of, and morphological changes in, arachidonic acid-treated MDA-MB-435 human breast carcinoma cells. Arachidonic acid-treated cells showed increased attachment and spreading on collagen type IV as measured by electric cell-substrate impedance sensing. Fatty acid-treated cells displayed short cortical actin filaments associated with an increased number of ?1 integrin-containing pseudopodia whereas untreated cells displayed elongated stress fibers and fewer clusters of ?1 integrins. Confocal microscopy of arachidonic acid-treated cells showed that vinculin and phospho-p38 both appeared enriched in pseudopodia and at the tips of actin filaments, and fluorescence ratio imaging indicated the increase was specific for the phospho-(active) form of p38. Immunoprecipitates of phospho-p38 from extracts of arachidonic acid-treated cells contained vinculin, and GST-vinculin fusion proteins carrying the central region of vinculin bound phospho-p38, whereas fusion proteins expressing the terminal portions of vinculin did not. These data suggest that phospho-p38 associates with particular domains on critical focal adhesion proteins that are involved in tumor cell adhesion and spreading and that this association can be regulated by factors in the tumor microenvironment. PMID:24219282

George, Margaret D.; Wine, Robert N.; Lackford, Brad; Kissling, Grace E.; Akiyama, Steven K.; Olden, Kenneth; Roberts, John D.

2014-01-01

86

Protein Recovery from Secondary Paper Sludge and Its Potential Use as Wood Adhesive  

NASA Astrophysics Data System (ADS)

Secondary sludge is an essential part of biosolids produced through the waste treatment plant of paper mills. Globally paper mills generate around 3.0 million ton of biosolids and in the absence of beneficial applications, the handling and disposal of this residual biomass poses a serious environmental and economic proposition. Secondary paper sludges were investigated in this work for recovery of proteins and their use as wood adhesive. After identifying extracellular polymeric substances as adhesion pre-cursors through analytical techniques, studies were carried out to optimize protein recovery from SS and its comprehensive characterization. A modified physicochemical protocol was developed to recover protein from secondary sludge in substantial quantities. The combined effect of French press and sonication techniques followed by alkali treatment resulted in significant improvement of 44% in the yield of solubilized protein compared to chemical methods. The characterization studies confirmed the presence of common amino acids in recovered sludge protein in significant quantities and heavy metal concentration was reduced after recovery process. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed the presence of both low and high molecular weight protein fractions in recovered sludge protein. After establishing the proof-of-concept in the use of recovered sludge protein as wood adhesive, the bonding mechanism of protein adhesives with cellulose substrate was further elucidated in a complementary protein-modification study involving soy protein isolate and its glycinin fractions. The results of this study validated the prevailing bonding theories by proving that surface wetting, protein structure, and type of wood play important role in determining final adhesive strength. Recovered sludge protein was also investigated for its compatibility to formulate hybrid adhesive blends with formaldehyde and bio-based polymers. Apart from chemical cross-linking, the synergy of adhesive blends was evaluated through classical rule-of-mixture. The findings of this study warrants further investigation concerning other potential uses of recovered sludge protein, especially as food supplements and economic implications.

Pervaiz, Muhammad

87

Experimental strategies for the identification and characterization of adhesive proteins in animals: a review.  

PubMed

Adhesive secretions occur in both aquatic and terrestrial animals, in which they perform diverse functions. Biological adhesives can therefore be remarkably complex and involve a large range of components with different functions and interactions. However, being mainly protein based, biological adhesives can be characterized by classical molecular methods. This review compiles experimental strategies that were successfully used to identify, characterize and obtain the full-length sequence of adhesive proteins from nine biological models: echinoderms, barnacles, tubeworms, mussels, sticklebacks, slugs, velvet worms, spiders and ticks. A brief description and practical examples are given for a variety of tools used to study adhesive molecules at different levels from genes to secreted proteins. In most studies, proteins, extracted from secreted materials or from adhesive organs, are analysed for the presence of post-translational modifications and submitted to peptide sequencing. The peptide sequences are then used directly for a BLAST search in genomic or transcriptomic databases, or to design degenerate primers to perform RT-PCR, both allowing the recovery of the sequence of the cDNA coding for the investigated protein. These sequences can then be used for functional validation and recombinant production. In recent years, the dual proteomic and transcriptomic approach has emerged as the best way leading to the identification of novel adhesive proteins and retrieval of their complete sequences. PMID:25657842

Hennebert, Elise; Maldonado, Barbara; Ladurner, Peter; Flammang, Patrick; Santos, Romana

2015-02-01

88

Experimental strategies for the identification and characterization of adhesive proteins in animals: a review  

PubMed Central

Adhesive secretions occur in both aquatic and terrestrial animals, in which they perform diverse functions. Biological adhesives can therefore be remarkably complex and involve a large range of components with different functions and interactions. However, being mainly protein based, biological adhesives can be characterized by classical molecular methods. This review compiles experimental strategies that were successfully used to identify, characterize and obtain the full-length sequence of adhesive proteins from nine biological models: echinoderms, barnacles, tubeworms, mussels, sticklebacks, slugs, velvet worms, spiders and ticks. A brief description and practical examples are given for a variety of tools used to study adhesive molecules at different levels from genes to secreted proteins. In most studies, proteins, extracted from secreted materials or from adhesive organs, are analysed for the presence of post-translational modifications and submitted to peptide sequencing. The peptide sequences are then used directly for a BLAST search in genomic or transcriptomic databases, or to design degenerate primers to perform RT-PCR, both allowing the recovery of the sequence of the cDNA coding for the investigated protein. These sequences can then be used for functional validation and recombinant production. In recent years, the dual proteomic and transcriptomic approach has emerged as the best way leading to the identification of novel adhesive proteins and retrieval of their complete sequences. PMID:25657842

Hennebert, Elise; Maldonado, Barbara; Ladurner, Peter; Flammang, Patrick; Santos, Romana

2015-01-01

89

Cell Adhesion to Unnatural Ligands Mediated by a Bifunctional Protein  

E-print Network

do not present ligands that can mediate adhesion. The approach is based on a carbonic anhydrase). To restore adhesion to this monolayer, we designed and expressed a human carbonic anhydrase IV (h carbonic anhydrase binds to benzenesulfonamide ligand with micromolar affinity,8 we (1) Servoli, E

Mrksich, Milan

90

The effect of moonlighting proteins on the adhesion and aggregation ability of Lactobacillus helveticus.  

PubMed

The goal of this study was to identify moonlighting proteins in Lactobacillus helveticus that play an important role in adhesion and aggregation. The label-free method was used for identification and analysis of expression of cellular proteins. The analysis revealed the presence of eight moonlighting proteins in the cell envelope of Lb. helveticus. The tested strains mainly differed with respect to the presence of S-layer proteins and the level of expression of moonlighting proteins in Lb. helveticus strain T159. These surface proteins give the cell a hydrophobic character and play a role in specific interactions with intestinal epithelium cells and with other bacteria. In Lb. helveticus T159, the S-layer associated with moonlighting proteins could act as adherence factors, which was evidenced by the high capability of adhesion, auto- and coaggregation. The hydrophobicity, adhesion and aggregation abilities provide biological activities in food products and they are regarded as an important criterion for probiotic selection. PMID:25445202

Wa?ko, Adam; Polak-Berecka, Magdalena; Paduch, Roman; Jó?wiak, Krzysztof

2014-10-13

91

Redundant control of migration and adhesion by ERM proteins in vascular smooth muscle cells  

SciTech Connect

Highlights: •The three ERM proteins are expressed in vascular smooth muscle cell. •ERM depletion inhibited PDGF-evoked migration redundantly. •ERM depletion increased cell adhesion redundantly. •ERM depletion did not affect PDGF-evoked Ca signal, Rac1 activation, proliferation. •ERM proteins control PDGF-induced migration by regulating adhesion. -- Abstract: Ezrin, radixin, and moesin possess a very similar structure with a C-terminal actin-binding domain and a N-terminal FERM interacting domain. They are known to be involved in cytoskeleton organization in several cell types but their function in vascular smooth muscle cells (VSMC) is still unknown. The aim of this study was to investigate the role of ERM proteins in cell migration induced by PDGF, a growth factor involved in pathophysiological processes like angiogenesis or atherosclerosis. We used primary cultured VSMC obtained from rat aorta, which express the three ERM proteins. Simultaneous depletion of the three ERM proteins with specific siRNAs abolished the effects of PDGF on cell architecture and migration and markedly increased cell adhesion and focal adhesion size, while these parameters were only slightly affected by depletion of ezrin, radixin or moesin alone. Rac1 activation, cell proliferation, and Ca{sup 2+} signal in response to PDGF were unaffected by ERM depletion. These results indicate that ERM proteins exert a redundant control on PDGF-induced VSMC migration by regulating focal adhesion turn-over and cell adhesion to substrate.

Baeyens, Nicolas; Latrache, Iman; Yerna, Xavier [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium)] [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium); Noppe, Gauthier; Horman, Sandrine [Pôle de Recherche Cardiovasculaire, IREC, Université Catholique de Louvain (Belgium)] [Pôle de Recherche Cardiovasculaire, IREC, Université Catholique de Louvain (Belgium); Morel, Nicole, E-mail: nicole.morel@uclouvain.be [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium)] [Laboratory of Cell Physiology, IoNS, Université Catholique de Louvain (Belgium)

2013-11-22

92

Fast Turnover of L1 Adhesions in Neuronal Growth Cones Involving Both Surface Diffusion and Exo/Endocytosis of L1 Molecules  

PubMed Central

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

2007-01-01

93

Specific proteins mediate enhanced osteoblast adhesion on nanophase ceramics.  

PubMed

Osteoblast, fibroblast, and endothelial cell adhesion on nanophase (that is, materials with grain sizes less than 100 nm) alumina, titania, and hydroxyapatite (HA) was investigated using in vitro cellular models. Osteoblast adhesion was significantly (p < 0.01) greater after 4 h on nanophase alumina, titania, and HA than it was on conventional formulations of the same ceramics. In contrast, compared to conventional alumina, titania, and HA, after 4 h fibroblast adhesion was significantly (p < 0.01) less on nanophase ceramics. Examination of the underlying mechanism(s) of cell adhesion on nanophase ceramics revealed that these ceramics adsorbed significantly (p < 0.01) greater quantities of vitronectin, which, subsequently, may have contributed to the observed select enhanced adhesion of osteoblasts. Select enhanced osteoblast adhesion was independent of surface chemistry and material phase but was dependent on the surface topography (specifically on grain and pore size) of nanophase ceramics. The capability of synthesizing and processing nanomaterials with tailored (through, for example, specific grain and pore size) structures and topographies to control select subsequent cell functions provides the possibility of designing the novel proactive biomaterials (that is, materials that elicit specific, timely, and desirable responses from surrounding cells and tissues) necessary for improved implant efficacy. PMID:10880091

Webster, T J; Ergun, C; Doremus, R H; Siegel, R W; Bizios, R

2000-09-01

94

Strong underwater adhesives made by self-assembling multi-protein nanofibres.  

PubMed

Many natural underwater adhesives harness hierarchically assembled amyloid nanostructures to achieve strong and robust interfacial adhesion under dynamic and turbulent environments. Despite recent advances, our understanding of the molecular design, self-assembly and structure-function relationships of these natural amyloid fibres remains limited. Thus, designing biomimetic amyloid-based adhesives remains challenging. Here, we report strong and multi-functional underwater adhesives obtained from fusing mussel foot proteins (Mfps) of Mytilus galloprovincialis with CsgA proteins, the major subunit of Escherichia coli amyloid curli fibres. These hybrid molecular materials hierarchically self-assemble into higher-order structures, in which, according to molecular dynamics simulations, disordered adhesive Mfp domains are exposed on the exterior of amyloid cores formed by CsgA. Our fibres have an underwater adhesion energy approaching 20.9?mJ?m(-2), which is 1.5 times greater than the maximum of bio-inspired and bio-derived protein-based underwater adhesives reported thus far. Moreover, they outperform Mfps or curli fibres taken on their own and exhibit better tolerance to auto-oxidation than Mfps at pH???7.0. PMID:25240674

Zhong, Chao; Gurry, Thomas; Cheng, Allen A; Downey, Jordan; Deng, Zhengtao; Stultz, Collin M; Lu, Timothy K

2014-10-01

95

Adhesive proteins of stalked and acorn barnacles display homology with low sequence similarities.  

PubMed

Barnacle adhesion underwater is an important phenomenon to understand for the prevention of biofouling and potential biotechnological innovations, yet so far, identifying what makes barnacle glue proteins 'sticky' has proved elusive. Examination of a broad range of species within the barnacles may be instructive to identify conserved adhesive domains. We add to extensive information from the acorn barnacles (order Sessilia) by providing the first protein analysis of a stalked barnacle adhesive, Lepas anatifera (order Lepadiformes). It was possible to separate the L. anatifera adhesive into at least 10 protein bands using SDS-PAGE. Intense bands were present at approximately 30, 70, 90 and 110 kilodaltons (kDa). Mass spectrometry for protein identification was followed by de novo sequencing which detected 52 peptides of 7-16 amino acids in length. None of the peptides matched published or unpublished transcriptome sequences, but some amino acid sequence similarity was apparent between L. anatifera and closely-related Dosima fascicularis. Antibodies against two acorn barnacle proteins (ab-cp-52k and ab-cp-68k) showed cross-reactivity in the adhesive glands of L. anatifera. We also analysed the similarity of adhesive proteins across several barnacle taxa, including Pollicipes pollicipes (a stalked barnacle in the order Scalpelliformes). Sequence alignment of published expressed sequence tags clearly indicated that P. pollicipes possesses homologues for the 19 kDa and 100 kDa proteins in acorn barnacles. Homology aside, sequence similarity in amino acid and gene sequences tended to decline as taxonomic distance increased, with minimum similarities of 18-26%, depending on the gene. The results indicate that some adhesive proteins (e.g. 100 kDa) are more conserved within barnacles than others (20 kDa). PMID:25295513

Jonker, Jaimie-Leigh; Abram, Florence; Pires, Elisabete; Varela Coelho, Ana; Grunwald, Ingo; Power, Anne Marie

2014-01-01

96

Identification of an Invasive, N-Cadherin-Expressing Epithelial Cell Type in Endometriosis Using a New Cell Culture Model  

PubMed Central

Studies of molecular, cellular, and pathophysiological parameters in endometriosis are primarily hampered by a lack of in vitro model systems, such as endometriotic cell lines. To overcome this we successfully established cell lines from peritoneal endometriotic biopsies and characterized them at the molecular and cellular level. Two types of cells could be transformed: one exhibiting stromal cell features (cytokeratin/E-cadherin-negative), the other epithelial-like (cytokeratin-positive/E-cadherin-negative, invasive in vitro). Using a Matrigel assay the epithelial-like cell lines proved as invasive as metastatic carcinoma cells, possibly through the influence of N-cadherin implicated as a path-finding cadherin allowing cellular invasion and migration in both normal and pathophysiological processes. Our results support the idea that endometriosis, although not neoplastic, shares features with malignant cells and that metastasis in endometriosis may include mechanisms proposed for micrometastasis in cancer. Thus our cell lines will not only be useful tools for analyzing molecular and cellular events relating to endometriosis, but may also represent a paradigm for invasion and metastasis in general. PMID:11696444

Zeitvogel, Andreas; Baumann, Rudolf; Starzinski-Powitz, Anna

2001-01-01

97

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

PubMed

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 X chromosome inactivation, androgenized female rats heterozygous for the tfm androgen receptor mutation (X(WT)X(tfm)) are phenotypic mosaics of androgen-sensitive wild-type (WT) and androgen-insensitive (tfm) motoneurons. We compared steroid effects on WT and tfm cells in two sexually-dimorphic motoneuron pools, the spinal nucleus of the bulbocavernosus (SNB) and the dorsolateral nucleus (DLN), as well as a less steroid responsive motoneuron pool, the sexually monomorphic retrodorsolateral nucleus (RDLN). Independent of steroid treatment, a greater proportion of wild-type cells were N-cad immunoreactive (IR) in the DLN and RDLN. Following testosterone treatment, increased N-cad expression was observed in both cell types in the DLN, but in the SNB only the androgen-competent WT cells increased N-cad expression. Testosterone treatment did not significantly alter N-cad expression in the mosaic RDLN. The results indicate both cell autonomous and cell non-autonomous androgenic regulation of N-cad expression in spinal motoneurons. PMID:11259762

Monks, D A; Watson, N V

2001-03-23

98

Synergistic roles for lipids and proteins in the permanent adhesive of barnacle larvae.  

PubMed

Thoracian barnacles rely heavily upon their ability to adhere to surfaces and are environmentally and economically important as biofouling pests. Their adhesives have unique attributes that define them as targets for bio-inspired adhesive development. With the aid of multi-photon and broadband coherent anti-Stokes Raman scattering microscopies, we report that the larval adhesive of barnacle cyprids is a bi-phasic system containing lipids and phosphoproteins, working synergistically to maximize adhesion to diverse surfaces under hostile conditions. Lipids, secreted first, possibly displace water from the surface interface creating a conducive environment for introduction of phosphoproteins while simultaneously modulating the spreading of the protein phase and protecting the nascent adhesive plaque from bacterial biodegradation. The two distinct phases are contained within two different granules in the cyprid cement glands, implying far greater complexity than previously recognized. Knowledge of the lipidic contribution will hopefully inspire development of novel synthetic bioadhesives and environmentally benign antifouling coatings. PMID:25014570

Gohad, Neeraj V; Aldred, Nick; Hartshorn, Christopher M; Jong Lee, Young; Cicerone, Marcus T; Orihuela, Beatriz; Clare, Anthony S; Rittschof, Dan; Mount, Andrew S

2014-01-01

99

E-cadherin and ?-catenin adhesion proteins correlate positively with connexins in colorectal cancer.  

PubMed

The majority of solid cancers present with qualitative and quantitative aberrations of adhesion proteins, including E-cadherin and ?-catenin, and connexin (Cx) gap junction proteins, which is consistent with alterations in the expression and location of such proteins in neoplastic cells. Since there are no data on the correlation between adhesion proteins and Cxs in human colorectal cancer (CRC), the aim of the present study was to evaluate the expression and correlation between these proteins. Tissue specimens were obtained from 151 cases of surgically removed colorectal adenocarcinomas. The samples were examined by immunohistochemistry with the use of antibodies against E-cadherin, ?-catenin and the three Cxs: Cx26, Cx32 and Cx43. The aberrant expression of the studied adhesion proteins (primarily cytoplasmic for E-cadherin and cytoplasmic and/or nuclear for ?-catenin) was observed, whereas only a minority of cases revealed normal membranous distribution of the labeling. The present study is the first in the literature to reveal a correlation between the expression of E-cadherin and ?-catenin and the examined Cxs in CRC in humans. The positive correlation between the Cxs, particularly Cx26 and Cx32, and the adhesive proteins occurred in patients without lymph node metastases and in the moderately differentiated tumors (G2). Such a dependency was not observed in the analysis of the correlation between Cx43 and E-cadherin. However, a positive correlation between these proteins was observed in patients with lymph nodes metastases. Additionally, a link between the expression of these adhesion proteins was observed. The present study indicates, for the first time, that the expression of adhesion proteins, E-cadherin and ?-catenin, is closely associated with the expression of three studied Cxs in CRC, and that this correlation may improve an understanding of the carcinogenic process in this cancer. PMID:24932249

Kanczuga-Koda, Luiza; Wincewicz, Andrzej; Fudala, Andrzej; Abrycki, Tomasz; Famulski, Waldemar; Baltaziak, Marek; Sulkowski, Stanislaw; Koda, Mariusz

2014-06-01

100

Diatom Adhesive Mucilage Contains Distinct Supramolecular Assemblies of a Single Modular Protein  

PubMed Central

A previous study used atomic force microscopy saw-tooth retraction curves to characterize the adhesive mucilage pads of the diatom Toxarium undulatum. The major mucilage component consisted of adhesive nanofibers (ANFs) made up of modular proteins arranged into cohesive units, each containing a set number of modular proteins aligned in parallel. This study shows that T. undulatum adhesive mucilage is a biocomposite containing four additional adhesive components, including single modular proteins that are likely to be the structural units from which the ANFs are assembled. Two further distinct supramolecular assemblies were observed to coexist with ANFs (ANFs II and III), along with a continuum of single modular proteins through oligomers made up of varying numbers of modular proteins arranged in parallel. All components of the adhesive biocomposite produce a characteristic force spectrum with the same interpeak distance (35.3 ± 0.3 (mean ± SE) nm), suggesting they are derived from discrete supramolecular assemblies of the same modular protein, but they are distinguishable from one another based on the rupture force, persistence length, and interpeak force measured from their saw-tooth curves. PMID:16443662

Dugdale, T. M.; Dagastine, R.; Chiovitti, A.; Wetherbee, R.

2006-01-01

101

Structural basis of cell-cell adhesion by cadherins.  

PubMed

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 cell-adhesion zipper may provide a mechanism to marshal individual molecular adhesive interactions into strong bonds between cells. PMID:7885471

Shapiro, L; Fannon, A M; Kwong, P D; Thompson, A; Lehmann, M S; Grübel, G; Legrand, J F; Als-Nielsen, J; Colman, D R; Hendrickson, W A

1995-03-23

102

c-Yes regulates cell adhesion at the blood-testis barrier and the apical ectoplasmic specialization in the seminiferous epithelium of rat testes.  

PubMed

During spermatogenesis, extensive junction restructuring takes place at the blood-testis barrier (BTB) and the Sertoli cell-spermatid interface known as the apical ectoplasmic specialization (apical ES, a testis-specific adherens junction) in the seminiferous epithelium. However, the mechanism(s) that regulates these critical events in the testis remains unknown. Based on the current concept in the field, changes in the phosphorylation status of integral membrane proteins at these sites can induce alterations in protein endocytosis and recycling, causing junction restructuring. Herein, c-Yes, a non-receptor protein tyrosine kinase, was found to express abundantly at the BTB and apical ES stage-specifically, coinciding with junction restructuring events at these sites during the seminiferous epithelial cycle of spermatogenesis. c-Yes also structurally associated with adhesion proteins at the BTB (e.g., occludin and N-cadherin) and the apical ES (e.g., ?1-integrin, laminins ?3 and ?3), possibly to regulate phosphorylation status of proteins at these sites. SU6656, a selective c-Yes inhibitor, was shown to perturb the Sertoli cell tight junction-permeability barrier in vitro, which is mediated by changes in the distribution of occludin and N-cadherin at the cell-cell interface, moving from cell surface to cytosol, thereby destabilizing the tight junction-barrier. However, this disruptive effect of SU6656 on the barrier was blocked by testosterone. Furthermore, c-Yes is crucial to maintain the actin filament network in Sertoli cells since a blockade of c-Yes by SU6656 induced actin filament disorganization. In summary, c-Yes regulates BTB and apical ES integrity by maintaining proper distribution of integral membrane proteins and actin filament organization at these sites. PMID:21256972

Xiao, Xiang; Mruk, Dolores D; Lee, Will M; Cheng, C Yan

2011-04-01

103

Mussel Adhesive Protein Mimetic Polymers for the Preparation of Nonfouling Surfaces  

E-print Network

of a protein found in Mytilus edulis adhesive plaques. Gold and titanium surfaces were modified by adsorption be broadly applied to medical implants and diagnostics, as well as numerous nonmedical applications in which a biocompatible polymer which when immobilized onto surfaces confers protein and cell resistance.2 Existing

104

Binding of the WASP/N-WASP-Interacting Protein WIP to Actin Regulates Focal Adhesion Assembly and Adhesion  

PubMed Central

The actin cytoskeleton is essential for cell adhesion and migration, functions important for tumor invasion. In addition to binding N-WASP/WASP, WIP binds and stabilizes F-actin. WIP?/? fibroblasts were used to test the role of WIP in F-actin function. WIP?/? cells had defective focal adhesion (FA), stress fiber assembly, and adherence to substrates, functions that were restored by transduction of wild-type WIP. Protein and mRNA levels of several FA constituents regulated by the myocardin-related transcription factor (MRTF)–serum response factor (SRF) transcription factor complex were reduced in WIP?/? fibroblasts. The level of G-actin, which sequesters MRTF in the cytoplasm, was increased, and nuclear localization of MRTF-A and SRF was reduced, in WIP?/? fibroblasts. Transfection of an MRTF-A mutant that constitutively translocates to the nucleus or transfection of constitutively active SRF restored FA and stress fiber assembly. Fibroblasts from knock-in mice expressing a WIP mutant that fails to bind actin phenocopied WIP?/? fibroblasts. Thus, WIP is a novel regulator of FA assembly and cell adhesion. PMID:24797074

Massaad, Michel J.; Kumar, Lalit; Koduru, Suresh; Sasahara, Yoji; Anton, Ines; Bhasin, Manoj; Libermann, Towia

2014-01-01

105

Adhesion properties of Lactobacillus rhamnosus mucus-binding factor to mucin and extracellular matrix proteins.  

PubMed

We previously described potential probiotic Lactobacillus rhamnosus strains, isolated from fermented mare milk produced in Sumbawa Island, Indonesia, which showed high adhesion to porcine colonic mucin (PCM) and extracellular matrix (ECM) proteins. Recently, mucus-binding factor (MBF) was found in the GG strain of L. rhamnosus as a mucin-binding protein. In this study, we assessed the ability of recombinant MBF protein from the FSMM22 strain, one of the isolates of L. rhamnosus from fermented Sumbawa mare milk, to adhere to PCM and ECM proteins by overlay dot blot and Biacore assays. MBF bound to PCM, laminin, collagen IV, and fibronectin with submicromolar dissociation constants. Adhesion of the FSMM22 mbf mutant strain to PCM and ECM proteins was significantly less than that of the wild-type strain. Collectively, these results suggested that MBF contribute to L. rhamnosus host colonization via mucin and ECM protein binding. PMID:25351253

Nishiyama, Keita; Nakamata, Koichi; Ueno, Shintaro; Terao, Akari; Aryantini, Ni Putu Desy; Sujaya, I Nengah; Fukuda, Kenji; Urashima, Tadasu; Yamamoto, Yuji; Mukai, Takao

2014-10-29

106

Secreted Frizzled-related protein 1 (sFRP1) regulates spermatid adhesion in the testis via dephosphorylation of focal adhesion kinase and the nectin-3 adhesion protein complex  

PubMed Central

Development of spermatozoa in adult mammalian testis during spermatogenesis involves extensive cell migration and differentiation. Spermatogonia that reside at the basal compartment of the seminiferous epithelium differentiate into more advanced germ cell types that migrate toward the apical compartment until elongated spermatids are released into the tubule lumen during spermiation. Apical ectoplasmic specialization (ES; a testis-specific anchoring junction) is the only cell junction that anchors and maintains the polarity of elongating/elongated spermatids (step 8–19 spermatids) in the epithelium. Little is known regarding the signaling pathways that trigger the disassembly of the apical ES at spermiation. Here, we show that secreted Frizzled-related protein 1 (sFRP1), a putative tumor suppressor gene that is frequently down-regulated in multiple carcinomas, is a crucial regulatory protein for spermiation. The expression of sFRP1 is tightly regulated in adult rat testis to control spermatid adhesion and sperm release at spermiation. Down-regulation of sFRP1 during testicular development was found to coincide with the onset of the first wave of spermiation at approximately age 45 d postpartum, implying that sFRP1 might be correlated with elongated spermatid adhesion conferred by the apical ES before spermiation. Indeed, administration of sFRP1 recombinant protein to the testis in vivo delayed spermiation, which was accompanied by down-regulation of phosphorylated (p)-focal adhesion kinase (FAK)-Tyr397 and retention of nectin-3 adhesion protein at the apical ES. To further investigate the functional relationship between p-FAK-Tyr397 and localization of nectin-3, we overexpressed sFRP1 using lentiviral vectors in the Sertoli-germ cell coculture system. Consistent with the in vivo findings, overexpression of sFRP1 induced down-regulation of p-FAK-Tyr397, leading to a decline in phosphorylation of nectin-3. In summary, this report highlights the critical role of sFRP1 in regulating spermiation via its effects on the FAK signaling and retention of nectin-3 adhesion complex at the apical ES.—Wong, E. W. P., Lee, W. M., Cheng, C. Y. Secreted Frizzled-related protein 1 (sFRP1) regulates spermatid adhesion in the testis via dephosphorylation of focal adhesion kinase and the nectin-3 adhesion protein complex. PMID:23073828

Wong, Elissa W. P.; Lee, Will M.; Cheng, C. Yan

2013-01-01

107

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

108

Corneal Cell Adhesion to Contact Lens Hydrogel Materials Enhanced via Tear Film Protein Deposition  

PubMed Central

Tear film protein deposition on contact lens hydrogels has been well characterized from the perspective of bacterial adhesion and viability. However, the effect of protein deposition on lens interactions with the corneal epithelium remains largely unexplored. The current study employs a live cell rheometer to quantify human corneal epithelial cell adhesion to soft contact lenses fouled with the tear film protein lysozyme. PureVision balafilcon A and AirOptix lotrafilcon B lenses were soaked for five days in either phosphate buffered saline (PBS), borate buffered saline (BBS), or Sensitive Eyes Plus Saline Solution (Sensitive Eyes), either pure or in the presence of lysozyme. Treated contact lenses were then contacted to a live monolayer of corneal epithelial cells for two hours, after which the contact lens was sheared laterally. The apparent cell monolayer relaxation modulus was then used to quantify the extent of cell adhesion to the contact lens surface. For both lens types, lysozyme increased corneal cell adhesion to the contact lens, with the apparent cell monolayer relaxation modulus increasing up to an order of magnitude in the presence of protein. The magnitude of this increase depended on the identity of the soaking solution: lenses soaked in borate-buffered solutions (BBS, Sensitive Eyes) exhibited a much greater increase in cell attachment upon protein addition than those soaked in PBS. Significantly, all measurements were conducted while subjecting the cells to moderate surface pressures and shear rates, similar to those experienced by corneal cells in vivo. PMID:25144576

Elkins, Claire M.; Qi, Qin M.; Fuller, Gerald G.

2014-01-01

109

Corneal cell adhesion to contact lens hydrogel materials enhanced via tear film protein deposition.  

PubMed

Tear film protein deposition on contact lens hydrogels has been well characterized from the perspective of bacterial adhesion and viability. However, the effect of protein deposition on lens interactions with the corneal epithelium remains largely unexplored. The current study employs a live cell rheometer to quantify human corneal epithelial cell adhesion to soft contact lenses fouled with the tear film protein lysozyme. PureVision balafilcon A and AirOptix lotrafilcon B lenses were soaked for five days in either phosphate buffered saline (PBS), borate buffered saline (BBS), or Sensitive Eyes Plus Saline Solution (Sensitive Eyes), either pure or in the presence of lysozyme. Treated contact lenses were then contacted to a live monolayer of corneal epithelial cells for two hours, after which the contact lens was sheared laterally. The apparent cell monolayer relaxation modulus was then used to quantify the extent of cell adhesion to the contact lens surface. For both lens types, lysozyme increased corneal cell adhesion to the contact lens, with the apparent cell monolayer relaxation modulus increasing up to an order of magnitude in the presence of protein. The magnitude of this increase depended on the identity of the soaking solution: lenses soaked in borate-buffered solutions (BBS, Sensitive Eyes) exhibited a much greater increase in cell attachment upon protein addition than those soaked in PBS. Significantly, all measurements were conducted while subjecting the cells to moderate surface pressures and shear rates, similar to those experienced by corneal cells in vivo. PMID:25144576

Elkins, Claire M; Qi, Qin M; Fuller, Gerald G

2014-01-01

110

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

2013-08-01

111

Topography-induced cell adhesion to Acr-sP(EO-stat-PO) hydrogels: the role of protein adsorption.  

PubMed

Topographic surface patterning of intrinsically non-adhesive P(EO-stat-PO)-based hydrogels can lead to the adhesion and spreading of fibroblasts. Explanations for this unexpected behavior are discussed, particularly with regard to non-specific protein adsorption from the serum-supplemented culture medium. The presence of serum proteins is shown to be essential for adhesion. Adsorption of plasma and ECM proteins (Fibronectin (FN) and Vitronectin (VN)) to the hydrogels is possible. The effect of VN on initial cell adhesion is analyzed in detail. It appears that VN is the main serum component that is crucial for initial cell adhesion to PEG and that surface topography is essential for further, durable adhesion establishment, and spreading. PMID:21786421

Schulte, Vera A; Diez, Mar; Möller, Martin; Lensen, Marga C

2011-10-10

112

Isolation of an adhesion-mediating protein from chick neural retina adherons  

PubMed Central

Adherons are high molecular weight glycoprotein complexes which are released into the growth medium of cultured cells. They mediate the adhesive interactions of many cell types, including those of embryonic chick neural retina. The cell surface receptor for chick neural retina adherons has been purified, and shown to be a heparan sulfate proteoglycan (Schubert, D., and M. LaCorbiere, 1985, J. Cell Biol., 100:56-63). This paper describes the isolation and characterization of a protein in neural retina adherons which interacts specifically with the cell surface receptor. The 20,000-mol-wt protein, called retinal purpurin (RP), stimulates neural retina cell-substratum adhesion and prolongs the survival of neural retina cells in culture. The RP protein interacts with heparin and heparan sulfate, but not with other glycosaminoglycans. Monovalent antibodies against RP inhibit RP-cell adhesion as well as adheron-cell interactions. The RP protein is found in neural retina, but not in other tissues such as brain and muscle. These data suggest that RP plays a role in both the survival and adhesive interactions of neural retina cells. PMID:2993313

1985-01-01

113

Endocytosis Regulates Cell Soma Translocation and the Distribution of Adhesion Proteins in Migrating Neurons  

E-print Network

Endocytosis Regulates Cell Soma Translocation and the Distribution of Adhesion Proteins their attachments. We show that the machinery for clathrin- mediated endocytosis is positioned to regulate. These results suggest that endocytosis may play a critical role in regulating substrate detachment to enable

McConnell, Susan

114

Low-cost Soybean Protein Products as Extenders in Plywood Adhesives  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean flour and meal were evaluated as alternate protein extenders in plywood adhesives. This research is part of our laboratory’s efforts to develop new uses for the proteinaceous co-products from soybean and cereal processing. Ground soybean meal was tested as replacement for wheat flour in glu...

115

Low-Cost Soybean Protein Products as Extenders in Plywood Adhesives  

Technology Transfer Automated Retrieval System (TEKTRAN)

Soybean flour and meal were evaluated as alternate protein extenders in plywood adhesives. This research is part of our laboratory’s efforts to develop new uses for the proteinaceous co-products from soybean and cereal processing. Ground soybean meal was tested as replacement for wheat flour in gl...

116

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

117

Foaming properties of soybean protein-based plywood adhesives  

Microsoft Academic Search

A study was conducted to evaluate the potential of soy protein-based plywood glues for foam extrusion. Foaming properties\\u000a were the first criterion used to screen several soy protein sources. Foaming capacities and stabilities of glue mixes containing\\u000a animal blood (control) or soy products (meals, flours, concentrates, and isolates) were compared and correlated with molecular\\u000a weights and surface hydrophobicity indices (S

Milagros P. Hojilla-Evangelista; Larson B. Dunn

2001-01-01

118

Effects of Discrete Protein–Surface Interactions in Scanning Force Microscopy Adhesion Force Measurements  

PubMed Central

The potential for measuring specific molecular recognition forces between probe-bound ligands and surface-bound proteins using a scanning force microscope (SFM) has recently gained much attention. Generally, observed discontinuities in the SFM force-displacement curves are attributed to the breaking of discrete, specific affinity bonds. The present study on the molecular recognition system composed of surface-immobilized antifluorescyl IgG molecules and SFM probe-bound fluorescein ligands has demonstrated that similar intermittent discontinuities in the SFM force-displacement curves may in fact be largely due to nonspecific discrete interactions between the protein and the SFM probe. The mechanical behavior of the cantilever–spherical bead system used in this study is discussed, as it appears to cause a false indication of the separation distance between the surface and probe. The strong lateral interactions which result in “stick and slip”-like discontinuities seen in the adhesion curves are likely the result of localized adhesion due to the heterogeneous nature of proteins and the lack of molecular mobility allowed in the experimental system. The effect is magnified with increasing contact time between the protein and probe. Factors which may cause such anomalous behavior in a specific ligand–protein system are discussed in order to avoid misinterpretation of SFM adhesion measurements. PMID:25125793

Stuart, Joan K.; Hlady, Vladimir

2012-01-01

119

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. PMID:23554695

Bektas, Meryem; Rubenstein, David S.

2011-01-01

120

Studies on cell adhesion and recognition. I. Extent and specificity of cell adhesion triggered by carbohydrate-reactive proteins (glycosidases and lectins) and by fibronectin  

PubMed Central

The extent and the specificity of the initial cell attachment induced by various proteins coated on plastic surfaces have been studied with the following results: (a) Cell adhesion on the surfaces coated with sialidase and beta-galactosidase was as strong as on concanavalin A and limulus lectin-coated surfaces and the reactions were strongly inhibited by glycosidase inhibitors or by competitive substrates. The adhesion on sialidase was inhibited by 2-deoxy-2,3-dehydro-N- acetylneuraminic acid and by polysialoganglioside (GT1b) at low concentration (0.05-0.1 mM). The cell adhesion on beta-galactosidase coat was inhibited by 1,4-D-galactonolactone and beta-methylgalactoside but not by alpha-methylgalactoside. Thus, the initiation of cell adhesion on glycosidase surfaces could be mediated through the interactions of the specific binding sites of the enzyme surface with the cell surface substrates under physiological conditions. (b) Cell adhesion on various lectins could be blocked by various competing monosaccharides at the concentrations similar to the inhibitory concentrations for binding of lectins from solution to the cells. (c) Cell adhesion on fibronectin surfaces as well as on gelatin-coated surfaces was equally inhibited by GT1b at relatively high concentrations (0.25-0.5 mM). Lower concentrations of GT1b (0.05-0.1 mM) inhibited the cell adhesion on surfaces of Limulus lectin and sialidase. It is suggested that the cell adhesion mediated by fibronectin is based on yet unknown interactions in contrast to a specific cell adhesion through glycosidases and lectins. PMID:6782107

1981-01-01

121

Surface adhesion of fusion proteins containing the hydrophobins HFBI and HFBII from Trichoderma reesei  

PubMed Central

Hydrophobins are surface-active proteins produced by filamentous fungi, where they seem to be ubiquitous. They have a variety of roles in fungal physiology related to surface phenomena, such as adhesion, formation of surface layers, and lowering of surface tension. Hydrophobins can be divided into two classes based on the hydropathy profile of their primary sequence. We have studied the adhesion behavior of two Trichoderma reesei class II hydrophobins, HFBI and HFBII, as isolated proteins and as fusion proteins. Both hydrophobins were produced as C-terminal fusions to the core of the hydrolytic enzyme endoglucanase I from the same organism. It was shown that as a fusion partner, HFBI causes the fusion protein to efficiently immobilize to hydrophobic surfaces, such as silanized glass and Teflon. The properties of the surface-bound protein were analyzed by the enzymatic activity of the endoglucanase domain, by surface plasmon resonance (Biacore), and by a quartz crystal microbalance. We found that the HFBI fusion forms a tightly bound, rigid surface layer on a hydrophobic support. The HFBI domain also causes the fusion protein to polymerize in solution, possibly to a decamer. Although isolated HFBII binds efficiently to surfaces, it does not cause immobilization as a fusion partner, nor does it cause polymerization of the fusion protein in solution. The findings give new information on how hydrophobins function and how they can be used to immobilize fusion proteins. PMID:12192081

Linder, Markus; Szilvay, Geza R.; Nakari-Setälä, Tiina; Söderlund, Hans; Penttilä, Merja

2002-01-01

122

Glycopolymer functionalization of engineered spider silk protein-based materials for improved cell adhesion.  

PubMed

Silk protein-based materials are promising biomaterials for application as tissue scaffolds, due to their processability, biocompatibility, and biodegradability. The preparation of films composed of an engineered spider silk protein (eADF4(C16)) and their functionalization with glycopolymers are described. The glycopolymers bind proteins found in the extracellular matrix, providing a biomimetic coating on the films that improves cell adhesion to the surfaces of engineered spider silk films. Such silk-based materials have potential as coatings for degradable implantable devices. PMID:24700586

Hardy, John G; Pfaff, André; Leal-Egaña, Aldo; Müller, Axel H E; Scheibel, Thomas R

2014-07-01

123

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

2007-09-01

124

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

PubMed Central

An adhesive protein extracted from marine mussel (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, 0.5 mM dihydroxyphenylalanine) was applied, with or without the curing agents, to the ends of two overlapping strips of porcine small intestinal submucosa. The bond strength of this lap joint was determined after curing for 1 h at room temperature (25°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 25 mM 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 250 mM V5+ gave a very strong bond. PMID:17434815

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

2008-01-01

125

The multiple signaling modalities of adhesion G protein-coupled receptor GPR126 in development.  

PubMed

The G protein-coupled receptor (GPCR) superfamily is the largest known receptor family in the human genome. Although the family of adhesion GPCRs comprises the second largest sub-family, their function is poorly understood. Here, we review the current knowledge about the adhesion GPCR family member GPR126. GPR126 possesses a signal peptide, a 7TM domain homologous to secretin-like GPCRs, a GPS motif and an extended N-terminus containing a CUB (Complement, Uegf, Bmp1) domain, a PTX (Pentraxin) domain, a hormone binding domain and 27 putative N-glycosylation sites. Knockdown and knockout experiments in zebrafish and mice have demonstrated that Gpr126 plays an essential role in neural, cardiac and ear development. In addition, genome-wide association studies have implicated variations at the GPR126 locus in obstructive pulmonary dysfunction, in scoliosis and as a determinant of trunk length and body height. Gpr126 appears to exert its function depending on the organ system via G protein- and/or N-terminus-dependent signaling. Here, we review the current knowledge about Gpr126, which, due to the variety of its functions and its multiple signaling modalities, provides a model adhesion GPCR to understand general functional concepts utilized by adhesion GPCRs. PMID:25493288

Patra, Chinmoy; Monk, Kelly R; Engel, Felix B

2014-07-01

126

Choline phosphate functionalized surface: protein-resistant but cell-adhesive zwitterionic surface potential for tissue engineering.  

PubMed

A choline phosphate (CP) modified surface is designed to resist protein adsorption due to its zwitterionic properties and simultaneously promote cell adhesion though its universal interaction with phosphate choline (PC) headgroups of the cell membrane. This work provides a new approach to obtain a cell-adhesive surface with a non-biofouling 'background', which has a potential for tissue engineering. PMID:25408248

Chen, Xingyu; Chen, Tianchan; Lin, Zaifu; Li, Xian'e; Wu, Wei; Li, Jianshu

2015-01-11

127

Structural basis of the tensile strength of protein complexes mediating cell adhesion  

NASA Astrophysics Data System (ADS)

This study explores the behaviour of adhesive complexes of cell adhesion molecules undergoing forced detachment. Molecular-forces measurements combined with Steered Molecular Dynamic (SMD) simulations were used to investigate the mechanical response of the CD2 C58 and hemophilic C-cadherin bonds. The CD2-CD58 adhesive complex, important for the adaptive immune response, contains several salt-bridges in the adhesive interface. SMD simulations showed that these inter-protein salt bridges contribute independently to the tensile strength of the complex. Consistent with this, force measurements with the Surface Force Apparatus (SFA) demonstrated that the elimination of single salt bridges weakens the bond. The corresponding loss in adhesion energy of the CD2-CD58 complex correlates with the importance of the salt bridges observed in the simulations. These findings correlate closely with the effect of the elimination of single salt bridges observed in cell aggregation assays and binding measurements. On the other hand, the hemophilic C-cadherin interaction determines specific cell-cell adhesion during development in Xenopus laevis . Single molecule force spectroscopy was used to characterize the multiple bound states between C-cadherin ectodomains. The experiments showed two short-lived bound states associated with the two outermost ectodomains and two long-lived states associated with the full ectodomain. It is likely that the two short-lived states are involved in the specificity of the interaction since previous studies showed that the corresponding states in E-cadherin have different lifetimes. In addition, SMD simulations of the forced dissociation of the strand dieter of C-cadherin suggested a mechanism for the specificity of cadherin interactions.

Bayas, Marco Vinicio

128

A genome-wide screen identifies conserved protein hubs required for cadherin-mediated cell–cell adhesion  

PubMed Central

Cadherins and associated catenins provide an important structural interface between neighboring cells, the actin cytoskeleton, and intracellular signaling pathways in a variety of cell types throughout the Metazoa. However, the full inventory of the proteins and pathways required for cadherin-mediated adhesion has not been established. To this end, we completed a genome-wide (?14,000 genes) ribonucleic acid interference (RNAi) screen that targeted Ca2+-dependent adhesion in DE-cadherin–expressing Drosophila melanogaster S2 cells in suspension culture. This novel screen eliminated Ca2+-independent cell–cell adhesion, integrin-based adhesion, cell spreading, and cell migration. We identified 17 interconnected regulatory hubs, based on protein functions and protein–protein interactions that regulate the levels of the core cadherin–catenin complex and coordinate cadherin-mediated cell–cell adhesion. Representative proteins from these hubs were analyzed further in Drosophila oogenesis, using targeted germline RNAi, and adhesion was analyzed in Madin–Darby canine kidney mammalian epithelial cell–cell adhesion. These experiments reveal roles for a diversity of cellular pathways that are required for cadherin function in Metazoa, including cytoskeleton organization, cell–substrate interactions, and nuclear and cytoplasmic signaling. PMID:24446484

Toret, Christopher P.; D’Ambrosio, Michael V.; Vale, Ronald D.; Simon, Michael A.

2014-01-01

129

Localization of vascular adhesion protein-1 (VAP-1) in the human eye  

Microsoft Academic Search

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 therefore investigated by immunohistochemistry. Five micrometer thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs

Lama Almulki; Kousuke Noda; Shintaro Nakao; Toshio Hisatomi; Kennard L. Thomas; Ali Hafezi-Moghadam

2010-01-01

130

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

PubMed Central

A 20,000-D protein called purpurin has recently been isolated from the growth-conditioned medium of cultured embryonic chick neural retina cells (Schubert, D., and M. LaCorbiere, 1985, J. Cell Biol., 101:1071- 1077). 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 [3H]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 approximately 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. PMID:3754874

1986-01-01

131

Role of the focal adhesion protein TRIM15 in colon cancer development.  

PubMed

The tripartite motif containing (TRIM) proteins are a large family of proteins that have been implicated in many biological processes including cell differentiation, apoptosis, transcriptional regulation, and signaling pathways. Here, we show that TRIM15 co-localized to focal adhesions through homo-dimerization and significantly suppressed cell migration. Domain mapping analysis indicated that B-box2 and PRY domains were essential for TRIM15 localization to focal adhesions and inhibition of cell migration. Our protein-protein interaction screen of TRIM15 with the integrin adhesome identified several TRIM15 interacting proteins including coronin 1B, cortactin, filamin binding LIM protein1, and vasodilator-stimulated phosphoprotein, which are involved in actin cytoskeleton dynamics. TRIM15 expression was tissue-restricted and downregulated in colon cancer. Level of TRIM15 expression was associated with colon cancer cell migration, as well as both in vitro and in vivo tumor growth. These data provide novel insights into the role of TRIM15 as an additional component of the integrin adhesome, regulating cell migration, and suggest that TRIM15 may function as a tumor suppressor of colon cancer. PMID:25450970

Lee, Ok-Hee; Lee, Jinkyoung; Lee, Keun Ho; Woo, Yun Mi; Kang, Ju-Hee; Yoon, Ho-Geun; Bae, Soo-Kyung; Songyang, Zhou; Oh, Seung Hyun; Choi, Youngsok

2015-02-01

132

Differential phosphorylation of paxillin in response to surface-bound serum proteins during early osteoblast adhesion.  

PubMed

An early signaling event during the adhesion and spreading of cells is integrin-mediated tyrosine phosphorylation of the cytoskeletal adaptor protein paxillin and the non-receptor tyrosine kinase pp125(FAK) at focal contacts. To determine the influence of surface-charge and -adsorbed adhesion proteins on this signaling pathway, paxillin phosphorylation was examined during attachment of MC3T3-E1 osteoblast-like cell onto charged and uncharged polystyrene, and on adsorbed layers of serum proteins, fibronectin (Fn), vitronectin (Vn), a mixture of Fn and Vn, and albumin. Paxillin phosphorylation was induced 2.4-fold (P < 0.05) on charged vs uncharged polystyrene only in the presence of serum proteins. Activation of paxillin via Fn or Vn alone, or in combination, resulted in significantly lower phosphorylation signals compared to whole serum (41 +/- 6.9%, P < 0.05, 45 +/- 5.9%, P < 0.05, and 76 +/- 9.8%, P < 0.075, respectively). Confocal laser microscopy confirmed increased co-localization of phosphotyrosine and paxillin at protruding lamellopodia of spreading osteoblasts on charged vs uncharged serum-pretreated polystyrene. Taken together, these data suggest that subtle differences in surface characteristics mediate effects on adhering cells via adsorbed serum proteins involving the cytoskeletal adaptor protein paxillin. PMID:11444850

Sommerfeldt, D W; McLeod, K J; Rubin, C T; Hadjiargyrou, M

2001-07-13

133

Thrombin causes increased monocytic-cell adhesion to endothelial cells through a protein kinase C-dependent pathway.  

PubMed Central

The coagulation protein thrombin has been shown to stimulate multiple endothelial-cell (EC) functions, including production of platelet-derived growth factor and of platelet-activating factor (PAF), and neutrophil adhesion. We have found that thrombin causes increased binding of monocytic cells (U937 cells and normal human monocytes) to cultured EC of various species. Maximum adhesion of monocytes to pig aortic EC occurred 6 h after thrombin treatment and remained elevated through 24 h. Stimulation of adherence by bovine alpha-thrombin was half-maximal at 15 units/ml, and reached a plateau at 50 units/ml. Catalytically inactive thrombin (phenylmethanesulphonyl fluoride-treated) had no effect on monocyte adhesion to EC. Heparin, but not the endotoxin antagonist polymyxin B, suppressed the stimulation of adhesion by thrombin without altering basal adhesion. Two lines of evidence suggested that protein kinase C (PKC) was involved in the intracellular signalling to increase monocyte adhesion to EC. First the PKC activator phorbol 12-myristate 13-acetate (PMA) stimulated monocytic-cell adhesion to EC at a dose consistent with stimulation of PKC (half-maximal response at 1-3 nM) and with a time course similar to that for thrombin stimulation (maximal by 4 h). Diacylglycerol, a physiological activator of PKC, also stimulated U937-cell adhesion to EC. Secondly, H7, a PKC inhibitor, completely blocked stimulation of monocyte adhesion to EC by thrombin or PMA. The structural analogue of H7, HA1004, which preferentially inhibits cyclic-AMP- and cyclic-GMP-dependent protein kinases, had no effect on stimulated monocyte adhesion. The PKC inhibitor also blocked the stimulation of monocyte adhesion to EC by interleukin-1 and endotoxin, but did not alter the basal level of monocyte binding to unstimulated EC. Thrombin stimulation of monocyte adhesion differed from the reported stimulation of neutrophil adhesion by thrombin in that the latter process reached a maximum in minutes rather than hours. In addition, neither PAF itself nor agents known to stimulate PAF production by EC, such as arachidonate and the Ca2+ ionophore A23187, had any effect on monocyte adhesion. These results demonstrate a PKC-dependent cytokine-like action of the coagulation protein thrombin in modulating monocytic-cell adhesion to EC, a phenomenon of potential importance in many pathological and physiological processes. Images Fig. 4. PMID:2513808

DiCorleto, P E; de la Motte, C A

1989-01-01

134

Application of tung oil to improve adhesion strength and water resistance of cottonseed meal and protein adhesives on maple veneer  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cottonseed meal-based products show promise in serving as environment-friendly wood adhesives. However, their practical utilization is currently limited due to low durability and water resistant properties. In this research, we tested the improvement of adhesion strength and water resistance of cott...

135

Mitogen-activated protein kinase (MAPK) pathway regulates branching by remodeling epithelial cell adhesion.  

PubMed

Although the growth factor (GF) signaling guiding renal branching is well characterized, the intracellular cascades mediating GF functions are poorly understood. We studied mitogen-activated protein kinase (MAPK) pathway specifically in the branching epithelia of developing kidney by genetically abrogating the pathway activity in mice lacking simultaneously dual-specificity protein kinases Mek1 and Mek2. Our data show that MAPK pathway is heterogeneously activated in the subset of G1- and S-phase epithelial cells, and its tissue-specific deletion results in severe renal hypodysplasia. Consequently to the deletion of Mek1/2, the activation of ERK1/2 in the epithelium is lost and normal branching pattern in mutant kidneys is substituted with elongation-only phenotype, in which the epithelium is largely unable to form novel branches and complex three-dimensional patterns, but able to grow without primary defects in mitosis. Cellular characterization of double mutant epithelium showed increased E-cadherin at the cell surfaces with its particular accumulation at baso-lateral locations. This indicates changes in cellular adhesion, which were revealed by electron microscopic analysis demonstrating intercellular gaps and increased extracellular space in double mutant epithelium. When challenged to form monolayer cultures, the mutant epithelial cells were impaired in spreading and displayed strong focal adhesions in addition to spiky E-cadherin. Inhibition of MAPK activity reduced paxillin phosphorylation on serine 83 while remnants of phospho-paxillin, together with another focal adhesion (FA) protein vinculin, were augmented at cell surface contacts. We show that MAPK activity is required for branching morphogenesis, and propose that it promotes cell cycle progression and higher cellular motility through remodeling of cellular adhesions. PMID:24603431

Ihermann-Hella, Anneliis; Lume, Maria; Miinalainen, Ilkka J; Pirttiniemi, Anniina; Gui, Yujuan; Peränen, Johan; Charron, Jean; Saarma, Mart; Costantini, Frank; Kuure, Satu

2014-03-01

136

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

2013-01-01

137

Promyelocytic leukemia (PML) protein plays important roles in regulating cell adhesion, morphology, proliferation and migration.  

PubMed

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. PMID:23555679

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

138

Smad2/Smad3 in endothelium is indispensable for vascular stability via S1PR1 and N-cadherin expressions  

PubMed Central

Transforming growth factor-? (TGF-?) is involved in vascular formation through activin receptor-like kinase (ALK)1 and ALK5. ALK5, which is expressed ubiquitously, phosphorylates Smad2 and Smad3, whereas endothelial cell (EC)–specific ALK1 activates Smad1 and Smad5. Because ALK5 kinase activity is required for ALK1 to transduce TGF-? signaling via Smad1/5 in ECs, ALK5 knockout (KO) mice were not able to give us the precise mechanisms by which TGF-?/ALK5/Smad2/3 signaling is implicated in angiogenesis. To delineate the role of Smad2/3 signaling in endothelium, the Smad2 gene in Smad3 KO mice was selectively deleted in ECs using Tie2-Cre transgenic mice, termed EC-specific Smad2/3 double KO (EC-Smad2/3KO) mice. EC-Smad2/3KO embryos revealed hemorrhage leading to embryonic lethality around E12.5. EC-Smad2/3KO embryos exhibited no abnormality of vasculogenesis and angiogenesis in both the yolk sac and the whole embryo, whereas vascular maturation was incomplete because of inadequate assembly of mural cells in the vasculature. Wide gaps between ECs and mural cells could be observed in the vasculature of EC-Smad2/3KO mice because of reduced expression of N-cadherin and sphingosine-1-phosphate receptor-1 (S1PR1) in ECs from those mice. These results indicated that Smad2/3 signaling in ECs is indispensable for maintenance of vascular integrity via the fine-tuning of N-cadherin, VE-cadherin, and S1PR1 expressions in the vasculature. PMID:22498737

Itoh, Fumiko; Adachi, Tomomi; Ichikawa, Kei; Matsumura, Yutaka; Takagi, Takahiro; Festing, Maria; Watanabe, Takuya; Weinstein, Michael; Karlsson, Stefan; Kato, Mitsuyasu

2012-01-01

139

Platelet adhesion changes during storage studied with a novel method using flow cytometry and protein-coated beads.  

PubMed

Abstract The aim of the present study was to set up and evaluate a novel method for studies of platelet adhesion and activation in blood and platelet suspensions such as platelet concentrate (PC) samples using protein-coated polystyrene beads and flow cytometry. To demonstrate its usefulness, we studied PCs during storage. PCs were prepared by aphaeresis technique (n?=?7). Metabolic variables and platelet function was measured on day 1, 5, 7 and 12 of storage. Spontaneous and TRAP-6-induced adhesion to fibrinogen- and collagen-coated beads was analyzed by flow cytometry. P-selectin and phosphatidyl serine (PS) expression was assessed on platelets bound to beads as well as on non-adherent platelets. Platelet adhesion to fibrinogen beads had increased by day 12 and adhesion to collagen beads at day 7 of storage (p?adhesion to fibrinogen beads (p?adhesion assay using protein-coated polystyrene beads can be used to assess the adhesion properties of platelets during storage without the addition of red blood cells. Therefore it may offer a useful tool for future studies of platelet adhesive capacity in transfusion medicine and other settings. PMID:24679340

Tynngård, Nahreen; Wallstedt, Maria; Södergren, Anna L; Faxälv, Lars; Ramström, Sofia

2014-03-28

140

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. PMID:22235279

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

2012-01-01

141

Force Activation of a Multimeric Adhesive Protein through Domain Conformational Change  

NASA Astrophysics Data System (ADS)

The force-induced activation of adhesive proteins such as von Willebrand factor (VWF), which experience 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 pVWF multimers to bind platelets. Here we showed that a pathological level of high shear flow 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 multimeric VWF. We found that shear-activated pVWF multimers (spVWF) are more resistant to mechanical unfolding than non-sheared 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

142

Mechanical Activation of a Multimeric Adhesive Protein through Domain Conformational Change  

PubMed Central

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 multimeric VWF. We found that shear-activated pVWF multimers (spVWF) are more resistant to mechanical unfolding than non-sheared pVWF multimers, as indicated in the higher peak unfolding force. These results provide insight into the mechanism of shear-induced activation of pVWF multimers. PMID:23521301

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

2013-01-01

143

Adhesion of Fusobacterium necrophorum to bovine endothelial cells is mediated by outer membrane proteins.  

PubMed

Fusobacterium necrophorum, a Gram-negative anaerobe, is frequently associated with suppurative and necrotic infections of animals and humans. The organism is a major bovine pathogen, and in cattle, the common fusobacterial infections are hepatic abscesses, foot rot, and necrotic laryngitis. The species comprises two subspecies: F. necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme. Bacterial adhesion to the host cell surface is a critical initial step in the pathogenesis, and outer membrane proteins (OMP) play an important role in adhesion and establishment of certain Gram-negative bacterial infections. The means by which F. necrophorum attaches to epithelial or endothelial cells has not been determined. We evaluated whether OMP of F. necrophorum, isolated from a liver abscess, mediated adhesion to bovine endothelial cells (adrenal gland capillary endothelial cell line). The extent of binding of subsp. necrophorum to the endothelial cells was higher than that of F. necrophorum subsp. funduliforme. Trypsin treatment of bacterial cells decreased their binding to endothelial cells indicating the protein nature of adhesins. Preincubation of endothelial cells with OMP extracted from F. necrophorum decreased the binding of bacterial cells. In addition, binding of each subspecies to endothelial cells was inhibited by polyclonal antibodies raised against respective OMP and the antibody-mediated inhibition was subspecies specific. The western blot analysis of OMP bound to endothelial cells with anti-OMP antibodies showed four OMP of 17, 24, 40 and 74 kDa. We conclude that OMP of F. necrophorum play a role in adhesion of bacterial cells to the endothelial cells. PMID:23153522

Kumar, Amit; Gart, Elena; Nagaraja, T G; Narayanan, Sanjeev

2013-03-23

144

Highly purified mussel adhesive protein to secure biosafety for in vivo applications  

PubMed Central

Background Unique adhesive and biocompatibility properties of mussel adhesive proteins (MAPs) are known for their great potential in many tissue engineering and biomedical applications. Previously, it was successfully demonstrated that redesigned hybrid type MAP, fp-151, mass-produced in Gram-negative bacterium Escherichia coli, could be utilized as a promising adhesive biomaterial. However, purification of recombinant fp-151 has been unsatisfactory due to its adhesive nature and polarity which make separation of contaminants (especially, lipopolysaccharide, a toxic Gram-negative cell membrane component) very difficult. Results In the present work, we devised a high resolution purification approach to secure safety standards of recombinant fp-151 for the successful use in in vivo applications. Undesirable impurities were remarkably eliminated as going through sequential steps including treatment with multivalent ion and chelating agent for cell membrane washing, mechanical cell disruption, non-ionic surfactant treatment for isolated inclusion body washing, acid extraction of washed inclusion body, and ion exchange chromatography purification of acid extracted sample. Through various analyses, such as high performance liquid chromatographic purity assay, limulus amoebocyte lysate endotoxin assay, and in vitro mouse macrophage cell tests on inflammation, viability, cytotoxicity, and apoptosis, we confirmed the biological safety of bacterial-derived purified recombinant fp-151. Conclusions Through this purification design, recombinant fp-151 achieved 99.90% protein purity and 99.91% endotoxin reduction that nearly no inflammation response was observed in in vitro experiments. Thus, the highly purified recombinant MAP would be successfully used as a safety-secured in vivo bioadhesive for tissue engineering and biomedical applications. PMID:24725543

2014-01-01

145

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. PMID:23431142

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

2013-01-01

146

Onion yellow phytoplasma P38 protein plays a role in adhesion to the hosts.  

PubMed

Adhesins are microbial surface proteins that mediate the adherence of microbial pathogens to host cell surfaces. In Mollicutes, several adhesins have been reported in mycoplasmas and spiroplasmas. Adhesins P40 of Mycoplasma agalactiae and P89 of Spiroplasma citri contain a conserved amino acid sequence known as the Mollicutes adhesin motif (MAM), whose function in the host cell adhesion remains unclear. Here, we show that phytoplasmas, which are plant-pathogenic mollicutes transmitted by insect vectors, possess an adhesion-containing MAM that was identified in a putative membrane protein, PAM289 (P38), of the 'Candidatus Phytoplasma asteris,' OY strain. P38 homologs and their MAMs were highly conserved in related phytoplasma strains. While P38 protein was expressed in OY-infected insect and plant hosts, binding assays showed that P38 interacts with insect extract, and weakly with plant extract. Interestingly, the interaction of P38 with the insect extract depended on MAM. These results suggest that P38 is a phytoplasma adhesin that interacts with the hosts. In addition, the MAM of adhesins is important for the interaction between P38 protein and hosts. PMID:25302654

Neriya, Yutaro; Maejima, Kensaku; Nijo, Takamichi; Tomomitsu, Tatsuya; Yusa, Akira; Himeno, Misako; Netsu, Osamu; Hamamoto, Hiroshi; Oshima, Kenro; Namba, Shigetou

2014-12-01

147

A Model for Central Synaptic Junctional Complex Formation Based on the Differential Adhesive Specificities of the Cadherins  

Microsoft Academic Search

Cadherins control critical developmental events through well-documented homophilic interactions. In epithelia, they are hallmark constituents of junctions that mediate intercellular adhesion. Brain tissue expresses several cadherins, and we now show that two of these, neural (N)- and epithelial (E)-cadherin, are localized to synaptic complexes in mutually exclusive distributions. In cerebellum, N-cadherin is frequently found associated with synapses, some of which

Allison M Fannon; David R Colman

1996-01-01

148

Differential effect of actomyosin relaxation on the dynamic properties of focal adhesion proteins.  

PubMed

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. PMID:24039980

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

2013-01-01

149

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. PMID:24039980

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

2013-01-01

150

Antiadhesive properties of arabinogalactan protein from ribes nigrum seeds against bacterial adhesion of Helicobacter pylori.  

PubMed

Fruit extracts from black currants (Ribes nigrum L.) are traditionally used for treatment of gastritis based on seed polysaccharides that inhibit the adhesion of Helicobacter pylori to stomach cells. For detailed investigations an arabinogalactan protein (F2) was isolated from seeds and characterized concerning molecular weight, carbohydrate, amino acid composition, linkage, configuration and reaction with ?-glucosyl Yariv. Functional testing of F2 was performed by semiquantitative in situ adhesion assay on sections of human gastric mucosa and by quantitative in vitro adhesion assay with FITC-labled H. pylori strain J99 and human stomach AGS cells. Bacterial adhesins affected were identified by overlay assay with immobilized ligands. ¹²?I-radiolabeled F2 served for binding studies to H. pylori and interaction experiments with BabA and SabA. F2 had no cytotoxic effects against H. pylori and AGS cells; but inhibited bacterial binding to human gastric cells. F2 inhibited the binding of BabA and fibronectin-binding adhesin to its specific ligands. Radiolabeled F2 bound non-specifically to different strains of H. pylori; and to BabA deficient mutant. F2 did not lead to subsequent feedback regulation or increased expression of adhesins or virulence factors. From these data the non-specific interactions between F2 and the H. pylori lead to moderate antiadhesive effects. PMID:24662083

Messing, Jutta; Niehues, Michael; Shevtsova, Anna; Borén, Thomas; Hensel, Andreas

2014-01-01

151

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. PMID:21965292

Doherty, Gary J.; Åhlund, Monika K.; Howes, Mark T.; Morén, Björn; Parton, Robert G.; McMahon, Harvey T.; Lundmark, Richard

2011-01-01

152

Understanding Marine Mussel Adhesion  

PubMed Central

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 water-impervious 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. PMID:17990038

Roberto, Francisco F.

2007-01-01

153

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

154

Identification of an Arg-Gly-Asp (RGD) cell adhesion site in human immunodeficiency virus type 1 transactivation protein, tat  

Microsoft Academic Search

Tat, the transactivation factor of human im- munodeflciency virus type 1 (HIV-1), contains the highly conserved tripeptide sequence Arg-Gly-Asp (RGD) that characterizes sites for integrin-mediated cell adhesion. The tat protein was assayed for cell at- tachment activity by measuring the adhesion of mono- cytic, T lymphocytic, and skeletal muscle-derived cell lines to tat-coated substratum. All cell lines tested bound to

David A. Brake; Christine Debouck

1990-01-01

155

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

PubMed Central

The extracellular matrix molecule cytotactin is a multidomain protein that plays a role in cell migration, proliferation, and differentiation during development. To analyze the structure-function relationships of the different domains of this glycoprotein, we have prepared a series of fusion constructs in bacterial expression vectors. Results obtained using a number of adhesion assays suggest that at least four independent cell binding regions are distributed among the various cytotactin domains. Two of these are adhesive; two others appear to be counteradhesive in that they inhibit cell attachment to otherwise favorable substrates. The adhesive regions were mapped to the fibronectin type III repeats II-VI and the fibrinogen domain. The morphology of the cells plated onto these adhesive fragments differed; the cells spread on the fibronectin type III repeats as they do on fibronectin, but remained round on the fibrinogen domain. The counteradhesive properties of the molecule were mapped to the EGF-like repeats and the last two fibronectin type III repeats, VII-VIII. The latter region also contained a cell attachment activity that was observed only after proteolysis of the cells. Several cell types were used in these analyses, including fibroblasts, neurons, and glia, all of which are known to bind to cytotactin. The different domains exert their effects in a concentration-dependent manner and can be inhibited by an excess of the soluble molecule, consistent with the hypothesis that the observed properties are mediated by specific receptors. Moreover, it appears that some of these receptors are restricted to particular cell types. For example, glial cells bound better than neurons to the fibrinogen domain and fibroblasts bound better than glia and neurons to the EGF fragment. These results provide a basis for understanding the multiple activities of cytotactin and a framework for isolating different receptors that mediate the various cellular responses to this molecule. PMID:1383239

1992-01-01

156

Painting the Focal Adhesion: Fluorescent Protein Vinculin Fusions Blessing E. Ogbemudia, Jared D. Homan, Ericka B. Ramko and Michael W. Davidson  

E-print Network

Painting the Focal Adhesion: Fluorescent Protein Vinculin Fusions Blessing E. Ogbemudia, Jared D focal adhesions has been determined using GFP-tagged vinculin expressed in various cell lines. The picture that emerges is one in which vinculin stabilizes focal adhesions and thereby suppresses cell

Weston, Ken

157

Mechanistic studies on zymogen-activator and adhesion proteins (ZAAP) as thrombolytic drugs and bacterial virulence factors  

E-print Network

Mechanistic studies on zymogen-activator and adhesion proteins (ZAAP) as thrombolytic drugs proteins (ZAAPs). The mechanism of action for ZAAPs has been termed "molecular sexuality" where zymogen members. Parallel studies will be performed to unravel the details of molecular sexuality in both

158

Cdc42 Effector Protein 2 (XCEP2) is required for normal gastrulation and contributes to cellular adhesion in Xenopus laevis  

Microsoft Academic Search

BACKGROUND: Rho GTPases and their downstream effector proteins regulate a diverse array of cellular processes during embryonic development, including reorganization of cytoskeletal architecture, cell adhesion, and transcription. Changes in the activation state of Rho GTPases are converted into changes in cellular behavior by a diversity of effector proteins, which are activated in response to changes in the GTP binding state

Karen K Nelson; Richard W Nelson

2004-01-01

159

Signalling 'SELF' to phagocytes with adhesion proteins that turn off default engulfment  

NASA Astrophysics Data System (ADS)

'Marker of self' proteins are being discovered that reportedly have the important role in multicellular organisms of signalling self to the many phagocytes (macrophages, neutrophils, etc) in the body. These cells generally succeed in engulfing, degrading, or at least isolating (even by cell fusion into giant cells) foreign objects ranging from the microbes that have existed for eons to more modern implant biomaterials and injectibles. We have conducted wide-ranging studies aimed at clarifying the function of one 'marker of self' surface protein, CD47, found on all cells and its counter-receptor, SIRPa, found on phagocytes. The Ig domains of these proteins, from human and mouse, are being recombinantly expressed and used to not only verify binding to the suitable receptors in solution and on cells, but the proteins are also being used to begin evaluating the signaling dynamics that underlie phagocytosis inhibition through adhesion. Conceptually, activators of engulfment on the surfaces of targeted cells (complement , antibodies, etc.) compete with CD47-SIRPa signalling through phosphorylation cascades that couple to cytoskeleton activation in the phagocytes. Collectively the results suggest new protein-protein means of understanding and perhaps augmenting biocompatibility.

Discher, Dennis; Photos, Peter; Subramanian, Shyam; Parthasarathy, Ranganath

2004-03-01

160

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

2012-11-01

161

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. PMID:22615182

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

162

Beyond cell adhesion: the role of armadillo proteins in the heart.  

PubMed

Plakoglobin (PG, ?-Catenin, JUP), a member of the armadillo protein family and close homolog of ?-catenin, functions to link cell surface cadherin molecules with the cytoskeleton. PG is the only junctional component found in both desmosomes and adherens junctions and thus plays a critical role in the regulation of cell-cell adhesion. Similar to ?-catenin, PG is able to interact with components of the Wnt signaling pathway and directly affect gene expression by binding with LEF/TCF transcription factors. In addition, it has been proposed that PG functions primarily as a competitive inhibitor of ?-catenin transcriptional activity by sequestering LEF/TCF. Compared to ?-catenin, the contribution of PG as a transcriptional regulator in either physiological or pathological conditions is poorly understood. There is increasing clinical interest in PG as both a structural protein as well as a signaling molecule as mutations have been identified in the human PG gene that cause Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) and cutaneous syndromes. This review will discuss the connection between altered cell adhesion and gene expression and its contribution to disease pathogenesis. PMID:23022961

Swope, David; Li, Jifen; Radice, Glenn L

2013-01-01

163

Spontaneous unraveling of hagfish slime thread skeins is mediated by a seawater-soluble protein adhesive.  

PubMed

Hagfishes are known for their ability to rapidly produce vast quantities of slime when provoked. The slime is formed via the interaction between seawater and two components released by the slime glands: mucin vesicles from gland mucous cells, which swell and rupture in seawater to form a network of mucus strands, and intermediate filament-rich threads, which are produced within gland thread cells as tightly coiled bundles called skeins. A previous study showed that the unraveling of skeins from Atlantic hagfish (Myxine glutinosa) requires both the presence of mucins and hydrodynamic mixing. In contrast, skeins from Pacific hagfish (Eptatretus stoutii) unravel in the absence of both mucins and mixing. We tested the hypothesis that spontaneous unraveling of E. stoutii skeins is triggered by the dissolution of a seawater-soluble protein adhesive and the release of stored strain energy within the coiled thread. Here we show that, as predicted by this hypothesis, unraveling can be initiated by a protease under conditions in which unraveling does not normally occur. We also demonstrate, using high resolution scanning electron microscopy, that the treatment of skeins with solutions that cause unraveling also leads to the disappearance of surface and inter-thread features that remain when skeins are washed with stabilizing solutions. Our study provides a mechanism for the deployment of thread skeins in Pacific hagfish slime, and raises the possibility of producing novel biomimetic protein adhesives that are salt, temperature and kosmotrope sensitive. PMID:24744422

Bernards, Mark A; Oke, Isdin; Heyland, Andreas; Fudge, Douglas S

2014-04-15

164

Major membrane protein TDE2508 regulates adhesive potency in Treponema denticola.  

PubMed

The cultivation and genetic manipulation of Treponema denticola, a Gram-negative oral spirochaeta associated with periodontal diseases, is still challenging. In this study, we formulated a simple medium based on a commercially available one, and established a transformation method with high efficiency. We then analyzed proteins in a membrane fraction in T. denticola and identified 16 major membrane-associated proteins, and characterized one of them, TDE2508, whose biological function was not yet known. Although this protein, which exhibited a complex conformation, was presumably localized in the outer membrane, we did not find conclusive evidence that it was exposed on the cell surface. Intriguingly, a TDE2508-deficient mutant exhibited significantly increased biofilm formation and adherent activity on human gingival epithelial cells. However, the protein deficiency did not alter autoaggregation, coaggregation with Porphyromonas gingivalis, hemagglutination, cell surface hydrophobicity, motility, or expression of Msp which was reported to be an adherent molecule in this bacteria. In conclusion, the major membrane protein TDE2508 regulates biofilm formation and the adhesive potency of T. denticola, although the underlying mechanism remains unclear. PMID:24586498

Abiko, Yuki; Nagano, Keiji; Yoshida, Yasuo; Yoshimura, Fuminobu

2014-01-01

165

Girdin, an actin-binding protein, is critical for migration, adhesion, and invasion of human glioblastoma cells.  

PubMed

Girdin, an actin-binding protein, possesses versatile functions in a multitude of cellular processes. Although several studies have shown that Girdin is involved in the cell DNA synthesis, actin cytoskeleton rearrangement, and cell motility, the molecular mechanisms of Girdin in tumor development and progression remain elusive. In this study, through over-expression and siRNA experiments, we found that Girdin increased migration of LN229 human glioblastoma cells. On the other hand, reducing Girdin impaired F-actin polymerization, which is essential for cell morphogenesis and motility. Matrix metalloproteinase 2, critical in human glioma migration and invasion, was down-regulated upon Girdin reduction and led to decreased invasion in vitro and in vivo. In addition, silencing Girdin expression impaired the phosphorylation of two important adhesion molecules, integrin ?1 and focal adhesion kinase, resulting in cell adhesion defects. Our immunohistochemical study on human gliomas tissue sections indicated that Girdin expression was positively related with glioma malignancy, supporting the in vitro and in vivo results from cell lines. Collectively, our findings suggest a critical role for Girdin in glioma infiltration. We show that reduction of Girdin, an actin-binding protein, leads to impaired F-actin polymerization and down-regulated expression of matrix metallopeptidase protein 2 (MMP-2), phosphorylated integrin ?1, and phosphorylated focal adhesion kinase (FAK), which resulted in decreased migration, adhesion, and invasion of glioblastoma cells. Girdin was positively correlated with glioma malignancy and negatively associated with clinical prognosis, suggesting Girdin as a critical regulator in glioma infiltration. PMID:25060559

Gu, Feng; Wang, Li; He, Jia; Liu, Xiaoli; Zhang, Huikun; Li, Wenliang; Fu, Li; Ma, Yongjie

2014-11-01

166

Electrophoretic interactions between nitrocellulose membranes and proteins: Biointerface analysis and protein adhesion properties.  

PubMed

Protein adsorption onto membrane surfaces is important in fields related to separation science and biomedical research. This study explored the molecular interactions between protein, bovine serum albumin (BSA), and nitrocellulose films (NC) using electrokinetic phenomena and the effects of these interactions on the streaming potential measurements for different membrane pore morphologies and pH conditions. The data were used to calculate the streaming ratios of membranes-to-proteins and to compare these values to the electrostatic or hydrophobic attachment of the protein molecules onto the NC membranes. The results showed that different pH and membrane pore morphologies contributes to different protein adsorption mechanisms. The protein adsorption was significantly reduced under conditions where the membrane and protein have like-charges due to electrostatic repulsion. At the isoelectric point (IEP) of the protein, the repulsion between the BSA and the NC membrane was at the lowest; thus, the BSA could be easily attached onto the membrane/solution interface. In this case, the protein was considered to be in a compact layer without intermolecular protein repulsions. PMID:23732801

Low, S C; Shaimi, R; Thandaithabany, Y; Lim, J K; Ahmad, A L; Ismail, A

2013-10-01

167

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

168

Vascular adhesion protein-1 promotes liver inflammation and drives hepatic fibrosis.  

PubMed

Nonalcoholic fatty liver disease (NAFLD) encompasses a range of manifestations, including steatosis and cirrhosis. Progressive disease is characterized by hepatic leukocyte accumulation in the form of steatohepatitis. The adhesion molecule vascular adhesion protein-1 (VAP-1) is a membrane-bound amine oxidase that promotes leukocyte recruitment to the liver, and the soluble form (sVAP-1) accounts for most circulating monoamine oxidase activity, has insulin-like effects, and can initiate oxidative stress. Here, we determined that hepatic VAP-1 expression is increased in patients with chronic liver disease and that serum sVAP-1 levels are elevated in patients with NAFLD compared with those in control individuals. In 4 murine hepatic injury models, an absence or blockade of functional VAP-1 reduced inflammatory cell recruitment to the liver and attenuated fibrosis. Moreover, disease was reduced in animals expressing a catalytically inactive form of VAP-1, implicating enzyme activity in the disease pathogenesis. Within the liver, hepatic stromal cells expressed functional VAP-1, and evaluation of cultured cells revealed that sVAP-1 promotes leukocyte migration through catalytic generation of ROS, which depended on VAP-1 enzyme activity. VAP-1 enhanced stromal cell spreading and wound closure and modulated expression of profibrotic genes. Together, these results link the amine oxidase activity of VAP-1 with hepatic inflammation and fibrosis and suggest that targeting VAP-1 has therapeutic potential for NAFLD and other chronic fibrotic liver diseases. PMID:25562318

Weston, Chris J; Shepherd, Emma L; Claridge, Lee C; Rantakari, Pia; Curbishley, Stuart M; Tomlinson, Jeremy W; Hubscher, Stefan G; Reynolds, Gary M; Aalto, Kristiina; Anstee, Quentin M; Jalkanen, Sirpa; Salmi, Marko; Smith, David J; Day, Christopher P; Adams, David H

2015-02-01

169

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. PMID:23236467

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

2012-01-01

170

Amyloid beta precursor protein and prion protein have a conserved interaction affecting cell adhesion and CNS development.  

PubMed

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 PrP(C) 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. PMID:23236467

Kaiser, Darcy M; Acharya, Moulinath; Leighton, Patricia L A; Wang, Hao; Daude, Nathalie; Wohlgemuth, Serene; Shi, Beipei; Allison, W Ted

2012-01-01

171

Novel pyridazinone inhibitors for vascular adhesion protein-1 (VAP-1): old target-new inhibition mode.  

PubMed

Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific, and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity, and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases. The crystal structures of three inhibitor-VAP-1 complexes show that these compounds bind reversibly into a unique binding site in the active site channel. Although they are good inhibitors of human VAP-1, they do not inhibit rodent VAP-1 well. To investigate this further, we used homology modeling and structural comparison to identify amino acid differences, which explain the species-specific binding properties. Our results prove the potency and specificity of these new inhibitors, and the detailed characterization of their binding mode is of importance for further development of VAP-1 inhibitors. PMID:24304424

Bligt-Lindén, Eva; Pihlavisto, Marjo; Szatmári, István; Otwinowski, Zbyszek; Smith, David J; Lázár, László; Fülöp, Ferenc; Salminen, Tiina A

2013-12-27

172

Development of robust biocompatible silicone with high resistance to protein adsorption and bacterial adhesion.  

PubMed

A new biocompatible silicone comprising a carboxybetaine (CB) ester analogue, 3-methacryloxypropyltris(trimethylsiloxy)silane (TRIS) and an organic silicone macromer (bis-?,?-(methacryloxypropyl) polydimethylsiloxane) has been developed using photo-polymerisation. Following interfacial hydrolysis of the CB ester, the resulting zwitterionic material became significantly more hydrophilic and exhibited high resistance to both non-specific protein adsorption and bacterial adhesion. Moreover, the stability of these non-fouling properties was dramatically improved by using a slow and controlled rate of ester hydrolysis of the original protective hydrophobic matrix. The subsequent ability to maintain the original optical and mechanical properties of the bare silicone following surface activation makes this material an ideal candidate for preparing contact lenses and other medical devices. PMID:21300187

Lin, Weifeng; Zhang, Juan; Wang, Zhen; Chen, Shengfu

2011-05-01

173

A higher plant extracellular vitronectin-like adhesion protein is related to the translational elongation factor-1 alpha.  

PubMed Central

Higher plant proteins immunologically related to the animal substrate adhesion molecule vitronectin have recently been observed and implicated in a variety of biological processes, such as plasma membrane-cell wall adhesion, pollen tube extension, and bacterium-plant interaction. We provide evidence that, similar to vitronectin, one of these proteins, PVN1 (plant vitronectin-like 1), isolated from 428 mM NaCl-adapted tobacco cells binds to glass surfaces an heparin. PVN1 was isolated by glass bead affinity chromatography. Isolated PVN1 has adhesive activity based on results from a baby hamster kidney cell-spreading assay. This plant adhesion protein was detected in all tissues examined but was most abundant in roots and salt-adapted cultured cells. Immunogold labeling indicated that PVN1 is localized in the cell wall of cortical and transmitting tissue cells of pollinated mature styles. A partial amino acid sequence of PVN1 revealed no similarity with vitronectin but, instead, was nearly identical to the translational elongation factor-1 alpha (EF-1 alpha). A clone isolated by screening a tobacco cDNA expression library with anti-PVN1 encoded a protein with greater than 93% identity to sequences of EF-1 alpha from plants of numerous species. Immunological cross-reactivity between tobacco PVN1 and EF-1 alpha as well as the reaction between the EF-1 alpha antibody and the 65- and 75-kD vitronectin-like proteins of a fucoidal alga supported the conclusion that the plant extracellular adhesion protein PVN1 is related to EF-1 alpha. PMID:7514059

Zhu, J K; Damsz, B; Kononowicz, A K; Bressan, R A; Hasegawa, P M

1994-01-01

174

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

175

Structure and expression of the silk adhesive protein Ser2 in Bombyx mori Barbara Kludkiewicz a,b  

E-print Network

Structure and expression of the silk adhesive protein Ser2 in Bombyx mori Barbara Kludkiewicz a in revised form 27 November 2009 Accepted 30 November 2009 Keywords: Silkworm Sericin Cocoon Silk gland Repetitive sequence a b s t r a c t Sericins are soluble silk components encoded in Bombyx mori by three

Â?urovec, Michal

176

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

E-print Network

, butyl or octyl cyanoacrylate adhesives were determined. Although joints bonded using ethyl cyanoacrylate Surgical adhesives are increasingly being used in soft tissue repair as fasteners and sealants because [40] reported that the mussel adhesive formed weak bonds. These investigators used distinctly 1742

Shi, Riyi

177

Osteoblast-specific factor 2: cloning of a putative bone adhesion protein with homology with the insect protein fasciclin I.  

PubMed Central

A cDNA library prepared from the mouse osteoblastic cell line MC3T3-E1 was screened for the presence of specifically expressed genes by employing a combined subtraction hybridization/differential screening approach. A cDNA was identified and sequenced which encodes a protein designated osteoblast-specific factor 2 (OSF-2) comprising 811 amino acids. OSF-2 has a typical signal sequence, followed by a cysteine-rich domain, a fourfold repeated domain and a C-terminal domain. The protein lacks a typical transmembrane region. The fourfold repeated domain of OSF-2 shows homology with the insect protein fasciclin I. RNA analyses revealed that OSF-2 is expressed in bone and to a lesser extent in lung, but not in other tissues. Mouse OSF-2 cDNA was subsequently used as a probe to clone the human counterpart. Mouse and human OSF-2 show a high amino acid sequence conservation except for the signal sequence and two regions in the C-terminal domain in which 'in-frame' insertions or deletions are observed, implying alternative splicing events. On the basis of the amino acid sequence homology with fasciclin I, we suggest that OSF-2 functions as a homophilic adhesion molecule in bone formation. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:8363580

Takeshita, S; Kikuno, R; Tezuka, K; Amann, E

1993-01-01

178

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. PMID:20159149

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

2010-01-01

179

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. PMID:24133488

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

2013-01-01

180

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

PubMed

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. PMID:24133488

Chagnot, Caroline; Zorgani, Mohamed A; Astruc, Thierry; Desvaux, Mickaël

2013-01-01

181

Hematopoietic PBX-interacting protein (HPIP) is over expressed in breast infiltrative ductal carcinoma and regulates cell adhesion and migration through modulation of focal adhesion dynamics.  

PubMed

The scaffolding protein, hematopoietic PBX-interacting protein (HPIP/PBXIP1), regulates cell migration necessary for cancer cell dissemination. However, the mechanism that governs this process remains unknown. We show here that HPIP expression is associated with stages of breast cancer where cell dissemination results in poor patient outcome. Our investigation finds a novel association of HPIP with focal adhesion kinase (FAK) regulating FA dynamics. Interestingly, this interaction that led to activation of FAK protein was mediated by the C-terminal domain of HPIP and not the typical integrin-binding motif. Further, short hairpin RNA-mediated knockdown of FAK expression significantly reduced HPIP-induced cell migration indicating participation of FAK pathway. Live-cell time-lapse imaging and biochemical analysis further established the role of HPIP in microtubule-induced FA disassembly. We also found that HPIP-mediated MAPK activation led to phosphorylation and subsequent activation of calpain2, and the activated calpain2 in turn proteolyses FA protein, talin. Interestingly, HPIP is also proteolysed by calpain2 in breast cancer cells. The proteolysis of HPIP and talin by calpain2, and the activation of calapin2 by HPIP-mediated MAPK phosphorylation, is a novel regulatory axis to modulate the cell migration signal. Together, we have determined HPIP as a novel activator of FAK and a new substrate of calpain2. These molecular interactions between HPIP and FAK, and HPIP and calpain2 regulate cell adhesion and migration through modulation of FA dynamics.Oncogene advance online publication, 8 December 2014; doi:10.1038/onc.2014.389. PMID:25486428

Bugide, S; David, D; Nair, A; Kannan, N; Samanthapudi, V S K; Prabhakar, J; Manavathi, B

2014-12-01

182

New functions and signaling mechanisms for the class of adhesion G protein-coupled receptors.  

PubMed

The class of adhesion G protein-coupled receptors (aGPCRs), with 33 human homologs, is the second largest family of GPCRs. In addition to a seven-transmembrane ?-helix-a structural feature of all GPCRs-the class of aGPCRs is characterized by the presence of a large N-terminal extracellular region. In addition, all aGPCRs but one (GPR123) contain a GPCR autoproteolysis-inducing (GAIN) domain that mediates autoproteolytic cleavage at the GPCR autoproteolysis site motif to generate N- and a C-terminal fragments (NTF and CTF, respectively) during protein maturation. Subsequently, the NTF and CTF are associated noncovalently as a heterodimer at the plasma membrane. While the biological function of the GAIN domain-mediated autocleavage is not fully understood, mounting evidence suggests that the NTF and CTF possess distinct biological activities in addition to their function as a receptor unit. We discuss recent advances in understanding the biological functions, signaling mechanisms, and disease associations of the aGPCRs. PMID:25424900

Liebscher, Ines; Ackley, Brian; Araç, Demet; Ariestanti, Donna M; Aust, Gabriela; Bae, Byoung-Il; Bista, Bigyan R; Bridges, James P; Duman, Joseph G; Engel, Felix B; Giera, Stefanie; Goffinet, André M; Hall, Randy A; Hamann, Jörg; Hartmann, Nicole; Lin, Hsi-Hsien; Liu, Mingyao; Luo, Rong; Mogha, Amit; Monk, Kelly R; Peeters, Miriam C; Prömel, Simone; Ressl, Susanne; Schiöth, Helgi B; Sigoillot, Séverine M; Song, Helen; Talbot, William S; Tall, Gregory G; White, James P; Wolfrum, Uwe; Xu, Lei; Piao, Xianhua

2014-12-01

183

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

2013-12-01

184

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

2013-07-01

185

Early Growth Response Protein 1 Promotes Restenosis by Upregulating Intercellular Adhesion Molecule-1 in Vein Graft  

PubMed Central

Objectives. To verify the relationship between Egr-1 and vein graft restenosis and investigate the related mechanisms. Methods. Mouse vein graft models were established in Egr-1 knockout (KO) and wild-type (WT) mice. The vein grafts in the mice were taken for pathological examination and immunohistochemical analysis. The endothelial cells (ECs) were stimulated by using a computer-controlled cyclic stress unit. BrdU staining and PCR were used to detect ECs proliferation activity and Egr-1 and ICAM-1 mRNA expression, respectively. Western-blot analysis was also used to detect expression of Egr-1 and intercellular adhesion molecule-1 (ICAM-1) proteins. Results. The lumens of vein grafts in Egr-1 KO mice were wider than in WT mice. ECs proliferation after mechanical stretch stimulation was suppressed by Egr-1 knockout (P < 0.05). Both in vein grafts and ECs from WT mice after mechanical stretch stimulation, mRNA expression and protein of Egr-1 and ICAM-1 showed increases (P < 0.05). However, ICAM-1 expression was significantly suppressed in ECs from Egr-1 knockout mice (P < 0.05). Conclusions. Egr-1 may promote ECs proliferation and result in vein graft restenosis by upregulating the expression of ICAM-1. As a key factor of vein graft restenosis, it could be a target for the prevention of restenosis after CABG surgery. PMID:24386503

Zhang, Kui; Cao, Jian; Dong, Ran; Du, Jie

2013-01-01

186

Negative regulation of monocyte adhesion to arterial elastic laminae by signal regulatory protein alpha and Src homology 2 domain-containing protein-tyrosine phosphatase-1.  

PubMed

Elastic laminae are extracellular matrix constituents that not only contribute to the stability and elasticity of arteries but also play a role in regulating arterial morphogenesis and pathogenesis. We demonstrate here that an important function of arterial elastic laminae is to prevent monocyte adhesion, which is mediated by the inhibitory receptor signal regulatory protein (SIRP) alpha and Src homology 2 domain-containing protein-tyrosine phosphatase (SHP)-1. In a matrix-based arterial reconstruction model in vivo, elastic laminae were resistant to leukocyte adhesion and transmigration compared with the collagen-dominant arterial adventitia. The density of leukocytes within the elastic lamina-dominant media was about 58-70-fold lower than that within the adventitia from 1 to 30 days. An in vitro assay confirmed the inhibitory effect of elastic laminae on monocyte adhesion. The exposure of monocytes to elastic laminae induced activation of SIRP alpha, which in turn activated SHP-1. Elastic lamina degradation peptides extracted from arterial specimens could also activate SIRP alpha and SHP-1. The knockdown of SIRP alpha and SHP-1 by specific small interfering RNA diminished the inhibitory effect of elastic laminae, resulting in a significant increase in monocyte adhesion. These observations suggest that SIRP alpha and SHP-1 potentially mediate the inhibitory effect of elastic laminae on monocyte adhesion. PMID:16159885

Liu, Shu Q; Alkema, Paul K; Tieché, Christopher; Tefft, Brandon J; Liu, Diana Z; Li, Yan Chun; Sumpio, Bauer E; Caprini, Joseph A; Paniagua, Mary

2005-11-25

187

The evaluation of p,p'-DDT exposure on cell adhesion of hepatocellular carcinoma.  

PubMed

Many studies have found a positive association between the progression of hepatocellular carcinoma and DDT exposure. These studies mainly focus on the effect of DDT exposure on cell proliferation and epithelial to mesenchymal transition (EMT) promotion. However, the influence of DDT on cell adhesion of hepatocellular carcinoma remains to be unclear. The aim of our study was to determine the effect of p,p'-DDT on cell adhesion of hepatocellular carcinoma in vitro and in vivo. The data showed that p,p'-DDT, exposing HepG2 cells for 6 days, decreased cell-cell adhesion and elevated cell-matrix adhesion. Strikingly, p,p'-DDT increased reactive oxygen species (ROS) content, and this was accompanied by the activation of JAK/STAT3 pathway. Moreover, ROS inhibitor supplement reversed these effects significantly. However, the addition of ER inhibitor, ICI, had no effect on the p,p'-DDT-induced effects. p,p'-DDT altered the mRNA levels of related adhesion molecules, including inhibition of E-cadherin and promotion of N-cadherin along with CD29. Interestingly, the p,p'-DDT-altered adhesion molecules could be reversed with JAK inhibitor or STAT3 inhibitor. Likewise, p,p'-DDT stimulated the JAK/STAT3 pathway in nude mice, as well as altered the mRNA levels of E-cadherin, N-cadherin, and CD29. Taken together, these results indicate that p,p'-DDT profoundly promotes the adhesion process by decreasing cell-cell adhesion and inducing cell-matrix adhesion via the ROS-mediated JAK/STAT3 pathway. All these events account for the carcinogenic potential of p,p'-DDT in liver. PMID:24820114

Jin, Xiaoting; Chen, Meilan; Song, Li; Li, Hanqing; Li, Zhuoyu

2014-08-01

188

Human DCXR - another 'moonlighting protein' involved in sugar metabolism, carbonyl detoxification, cell adhesion and male fertility?  

PubMed

Dicarbonyl/l-xylulose reductase (DCXR; SDR20C1), a member of the short-chain dehydrogenase/reductase (SDR) superfamily catalyzes the reduction of ?-dicarbonyl compounds and monosaccharides. Its role in the metabolism of l-xylulose has been known since 1970, when essential pentosuria was found to be associated with DCXR deficiency. Despite its early discovery, our knowledge about the role of human DCXR in normal physiology and pathophysiology is still incomplete. Sporadic studies have demonstrated aberrant expression in several cancers, but their physiological significance is unknown. In reproductive medicine, where DCXR is commonly referred to as 'sperm surface protein P34H', it serves as marker for epididymal sperm maturation and is essential for gamete interaction and successful fertilization. DCXR exhibits a multifunctional nature, both acting as a carbonyl reductase and also performing non-catalytic functions, possibly resulting from interactions with other proteins. Recent observations associate DCXR with a role in cell adhesion, pointing to a novel function involving tumour progression and possibly metastasis. This review summarizes the current knowledge about human DCXR and its orthologs from mouse and Caenorhabditis elegans (DHS-21) with an emphasis on its multifunctional characteristics. Due to its close structural relationship with DCXR, carbonyl reductase 2 (Cbr2), a tetrameric enzyme found in several non-primate species is also discussed. Similar to human DCXR, Cbr2 from golden hamster (P26h) and cow (P25b) is essential for sperm-zona pellucida interaction and fertilization. Because of the apparent similarity of these two proteins and the inconsistent use of alternative names previously, we provide an overview of the systematic classification of DCXR and Cbr2 and a phylogenetic analysis to illustrate their ancestry. PMID:24720935

Ebert, Bettina; Kisiela, Michael; Maser, Edmund

2015-02-01

189

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. PMID:23319980

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

2012-01-01

190

The cancer chemopreventive agent resveratrol induces tensin, a cell-matrix adhesion protein with signaling and antitumor activities.  

PubMed

During a search to identify resveratrol (3,5,4'-trihydroxy-trans-stilbene, RV) target genes in the human erythroleukemic K562 cell line, we show here that the tensin gene and protein levels are remarkably induced by this dietary polyphenol. Tensin, a cell-matrix adhesion protein binding the integrins and cytoskeletal actin filaments also interacts with PI3-kinase and JNK signaling pathways. Tensin induction by RV is associated with increased K562 cell adhesion to fibronectin, cell spreading and actin polymerization. The same responses were observed in the tensin-deficient MCF7 human breast cancer cell line. In K562 and MCF7 cells treated by RV, tensin was found in punctate and intracytoplasmic areas. In MCF7 epithelial cells, induction of tensin is not exclusively associated with plasma membrane-bound vinculin, suggesting a dual localization of tensin in both focal and fibrillar adhesions. Pharmacological blockade of PI3-kinase and Rho GTPases/Rho-kinase resulted in selective depletion of focal adhesions, disorganization of tensin localization and disruption of stress fibers. RV increased cell motility and attachment to fibronectin in MCF7 cells submitted to mechanical laminar flow stress, and abrogated estrogen-induced MCF7 cancer cell invasion. Our data support the conclusion that induction of tensin by RV contributes to the chemopreventive and anti-invasive activity of this natural dietary compound in tensin-negative and -deficient leukemic cells or epithelioid cancers. PMID:15735708

Rodrigue, Christelle M; Porteu, Françoise; Navarro, Nicole; Bruyneel, Erik; Bracke, Marc; Romeo, Paul-Henri; Gespach, Christian; Garel, Marie-Claude

2005-05-01

191

Modulation of endogenous Cysteine Protease Inhibitor (ICP) 1 expression in Entamoeba histolytica affects amoebic adhesion to Extracellular Matrix proteins.  

PubMed

Entamoeba histolytica is an enteric tissue-invading protozoan parasite that causes amoebic colitis and occasionally liver abscess in humans. During tissue invasion, amoebic adhesion to host components is an important event for host cell death leading to successful invasion and infection. Among amoebic virulence factors, Gal/GalNAc lectin is known to be major adhesion factor to host cells. In this study, we investigated the role of amoebic secreted CP (Cysteine Proteases) in amoebic adhesion to extracellular matrix (ECM) protein using CP inhibitor and E. histolytica strains in which the endogenous inhibitor of cysteine protease (ICP) 1 gene was overexpressed (ICP1(+)) or repressed by antisense small RNA-mediated gene silencing (ICP1(-)). We found that pretreatment of wild-type amoebae with CP inhibitor E64, or thiol-group modifiers such as diamide and N-Ethylmaleimide resulted in a significant decrease in adhesion to laminin and collagen ECM proteins. Furthermore, ICP1(+) strain, with a reduction of secreted CP activity, exhibited reduced ability by 40% to adhere to laminin. In contrast, ICP1(-) strain, with a 1.9-fold increase of secreted CP activity, showed a two-fold increase in amoebic adherence to laminin compared to the control strain. In addition, total amount of secreted CP5 was decreased in ICP1(+) amoeba. Conversely, total amount of secreted CP1 and mature-form CP5 were increased in ICP1(-) amoeba. We also found that ICP1 was secreted into extracellular milieu. These results suggest that secreted CP activity by E. histolytica may be an important factor affecting adhesion to host proteins, and regulation of CP secretion by ICP plays a major role in pathogenesis. This study provides insight into the CP-mediated tissue pathogenesis in amoeba-invaded lesions during human amoebiasis. PMID:25500214

Lee, Young Ah; Saito-Nakano, Yumiko; Kim, Kyeong Ah; Min, Arim; Nozaki, Tomoyoshi; Shin, Myeong Heon

2015-02-01

192

Enhanced Adhesion of Campylobacter jejuni to Abiotic Surfaces Is Mediated by Membrane Proteins in Oxygen-Enriched Conditions  

PubMed Central

Campylobacter jejuni is responsible for the major foodborne bacterial enteritis in humans. In contradiction with its fastidious growth requirements, this microaerobic pathogen can survive in aerobic food environments, suggesting that it must employ a variety of protection mechanisms to resist oxidative stress. For the first time, C. jejuni 81–176 inner and outer membrane subproteomes were analyzed separately using two-dimensional protein electrophoresis (2-DE) of oxygen-acclimated cells and microaerobically grown cells. LC-MS/MS analyses successfully identified 42 and 25 spots which exhibited a significantly altered abundance in the IMP-enriched fraction and in the OMP-enriched fraction, respectively, in response to oxidative conditions. These spots corresponded to 38 membrane proteins that could be grouped into different functional classes: (i) transporters, (ii) chaperones, (iii) fatty acid metabolism, (iv) adhesion/virulence and (v) other metabolisms. Some of these proteins were up-regulated at the transcriptional level in oxygen-acclimated cells as confirmed by qRT-PCR. Downstream analyses revealed that adhesion of C. jejuni to inert surfaces and swarming motility were enhanced in oxygen-acclimated cells or paraquat-stressed cells, which could be explained by the higher abundance of membrane proteins involved in adhesion and biofilm formation. The virulence factor CadF, over-expressed in the outer membrane of oxygen-acclimated cells, contributes to the complex process of C. jejuni adhesion to inert surfaces as revealed by a reduction in the capability of C. jejuni 81–176 ?CadF cells compared to the isogenic strain. Taken together, these data demonstrate that oxygen-enriched conditions promote the over-expression of membrane proteins involved in both the biofilm initiation and virulence of C. jejuni. PMID:23029510

Sulaeman, Sheiam; Hernould, Mathieu; Schaumann, Annick; Coquet, Laurent; Bolla, Jean-Michel; Dé, Emmanuelle; Tresse, Odile

2012-01-01

193

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

2013-03-15

194

Anti-neutrophil cytoplasmic antibody-enriched IgG induces adhesion of human T lymphocytes to extracellular matrix proteins.  

PubMed

Recent studies have shown that anti-neutrophil cytoplasmic antibodies (ANCA) can activate neutrophils to adhere to endothelium, degranulate, and cause endothelial cell injury. These data have lead to the hypothesis that the T cell inflammatory response causing the vasculitis in Wegener's granulomatosis (WG) is secondary to stimulation of neutrophils by ANCA. So far there is no evidence for a direct effect of ANCA on lymphocytes. The present study was designed to examine whether lymphocytes can be directly stimulated by ANCA to adhere to endothelial extracellular matrix (ECM) proteins. Human and mouse ANCA-enriched IgG were tested for their ability to increase adhesion of human T lymphocytes to fibronectin, laminin, and intact ECM. Incubation of human T lymphocytes with human ANCA-enriched IgG increased adhesion of the lymphocytes in a dose-dependent manner to fibronectin, laminin, and intact ECM (the percentage adhesion to intact ECM was 55.7 +/- 3.1 and 45.0 +/- 1.0% for lymphocytes incubated with human IgG containing ANCA or control human IgG, respectively; P = 0.0045). The same induction of adhesion to fibronectin, laminin, and intact ECM was observed when the cells were incubated with the F(ab)2 fragment of ANCA-enriched IgG. Similarly, ANCA-enriched IgG produced in mice increased the adhesion of lymphocytes to fibronectin (the percentage adhesion to fibronectin was 29.7 +/- 4.3 and 16.6 +/- 1.9% for lymphocytes incubated with mouse IgG-ANCA or control mouse IgG, respectively; P = 0.0008). These results may suggest that ANCA can directly stimulate lymphocytes to adhere to endothelial ECM and to induce the vasculitic lesions of WG. It remains to be shown by which mechanisms ANCA stimulate lymphocytes to adhere to ECM. PMID:9175913

Tomer, Y; Lider, O; Gilburd, B; Hershkoviz, R; Meroni, P L; Wiik, A; Shoenfeld, Y

1997-06-01

195

Functional correlation between cell adhesive properties and some cell surface proteins  

Microsoft Academic Search

The adhesive properties of Chinese hamster V79 cells were analyzed and charac- terized by various cell dissociation treatments. The comparisons of aggregatability among cells dissociated with EDTA, trypsin + Ca z+, and trypsin + EDTA, revealed that these cells have two adhesion mechanisms, a Ca2+-independent and a Ca2+-dependent one. The former did not depend on temperature, whereas the latter occurred

MASATOSHI TAKEICHI

1977-01-01

196

MEASUREMENTS OF CONFORMATION CHANGES DURING ADHESION OF LIPID PROTEIN (POLYLYSINE AND S-LAYER) SURFACES  

EPA Science Inventory

The adhesion forces between various surfaces were measured using the "surface forces apparatus" technique which allows for the thickness of surface layers and the adhesion force between them to be directly measured in controlled vapor or liquid environments. hree types of biologi...

197

Binding of neural cell adhesion molecules (N-CAMs) to the cellular prion protein.  

PubMed

To identify molecular interaction partners of the cellular prion protein (PrP(C)), we sought to apply an in situ crosslinking method that maintains the microenvironment of PrP(C). Mild formaldehyde crosslinking of mouse neuroblastoma cells (N2a) that are susceptible to prion infection revealed the presence of PrP(C) in high molecular mass (HMM) protein complexes of 200 to 225 kDa. LC/MS/MS analysis identified three murine splice-variants of the neural cell adhesion molecule (N-CAM) in the complexes, which isolate with caveolae-like domains (CLDs). Enzymatic removal of N-linked sugar moieties did not disrupt the complexes, arguing that the interaction of PrP with N-CAM occurs through amino acid side-chains. Additionally, similar levels of PrP/N-CAM complexes were found in N2a and prion-infected N2a (ScN2a) cells. With the use of an N-CAM-specific peptide library, the PrP-binding site was determined to comprise beta-strands C and C' within the two consecutive fibronectin type III (FNIII) modules found in proximity of the membrane-attachment site of N-CAM. As revealed by in situ crosslinking of PrP deletion mutants, the PrP face of the binding site is formed by the N terminus, helix A (residues 144-154) and the adjacent loop region of PrP. N-CAM-deficient (N-CAM(-/-)) mice that were intracerebrally challenged with scrapie prions succumbed to disease with a mean incubation period of 122 (+/-4.1, SEM) days, arguing that N-CAM is not involved in PrP(Sc) replication. Our findings raise the possibility that N-CAM may join with PrP(C) in carrying out some as yet unidentified physiologic cellular function. PMID:11743735

Schmitt-Ulms, G; Legname, G; Baldwin, M A; Ball, H L; Bradon, N; Bosque, P J; Crossin, K L; Edelman, G M; DeArmond, S J; Cohen, F E; Prusiner, S B

2001-12-14

198

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

PubMed Central

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.

2013-01-01

199

Collagen gel three-dimensional matrices combined with adhesive proteins stimulate neuronal differentiation of mesenchymal stem cells  

PubMed Central

Three-dimensional gel matrices provide specialized microenvironments that mimic native tissues and enable stem cells to grow and differentiate into specific cell types. Here, we show that collagen three-dimensional gel matrices prepared in combination with adhesive proteins, such as fibronectin (FN) and laminin (LN), provide significant cues to the differentiation into neuronal lineage of mesenchymal stem cells (MSCs) derived from rat bone marrow. When cultured within either a three-dimensional collagen gel alone or one containing either FN or LN, and free of nerve growth factor (NGF), the MSCs showed the development of numerous neurite outgrowths. These were, however, not readily observed in two-dimensional culture without the use of NGF. Immunofluorescence staining, western blot and fluorescence-activated cell sorting analyses demonstrated that a large population of cells was positive for NeuN and glial fibrillary acidic protein, which are specific to neuronal cells, when cultured in the three-dimensional collagen gel. The dependence of the neuronal differentiation of MSCs on the adhesive proteins containing three-dimensional gel matrices is considered to be closely related to focal adhesion kinase (FAK) activation through integrin receptor binding, as revealed by an experiment showing no neuronal outgrowth in the FAK-knockdown cells and stimulation of integrin ?1 gene. The results provided herein suggest the potential role of three-dimensional collagen-based gel matrices combined with adhesive proteins in the neuronal differentiation of MSCs, even without the use of chemical differentiation factors. Furthermore, these findings suggest that three-dimensional gel matrices might be useful as nerve-regenerative scaffolds. PMID:21247946

Lee, Jae Ho; Yu, Hye-Sun; Lee, Gil-Su; Ji, Aeri; Hyun, Jung Keun; Kim, Hae-Won

2011-01-01

200

Lymphocyte adhesion molecule ligands and extracellular matrix proteins in gliomas and normal brain: expression of VCAM-1 in gliomas  

Microsoft Academic Search

To identify antigenic differences between gliomas and normal brain, we have immunohistochemically studied the expression\\u000a of lymphocyte adhesion molecules (ICAM-1, ICAM-2, ICAM-3, VCAM-1, E-selectin and CD58), epidermal growth factor receptor (EGFR)\\u000a and extracellular matrix proteins (collagen IV, fibronectin, laminin, merosin, tenascin and vitronectin) in these tissues.\\u000a Gliomas expressed high levels of ICAM-1, CD58 (LFA-3), EGFR, tenascin and vitronectin, whereas only

Anna Mäenpää; Panu E. Kovanen; Anders Paetau; Juha Jääskeläinen; Tuomo Timonen

1997-01-01

201

A role for the protein tyrosine phosphatase CD45 in macrophage adhesion through the regulation of paxillin degradation.  

PubMed

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. PMID:23936270

St-Pierre, Joëlle; Ostergaard, Hanne L

2013-01-01

202

Members of the Pmp protein family of Chlamydia pneumoniae mediate adhesion to human cells via short repetitive peptide motifs  

PubMed Central

Chlamydiae sp. are obligate intracellular pathogens that cause a variety of diseases in humans. Adhesion of the infectious elementary body to the eukaryotic host cell is a pivotal step in chlamydial pathogenesis. Here we describe the characterization of members of the polymorphic membrane protein family (Pmp), the largest protein family (with up to 21 members) unique to Chlamydiaceae. We show that yeast cells displaying Pmp6, Pmp20 or Pmp21 on their surfaces, or beads coated with the recombinant proteins, adhere to human epithelial cells. A hallmark of the Pmp protein family is the presence of multiple repeats of the tetrapeptide motifs FxxN and GGA(I, L, V) and deletion analysis shows that at least two copies of these motifs are needed for adhesion. Importantly, pre-treatment of human cells with recombinant Pmp6, Pmp20 or Pmp21 protein reduces infectivity upon subsequent challenge with Chlamydia pneumoniae and correlates with diminished attachment of Chlamydiae to target cells. Antibodies specific for Pmp21 can neutralize infection in vitro. Finally, a combination of two different Pmp proteins in infection blockage experiments shows additive effects, possibly suggesting similar functions. Our findings imply that Pmp6, Pmp20 and Pmp21 act as adhesins, are vital during infection and thus represent promising vaccine candidates. PMID:21062373

Mölleken, Katja; Schmidt, Eleni; Hegemann, Johannes H

2010-01-01

203

Focal adhesion proteins connect IgE receptors to the cytoskeleton as revealed by micropatterned ligand arrays  

PubMed Central

Patterned surfaces that present specific ligands in spatially defined arrays are used to examine structural linkages between clustered IgE receptors (IgE-Fc?RI) and the cytoskeleton in rat basophilic leukemia (RBL) mast cells. We showed with fluorescence microscopy that cytoskeletal F-actin concentrates in the same regions as cell surface IgE-Fc?RI that bind to the micrometer-size patterned ligands. However, the proteins mediating these cytoskeletal connections and their functional relevance were not known. We now show that whereas the adaptor proteins ezrin and moesin do not detectably concentrate with the array of clustered IgE-Fc?RI, focal adhesion proteins vinculin, paxillin, and talin, which are known to link F-actin with integrins, accumulate in these regions on the same time scale as F-actin. Moreover, colocalization of these focal adhesion proteins with clustered IgE-Fc?RI is enhanced after addition of fibronectin-RGD peptides. Significantly, the most prominent rat basophilic leukemia cell integrin (?5) avoids the patterned regions occupied by the ligands and associates preferentially with exposed regions of the silicon substrate. Thus, spatial separation provided by the patterned surface reveals that particular focal adhesion proteins, which connect to the actin cytoskeleton, associate with ligand-cross-linked IgE-Fc?RI, independently of integrins. We investigated the functional role of one of these proteins, paxillin, in IgE-Fc?RI-mediated signaling by using small interfering RNA. From these results, we determine that paxillin reduces stimulated phosphorylation of the Fc?RI ? subunit but enhances stimulated Ca2+ release from intracellular stores. The results suggest that paxillin associated with clustered IgE-Fc?RI has a net positive effect on Fc?RI signaling. PMID:19004813

Torres, Alexis J.; Vasudevan, Lavanya; Holowka, David; Baird, Barbara A.

2008-01-01

204

Negative staining and immunoelectron microscopy of adhesion-deficient mutants of Streptococcus salivarius reveal that the adhesive protein antigens are separate classes of cell surface fibril.  

PubMed Central

The subcellular distribution of the cell wall-associated protein antigens of Streptococcus salivarius HB, which are involved in specific adhesive properties of the cells, was studied. Mutants which had lost the adhesive properties and lacked the antigens at the cell surface were compared with the parent strain. Immunoelectron microscopy of cryosections of cells labeled with affinity-purified, specific antisera and colloidal gold-protein A complexes was used to locate the antigens. Antigen C (AgC), a glycoprotein involved in attachment to host surfaces, was mainly located in the fibrillar layer outside the cell wall. A smaller amount of label was also found throughout the cytoplasmic area in the form of small clusters of gold particles, which suggests a macromolecular association. Mutant HB-7, which lacks the wall-associated AgC, accumulated AgC reactivity intracellularly. Intracellular AgC was often found associated with isolated areas of increased electron density, but sometimes seemed to fill the entire interior of the cell. Antigen B (AgB), a protein responsible for interbacterial coaggregation, was also located in the fibrillar layer, although its distribution differed from that of the wall-associated AgC since AgB was found predominantly in the peripheral areas. A very small amount of label was also found in the cytoplasmic area as discrete gold particles. Mutant HB-V5, which lacks wall-associated AgB, was not labeled in the fibrillar coat, but showed the same weak intracellular label as the parent strain. Immunolabeling with serum against AgD, another wall-associated protein but of unknown function, demonstrated its presence in the fibrillar layer of strain HB. Negatively stained preparations of whole cells of wild-type S. salivarius and mutants that had lost wall-associated AgB or AgC revealed that two classes of short fibrils are carried on the cell surface at the same time. AgB and AgC are probably located on separate classes of short, protease-sensitive fibrils 91 and 72 nm in length, respectively. A third class of only very sparsely distributed short fibrils (63 nm) was observed on mutant HB-V51, which lacks both wall-associated AgB and AgC antigens. The identity of these fibrils and whether they are present on the wild type are not clear. The function of long, protease-resistant fibrils of 178 nm, which are also present on the wild-type strain, remains unknown. Images PMID:2419308

Weerkamp, A H; Handley, P S; Baars, A; Slot, J W

1986-01-01

205

TM9/Phg1 and SadA proteins control surface expression and stability of SibA adhesion molecules in Dictyostelium  

PubMed Central

TM9 proteins form a family of conserved proteins with nine transmembrane domains essential for cellular adhesion in many biological systems, but their exact role in this process remains unknown. In this study, we found that genetic inactivation of the TM9 protein Phg1A dramatically decreases the surface levels of the SibA adhesion molecule in Dictyostelium amoebae. This is due to a decrease in sibA mRNA levels, in SibA protein stability, and in SibA targeting to the cell surface. A similar phenotype was observed in cells devoid of SadA, a protein that does not belong to the TM9 family but also exhibits nine transmembrane domains and is essential for cellular adhesion. A contact site A (csA)-SibA chimeric protein comprising only the transmembrane and cytosolic domains of SibA and the extracellular domain of the Dictyostelium surface protein csA also showed reduced stability and relocalization to endocytic compartments in phg1A knockout cells. These results indicate that TM9 proteins participate in cell adhesion by controlling the levels of adhesion proteins present at the cell surface. PMID:22219373

Froquet, Romain; le Coadic, Marion; Perrin, Jackie; Cherix, Nathalie; Cornillon, Sophie; Cosson, Pierre

2012-01-01

206

Activated PTHLH Coupling Feedback Phosphoinositide to G-Protein Receptor Signal-Induced Cell Adhesion Network in Human Hepatocellular Carcinoma by Systems-Theoretic Analysis  

PubMed Central

Studies were done on analysis of biological processes in the same high expression (fold change ?2) activated PTHLH feedback-mediated cell adhesion gene ontology (GO) network of human hepatocellular carcinoma (HCC) compared with the corresponding low expression activated GO network of no-tumor hepatitis/cirrhotic tissues (HBV or HCV infection). Activated PTHLH feedback-mediated cell adhesion network consisted of anaphase-promoting complex-dependent proteasomal ubiquitin-dependent protein catabolism, cell adhesion, cell differentiation, cell-cell signaling, G-protein-coupled receptor protein signaling pathway, intracellular transport, metabolism, phosphoinositide-mediated signaling, positive regulation of transcription, regulation of cyclin-dependent protein kinase activity, regulation of transcription, signal transduction, transcription, and transport in HCC. We proposed activated PTHLH coupling feedback phosphoinositide to G-protein receptor signal-induced cell adhesion network. Our hypothesis was verified by the different activated PTHLH feedback-mediated cell adhesion GO network of HCC compared with the corresponding inhibited GO network of no-tumor hepatitis/cirrhotic tissues, or the same compared with the corresponding inhibited GO network of HCC. Activated PTHLH coupling feedback phosphoinositide to G-protein receptor signal-induced cell adhesion network included BUB1B, GNG10, PTHR2, GNAZ, RFC4, UBE2C, NRXN3, BAP1, PVRL2, TROAP, and VCAN in HCC from GEO dataset using gene regulatory network inference method and our programming. PMID:22997493

Wang, Lin; Huang, Juxiang; Jiang, Minghu; Lin, Hong; Qi, Lianxiu; Diao, Haizhen

2012-01-01

207

Localization of vascular adhesion protein-1 (VAP-1) in the human eye.  

PubMed

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 therefore investigated by immunohistochemistry. Five micrometer thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs against VAP-1 (5 microg/ml), smooth muscle actin (1 microg/ml), CD31 or isotype-matched IgG at 4 degrees C. Subsequently, a secondary mAb was used for 30 min 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 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 colocalized 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 nearly 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. PMID:19761765

Almulki, Lama; Noda, Kousuke; Nakao, Shintaro; Hisatomi, Toshio; Thomas, Kennard L; Hafezi-Moghadam, Ali

2010-01-01

208

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. PMID:21737458

Heuts, Dominic P. H. M.; Gummadova, Jennet O.; Pang, Jiayun; Rigby, Stephen E. J.; Scrutton, Nigel S.

2011-01-01

209

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. PMID:14638776

Winter, Linda E.; Barenkamp, Stephen J.

2003-01-01

210

Three intrinsically unstructured mussel adhesive proteins, mfp-1, mfp-2, and mfp-3: Analysis by circular dichroism  

PubMed Central

Mussel foot proteins (mfps) mediate fouling by the byssal holdfast and have been extensively investigated as models for versatile polymer-mediated underwater adhesion and coatings. However, insights into the structural properties of mfps have lagged far behind the nanomechanical advances, owing in part to the inability of these proteins to crystallize as well as their limited solubility. Here, solution secondary structures of mfp-1, mfp-2, and mfp-3, localized in the mussel byssal cuticle, adhesive plaque, and plaque–substratum interface, respectively, were investigated using circular dichroism. All three have significant extended coil solution structure, but two, mfp-1 and mfp-2, appear to have punctuated regions of structure separated by unstructured domains. Apart from its punctuated distribution, the structure in mfp-1 resembles other structural proteins such as collagen and plant cell-wall proteins with prominent polyproline II helical structure. As in collagen, PP II structure of mfp-1 is incrementally disrupted by increasing the temperature and by raising pH. However, no recognizable change in mfp-1's PP II structure was evident with the addition with Ca2+ and Fe3+. In contrast, mfp-2 exhibits Ca2+- and disulfide-stabilized epidermal growth factor-like domains separated by unstructured sequence. Mfp-2 showed calcium-binding ability. Bound calcium in mfp-2 was not removed by chelation at pH 5.5, but it was released upon reduction of disulfide bonds. Mfp-3, in contrast, appears to consist largely of unstructured extended coils. PMID:22915553

Hwang, Dong Soo; Waite, J Herbert

2012-01-01

211

Expression of so-called adhesion proteins and DNA cytometric analysis in malignant parotid tumours as predictors of clinical outcome.  

PubMed

Tumours of the salivary glands are rare, and account for only 0.5-1% of all tumours. We have analysed the cytoarchitectural structure of such tumours by studying 3 binding proteins that act on different parts of the glandular epithelial architecture: e-cadherin, laminin, and CD44. We analysed the DNA using image cytometry to evaluate ploidy, S-phase, and 5c exceeding rate, and to compare the biological aggressiveness of the proteins. Our goal was to correlate the degree of structural integrity and the histological grade of the injury, and to try to find new biological factors that would help to predict the evolution of disease in the salivary glands. The immunoexpression pattern of the so-called adhesion proteins of the salivary glands, when combined, yields important data about the aggressiveness of malignant neoplasms, and provides useful tools with which to predict the biological evolution of malignant lesions. PMID:24309001

Azúa-Romeo, J; Saura, D; Guerrero, M; Turner, M; Saura, E

2014-02-01

212

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

2009-03-01

213

Adsorption of Proteins to Thin-Films of PDMS and Its Effect on the Adhesion of Human Endothelial Cells  

PubMed Central

This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine serum albumin) under different conditions. The information collected from the protein adsorption studies was then used to investigate the adhesion of human dermal microvascular endothelial cells. The results of these studies suggest that these films can be used to model the surface properties of microdevices fabricated with commercial PDMS. Moreover, the paper provides guidelines to efficiently attach cells in BioMEMS devices. PMID:25068038

Chumbimuni-Torres, Karin Y.; Coronado, Ramon E.; Mfuh, Adelphe M.; Castro-Guerrero, Carlos; Silva, Maria Fernanda; Negrete, George R.; Bizios, Rena; Garcia, Carlos D.

2014-01-01

214

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

2013-04-01

215

A Biologically Active Sequence of the Laminin ?2 Large Globular 1 Domain Promotes Cell Adhesion through Syndecan-1 by Inducing Phosphorylation and Membrane Localization of Protein Kinase C?*  

PubMed Central

Laminin-2 promotes basement membrane assembly and peripheral myelinogenesis; however, a receptor-binding motif within laminin-2 and the downstream signaling pathways for motif-mediated cell adhesion have not been fully established. The human laminin-2 ?2 chain cDNAs cloned from human keratinocytes and fibroblasts correspond to the laminin ?2 chain variant sequence from the human brain. Individually expressed recombinant large globular (LG) 1 protein promotes cell adhesion and has heparin binding activities. Studies with synthetic peptides delineate the DLTIDDSYWYRI motif (Ln2-P3) within the LG1 as a major site for both heparin and cell binding. Cell adhesion to LG1 and Ln2-P3 is inhibited by treatment of heparitinase I and chondroitinase ABC. Syndecan-1 from PC12 cells binds to LG1 and Ln2-P3 and colocalizes with both molecules. Suppression of syndecan-1 with RNA interference inhibits cell adhesion to LG1 and Ln2-P3. The binding of syndecan-1 with LG1 and Ln2-P3 induces the recruitment of protein kinase C? (PKC?) into the membrane and stimulates its tyrosine phosphorylation. A decrease in PKC? activity significantly reduces cell adhesion to LG1 and Ln2-P3. Taken together, these results indicate that the Ln2-P3 motif and LG1 domain, containing the motif, within the human laminin-2 ?2 chain are major ligands for syndecan-1, which mediates cell adhesion through the PKC? signaling pathway. PMID:19762914

Jung, Sung Youn; Kim, Jin-Man; Kang, Hyun Ki; Jang, Da Hyun; Min, Byung-Moo

2009-01-01

216

Mouse Vascular Adhesion Protein 1 Is a Sialoglycoprotein with Enzymatic Activity and Is Induced in Diabetic Insulitis  

PubMed Central

The continuous recirculation of lymphocytes requires an adequate expression and function of the molecules mediating the cellular interactions between endothelium and lymphocytes. Human vascular adhesion protein 1 (hVAP-1) is an endothelial cell adhesion molecule that mediates the binding of lymphocytes to venules in peripheral lymph nodes as well as at sites of inflammation. Recently the mouse homologue of hVAP-1 has been cloned. It is a previously unknown molecule with a significant sequence identity to copper-containing amine oxidases. Besides the sequence, very little is known about the expression, structure, and function of mouse VAP-1 (mVAP-1). In this study we demonstrate that mVAP-1 is prominently expressed in endothelial and smooth muscle (but not in other types of muscle cells), as well as in adipocytes. mVAP-1 is a 220-kd homodimeric sialoglycoprotein that displays cell-type-specific differences in glycosylation. The expression of mVAP-1 is induced on inflammation in the vessels of the endocrine pancreas during the development of insulitis, and the up-regulation correlates with the extent of the lymphocytic infiltrate. In general, different mouse strains displayed very similar VAP-1 expression, but the small differences seen in liver and gut suggest that immunostimulation may modulate VAP-1 synthesis in extrapancreatic organs as well. Finally, we show that mVAP-1 has a monoamine oxidase activity against naturally occurring substrates, implying a role in the development of vasculopathies. These data show that mVAP-1 and hVAP-1 are very similar molecules that nevertheless have certain marked differences in expression, biochemical structure, and substrate specificity. Thus mVAP-1 is a novel inflammation-inducible mouse molecule that has a dual adhesive and enzymatic function. PMID:10550318

Bono, Petri; Jalkanen, Sirpa; Salmi, Marko

1999-01-01

217

The Yak1 protein kinase lies at the center of a regulatory cascade affecting adhesive growth and stress resistance in Saccharomyces cerevisiae.  

PubMed

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. PMID:21149646

Malcher, Mario; Schladebeck, Sarah; Mösch, Hans-Ulrich

2011-03-01

218

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. PMID:21149646

Malcher, Mario; Schladebeck, Sarah; Mösch, Hans-Ulrich

2011-01-01

219

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.

220

Denture Adhesives  

MedlinePLUS

... Multiple-Use Dental Dispenser Devices Dental Amalgam Denture Adhesives Background Zinc and Potential Risk Reports of Problems ... Wearers Reporting Problems to the FDA Background Denture adhesives are pastes, powders or adhesive pads that may ...

221

Lebecetin, a C-lectin protein from the venom of Macrovipera lebetina that inhibits platelet aggregation and adhesion of cancerous cells.  

PubMed

A novel C-lectin protein, lebecetin, was purified and characterized from the venom of Macrovipera lebetina. It is a disulfide-linked heterodimer of 15 and 16 kD. The subunits are homologous to each other and to the other snake venom proteins of the C-type (Ca(2+)-dependent) lectin superfamily. Lebecetin shows a potent inhibitory effect on whole blood and washed platelets induced by different agonists. It inhibits the agglutination of human fixed platelets in the presence of ristocetin. Lebecetin also interferes with the adhesion of IGR39 melanoma and HT29D4 adenocarcinoma cells. These two lines adhere to lebecetin used as matrix. Lebecetin is also able to strongly reduce IGR39 and HT29D4 cell adhesion to fibrinogen and laminin, but not to fibronectin and collagen types I and IV, respectively. Adhesion properties of lebecetin may thus involve integrin receptors. PMID:11910182

Sarray, S; Srairi, N; Luis, J; Marvaldi, J; El Ayeb, M; Marrakchi, N

2001-01-01

222

Demonstration of adhesion activity of the soluble Ig-domain protein C-CAM4 by attachment to the plasma membrane.  

PubMed

The carcinoembryonic antigen (CEA) family is a large group of proteins with immunoglobulin (Ig)-like structures. The membrane-associated CEA-family proteins have been shown to mediate intercellular adhesion. In addition to these membrane-associated proteins, several secreted CEA-like proteins, such as C-CAM4, PSG1b, and PSG11s, have also been identified. The functions of these soluble proteins are not clear because they cannot support intercellular adhesion like the membrane-associated proteins can. A fundamental question important for understanding the functions of these soluble proteins is whether they can interact in a homophilic fashion as do many of their membrane-associated homologues. We found that the homophilic interactions between these soluble proteins were too weak to be detected by solution binding assays. This is not unexpected because interactions between adhesion molecules are usually transient and weak to allow for control of association and dissociation. By expressing these soluble CEA-family proteins, C-CAM4, PSG1b, and PSG11s, as membrane-anchored forms, we showed that C-CAM4 could mediate intercellular adhesion, whereas PSG1b and PSG11s, despite their 52% identity to C-CAM4, could not. These results suggest that C-CAM4, but not PSG1b and PSG11s, can probably form homodimers. Thus, these secretory CEA-family members most likely have different interaction mechanisms, i.e., C-CAM4 might function as dimers, while PSGs might function as monomers. PMID:9571177

Lin, S H; Cheng, H; Earley, K; Luo, W; Chou, J

1998-04-17

223

Matrix Metalloproteinase 9 (MMP-9)-dependent Processing of ?ig-h3 Protein Regulates Cell Migration, Invasion, and Adhesion*  

PubMed Central

Cell migration is critically involved in inflammation, cancer, and development. In this study, transforming growth factor-?-induced protein (?ig-h3) was identified as a substrate of matrix metalloproteinase-9 (MMP-9) by site-directed mutagenesis. ?ig-h3 has two cleavage sites with the consensus sequence Pro-Xaa-Xaa-Hy-(Ser/Thr) (Hy is a hydrophobic amino acid) (PGSFT beginning at amino acid 135 and PPMGT beginning at amino acid 501). Using recombinant human ?ig-h3 and MMP-9, ?ig-h3 from ?ig-h3-transfected HEK293F cells, and MMP-9 from MMP-9-transfected HEK293F cells, human macrophages, and neutrophils, we found that MMP-9 proteolytically cleaves ?ig-h3. Cleavage leads to the loss of its adhesive property and its release from extracellular matrix proteins, collagen IV, and fibronectin. Spheroids formed by increased cell-cell interactions were observed in ?ig-h3-transfected HEK293F cells but not in vehicle-transfected HEK293F cells. In human glioma U87MG cells, MMP-9 constitutive overexpression resulted in endogenous ?ig-h3 cleavage. ?ig-h3 cleavage by MMP-9 led to increased cell invasion, and ?ig-h3 knockdown also resulted in increased cell invasion. The ?ig-h3 fragment cleaved by MMP-9 could bind to the surface of macrophages, and it may play a role as a peptide chemoattractant by inducing macrophage migration via focal adhesion kinase/Src-mediated signal activation. Thus, intact ?ig-h3 is responsible for cell migration inhibition, cell-cell contact, and cell-extracellular matrix interaction. Experimental evidence indicates that MMP-9-cleaved ?ig-h3 plays a role in MMP-9-mediated tumor cell and macrophage migration. PMID:23019342

Kim, Yeon Hyang; Kwon, Hyung-Joo; Kim, Doo-Sik

2012-01-01

224

Comparison of adhesive properties of water- and phosphate-buffer-washed cottonseed meals with cottonseed protein isolate on bonding maple and poplar veneers  

Technology Transfer Automated Retrieval System (TEKTRAN)

Water- and phosphate buffer (35 mM Na2HPO4/NaH2PO4, pH 7.5)-washed cottonseed meals (abbreviated as WCM and BCM, respectively) could be low-cost and environmentally friendly protein-based adhesives as their preparation does not involve corrosive alkali and acid solutions that are needed for cottonse...

225

Aggrecan and link protein affect cell adhesion to culture plates and to type II collagen  

Microsoft Academic Search

Cartilage is a hypocellular tissue in which a balance of matrix molecules, especially aggrecan and link protein, play a critical role in maintaining structural integrity. To study the role of aggrecan and link protein in mediating cell activities, we have stably expressed them in NIH\\/3T3 fibroblasts and observed the effect on cell-substratum interactions. Overexpression of either protein destabilized the cell-substratum

Burton B. Yang; Yaou Zhang; Liu Cao; Bing L. Yang

1998-01-01

226

Protein adsorption and cell adhesion on nanoscale bioactive coatings formed from poly(ethylene glycol) and albumin microgels  

PubMed Central

Late-term thrombosis on drug-eluting stents is an emerging problem that might be addressed using extremely thin, biologically-active hydrogel coatings. We report a dip-coating strategy to covalently link poly(ethylene glycol) (PEG) to substrates, producing coatings with protein-resistant layer with a thickness of approximately 75 nm. Atomic force microscopy in buffered water revealed the presence of coalesced spheres of various sizes but with diameters less than about 100 nm. Microgel-coated glass or poly(ethylene terephthalate) exhibited reduced protein adsorption and cell adhesion. Cellular interactions with the surface could be controlled by using different proteins to cap unreacted vinylsulfone groups within the coating. PMID:18771802

Scott, Evan A.; Nichols, Michael D.; Cordova, Lee H.; George, Brandon J.; Jun, Young-Shin; Elbert, Donald L.

2008-01-01

227

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

228

Structure, Expression, and Function of a Novel Intercalated Disc Protein, Xin  

PubMed Central

Xin was first cloned using differential mRNA display from the developing chicken heart. Chick Xin (cXin) participates in a BMP-Nkx2.5-MEF2C pathway to regulating cardiac morphogenesis. Through subsequent EST database searches and cDNA cloning, two mouse Xin genes, mXin? and mXin? were identified and cloned. The human homologue of mXin? (named Cmya1) was mapped to chromosome 3p21.2-p21.3 by radiation hybrid analysis and recently to 3p22.2 by DNA sequencing, which is near the loci for a dilated cardiomyopathy with conduction defect-2 and arrhythmogenic right ventricular dysplasia-5. The predicted human homologue of mXin? (named Cmya3) was mapped to chromosome 2q24.3 by DNA sequencing. Predicted Xin proteins all contain a novel 16-amino acid repeating unit (Xin repeat), a putative DNA binding domain and nuclear localization signal, as well as a proline-rich region. All three Xin genes from chick and mouse have a similar tissue expression profile, which is restricted to striated muscle. The expression of mXin? in Nkx2.5 or MEF2C knockout mouse embryos was drastically reduced, suggesting that mXin? is a downstream target of the Nkx2.5 and MEF2C transcription factors. On the other hand, the expression of mXin was up-regulated when mice were subjected to pressure overload-induced cardiac hypertrophy. Xin protein co-localizes with N-cadherin and ?-catenin throughout mouse embryogenesis and into adulthood. Furthermore, mXin? appears to interact directly with ?-catenin. The Xin repeats bind to actin filaments and may also organize microfilaments into networks. These results may suggest that Xin acts by integrating adhesion, by organizing actin filament arrangement at the insertion sites, and by regulating Wnt/?-catenin-and N-cadherin-mediated signaling pathways required for cardiac development and cardiac function. PMID:16708114

Jung-Ching Lin, Jim; Gustafson-Wagner, Elisabeth A.; Sinn, Haley W.; Choi, Sunju; Jaacks, Shannon M.; Wang, Da-Zhi; Evans, Sylvia; Li-Chun Lin, Jenny

2005-01-01

229

Biologically engineered protein-graft-poly(ethylene glycol) hydrogels: A cell-adhesive and plasmin-degradable biosynthetic material for tissue repair  

NASA Astrophysics Data System (ADS)

The goal of the research presented in this dissertation was to create a biomimetic artificial material that exhibits functions of extracellular matrix relevant for improved nerve regeneration. Neural adhesion peptides were photoimmobilized on highly crosslinked poly(ethylene glycol)-based substrates that were otherwise non-adhesive. Neurons adhered in two-dimensional patterns for eleven hours, but no neurites extended. To enable neurite extension and nerve regeneration in three dimensions, and to address the need for specifically cell adhesive and cell degradable materials for clinical applications in tissue repair in general, an artificial protein was recombinantly expressed and purified that consisted of a repeating amino acid sequence based on fibrinogen and anti-thrombin III. The recombinant protein contained integrin-binding RGD sites, plasmin degradation sites, heparin binding sites, and six thiol-containing cysteine residues as grafting sites for poly(ethylene glycol) diacrylate via Michael-type conjugate addition. The resulting protein-graft-poly(ethylene glycol)acrylates were crosslinked by photopolymerization to form hydrogels. Although three-dimensional, RGD mediated and serine protease-dependent ingrowth of human fibroblasts into protein-graft-poly(ethylene glycol) hydrogels occurred, only surface neurite outgrowth was observed from chick dorsal root ganglia. Axonal outgrowth depended on the concentration of matrix-bound heparin, suggesting that improved mechanical strength of the hydrogels and possible immobilization of neuroactive factors due to the presence of heparin promoted neurite outgrowth. Together, the above results show that specific biological functions can be harnessed by protein-graft-poly(ethylene glycol) hydrogels to serve as matrices for tissue repair and regeneration. In particular, the two design objectives, specific cell adhesion and degradability by cell-associated proteases, were fulfilled by the material. In the future, this and similar artificial protein-graft-poly(ethylene glycol) materials with varying protein elements for improved wound healing might serve as biosynthetic implant materials or wound dressings that degrade in synchrony with the formation of a variety of target tissues.

Halstenberg, Sven

2002-01-01

230

[Influence of different adhesive composition on sporulation and protein synthesis by Bacillus thuringiensis collection strains].  

PubMed

The influence of different sticky-gene composition on sporulation and protein synthesis by B. thuringiensis collection strains has been investigated. It has been detemined that the most effective according this characteristics were B. thuringiensis collection strains 0293 and 98. It has been shown that the best on protein synthesis processes and sporulation by investigated B. thuringiensis strains influences adding to the culture medium sticky-gene compositions A and E in a concentration of from 10 to 15%. PMID:25434213

Krut', V V; Dankevych, L A; Votselko, S K; Patyka, V P

2014-01-01

231

Adsorption and adhesion of common serum proteins to nanotextured gallium nitride.  

PubMed

As the broader effort towards device and material miniaturization progresses in all fields, it becomes increasingly important to understand the implications of working with functional structures that approach the size scale of molecules, particularly when considering biological systems. It is well known that thin films and nanostructures feature different optical, electrical, and mechanical properties from their bulk composites; however, interactions taking place at the interface between nanomaterials and their surroundings are less understood. Here, we explore interactions between common serum proteins - serum albumin, fibrinogen, and immunoglobulin G - and a nanotextured gallium nitride surface. Atomic force microscopy with a carboxyl-terminated colloid tip is used to probe the 'activity' of proteins adsorbed onto the surface, including both the accessibility of the terminal amine to the tip as well as the potential for protein extension. By evaluating the frequency of tip-protein interactions, we can establish differences in protein behaviour on the basis of both the surface roughness as well as morphology, providing an assessment of the role of surface texture in dictating protein-surface interactions. Unidirectional surface features - either the half-unit cell steppes of as-grown GaN or those produced by mechanical polishing - appear to promote protein accessibility, with a higher frequency of protein extension events taking place on these surfaces when compared with less ordered surface features. Development of a full understanding of the factors influencing surface-biomolecule interactions can pave the way for specific surface modification to tailor the bio-material interface, offering a new path for device optimization. PMID:25564044

Bain, Lauren E; Hoffmann, Marc P; Bryan, Isaac; Collazo, Ramón; Ivanisevic, Albena

2015-01-28

232

Homology modeling of an immunoglobulin-like domain in the Saccharomyces cerevisiae adhesion protein alpha-agglutinin.  

PubMed

The Saccharomyces cerevisiae adhesion protein alpha-agglutinin is expressed by cells of alpha mating type. On the basis of sequence similarities, alpha-agglutinin has been proposed to contain variable-type immunoglobulin-like (IgV) domains. The low level of sequence similarity to IgV domains of known structure made homology modeling using standard sequence-based alignment algorithms impossible. We have therefore developed a secondary structure-based method that allowed homology modeling of alpha-aggulutinin domain III, the domain most similar to IgV domains. The model was assessed and where necessary refined to accommodate information obtained by biochemical and molecular genetic approaches, including the positions of a disulfide bond, glycosylation sites, and proteolytic sites. The model successfully predicted surface exposure of glycosylation and proteolytic sites, as well as identifying residues essential for binding activity. One side of the domain was predicted to be covered by carbohydrate residues. Surface accessibility and volume packing analyses showed that the regions of the model that have greatest sequence dissimilarity from the IgV consensus sequence are poorly structured in the biophysical sense. Nonetheless, the utility of the model suggests that these alignment and testing techniques should be of general use for building and testing of models of proteins that share limited sequence similarity with known structures. PMID:8535254

Lipke, P N; Chen, M H; de Nobel, H; Kurjan, J; Kahn, P C

1995-10-01

233

Homology modeling of an immunoglobulin-like domain in the Saccharomyces cerevisiae adhesion protein alpha-agglutinin.  

PubMed Central

The Saccharomyces cerevisiae adhesion protein alpha-agglutinin is expressed by cells of alpha mating type. On the basis of sequence similarities, alpha-agglutinin has been proposed to contain variable-type immunoglobulin-like (IgV) domains. The low level of sequence similarity to IgV domains of known structure made homology modeling using standard sequence-based alignment algorithms impossible. We have therefore developed a secondary structure-based method that allowed homology modeling of alpha-aggulutinin domain III, the domain most similar to IgV domains. The model was assessed and where necessary refined to accommodate information obtained by biochemical and molecular genetic approaches, including the positions of a disulfide bond, glycosylation sites, and proteolytic sites. The model successfully predicted surface exposure of glycosylation and proteolytic sites, as well as identifying residues essential for binding activity. One side of the domain was predicted to be covered by carbohydrate residues. Surface accessibility and volume packing analyses showed that the regions of the model that have greatest sequence dissimilarity from the IgV consensus sequence are poorly structured in the biophysical sense. Nonetheless, the utility of the model suggests that these alignment and testing techniques should be of general use for building and testing of models of proteins that share limited sequence similarity with known structures. PMID:8535254

Lipke, P. N.; Chen, M. H.; de Nobel, H.; Kurjan, J.; Kahn, P. C.

1995-01-01

234

3,4-Methylenedioxy-?-nitrostyrene inhibits adhesion and migration of human triple-negative breast cancer cells by suppressing ?1 integrin function and surface protein disulfide isomerase.  

PubMed

Triple negative breast cancer (TNBC) exhibits an aggressive clinical course by high metastatic potential. It is known that integrin-mediated cell adhesion and migration are important for cancer metastasis. In the present study, a synthetic compound, 3, 4-methyenedioxy-?-nitrostyrene (MNS), significantly inhibited adhesion of TNBC cell lines to different extracellular matrix (ECM) components. The antimetastatic capacity of MNS was also observed through reducing TNBC cells migration and invasion without affecting cell viability. Confocal microscopy revealed that MNS disrupted the formation of focal adhesion complex and actin stress fiber networks. Consistent with this finding, MNS inhibited phosphorylation of focal adhesion kinase (FAK) and paxillin as detected by Western blot analysis. In exploring the underlying mechanism, we found that MNS inhibited phosphorylation of FAK as a result of reducing ?1 integrin activation and clustering. A cell-impermeable dithiol reagent, 2, 3-dimercaptopropane-1-sulfonic acid abrogated all of MNS's actions, indicating that MNS may react with thiol groups of cell surface proteins that are involved in regulation of ?1 integrin function as well as cell adhesion and migration. Cell surface protein disulfide isomerase (PDI) has been reported to be essential for the affinity modulation of ? integrins. We also demonstrated that MNS inhibited PDI activity both in a pure enzyme system and in intact cancer cells. Taken together, our results suggest that MNS inhibits in vitro metastatic properties of TNBC cells through suppression of ?1 integrin activation and focal adhesion signaling. Moreover, inhibition of surface PDI may contribute, at least in part, to the actions of MNS. These results suggest that MNS has a potential to be developed as an anticancer agent for treatment of TNBC. PMID:25593085

Chen, I-Hua; Chang, Fang-Rong; Wu, Yang-Chang; Kung, Po-Hsiung; Wu, Chin-Chung

2015-03-01

235

Atmospheric pressure plasma polymers for tuned QCM detection of protein adhesion.  

PubMed

Our efforts have been concentrated in preparing plasma polymeric thin layers at atmospheric pressure grown on Quartz Crystal Microbalance-QCM electrodes for which the non-specific absorption of proteins can be efficiently modulated, tuned and used for QCM biosensing and quantification. Plasma polymerization reaction at atmospheric pressure has been used as a simple and viable method for the preparation of QCM bioactive surfaces, featuring variable protein binding properties. Polyethyleneglycol (ppEG), polystyrene (ppST) and poly(ethyleneglycol-styrene) (ppST-EG) thin-layers have been grown on QCM electrodes. These layers were characterized by Atomic Force Microscopy (AFM), Contact angle measurements, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The plasma ppST QCM electrodes present a higher adsorption of Concanavalin A (ConA) and Bovine Serum Albumin (BSA) proteins when compared with the commercial coated polystyrene (ppST) ones. The minimum adsorption was found for ppEG, surface, known by their protein anti-fouling properties. The amount of adsorbed proteins can be tuned by the introduction of PEG precursors in the plasma discharge during the preparation of ppST polymers. PMID:24140830

Rusu, G B; Asandulesa, M; Topala, I; Pohoata, V; Dumitrascu, N; Barboiu, M

2014-03-15

236

The Neuroplastin Adhesion Molecules Are Accessory Proteins That Chaperone the Monocarboxylate Transporter MCT2 to the Neuronal Cell Surface  

PubMed Central

Background The neuroplastins np65 and np55 are two synapse-enriched immunoglobulin (Ig) superfamily adhesion molecules that contain 3 and 2 Ig domains respectively. Np65 is implicated in long term, activity dependent synaptic plasticity, including LTP. Np65 regulates the surface expression of GluR1 receptor subunits and the localisation of GABAA receptor subtypes in hippocampal neurones. The brain is dependent not only on glucose but on monocarboxylates as sources of energy. The. monocarboxylate transporters (MCTs) 1–4 are responsible for the rapid proton-linked translocation of monocarboxylates including pyruvate and lactate across the plasma membrane and require association with either embigin or basigin, proteins closely related to neuroplastin, for plasma membrane expression and activity. MCT2 plays a key role in providing lactate as an energy source to neurons. Methodology/Findings Here we use co-transfection of neuroplastins and monocarboxylate transporters into COS-7 cells to demonstrate that neuroplastins can act as ancillary proteins for MCT2. We also show that Xenopus laevis oocytes contain endogenous neuroplastin and its knockdown with antisense RNA reduces the surface expression of MCT2 and associated lactate transport. Immunocytochemical studies show that MCT2 and the neuroplastins are co-localised in rat cerebellum. Strikingly neuroplastin and MCT2 are enriched in the same parasagittal zebrin II-negative stripes. Conclusions These data strongly suggest that neuroplastins act as key ancillary proteins for MCT2 cell surface localisation and activity in some neuronal populations, thus playing an important role in facilitating the uptake of lactate for use as a respiratory fuel. PMID:24260123

Wilson, Marieangela C.; Kraus, Michaela; Marzban, Hassan; Sarna, Justyna R.; Wang, Yisong; Hawkes, Richard; Halestrap, Andrew P.; Beesley, Philip W.

2013-01-01

237

Adhesion of Trypanosoma cruzi Trypomastigotes to Fibronectin or Laminin Modifies Tubulin and Paraflagellar Rod Protein Phosphorylation  

PubMed Central

Background The unicellular parasite Trypanosoma cruzi is the causative agent of Chaga? disease in humans. Adherence of the infective stage to elements of the extracellular matrix (ECM), as laminin and fibronectin, is an essential step in host cell invasion. Although members of the gp85/TS, as Tc85, were identified as laminin and fibronectin ligands, the signaling events triggered on the parasite upon binding to these molecules are largely unexplored. Methodology/Principal Findings Viable infective parasites were incubated with laminin, fibronectin or bovine serum albumin for different periods of time and the proteins were separated by bidimensional gels. The phosphoproteins were envisaged by specific staining and the spots showing phosphorylation levels significantly different from the control were excised and identified by MS/MS. The results of interest were confirmed by immunoblotting or immunoprecipitation and the localization of proteins in the parasite was determined by immunofluorescence. Using a host cell-free system, our data indicate that the phosphorylation contents of T. cruzi proteins encompassing different cellular functions are modified upon incubation of the parasite with fibronectin or laminin. Conclusions/Significance Herein it is shown, for the first time, that paraflagellar rod proteins and ?-tubulin, major structural elements of the parasite cytoskeleton, are predominantly dephosphorylated during the process, probably involving the ERK1/2 pathway. It is well established that T. cruzi binds to ECM elements during the cell infection process. The fact that laminin and fibronectin induce predominantly dephosphorylation of the main cytoskeletal proteins of the parasite suggests a possible correlation between cytoskeletal modifications and the ability of the parasite to internalize into host cells. PMID:23056443

Mattos, Eliciane C.; Schumacher, Robert I.; Colli, Walter; Alves, Maria Julia M.

2012-01-01

238

Protein N-glycosylation in oral cancer: Dysregulated cellular networks among DPAGT1, E-cadherin adhesion and canonical Wnt signaling  

PubMed Central

N-Linked glycosylation (N-glycosylation) of proteins has long been associated with oncogenesis, but not until recently have the molecular mechanisms underlying this relationship begun to be unraveled. Here, we review studies describing how dysregulation of the N-glycosylation-regulating gene, DPAGT1, drives oral cancer. DPAGT1 encodes the first and rate-limiting enzyme in the assembly of the lipid-linked oligosaccharide precursor in the endoplasmic reticulum and thus mediates N-glycosylation of many cancer-related proteins. DPAGT1 controls N-glycosylation of E-cadherin, the major epithelial cell–cell adhesion receptor and a tumor suppressor, thereby affecting intercellular adhesion and cytoskeletal dynamics. DPAGT1 also regulates and is regulated by Wnt/?-catenin signaling, impacting the balance between proliferation and adhesion in homeostatic tissues. Thus, aberrant induction of DPAGT1 promotes a positive feedback network with Wnt/?-catenin that represses E-cadherin-based adhesion and drives tumorigenic phenotypes. Further, modification of receptor tyrosine kinases (RTKs) with N-glycans is known to control their surface presentation via the galectin lattice, and thus increased DPAGT1 expression likely contributes to abnormal activation of RTKs in oral cancer. Collectively, these studies suggest that dysregulation of the DPAGT1/Wnt/E-cadherin network underlies the etiology and pathogenesis of oral cancer. PMID:24742667

Varelas, Xaralabos; Bouchie, Meghan P; Kukuruzinska, Maria A

2014-01-01

239

Novel Modulator for Endothelial Adhesion Molecules Adipocyte-Derived Plasma Protein Adiponectin  

Microsoft Academic Search

Background—Among the many adipocyte-derived endocrine factors, we recently found an adipocyte-specific secretory protein, adiponectin, which was decreased in obesity. Although obesity is associated with increased cardiovascular mortality and morbidity, the molecular basis for the link between obesity and vascular disease has not been fully clarified. The present study investigated whether adiponectin could modulate endothelial function and relate to coronary disease.

Noriyuki Ouchi; Shinji Kihara; Yukio Arit; Kazuhisa Maeda; Hiroshi Kuriyama; Yoshihisa Okamoto; Kikuko Hott; Makoto Nishida; Masahiko Takahashi; Tadashi Nakamura; Shizuya Yamashita; Tohru Funahashi; Yuji Matsuzawa

240

The Campylobacter jejuni Cj0268c Protein Is Required for Adhesion and Invasion In Vitro  

PubMed Central

Adherence of Campylobacter jejuni to its particular host cells is mediated by several pathogen proteins. We screened a transposon-based mutant library of C. jejuni in order to identify clones with an invasion deficient phenotype towards Caco2 cells and detected a mutant with the transposon insertion in gene cj0268c. In vitro characterization of a generated non-random mutant, the mutant complemented with an intact copy of cj0268c and parental strain NCTC 11168 confirmed the relevance of Cj0268c in the invasion process, in particular regarding adherence to host cells. Whereas Cj0268c does not impact autoagglutination or motility of C. jejuni, heterologous expression in E. coli strain DH5? enhanced the potential of the complemented E. coli strain to adhere to Caco2 cells significantly and, thus, indicates that Cj0268c does not need to interact with other C. jejuni proteins to develop its adherence-mediating phenotype. Flow cytometric measurements of E. coli expressing Cj0268c indicate a localization of the protein in the periplasmic space with no access of its C-terminus to the bacterial surface. Since a respective knockout mutant possesses clearly reduced resistance to Triton X-100 treatment, Cj0268c contributes to the stability of the bacterial cell wall. Finally, we could show that the presence of cj0268c seems to be ubiquitous in isolates of C. jejuni and does not correlate with specific clonal groups regarding pathogenicity or pathogen metabolism. PMID:24303031

Tareen, A. Malik; Lüder, Carsten G. K.; Zautner, Andreas E.; Groß, Uwe; Heimesaat, Markus M.; Bereswill, Stefan; Lugert, Raimond

2013-01-01

241

Seafood delicacy makes great adhesive  

SciTech Connect

Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

Idaho National Laboratory - Frank Roberto, Heather Silverman

2008-03-26

242

Seafood delicacy makes great adhesive  

ScienceCinema

Technology from Mother Nature is often hard to beat, so Idaho National Laboratory scientistsgenetically analyzed the adhesive proteins produced by blue mussels, a seafood delicacy. Afterobtaining full-length DNA sequences encoding these proteins, reprod

Idaho National Laboratory - Frank Roberto, Heather Silverman

2010-01-08

243

A model for central synaptic junctional complex formation based on the differential adhesive specificities of the cadherins.  

PubMed

Cadherins control critical developmental events through well-documented homophilic interactions. In epithelia, they are hallmark constituents of junctions that mediate intercellular adhesion. Brain tissue expresses several cadherins, and we now show that two of these, neural (N)- and epithelial (E)-cadherin, are localized to synaptic complexes in mutually exclusive distributions. In cerebellum, N-cadherin is frequently found associated with synapses, some of which are perforated, and in hippocampus, N- and E-cadherin-containing synapses are found aligned along dendritic shafts within the stratum lucidum of CA3. We propose that the cadherins function as primary adhesive moieties between pre- and postsynaptic membranes in the synaptic complex. According to this model, once neurites have been guided to the vicinity of their cognate targets, it is the differential distribution of cadherins along the axonal and dendritic plasma membranes, and ultimately cadherin self-association, that "locks in" nascent synaptic connections. PMID:8816706

Fannon, A M; Colman, D R

1996-09-01

244

Lactobacillus Adhesion to Mucus  

PubMed Central

Mucus provides protective functions in the gastrointestinal tract and plays an important role in the adhesion of microorganisms to host surfaces. Mucin glycoproteins polymerize, forming a framework to which certain microbial populations can adhere, including probiotic Lactobacillus species. Numerous mechanisms for adhesion to mucus have been discovered in lactobacilli, including partially characterized mucus binding proteins. These mechanisms vary in importance with the in vitro models studied, which could significantly affect the perceived probiotic potential of the organisms. Understanding the nature of mucus-microbe interactions could be the key to elucidating the mechanisms of probiotic adhesion within the host. PMID:22254114

Tassell, Maxwell L. Van; Miller, Michael J.

2011-01-01

245

Adhesion Protein ApfA of Actinobacillus pleuropneumoniae Is Required for Pathogenesis and Is a Potential Target for Vaccine Development  

PubMed Central

Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia, which causes serious economic losses in the pig farming industry worldwide. Due to a lack of knowledge of its virulence factors and a lack of effective vaccines able to confer cross-serotype protection, it is difficult to place this disease under control. By analyzing its genome sequences, we found that type IV fimbrial subunit protein ApfA is highly conserved among different serotypes of A. pleuropneumoniae. Our study shows that ApfA is an adhesin since its expression was greatly upregulated (135-fold) upon contact with host cells, while its deletion mutant attenuated its capability of adhesion. The inactivation of apfA dramatically reduced the ability of A. pleuropneumoniae to colonize mouse lung, suggesting that apfA is a virulence factor. Purified recombinant ApfA elicited an elevated humoral immune response and conferred robust protection against challenges with A. pleuropneumoniae serovar 1 strain 4074 and serovar 7 strain WF83 in mice. Importantly, the anti-ApfA serum conferred significant protection against both serovar 1 and serovar 7 in mice. These studies indicate that ApfA promotes virulence through attachment to host cells, and its immunogenicity renders it a promising novel subunit vaccine candidate against infection with A. pleuropneumoniae. PMID:23269417

Zhou, Yang; Li, Lu; Chen, Zhaohui; Yuan, Hong; Chen, Huanchun

2013-01-01

246

Survival motor neuron protein deficiency impairs myotube formation by altering myogenic gene expression and focal adhesion dynamics.  

PubMed

While spinal muscular atrophy (SMA) is characterized by motor neuron degeneration, it is unclear whether and how much survival motor neuron (SMN) protein deficiency in muscle contributes to the pathophysiology of the disease. There is increasing evidence from patients and SMA model organisms that SMN deficiency causes intrinsic muscle defects. Here we investigated the role of SMN in muscle development using muscle cell lines and primary myoblasts. Formation of multinucleate myotubes by SMN-deficient muscle cells is inhibited at a stage preceding plasma membrane fusion. We found increased expression and reduced induction of key muscle development factors, such as MyoD and myogenin, with differentiation of SMN-deficient cells. In addition, SMN-deficient muscle cells had impaired cell migration and altered organization of focal adhesions and the actin cytoskeleton. Partially restoring SMN inhibited the premature expression of muscle differentiation markers, corrected the cytoskeletal abnormalities and improved myoblast fusion. These findings are consistent with a role for SMN in myotube formation through effects on muscle differentiation and cell motility. PMID:24760765

Bricceno, Katherine V; Martinez, Tara; Leikina, Evgenia; Duguez, Stephanie; Partridge, Terence A; Chernomordik, Leonid V; Fischbeck, Kenneth H; Sumner, Charlotte J; Burnett, Barrington G

2014-09-15

247

The adhesion G protein-coupled receptor GPR56 is a cell-autonomous regulator of oligodendrocyte development.  

PubMed

Mutations in GPR56, a member of the adhesion G protein-coupled receptor family, cause a human brain malformation called bilateral frontoparietal polymicrogyria (BFPP). Magnetic resonance imaging (MRI) of BFPP brains reveals myelination defects in addition to brain malformation. However, the cellular role of GPR56 in oligodendrocyte development remains unknown. Here, we demonstrate that loss of Gpr56 leads to hypomyelination of the central nervous system in mice. GPR56 levels are abundant throughout early stages of oligodendrocyte development, but are downregulated in myelinating oligodendrocytes. Gpr56-knockout mice manifest with decreased oligodendrocyte precursor cell (OPC) proliferation and diminished levels of active RhoA, leading to fewer mature oligodendrocytes and a reduced number of myelinated axons in the corpus callosum and optic nerves. Conditional ablation of Gpr56 in OPCs leads to a reduced number of mature oligodendrocytes as seen in constitutive knockout of Gpr56. Together, our data define GPR56 as a cell-autonomous regulator of oligodendrocyte development. PMID:25607655

Giera, Stefanie; Deng, Yiyu; Luo, Rong; Ackerman, Sarah D; Mogha, Amit; Monk, Kelly R; Ying, Yanqin; Jeong, Sung-Jin; Makinodan, Manabu; Bialas, Allison R; Chang, Bernard S; Stevens, Beth; Corfas, Gabriel; Piao, Xianhua

2015-01-01

248

The C. elegans F-spondin family protein SPON-1 maintains cell adhesion in neural and non-neural tissues  

PubMed Central

Summary The F-spondin family of extracellular matrix proteins has been implicated in axon outgrowth, fasciculation, and neuronal cell migration, as well as differentiation and proliferation of non-neuronal cells. In screens for mutants defective in C. elegans embryonic morphogenesis we identified SPON-1, the only C. elegans member of the spondin family. SPON-1 is synthesized in body muscles and localizes to integrin-containing structures on body muscles and to other basement membranes. SPON-1 maintains strong attachments of muscles to epidermis; in the absence of SPON-1, muscles progressively detach from the epidermis, causing defective epidermal elongation. In animals with reduced integrin function SPON-1 becomes dose-dependent, suggesting SPON-1 and integrins function in concert to promote attachment of muscles to the basement membrane. Although spon-1 mutants display largely normal neurite outgrowth, spon-1 synergizes with outgrowth defective mutants, revealing a cryptic role for SPON-1 in axon extension. In motor neurons SPON-1 acts in axon guidance and fasciculation, whereas in interneurons SPON-1 maintains process position. Our results show that a spondin maintains cell-matrix adhesion in multiple tissues. PMID:18614580

Hudson, Martin L.; Swale, Ryann E.; Goncharov, Alexandr

2008-01-01

249

Decreased sickle red blood cell adhesion to laminin by hydroxyurea is associated with inhibition of Lu/BCAM protein phosphorylation  

E-print Network

1 Decreased sickle red blood cell adhesion to laminin by hydroxyurea is associated with inhibition, published in "Blood 2010;116(12):2152-9" DOI : 10.1182/blood-2009-12-257444 #12;2 Abstract Sickle-cell laminin receptor Lu/BCAM was increased but red blood cell adhesion to laminin decreased. Because Lu

Paris-Sud XI, Université de

250

T cells respond to heat shock protein 60 via TLR2: activation of adhesion and inhibition of chemokine receptors.  

PubMed

Soluble 60 kDa heat shock protein (HSP60) activates macrophages via TLR4. We now report that soluble HSP60 activates T cells via the innate receptor TLR2. HSP60 activated T cell adhesion to fibronectin to a degree similar to other activators: IL-2, SDF-1alpha, and RANTES. T cell type and state of activation was important; nonactivated CD45RA+ and IL-2-activated CD45RO+ T cells responded optimally (1 h) at low concentrations (0.1-1 ng/ml), but nonactivated CD45RO+ T cells required higher concentrations (approximately 1 microg/ml) of HSP60. T cell HSP60 signaling was inhibited specifically by monoclonal antibodies (mAb) to TLR2 but not by a mAb to TLR4. Indeed, T cells from mice with mutated TLR4 could still respond to HSP60, whereas Chinese hamster T cells with mutated TLR2 did not respond. The human T cell response to soluble HSP60 depended on phosphatidylinositol 3-kinase and protein kinase C signaling and involved the phosphorylation of Pyk-2. Soluble HSP60 also inhibited actin polymerization and T cell chemotaxis through extracellular matrix-like gels toward the chemokines SDF-1alpha (CXCL12) or ELC (CCL19). Exposure to HSP60 for longer times (18 h) down-regulated chemokine receptor expression: CXCR4 and CCR7. These results suggest that soluble HSP60, through TLR2-dependent interactions, can regulate T cell behavior in inflammation. PMID:12824285

Zanin-Zhorov, Alexandra; Nussbaum, Gabriel; Franitza, Susanne; Cohen, Irun R; Lider, Ofer

2003-08-01

251

Adhesion Properties of Catechol-Based Biodegradable Amino Acid-Based Poly(ester urea) Copolymers Inspired from Mussel Proteins.  

PubMed

Amino acid-based poly(ester urea) (PEU) copolymers functionalized with pendant catechol groups that address the need for strongly adhesive yet degradable biomaterials have been developed. Lap-shear tests with aluminum adherends demonstrated that these polymers have lap-shear adhesion strengths near 1 MPa. An increase in lap-shear adhesive strength to 2.4 MPa was achieved upon the addition of an oxidative cross-linker. The adhesive strength on porcine skin adherends was comparable with commercial fibrin glue. Interfacial energies of the polymeric materials were investigated via contact angle measurements and Johnson-Kendall-Roberts (JKR) technique. The JKR work of adhesion was consistent with contact angle measurements. The chemical and physical properties of PEUs can be controlled using different diols and amino acids, making the polymers candidates for the development of biological glues for use in clinical applications. PMID:25427310

Zhou, Jinjun; Defante, Adrian P; Lin, Fei; Xu, Ying; Yu, Jiayi; Gao, Yaohua; Childers, Erin; Dhinojwala, Ali; Becker, Matthew L

2015-01-12

252

Immunoelectron microscopic localization of neural cell adhesion molecules (L1, N-CAM, and MAG) and their shared carbohydrate epitope and myelin basic protein in developing sciatic nerve  

Microsoft Academic Search

The cellular and subcellular localization of the neural cell adhesion molecules L1, N-CAM, and myelin-associated glycoprotein (MAG), their shared carbohydrate epitope L2\\/HNK-1, and the myelin basic protein (MBP) were studied by pre- and post- embedding immunoelectron microscopic labeling procedures in developing mouse sciatic nerve. L1 and N-CAM showed a similar staining pattern. Both were localized on small, non-myelinated, fasciculating axons

Rudolf Martini; Melitta Schachner

1986-01-01

253

Adhesive properties and inflammatory potential of citrullinated myelin basic protein peptide 45-89.  

PubMed

Deimination of arginyl residue of myelin basic protein (MBP) reduces cationicity of MBP and impedes the normal myelin membrane assembly. Less ordered structure of MBP is more susceptible to proteolytic attack that may lead to the release of highly immunogenic deiminated peptides into extracellular milieu. We have studied the association of peptides 45-89 derived from citrullinated MBP (C8 isomer) and phosphorylated MBP (C3 isomer) with the myelin lipids in a model membrane system using optical waveguide lightmode spectrometry. The analysis of association/dissociation kinetics to planar lipids under controlled hydrodynamic conditions has shown that MBP 45-89 peptide from citrullinated C8 isomer is less effectively adsorbed on the lipid membrane, than peptide from phosphorylated C3 isomer and packing densities for phosphorylated 45-89 MBP peptide is higher than for citrullinated forms. On the other hand, our results shown that continuous (24 h) exposure of mixed oligodendrocyte/microglial cells to peptides 45-89 from MBP-C8 induces apoptosis via mitochondrial pathway. In addition, peptides 45-89 stimulated the secretion of nitric oxide from microglial cells via induction of iNOS and decreased the level of the inhibitory protein IkB, indicating involvement of the transcription factor NF-kB in these processes. Our results suggest that some citrullinated peptides, initially released from oligodendrocytes, might activate microglia, which produces reactive nitrogen species and generates in turn fatal feedbacks that kill oligodendrocytes. PMID:22678722

Shanshiashvili, Lali V; Kalandadze, Irina V; Ramsden, Jeremy J; Mikeladze, David G

2012-09-01

254

Composites containing albumin protein or cyanoacrylate adhesives and biodegradable scaffolds: I. Acute wound closure study in a rat model  

NASA Astrophysics Data System (ADS)

Composite adhesives composed of biodegradable scaffolds impregnated with a biological or synthetic adhesive were investigated for use in wound closure as an alternative to using either one of the adhesives alone. Two different scaffold materials were investigated: (i) a synthetic biodegradable material fabricated from poly(L-lactic-co-glycolic acid); and (ii) a biological material, small intestinal sub mucosa, manufactured by Cook BioTech. The biological adhesive was 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. The synthetic adhesive was Ethicon's Dermabond, a 2-octyl-cyanoacrylate. The tensile strength of skin incisions repaired ex vivo in a rat model, by adhesive alone or in combination with a scaffold, as well as the time-to-failure, were measured and compared. The tensile strength of repairs formed using the scaffold-enhanced biological adhesives were on average, 80% stronger than their non-enhanced counterparts, with an accompanying increase in the time-to-failure of the repairs. These results support the theory that a scaffold material with an irregular surface that bridges the wound provides a stronger, more durable and consistent adhesion, due to the distribution of the tensile stress forces over the many micro-adhesions provided by the irregular surface, rather than the one large continuous adhesive contact. This theory is also supported by several previous ex vivo experiments demonstrating enhanced tensile strength of irregular versus smooth scaffold surfaces in identical tissue repairs performed on bovine thoracic aorta, liver, spleen, small intestine and lung tissue.

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

2004-07-01

255

Activation-dependent redistribution of the adhesion plaque protein, talin, in intact human platelets [published erratum appears in J Cell Biol 1990 Mar;110(3):865  

PubMed Central

Talin is a high molecular weight protein localized at adhesion plaques in fibroblasts. It binds vinculin and integrin and appears to participate in generating a transmembrane connection between the extracellular matrix and the cytoskeleton. We have recently shown that talin is an abundant protein in platelets, cells highly specialized for regulated adhesion. Although talin constitutes greater than 3% of the total protein in intact human platelets, its location within the cells had not been defined. In the work reported here, we have investigated the distribution of talin in resting and activated human platelets by immunofluorescence and immunoelectron microscopy. We have found that talin undergoes an activation-dependent change in its subcellular location. In resting platelets, which are nonadhesive, talin is uniformly distributed throughout the cytoplasm. In contrast, in thrombin- and glass-activated, substratum-adherent platelets, talin is concentrated at the cytoplasmic face of the plasma membrane. This dramatic, regulated redistribution of talin raises the possibility that talin plays a role in the controlled development of platelet adhesion. PMID:2513330

1989-01-01

256

First study on gene expression of cement proteins and potential adhesion-related genes of a membranous-based barnacle as revealed from Next-Generation Sequencing technology.  

PubMed

This is the first study applying Next-Generation Sequencing (NGS) technology to survey the kinds, expression location, and pattern of adhesion-related genes in a membranous-based barnacle. A total of 77,528,326 and 59,244,468 raw sequence reads of total RNA were generated from the prosoma and the basis of Tetraclita japonica formosana, respectively. In addition, 55,441 and 67,774 genes were further assembled and analyzed. The combined sequence data from both body parts generates a total of 79,833 genes of which 47.7% were shared. Homologues of barnacle cement proteins - CP-19K, -52K, and -100K - were found and all were dominantly expressed at the basis where the cement gland complex is located. This is the main area where transcripts of cement proteins and other potential adhesion-related genes were detected. The absence of another common barnacle cement protein, CP-20K, in the adult transcriptome suggested a possible life-stage restricted gene function and/or a different mechanism in adhesion between membranous-based and calcareous-based barnacles. PMID:24329402

Lin, Hsiu-Chin; Wong, Yue Him; Tsang, Ling Ming; Chu, Ka Hou; Qian, Pei-Yuan; Chan, Benny K K

2014-02-01

257

Cell surface anchorage and ligand-binding domains of the Saccharomyces cerevisiae cell adhesion protein alpha-agglutinin, a member of the immunoglobulin superfamily.  

PubMed Central

alpha-Agglutinin is a cell adhesion glycoprotein expressed on the cell wall of Saccharomyces cerevisiae alpha cells. Binding of alpha-agglutinin to its ligand a-agglutinin, expressed by a cells, mediates cell-cell contact during mating. Analysis of truncations of the 650-amino-acid alpha-agglutinin structural gene AG alpha 1 delineated functional domains of alpha-agglutinin. Removal of the C-terminal hydrophobic sequence allowed efficient secretion of the protein and loss of cell surface attachment. This cell surface anchorage domain was necessary for linkage to a glycosyl phosphatidylinositol anchor. A construct expressing the N-terminal 350 amino acid residues retained full a-agglutinin-binding activity, localizing the binding domain to the N-terminal portion of alpha-agglutinin. A 278-residue N-terminal peptide was inactive; therefore, the binding domain includes residues between 278 and 350. The segment of alpha-agglutinin between amino acid residues 217 and 308 showed significant structural and sequence similarity to a consensus sequence for immunoglobulin superfamily variable-type domains. The similarity of the alpha-agglutinin-binding domain to mammalian cell adhesion proteins suggests that this structure is a highly conserved feature of adhesion proteins in diverse eukaryotes. Images PMID:8455628

Wojciechowicz, D; Lu, C F; Kurjan, J; Lipke, P N

1993-01-01

258

Surface-bound proteins of Lactobacillus plantarum 423 that contribute to adhesion of Caco-2 cells and their role in competitive exclusion and displacement of Clostridium sporogenes and Enterococcus faecalis  

Microsoft Academic Search

Elongation factor Tu (EF-Tu), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and triosephosphate isomerase (TPI) are surface-bound proteins with a role in adhesion of Lactobacillus plantarum 423 to Caco-2 cells. Removal of surface-bound proteins from L. plantarum 423 (treated with 4M guanidine–HCl) reduced adhesion to Caco-2 cells by 40%. In a competitive exclusion experiment where all three strains were given an equal chance to

Kamini Ramiah; Carol A. van Reenen; Leon M. T. Dicks

2008-01-01

259

Optimal Germinal Center Responses Require A Multi-stage T:B Cell Adhesion Process Involving Integrins, SLAM-associated protein and CD84  

PubMed Central

CD4+ T cells deficient in signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) exhibit a selective impairment in adhesion to antigen presenting B cells but not dendritic cells (DC), resulting in defective germinal center formation. However, the nature of this selective adhesion defect remained unclear. We found that whereas T:DC interactions were primarily integrin-dependent, T:B cell interactions had both an early integrin-dependent phase and a sustained phase that also required SAP. We further found that the SLAM family member, CD84, was required for prolonged T:B cell contact, optimal T follicular helper function, and germinal center formation in vivo. Moreover, both CD84 and another SLAM member, Ly108, mediated T cell adhesion and participated in stable T:B cell interactions in vitro. Our results reveal insight into the dynamic regulation of T:B cell interactions and identify SLAM family members as critical components of sustained T:B cell adhesion required for productive humoral immunity. PMID:20153220

Cannons, Jennifer L.; Qi, Hai; Lu, Kristina T.; Ghai, Mala; Gomez-Rodriguez, Julio; Cheng, Jun; Wakeland, Edward K.; Germain, Ronald N.; Schwartzberg, Pamela L.

2010-01-01

260

Enhanced protein adsorption and cellular adhesion using transparent titanate nanotube thin films made by a simple and inexpensive room temperature process: application to optical biochips.  

PubMed

A new type of titanate nanotube (TNT) coating is investigated for exploitation in biosensor applications. The TNT layers were prepared from stable but additive-free sols without applying any binding compounds. The simple, fast spin-coating process was carried out at room temperature, and resulted in well-formed films around 10nm thick. The films are highly transparent as expected from their nanostructure and may, therefore, be useful as coatings for surface-sensitive optical biosensors to enhance the specific surface area. In addition, these novel coatings could be applied to medical implant surfaces to control cellular adhesion. Their morphology and structure was characterized by spectroscopic ellipsometry (SE) and atomic force microscopy (AFM), and their chemical state by X-ray photoelectron spectroscopy (XPS). For quantitative surface adhesion studies, the films were prepared on optical waveguides. The coated waveguides were shown to still guide light; thus, their sensing capability remains. Protein adsorption and cell adhesion studies on the titanate nanotube films and on smooth control surfaces revealed that the nanostructured titanate enhanced the adsorption of albumin; furthermore, the coatings considerably enhanced the adhesion of living mammalian cells (human embryonic kidney and preosteoblast). PMID:25092586

Nador, Judit; Orgovan, Norbert; Fried, Miklos; Petrik, Peter; Sulyok, Attila; Ramsden, Jeremy J; Korosi, Laszlo; Horvath, Robert

2014-10-01

261

Bistability of Cell Adhesion in Shear Flow  

E-print Network

Cell adhesion plays a central role in multicellular organisms helping to maintain their integrity and homeostasis. This complex process involves many different types of adhesion proteins, and synergetic behavior of these ...

Efremov, Artem

262

Identification of glycoprotein components of alpha-agglutinin, a cell adhesion protein from Saccharomyces cerevisiae.  

PubMed Central

Several glycoproteins which inhibit the agglutinability of Saccharomyces cerevisiae mating type a cells were partially purified from extracts of mating type alpha cells. These proteins, called alpha-agglutinin, were labeled with 125I-Bolton-Hunter reagent. The labeled alpha-agglutinin showed specific binding to a cells. Such specific binding approached saturation with respect to agglutinin or cells and was inhibited in the presence of excess unlabeled alpha-agglutinin. Nonspecific binding was similar in a and alpha cells, was neither saturable nor competable, and was three- to fourfold less than the specific binding to a cells at maximum tested agglutinin concentrations. The major a-specific binding species had a low electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gels and had an apparent molecular weight of 155,000 by rate zonal centrifugation. Endo-N-acetylglucosaminidase H digestion of the purified glycoprotein complex converted the low-mobility material to four major and several minor bands which were resolved by polyacrylamide gel electrophoresis. All but two minor peptides bound specifically to a cells. Analyses of agglutinin from mnn mutants confirmed the deglycosylation results in suggesting that the N-linked carbohydrate portion of alpha-agglutinin was not necessary for activity. Images PMID:3542959

Terrance, K; Heller, P; Wu, Y S; Lipke, P N

1987-01-01

263

Octamer-binding protein 4 affects the cell biology and phenotypic transition of lung cancer cells involving ?-catenin/E-cadherin complex degradation.  

PubMed

Clinical studies have reported evidence for the involvement of octamer?binding protein 4 (Oct4) in the tumorigenicity and progression of lung cancer; however, the role of Oct4 in lung cancer cell biology in vitro and its mechanism of action remain to be elucidated. Mortality among lung cancer patients is more frequently due to metastasis rather than their primary tumors. Epithelial?mesenchymal transition (EMT) is a prominent biological event for the induction of epithelial cancer metastasis. The aim of the present study was to investigate whether Oct4 had the capacity to induce lung cancer cell metastasis via the promoting the EMT in vitro. Moreover, the effect of Oct4 on the ??catenin/E?cadherin complex, associated with EMT, was examined using immunofluorescence and immunoprecipitation assays as well as western blot analysis. The results demonstrated that Oct4 enhanced cell invasion and adhesion accompanied by the downregulation of epithelial marker cytokeratin, and upregulation of the mesenchymal markers vimentin and N?cadherin. Furthermore, Oct4 induced EMT of lung cancer cells by promoting ??catenin/E?cadherin complex degradation and regulating nuclear localization of ??catenin. In conclusion, the present study indicated that Oct4 affected the cell biology of lung cancer cells in vitro through promoting lung cancer cell metastasis via EMT; in addition, the results suggested that the association and degradation of the ??catenin/E?cadherin complex was regulated by Oct4 during the process of EMT. PMID:25420671

Chen, Zhong-Shu; Ling, Dong-Jin; Zhang, Yang-De; Feng, Jian-Xiong; Zhang, Xue-Yu; Shi, Tian-Sheng

2015-03-01

264

Candida albicans Uses the Surface Protein Gpm1 to Attach to Human Endothelial Cells and to Keratinocytes via the Adhesive Protein Vitronectin  

PubMed Central

Candida albicans is a major cause of invasive fungal infections worldwide. Upon infection and when in contact with human plasma as well as body fluids the fungus is challenged by the activated complement system a central part of the human innate immune response. C. albicans controls and evades host complement attack by binding several human complement regulators like Factor H, Factor H-like protein 1 and C4BP to the surface. Gpm1 (Phosphoglycerate mutase 1) is one fungal Factor H/FHL1 -binding protein. As Gpm1 is surface exposed, we asked whether Gpm1 also contributes to host cell attachment. Here, we show by flow cytometry and by laser scanning microscopy that candida Gpm1 binds to human umbilical vein endothelial cells (HUVEC) to keratinocytes (HaCaT), and also to monocytic U937 cells. Wild type candida did bind, but the candida gpm1?/? knock-out mutant did not bind to these human cells. In addition Gpm1when attached to latex beads also conferred attachment to human endothelial cells. When analyzing Gpm1-binding to a panel of extracellular matrix proteins, the human glycoprotein vitronectin was identified as a new Gpm1 ligand. Vitronectin is a component of the extracellular matrix and also a regulator of the terminal complement pathway. Vitronectin is present on the surface of HUVEC and keratinocytes and acts as a surface ligand for fungal Gpm1. Gpm1 and vitronectin colocalize on the surface of HUVEC and HaCaT as revealed by laser scanning microscopy. The Gpm1 vitronectin interaction is inhibited by heparin and the interaction is also ionic strength dependent. Taken together, Gpm1 the candida surface protein binds to vitronectin and mediates fungal adhesion to human endothelial cells. Thus fungal Gpm1 and human vitronectin represent a new set of proteins that are relevant for fungal attachment to human cells interaction. Blockade of the Gpm1 vitronectin interaction might provide a new target for therapy. PMID:24625558

Lopez, Crisanto M.; Wallich, Reinhard; Riesbeck, Kristian; Skerka, Christine; Zipfel, Peter F.

2014-01-01

265

Rbt1 protein domains analysis in Candida albicans brings insights into hyphal surface modifications and Rbt1 potential role during adhesion and biofilm formation.  

PubMed

Cell wall proteins are central to the virulence of Candida albicans. Hwp1, Hwp2 and Rbt1 form a family of hypha-associated cell surface proteins. Hwp1 and Hwp2 have been involved in adhesion and other virulence traits but Rbt1 is still poorly characterized. To assess the role of Rbt1 in the interaction of C. albicans with biotic and abiotic surfaces independently of its morphological state, heterologous expression and promoter swap strategies were applied. The N-terminal domain with features typical of the Flo11 superfamily was found to be essential for adhesiveness to polystyrene through an increase in cell surface hydrophobicity. A 42 amino acid-long domain localized in the central part of the protein was shown to enhance the aggregation function. We demonstrated that a VTTGVVVVT motif within the 42 amino acid domain displayed a high ?-aggregation potential and was responsible for cell-to-cell interactions by promoting the aggregation of hyphae. Finally, we showed through constitutive expression that while Rbt1 was directly accessible to antibodies in hyphae, it was not so in yeast. Similar results were obtained for another cell wall protein, namely Iff8, and suggested that modification of the cell wall structure between yeast and hyphae can regulate the extracellular accessibility of cell wall proteins independently of gene regulation. PMID:24349274

Monniot, Céline; Boisramé, Anita; Da Costa, Grégory; Chauvel, Muriel; Sautour, Marc; Bougnoux, Marie-Elisabeth; Bellon-Fontaine, Marie-Noëlle; Dalle, Frédéric; d'Enfert, Christophe; Richard, Mathias L

2013-01-01

266

Rbt1 Protein Domains Analysis in Candida albicans Brings Insights into Hyphal Surface Modifications and Rbt1 Potential Role during Adhesion and Biofilm Formation  

PubMed Central

Cell wall proteins are central to the virulence of Candida albicans. Hwp1, Hwp2 and Rbt1 form a family of hypha-associated cell surface proteins. Hwp1 and Hwp2 have been involved in adhesion and other virulence traits but Rbt1 is still poorly characterized. To assess the role of Rbt1 in the interaction of C. albicans with biotic and abiotic surfaces independently of its morphological state, heterologous expression and promoter swap strategies were applied. The N-terminal domain with features typical of the Flo11 superfamily was found to be essential for adhesiveness to polystyrene through an increase in cell surface hydrophobicity. A 42 amino acid-long domain localized in the central part of the protein was shown to enhance the aggregation function. We demonstrated that a VTTGVVVVT motif within the 42 amino acid domain displayed a high ?-aggregation potential and was responsible for cell-to-cell interactions by promoting the aggregation of hyphae. Finally, we showed through constitutive expression that while Rbt1 was directly accessible to antibodies in hyphae, it was not so in yeast. Similar results were obtained for another cell wall protein, namely Iff8, and suggested that modification of the cell wall structure between yeast and hyphae can regulate the extracellular accessibility of cell wall proteins independently of gene regulation. PMID:24349274

Da Costa, Grégory; Chauvel, Muriel; Sautour, Marc; Bougnoux, Marie-Elisabeth; Bellon-Fontaine, Marie-Noëlle; Dalle, Frédéric; d’Enfert, Christophe; Richard, Mathias L.

2013-01-01

267

Serum Vascular Adhesion Protein-1 Predicts 10-Year Cardiovascular and Cancer Mortality in Individuals With Type 2 Diabetes  

PubMed Central

OBJECTIVE Vascular adhesion protein-1 (VAP-1) participates in inflammation and catalyzes the breakdown of amines to produce aldehyde, hydrogen peroxide, and ammonia. Serum VAP-1 correlates positively with both acute hyperglycemia and diabetes. We conducted a cohort study to evaluate whether serum VAP-1 predicts 10-year survival in type 2 diabetic patients. RESEARCH DESIGN AND METHODS Between July 1996 and June 2003, we enrolled 661 type 2 diabetic subjects at National Taiwan University Hospital. Serum VAP-1 in the samples obtained at enrollment was measured by time-resolved immunofluorometric assay. The vital status of all subjects was ascertained by linking their data with computerized death certificates in Taiwan. RESULTS The medium follow-up period was 10.4 years. Subjects with serum VAP-1 in the highest tertile had a hazard ratio (HR) of 2.19 (95% CI 1.17–4.11) for all-cause mortality adjusted for age, sex, smoking, history of cardiovascular disease, obesity, hypertension, hemoglobin A1c, diabetes duration, total cholesterol, use of statins, abnormal ankle-brachial index, estimated glomerular filtration rate (eGFR), and proteinuria. The adjusted HRs for logarithmically transformed serum VAP-1 were 5.83 (95% CI 1.17–28.97) for cardiovascular mortality, 6.32 (95% CI 1.25–32.00) for mortality from cardiovascular and diabetic causes, and 17.24 (95% CI 4.57–65.07) for cancer mortality. There were four variables, including age, serum VAP-1, proteinuria, and eGFR, which could enhance mortality prediction significantly. CONCLUSIONS Serum VAP-1 can predict 10-year all-cause mortality, cardiovascular mortality, and cancer mortality independently in type 2 diabetic subjects. Serum VAP-1 is a novel biomarker that improves risk prediction over and above established risk factors. PMID:21282368

Li, Hung-Yuan; Jiang, Yi-Der; Chang, Tien-Jyun; Wei, Jung-Nan; Lin, Mao-Shin; Lin, Cheng-Hsin; Chiang, Fu-Tien; Shih, Shyang-Rong; Hung, Chi Sheng; Hua, Cyue-Huei; Smith, David J.; Vanio, Jani; Chuang, Lee-Ming

2011-01-01

268

Chitinase 3-like-1 enhances bacterial adhesion to colonic epithelial cells through the interaction with bacterial chitin-binding protein  

Microsoft Academic Search

Dysregulated host\\/microbial interactions play a pivotal role in the pathogenesis of inflammatory bowel disease. We previously reported that chitinase 3-like-1 (CHI3L1) enhances bacterial adhesion and invasion on\\/into colonic epithelial cells (CECs). In this study, we designed to identify the exact mechanism of how CHI3L1 enhances the bacterial adhesion on CECs in vitro. As compared with wild type (WT) of Serratia

Mayumi Kawada; Chun-Chuan Chen; Atsuko Arihiro; Katsuya Nagatani; Takeshi Watanabe; Emiko Mizoguchi

2008-01-01

269

Upregulation of adhesion complex proteins and fibronectin by human keratinocytes treated with an aqueous extract from the leaves of Chromolaena odorata (Eupolin).  

PubMed

The fresh leaves and extract of the plant Chromolaena odorata are a traditional herbal treatment in developing countries for burns, soft tissue wounds and skin infections. We have previously shown that the extract had an effect on the growth and proliferation of keratinocytes and fibroblasts in culture. This study has demonstrated that Eupolin extract increased expression of several components of the adhesion complex and fibronectin by human keratinocytes. Using indirect immunofluorescence we found increased expression (dose-dependent) of laminin 5, laminin 1, collagen IV, and fibronectin. The expression of the b1 and b4 integrins was upregulated by the extract at low concentrations (0.1 and 1 microg/ml), but the expression was decreased at higher doses of Eupolin (10 microg-150 microg/ml). A number of clinical studies carried out by Vietnamese and international medical investigators have demonstrated the efficacy of this extract on the wound healing process. In this study we have shown that Eupolin stimulated the expression of many proteins of the adhesion complex and fibronectin by human keratinocytes. The adhesion complex proteins are essential to stabilise epithelium and this effect could contribute to the clinical efficacy of Eupolin in healing. PMID:11056422

Phan, T T; Allen, J; Hughes, M A; Cherry, G; Wojnarowska, F

2000-01-01

270

Structure-based rational design of beta-hairpin peptides from discontinuous epitopes of cluster of differentiation 2 (CD2) protein to modulate cell adhesion interaction.  

PubMed

Modulation or inhibition of interaction of cluster of differentiation (CD) adhesion molecules CD2-CD58 has been shown to be therapeutically useful. The analysis of the crystal structure of CD2 complexed with CD58 was carried out to define the epitopes that are important for the interaction of the two proteins. The crystal structure of CD2 indicated that the interaction surface of CD2 with CD58 has two beta-strand structures (F and C strands) with charged residues. On the basis of the crystal structure of the complex CD2-CD58, we have designed beta-hairpin peptides from the beta-strand region of CD2 by conjugating the discontinuous sequences in the protein. The peptides were modeled by molecular dynamics simulation, and their inhibitory activities were evaluated in vitro using two heterotypic cell adhesion assays, E-rosetting and lymphocyte-epithelial cell adhesion assays. Results indicated that 12- and 14-residue conjugate cyclic peptides cKS12 and cDD14 exhibited 60% and 50% inhibition activity, respectively, at 90 microM. PMID:17658775

Liu, Jining; Li, Cheng; Ke, Shao; Satyanarayanajois, Seetharama D

2007-08-23

271

Glucocorticoid-induced tumour necrosis factor receptor-related protein-mediated macrophage stimulation may induce cellular adhesion and cytokine expression in rheumatoid arthritis  

PubMed Central

Glucocorticoid-induced tumour necrosis factor receptor (TNFR)-related protein (GITR) is one of the T cell co-stimulatory molecules and is associated with the pathogenesis of a number of autoimmune diseases. We investigated the expression patterns of GITR in human arthritic synovium and the role of GITR in the pathogenesis of rheumatoid arthritis (RA). Immunohistochemical analyses revealed the expression of GITR and its cognate ligand, GITRL, in macrophages in RA, but not in osteoarthritis (OA), synovium. To investigate the role of GITR in macrophage functions, primary macrophages from RA patients and a human macrophage cell line, THP-1, were analysed. Stimulation of the macrophages with anti-GITR monoclonal antibody induced up-regulation of intercellular adhesion molecule (ICAM)-1 and subsequent aggregation/adhesion, which was enhanced by the presence of extracellular matrix proteins and blocked by anti-ICAM-1 monoclonal antibody. The validity of these in vitro observations was confirmed by immunohistochemical analyses of RA synovium, which showed strong expression of ICAM-1 in GITR-positive macrophages. Additionally, GITR stimulation induced expression of proinflammatory cytokines/chemokines and matrix metalloproteinase-9 in synovial macrophages. These data indicate that GITR, expressed on macrophages in human RA synovium, may enhance inflammatory activation of macrophages by promoting cytokine gene expression and adhesion between cells and to extracellular matrix in RA synovium. PMID:17359498

Bae, E; Kim, W-J; Kang, Y-M; Suk, K; Koh, E-M; Cha, H-S; Ahn, K-S; Huh, T-L; Lee, W-H

2007-01-01

272

TNF-alpha associated with fibronectin enhances phorbol myristate acetate- or antigen-mediated integrin-dependent adhesion of CD4+ T cells via protein tyrosine phosphorylation.  

PubMed

The effects of cytokines on immune cells may be influenced by their milieu, such as the extracellular matrix (ECM), in the vicinities of which cytokines and inflammatory cells interact and function. Previously, we demonstrated that TNF-alpha bound to fibronectin (FN) and augments the level of adhesion of activated CD4+ cells. Herein, we examined the mechanisms of this pro-adhesive activity of TNF-alpha and its putative physiologic consequences using human or rat CD4+ cells. A brief exposure of CD4+ cells to low dosages of soluble TNF-alpha or of FN- or laminin-bound TNF-alpha synergized with PMA to enhance the integrin-mediated binding of CD4+ cells to these immobilized ECM moieties. TNF-alpha-enhanced adhesion of CD4+ cells did not delay or inhibit the subsequent detachment of the cells from the substrate, and adhesion was increased provided the cells were treated with TNF-alpha immediately after their exposure to PMA. This indicates that the enhancing effect of TNF-alpha requires a previous activation of the cells. When TNF-alpha was immobilized on FN, less TNF-alpha was required to induce CD4+ cell binding to FN. Soluble, and to a greater extent FN-bound, TNF-alpha synergizes with PMA to intensify protein tyrosine phosphorylation in FN-bound CD4+ cells, and this effect of TNF-alpha was inhibited by inhibitors of tyrosine kinase. That FN-bound or soluble TNF-alpha also amplified the binding of an Ag-specific autoimmune rat T cell line to immobilized FN, emphasizes the physiologic relevance of our findings. Thus, the signal transduction and cell adhesive properties of ECM glycoproteins may be modulated upon their association with TNF-alpha, and matrix-linked TNF-alpha may recruit and direct immune cells to inflammatory sites. PMID:7517419

Hershkoviz, R; Cahalon, L; Miron, S; Alon, R; Sapir, T; Akiyama, S K; Yamada, K M; Lider, O

1994-07-15

273

Thioredoxin1 Downregulates Oxidized Low-Density Lipoprotein-Induced Adhesion Molecule Expression via Smad3 Protein  

PubMed Central

Atherosclerosis is a chronic inflammation disease that is initiated by endothelial cell injury. Oxidized low-density lipoprotein (ox-LDL) is directly associated with chronic vascular inflammation. To understand whether thioredoxin1 (Trx1) participates in an antiinflammatory defense mechanism in atherosclerosis, we investigated the effect of Trx1 on the expression of two adhesion molecules, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), in human umbilical vein endothelial cells (HUVECs). Thioredoxin1 and dominant-negative mutant thioredoxin1 (TD) were transiently overexpressed using adenovirus vector gene transfer. Our data showed that Trx1 overexpression suppressed ox-LDL-induced adhesion molecule expression in HUVECs. The overexpression of Trx1 promoted ox-LDL-induced Smad3 phosphorylation and nuclear translocation. A co-immunoprecipitation assay indicated that Smad3 continued to interact with Trx1 with or without ox-LDL stimulation. These results suggest that Trx1 inherently suppresses VCAM-1 and ICAM-1 expression in vascular endothelia and may prevent the initiation of atherosclerosis by attenuating adhesion molecule expression. The enhancement of Smad3 phosphorylation and nuclear expression appears to be primarily responsible for the Trx1-induced downregulation of adhesion molecules. PMID:24086714

Chen, Beidong; Wang, Wendong; Shen, Tao; Qi, Ruomei

2013-01-01

274

Bistability of Cell Adhesion in Shear Flow Artem Efremov  

E-print Network

Bistability of Cell Adhesion in Shear Flow Artem Efremov * and Jianshu Cao * Singapore of Technology, Cambridge, Massachusetts ABSTRACT Cell adhesion plays a central role in multicellular organisms of adhesion proteins, and synergetic behavior of these proteins during cell adhesion is frequently observed

Cao, Jianshu

275

The Src homology 2 protein Shb promotes cell cycle progression in murine hematopoietic stem cells by regulation of focal adhesion kinase activity  

SciTech Connect

The widely expressed adaptor protein Shb has previously been reported to contribute to T cell function due to its association with the T cell receptor and furthermore, several of Shb's known interaction partners are established regulators of blood cell development and function. In addition, Shb deficient embryonic stem cells displayed reduced blood cell colony formation upon differentiation in vitro. The aim of the current study was therefore to explore hematopoietic stem and progenitor cell function in the Shb knockout mouse. Shb deficient bone marrow contained reduced relative numbers of long-term hematopoietic stem cells (LT-HSCs) that exhibited lower proliferation rates. Despite this, Shb knockout LT-HSCs responded promptly by entering the cell cycle in response to genotoxic stress by 5-fluorouracil treatment. In competitive LT-HSC transplantations, Shb null cells initially engrafted as well as the wild-type cells but provided less myeloid expansion over time. Moreover, Shb knockout bone marrow cells exhibited elevated basal activities of focal adhesion kinase/Rac1/p21-activated kinase signaling and reduced responsiveness to Stem Cell Factor stimulation. Consequently, treatment with a focal adhesion kinase inhibitor increased Shb knockout LT-HSC proliferation. The altered signaling characteristics thus provide a plausible mechanistic explanation for the changes in LT-HSC proliferation since these signaling intermediates have all been shown to participate in LT-HSC cell cycle control. In summary, the loss of Shb dependent signaling in bone marrow cells, resulting in elevated focal adhesion kinase activity and reduced proliferative responses in LT-HSCs under steady state hematopoiesis, confers a disadvantage to the maintenance of LT-HSCs over time. -- Highlights: • Shb is an adaptor protein operating downstream of tyrosine kinase receptors. • Shb deficiency reduces hematopoietic stem cell proliferation. • The proliferative effect of Shb occurs via increased focal adhesion kinase activity. • Shb is critical for the long-term maintenance of the hematopoietic stem cell pool.

Gustafsson, Karin [Department of Medical Cell Biology, Uppsala University, Uppsala 751 23 (Sweden); Heffner, Garrett; Wenzel, Pamela L.; Curran, Matthew [HHMI, Children's Hospital Boston, Harvard Medical School, Boston, 02115 MA (United States); Grawé, Jan [Department of Genetics and Pathology, Uppsala University, Uppsala 75185 (Sweden); McKinney-Freeman, Shannon L. [Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN 38105 (United States); Daley, George Q. [HHMI, Children's Hospital Boston, Harvard Medical School, Boston, 02115 MA (United States); Welsh, Michael, E-mail: michael.welsh@mcb.uu.se [Department of Medical Cell Biology, Uppsala University, Uppsala 751 23 (Sweden)

2013-07-15

276

Deletion of an amino-terminal sequence beta-catenin in vivo and promotes hyperphosporylation of the adenomatous polyposis coli tumor suppressor protein.  

PubMed Central

Regulation of cell adhesion and cell signaling by beta-catenin occurs through a mechanism likely involving the targeted degradation of the protein. Deletional analysis was used to generate a beta-catenin refractory to rapid turnover and to examine its effects on complexes containing either cadherin or the adenomatous polyposis coli (APC) protein. The results show that amino-terminal deletion of beta-catenin results in a protein with increased stability that acts in a dominant fashion with respect to wild-type beta-catenin. Constitutive expression in AtT20 cells of a beta-catenin lacking 89 N-terminal amino acids (deltaN89beta-catenin) resulted in severely reduced levels of the more labile wild-type beta-catenin. The mutant beta-catenin was expressed at endogenous levels but displaced the vast majority of wild-type beta-catenin associated with N-cadherin. The deltaN89beta-catenin accumulated on the APC protein to a level 10-fold over that of wild-type beta-catenin and recruited a kinase into the APC complex. The kinase was highly active toward APC in vitro and promoted a sodium dodecyl sulfate gel band shift that was also evident for endogenous APC from cells expressing the mutant beta-catenin. Unlike wild-type beta-catenin, which partitions solely as part of a high-molecular-weight complex, the deltaN89 mutant protein also fractionated as a stable monomer, indicating that it had escaped the requirement to associate with other proteins. That similar N-terminal mutants of beta-catenin have been implicated in cellular transformation suggests that their abnormal association with APC may, in part, be responsible for this phenotype. PMID:8754807

Munemitsu, S; Albert, I; Rubinfeld, B; Polakis, P

1996-01-01

277

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

SciTech Connect

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 receptor neogenin signals to activate FAK; both processes promote muscle-specific gene expression and myoblast fusion. M-cadherin activates Rac1 to enhance fusion. Specific Ig receptors (Kirre and Sns) are essential for myoblast fusion in Drosophila, also signaling through Rac, and vertebrate orthologs of Kirre and Sns have partially conserved function. Mice lacking specific cytoplasmic signaling factors activated by multiple receptors (e.g., Rac1) have strong muscle phenotypes in vivo. In contrast, mice lacking individual adhesion receptors that lie upstream of these factors have modest phenotypes. Redundancy among receptors may account for this. Many of the mammalian Ig receptors and cadherins associate with each other, and multivalent interactions within these complexes may require removal of multiple components to reveal dramatic defects in vivo. Nevertheless, it is possible that the murine adhesion receptors rate-limiting in vivo have not yet been identified or fully assessed.

Krauss, Robert S., E-mail: Robert.Krauss@mssm.edu [Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, NY 10029 (United States)

2010-11-01

278

Formation of microvilli and phosphorylation of ERM family proteins by CD43, a potent inhibitor for cell adhesion  

PubMed Central

CD43/sialophorin/leukosialin, a common leukocyte antigen, is known as an inhibitor for cell adhesion. The ectodomain of CD43 is considered as a molecular barrier for cell adhesion, while the cytoplasmic domain has a binding site for Ezrin/Radixin/Moesin (ERM). We found expression of CD43 induced cell rounding, inhibition of cell re-attachment, augmentation of microvilli and phosphorylation of ERM in HE K293T cells. Mutant studies revealed the ectodomain of CD43, but not the intracellular domain, essential and sufficient for all these phenomena. We also found that forced cell detachment by itself induced phosphorylation of ERM in HE K293T cells. Taken together, these findings indicate that inhibition of cell adhesion by the ectodomain of CD43 induces phosphorylation of ERM, microvilli formation and eventual cell rounding. Furthermore, our study suggests a novel possibility that cell detachment itself induces activation of ERM and modification of cell shape. PMID:21045567

Yamane, Junko; Ohnishi, Hiroe; Sasaki, Hiroyuki; Narimatsu, Hisashi; Ohgushi, Hajime

2011-01-01

279

Protein kinase C?/? inhibitor Gö6976 promotes PC12 cell adhesion and spreading through membrane recruitment and activation of protein kinase C?.  

PubMed

Gö6976 is a nonglycosidic indolocarbazole compound widely used as a specific inhibitor of PKC?/?. In experiments probing for a role of PKC? in human laminin-2-integrin-mediated cell adhesion and spreading of PC12 cells, we observed unexpected enhancements of adhesion, spreading and stress fiber formation to 1 ?M Gö6976 with concomitant increase in membrane translocation of PKC? and autophosphorylation of focal adhesion kinase (FAK). Importantly, enhanced cellular behavior and membrane translocation of PKC? induced by Gö6976 was retained in siRNA-transfected PC12 cells to knockdown PKC? expression. Gö6976 also induced laminin-dependent cell adhesion in NIH/3T3 and CV-1 fibroblasts, suggesting of a mechanism that may be common to multiple cell-types. A specific inhibitor of PKC?, rottlerin, completely abrogated Gö6976-dependent increase in PC12 cell adhesion to laminin as well as the activation of small GTPases, Rac1 and Cdc42, that are downstream of PKC? in adhesion receptor signaling. siRNA knockdown of Rac1 and Cdc42 expression inhibited cell spreading and lamellipodia formation in PC12 cells. Overall, these results suggest that Gö6976 may stimulate membrane recruitment of PKC? through a mechanism that is independent of PKC?/? signaling. In addition, the activation of Rac1 and Cdc42 by human laminin-2-integrin-dependent activation of PKC?/FAK signaling mediates cell spreading and lamellipodia formation in PC12 cells. PMID:23063429

Jung, Sung Youn; Kim, O Bok; Kang, Hyun Ki; Jang, Da Hyun; Min, Byung-Moo; Yu, Frank H

2013-02-01

280

Overexpression of Camello, a Member of a Novel Protein Family, Reduces Blastomere Adhesion and Inhibits Gastrulation in Xenopus laevis  

Microsoft Academic Search

Vertebrate gastrulation involves complex coordinated movements of cells and cell layers to establish the axial structures and the general body plan. Adhesion molecules and the components of extracellular matrix were shown to be involved in this process. However, other participating molecules and detailed mechanisms of the control of gastrulation movements remain largely unknown. Here, we describe a novel Xenopus gene

Anna E. Popsueva; Natalia N. Luchinskaya; Anastasia V. Ludwig; Olga Y. Zinovjeva; Dmitry A. Poteryaev; Marina M. Feigelman; Maxim B. Ponomarev; Lubov Berekelya; Alexander V. Belyavsky

2001-01-01

281

Freeze-dried allograft-mediated gene or protein delivery of growth and differentiation factor 5 reduces reconstructed murine flexor tendon adhesions  

PubMed Central

Advances in allograft processing have opened new horizons for clinical adaptation of flexor tendon allografts as delivery scaffolds for antifibrotic therapeutics. Recombinant adeno-associated-virus (rAAV) gene delivery of the growth and differentiation factor 5 (GDF-5) has been previously associated with antifibrotic effects in a mouse model of flexor tendoplasty. In this study, we compared the effects of loading freeze-dried allografts with different doses of GDF-5 protein or rAAV-Gdf5 on flexor tendon healing and adhesions. We first optimized the protein and viral loading parameters using reverse transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and in vivo bioluminescent imaging. We then reconstructed flexor digitorum longus (FDL) tendons of the mouse hindlimb with allografts loaded with low and high doses of recombinant GDF-5 protein and rAAV-Gdf5 and evaluated joint flexion and biomechanical properties of the reconstructed tendon. In vitro optimization studies determined that both the loading time and concentration of the growth factor and viral vector had dose-dependent effects on their retention on the freeze-dried allograft. In vivo data suggest that protein and gene delivery of GDF-5 had equivalent effects on improving joint flexion function, in the range of doses used. Within the doses tested, the lower doses of GDF-5 had more potent effects on suppressing adhesions without adversely affecting the strength of the repair. These findings indicate equivalent antifibrotic effects of Gdf5 gene and protein delivery, but suggest that localized delivery of this potent factor should also carefully consider the dosage used to eliminate untoward effects, regardless of the delivery mode. PMID:24812579

Hasslund, Sys; Dadali, Tulin; Ulrich-Vinther, Michael; Søballe, Kjeld; Schwarz, Edward M

2014-01-01

282

Small peptides derived from somatotropin domain-containing proteins inhibit blood and lymphatic endothelial cell proliferation, migration, adhesion and tube formation  

PubMed Central

Angiogenesis is thoroughly balanced and regulated in health; however, it is dysregulated in many diseases including cancer, age-related macular degeneration, cardiovascular diseases such as coronary and peripheral artery diseases and stroke, abnormal embryonic development, and abnormal wound healing. In addition to angiogenesis, lymphangiogenesis is pivotal for maintaining the immune system, homeostasis of body fluids and lymphoid organs; dysregulated lymphangiogenesis may cause inflammatory diseases and lymph node mediated tumor metastasis. Anti-angiogenic or anti-lymphangiogenic small peptides may play an important role as therapeutic agents normalizing angiogenesis or lymphangiogenesis in disease conditions. Several novel endogenous peptides derived from proteins containing a conserved somatotropin domain have been previously identified with the help of our bioinformatics-based methodology. These somatotropin peptides were screened for inhibition of angiogenesis and lymphangiogenesis using in vitro proliferation, migration, adhesion and tube formation assays with blood and lymphatic endothelial cells. We found that the peptides have the potential for inhibiting both angiogenesis and lymphangiogenesis. Focusing the study on the inhibition of lymphangiogenesis, we found that a peptide derived from the somatotropin conserved domain of transmembrane protein 45A human was the most potent lymphangiogenesis inhibitor, blocking lymphatic endothelial cell migration, adhesion, and tube formation. PMID:21920451

Lee, Esak; Rosca, Elena V.; Pandey, Niranjan B.; Popel, Aleksander S.

2011-01-01

283

Cell adhesion as a novel approach to determining the cellular binding motif on the severe acute respiratory syndrome coronavirus spike protein.  

PubMed

Emerging life threatening pathogens such as severe acute aspiratory syndrome-coronavirus (SARS-CoV), avian-origin influenzas H7N9, and the Middle East respiratory syndrome coronavirus (MERS-CoV) have caused a high case-fatality rate and psychological effects on society and the economy. Therefore, a simple, rapid, and safe method to investigate a therapeutic approach against these pathogens is required. In this study, a simple, quick, and safe cell adhesion inhibition assay was developed to determine the potential cellular binding site on the SARS-CoV spike protein. Various synthetic peptides covering the potential binding site helped to minimize further the binding motif to 10-25 residues. Following analyses, 2 peptides spanning the 436-445 and 437-461 amino acids of the spike protein were identified as peptide inhibitor or peptide vaccine candidates against SARS-CoV. PMID:24530430

Chang, Hsin-Hou; Chen, Po-Kong; Lin, Guan-Ling; Wang, Chun-Jen; Liao, Chih-Hsien; Hsiao, Yu-Cheng; Dong, Jing-Hua; Sun, Der-Shan

2014-06-01

284

Antibodies Specific for the High-Molecular-Weight Adhesion Proteins of Nontypeable Haemophilus influenzae Are Opsonophagocytic for both Homologous and Heterologous Strains?  

PubMed Central

The HMW1/HMW2-like adhesion proteins of nontypeable Haemophilus influenzae (NTHI) are expressed by 75% of NTHI strains. Antibodies directed against these proteins are opsonophagocytic in vitro and are protective in an animal model of infection. The objective of the present study was to determine the opsonophagocytic activity of high-titer anti-HMW1/HMW2 immune sera against both homologous and heterologous NTHI strains. Chinchillas were immunized with purified HMW1/HMW2-like proteins from five prototype NTHI strains. Serum opsonophagocytic activity was monitored in an assay that uses a human promyelocytic cell line, HL-60, as the source of phagocytic cells. Preimmune sera did not demonstrate opsonophagocytic killing of any strains. In contrast, the immune sera demonstrated killing of the five homologous NTHI strains at titers ranging from 1:320 to 1:640. The immune sera also demonstrated killing of eight heterologous NTHI strains that express HMW1/HMW2-like proteins at titers ranging from 0 to 1:640. Killing of heterologous strains sometimes demonstrated a prozone phenomenon. None of the immune sera killed NTHI strains that did not express HMW1/HMW2-like proteins. Adsorption of immune sera with HMW1/HMW2-like proteins purified from either homologous or heterologous NTHI strains eliminated opsonophagocytic killing of homologous strains in most cases. These data demonstrate that antibodies produced following immunization with the HMW1/HMW2-like proteins are opsonophagocytic for both homologous and heterologous NTHI and strongly suggest that common epitopes recognized by functionally active antibodies exist on the HMW1/HMW2-like proteins of unrelated NTHI strains. The results argue for the continued investigation of the HMW1/HMW2-like proteins as potential vaccine candidates for the prevention of NTHI disease. PMID:17021246

Winter, Linda E.; Barenkamp, Stephen J.

2006-01-01

285

Identification of a new isoform of cell-cell adhesion molecule 105 (C-CAM), C-CAM4: a secretory protein with only one Ig domain.  

PubMed

A series of Southern blot hybridization experiments using probes derived from different regions of the rat liver cell-cell adhesion molecule 105 (C-CAM) cDNA revealed the presence of a 9.6 kb EcoRI genomic fragment that seemed to encode a unique C-CAM isoform. An RNase protection study showed that this c-CAM transcript was expressed in placenta, spleen, lung and large intestine. In contrast, the other C-CAM isoforms, C-CAM1 and C-CAM2, are expressed in liver and small intestine. This result also suggests that the new isoform, which we named C-CAM4, was indeed encoded by a new C-CAM gene. A rat placenta cDNA library was then screened and the full-length cDNA coding for C-CAM4 was isolated. The deduced protein contained 142 amino acids and had a calculated molecular mass of 15 kDa. C-CAM4 was composed of a leader sequence and the first V-like Ig domain typical of C-CAM-family proteins. However, C-CAM4 lacked the C-like Ig domains, the transmembrane domain, and the cytoplasmic domain found in other C-CAM isoforms. Thus, C-CAM4 is different from the other known C-CAMs in that it is a secreted protein. We have previously shown that the first Ig domain of C-CAM1 is crucial for its adhesion function. The V-like Ig domain of C-CAM4 had 92% and 89% sequence identity with the corresponding regions of C-CAM1 and C-cam2 respectively. Together these results suggest that C-CAM4 may play a role in regulating the function of other C-CAM family proteins. PMID:8645160

Earley, K; Luo, W; Qiu, Y; Thompson, N L; Chou, J; Hixson, D C; Lin, S H

1996-05-01

286

Identification of a new isoform of cell-cell adhesion molecule 105 (C-CAM), C-CAM4: a secretory protein with only one Ig domain.  

PubMed Central

A series of Southern blot hybridization experiments using probes derived from different regions of the rat liver cell-cell adhesion molecule 105 (C-CAM) cDNA revealed the presence of a 9.6 kb EcoRI genomic fragment that seemed to encode a unique C-CAM isoform. An RNase protection study showed that this c-CAM transcript was expressed in placenta, spleen, lung and large intestine. In contrast, the other C-CAM isoforms, C-CAM1 and C-CAM2, are expressed in liver and small intestine. This result also suggests that the new isoform, which we named C-CAM4, was indeed encoded by a new C-CAM gene. A rat placenta cDNA library was then screened and the full-length cDNA coding for C-CAM4 was isolated. The deduced protein contained 142 amino acids and had a calculated molecular mass of 15 kDa. C-CAM4 was composed of a leader sequence and the first V-like Ig domain typical of C-CAM-family proteins. However, C-CAM4 lacked the C-like Ig domains, the transmembrane domain, and the cytoplasmic domain found in other C-CAM isoforms. Thus, C-CAM4 is different from the other known C-CAMs in that it is a secreted protein. We have previously shown that the first Ig domain of C-CAM1 is crucial for its adhesion function. The V-like Ig domain of C-CAM4 had 92% and 89% sequence identity with the corresponding regions of C-CAM1 and C-cam2 respectively. Together these results suggest that C-CAM4 may play a role in regulating the function of other C-CAM family proteins. PMID:8645160

Earley, K; Luo, W; Qiu, Y; Thompson, N L; Chou, J; Hixson, D C; Lin, S H

1996-01-01

287

A biologically active sequence of the laminin alpha2 large globular 1 domain promotes cell adhesion through syndecan-1 by inducing phosphorylation and membrane localization of protein kinase Cdelta.  

PubMed

Laminin-2 promotes basement membrane assembly and peripheral myelinogenesis; however, a receptor-binding motif within laminin-2 and the downstream signaling pathways for motif-mediated cell adhesion have not been fully established. The human laminin-2 alpha2 chain cDNAs cloned from human keratinocytes and fibroblasts correspond to the laminin alpha2 chain variant sequence from the human brain. Individually expressed recombinant large globular (LG) 1 protein promotes cell adhesion and has heparin binding activities. Studies with synthetic peptides delineate the DLTIDDSYWYRI motif (Ln2-P3) within the LG1 as a major site for both heparin and cell binding. Cell adhesion to LG1 and Ln2-P3 is inhibited by treatment of heparitinase I and chondroitinase ABC. Syndecan-1 from PC12 cells binds to LG1 and Ln2-P3 and colocalizes with both molecules. Suppression of syndecan-1 with RNA interference inhibits cell adhesion to LG1 and Ln2-P3. The binding of syndecan-1 with LG1 and Ln2-P3 induces the recruitment of protein kinase Cdelta (PKCdelta) into the membrane and stimulates its tyrosine phosphorylation. A decrease in PKCdelta activity significantly reduces cell adhesion to LG1 and Ln2-P3. Taken together, these results indicate that the Ln2-P3 motif and LG1 domain, containing the motif, within the human laminin-2 alpha2 chain are major ligands for syndecan-1, which mediates cell adhesion through the PKCdelta signaling pathway. PMID:19762914

Jung, Sung Youn; Kim, Jin-Man; Kang, Hyun Ki; Jang, Da Hyun; Min, Byung-Moo

2009-11-13

288

CPNA-1, a copine domain protein, is located at integrin adhesion sites and is required for myofilament stability in Caenorhabditis elegans  

PubMed Central

We identify cpna-1 (F31D5.3) as a novel essential muscle gene in the nematode Caenorhabditis elegans. Antibodies specific to copine domain protein atypical-1 (CPNA-1), as well as a yellow fluorescent protein translational fusion, are localized to integrin attachment sites (M-lines and dense bodies) in the body-wall muscle of C. elegans. CPNA-1 contains an N-terminal predicted transmembrane domain and a C-terminal copine domain and binds to the M-line/dense body protein PAT-6 (actopaxin) and the M-line proteins UNC-89 (obscurin), LIM-9 (FHL), SCPL-1 (SCP), and UNC-96. Proper CPNA-1 localization is dependent upon PAT-6 in embryonic and adult muscle. Nematodes lacking cpna-1 arrest elongation at the twofold stage of embryogenesis and display disruption of the myofilament lattice. The thick-filament component myosin heavy chain MYO-3 and the M-line component UNC-89 are initially localized properly in cpna-1–null embryos. However, in these embryos, when contraction begins, MYO-3 and UNC-89 become mislocalized into large foci and animals die. We propose that CPNA-1 acts as a linker between an integrin-associated protein, PAT-6, and membrane-distal components of integrin adhesion complexes in the muscle of C. elegans. PMID:23283987

Warner, Adam; Xiong, Ge; Qadota, Hiroshi; Rogalski, Teresa; Vogl, A. Wayne; Moerman, Donald G.; Benian, Guy M.

2013-01-01

289

Cadherin-Dependent Cell Morphology in an Epithelium: Constructing a Quantitative Dynamical Model  

PubMed Central

Cells in the Drosophila retina have well-defined morphologies that are attained during tissue morphogenesis. We present a computer simulation of the epithelial tissue in which the global interfacial energy between cells is minimized. Experimental data for both normal cells and mutant cells either lacking or misexpressing the adhesion protein N-cadherin can be explained by a simple model incorporating salient features of morphogenesis that include the timing of N-cadherin expression in cells and its temporal relationship to the remodeling of cell-cell contacts. The simulations reproduce the geometries of wild-type and mutant cells, distinguish features of cadherin dynamics, and emphasize the importance of adhesion protein biogenesis and its timing with respect to cell remodeling. The simulations also indicate that N-cadherin protein is recycled from inactive interfaces to active interfaces, thereby modulating adhesion strengths between cells. PMID:21814505

Gemp, Ian M.; Carthew, Richard W.; Hilgenfeldt, Sascha

2011-01-01

290

Effect of the knockdown of death-associated protein 1 expression on cell adhesion, growth and migration in breast cancer cells.  

PubMed

Death-associated protein 1 (DAP1) is a highly conserved phosphoprotein involved in the regulation of autophagy. A previous clinical study by our group suggested an association between low DAP1 expression and clinicopathological parameters of human breast cancer. In the present study, we aimed to determine the role of DAP1 in cancer cell behaviour in the context of human breast cancer. We developed knockdown sublines of MCF7 and MDA-MB?231, and performed growth, adhesion and invasion assays and electric cell-substrate impedance sensing (ECIS) studies of the post-wound migration of cells. In addition, we studied the mRNA expression of caspase 8 and 9, DELE, IPS1, cyclin D1 and p21 in the control and knockdown sublines. Knockdown was associated with increased adhesion and migration, significantly so in the MDA-MB-231DAP1kd cell subline (p=0.029 and p=0.001, respectively). Growth in MCF7 cells showed a significant suppression on day 3 (p=0.029), followed by an increase in growth matching the controls on day 5. While no change in the apoptotic response to serum starvation could be attributed to DAP1 knockdown, the expression of known components of the apoptosis pathway (caspase 8) and cell cycle (p21) was significantly reduced in the MCF7DAP1kd cell subline (p?0.05), while in MDA-MB-231DAP1kd the expression of a pro-apoptotic molecule, IPS1, was suppressed (p?0.05). DAP1 may have an important role in cell adhesion, migration and growth in the context of breast cancer and has significant associations with the apoptosis pathway. Furthermore, we believe that delayed increase in growth observed in the MCF7DAP1kd cell subline may indicate activation of a strongly pro-oncogenic pathway downstream of DAP1. PMID:25530065

Wazir, Umar; Sanders, Andrew J; Wazir, Ali; Baig, Ruqia Mehmood; Jiang, Wen G; Ster, Irina C; Sharma, Anup K; Mokbel, Kefah

2015-03-01

291

Cellular Settings Mediating Src Substrate Switching between Focal Adhesion Kinase Tyrosine 861 and CUB-domain-containing protein 1 (CDCP1) Tyrosine 734*  

PubMed Central

Reciprocal interactions between Src family kinases (SFKs) and focal adhesion kinase (FAK) are critical during changes in cell attachment. Recently it has been recognized that another SFK substrate, CUB-domain-containing protein 1 (CDCP1), is differentially phosphorylated during these events. However, the molecular processes underlying SFK-mediated phosphorylation of CDCP1 are poorly understood. Here we identify a novel mechanism in which FAK tyrosine 861 and CDCP1-Tyr-734 compete as SFK substrates and demonstrate cellular settings in which SFKs switch between these sites. Our results show that stable CDCP1 expression induces robust SFK-mediated phosphorylation of CDCP1-Tyr-734 with concomitant loss of p-FAK-Tyr-861 in adherent HeLa cells. SFK substrate switching in these cells is dependent on the level of expression of CDCP1 and is also dependent on CDCP1-Tyr-734 but is independent of CDCP1-Tyr-743 and -Tyr-762. In HeLa CDCP1 cells, engagement of SFKs with CDCP1 is accompanied by an increase in phosphorylation of Src-Tyr-416 and a change in cell morphology to a fibroblastic appearance dependent on CDCP1-Tyr-734. SFK switching between FAK-Tyr-861 and CDCP1-Tyr-734 also occurs during changes in adhesion of colorectal cancer cell lines endogenously expressing these two proteins. Consistently, increased p-FAK-Tyr-861 levels and a more epithelial morphology are seen in colon cancer SW480 cells silenced for CDCP1. Unlike protein kinase C?, FAK does not appear to form a trimeric complex with Src and CDCP1. These data demonstrate novel aspects of the dynamics of SFK-mediated cell signaling that may be relevant during cancer progression. PMID:21994943

Wortmann, Andreas; He, Yaowu; Christensen, Melinda E.; Linn, MayLa; Lumley, John W.; Pollock, Pamela M.; Waterhouse, Nigel J.; Hooper, John D.

2011-01-01

292

The Orphan Adhesion G Protein-coupled Receptor GPR97 Regulates Migration of Lymphatic Endothelial Cells via the Small GTPases RhoA and Cdc42*  

PubMed Central

The important role of the lymphatic vascular system in pathological conditions such as inflammation and cancer has been increasingly recognized, but its potential as a pharmacological target is poorly exploited. Our study aimed at the identification and molecular characterization of lymphatic-specific G protein-coupled receptors (GPCRs) to assess new targets for pharmacological manipulation of the lymphatic vascular system. We used a TaqMan quantitative RT-PCR-based low density array to determine the GPCR expression profiles of ex vivo isolated intestinal mouse lymphatic (LECs) and blood vascular endothelial cells (BECs). GPR97, an orphan adhesion GPCR of unknown function, was the most highly and specifically expressed GPCR in mouse lymphatic endothelium. Using siRNA silencing, we found that GPR97-deficient primary human LECs displayed increased adhesion and collective cell migration, whereas single cell migration was decreased as compared with nontargeting siRNA-transfected control LECs. Loss of GPR97 shifted the ratio of active Cdc42 and RhoA and initiated cytoskeletal rearrangements, including F-actin redistribution, paxillin and PAK4 phosphorylation, and ?1-integrin activation. Our data suggest a possible role of GPR97 in lymphatic remodeling and furthermore provide the first insights into the biological functions of GPR97. PMID:24178298

Valtcheva, Nadejda; Primorac, Adriana; Jurisic, Giorgia; Hollmén, Maija; Detmar, Michael

2013-01-01

293

C-reactive protein and soluble vascular cell adhesion molecule-1 are associated with elevated urinary albumin excretion but do not explain its link with cardiovascular risk.  

PubMed

An elevated urinary albumin excretion rate (UAER) is associated with an increased risk of cardiovascular mortality, but the pathophysiological mechanism underlying this association is poorly understood. To investigate the role of endothelial dysfunction, leukocyte adhesion, and low-grade inflammation (1) in the development of elevated UAER (study I) and (2) in linking elevated UAER with risk of cardiovascular mortality (study II), we performed a prospective study in an age-, sex-, and glucose tolerance- stratified sample of a population-based cohort aged 50 to 75 years. High levels of von Willebrand factor, soluble vascular cell adhesion molecule-1 (sVCAM-1), and C-reactive protein (CRP) were used as markers of endothelial dysfunction, leukocyte adhesion, and low-grade inflammation, respectively. For study I, subjects who had normal UAER at baseline (n=316 subjects, 66 with type 2 diabetes) were reexamined after a mean follow-up of 6.1 years. The development of elevated UAER was defined as a mean albumin-to-creatinine ratio >2.0 mg/mmol at follow-up. Age-, sex-, and glucose tolerance- adjusted logistic regression analyses showed the development of elevated UAER to be significantly associated with levels of sVCAM-1 and CRP (odds ratio 1.14 [95% CI 1.02 to 1.27] per 10% increase of sVCAM-1 and odds ratio 1.17 [95% CI 1.04 to 1.32] per 50% increase of CRP). The results were not materially different after additional adjustment for hypertension, body mass index, cardiovascular disease, and creatinine clearance or stratification by the presence of diabetes. For study II, the vital status of all subjects (n= 575) was determined after a mean follow-up of 6.6 years. Eighty-one of 575 subjects died (30 died of cardiovascular disease). The presence of elevated UAER at baseline was associated with a 4.1-fold (1.94 to 8.73) increased risk of cardiovascular death after adjustment for age, sex, and glucose tolerance status. Adjustment for levels of von Willebrand factor, sVCAM-1, or CRP did not materially affect the results, nor did additional adjustment for the presence of hypertension, retinopathy, and cardiovascular disease and for levels of homocysteine, triglycerides, and high density lipoprotein cholesterol. Leukocyte adhesion (sVCAM-1) and low-grade inflammation (CRP) are determinants of the development of elevated UAER. However, these determinants do not explain the association between elevated UAER and cardiovascular mortality. PMID:11950696

Jager, Agnes; van Hinsbergh, Victor W M; Kostense, Piet J; Emeis, Jef J; Nijpels, Giel; Dekker, Jacqueline M; Heine, Robert J; Bouter, Lex M; Stehouwer, Coen D A

2002-04-01

294

Neutrophil-Activating Protein Mediates Adhesion of Helicobacter pylori to Sulfated Carbohydrates on High-Molecular-Weight Salivary Mucin  

PubMed Central

The in vitro binding of surface-exposed material and outer membrane proteins of Helicobacter pylori to high-molecular-weight salivary mucin was studied. We identified a 16-kDa surface protein which adhered to high-molecular-weight salivary mucin. This protein binds specifically to sulfated oligosaccharide structures such as sulfo-Lewis a, sulfogalactose and sulfo-N-acetyl-glucosamine on mucin. Sequence analysis of the protein proved that it was identical to the N-terminal amino acid sequence of neutrophil-activating protein. Moreover, this adhesin was able to bind to Lewis x blood group antigen. PMID:9453593

Namavar, Ferry; Sparrius, Marion; Veerman, Enno C. I.; Appelmelk, Ben J.; Vandenbroucke-Grauls, Christina M. J. E.

1998-01-01

295

Natural Underwater Adhesives  

PubMed Central

The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent curing. PMID:21643511

Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

2011-01-01

296

Adhesion molecules and transplantation.  

PubMed Central

OBJECTIVE: Accessory adhesion molecules are thought to influence the first interaction between host leukocytes and graft vascular endothelial cells. Their role in transplantation is reviewed. SUMMARY: Adhesion molecules have been divided into three major families: the selectins, the integrins, and the immunoglobulin superfamily. Selectins are small proteins that mediate the first contact between stimulated endothelial cells and leukocytes. Integrins interact with cytoskeletal components of cells, presumably coordinating extracellular stimuli with cytoskeleton dependent actions, such as motility, shape change, and phagocytic responses. Members of the immunoglobulin superfamily are structurally homologous, although they do not necessarily share similar functions. They are involved in T-cell proliferation and intracellular events. METHODS: Various groups of investigators have studied the influence and expression of adhesion molecules following transplantation. The authors of this article have reviewed and summarized the available literature. RESULTS: Many different adhesion molecules are up-regulated during the rejection event. Treatment of transplant recipients with monoclonal antibodies against accessory molecules, such as leukocyte function associated antigen 1 (LFA-1) and intercellular adhesion molecule 1 (ICAM-1), has resulted in either a prolongation of transplant survival or the induction of tolerance in some models. Other interventions are under study. CONCLUSION: By mediating the initial leukocyte/endothelial cell interactions, adhesion molecules may play an important role in graft rejection, mediation of infiltration into the graft, and dissemination of the antigenic message to the lymphoid tissues of the host. Future studies will have to deal not only with conceptualizing their function and mechanisms of action, but also with manipulating their interrelationships to the benefit of the graft recipient. PMID:8297174

Heemann, U W; Tullius, S G; Azuma, H; Kupiec-Weglinsky, J; Tilney, N L

1994-01-01

297

Human Monocytes Bind to Two Cytokine-Induced Adhesive Ligands on Cultured Human Endothelial Cells: Endothelial-Leukocyte Adhesion Molecule1 and Vascular Cell Adhesion Molecule1  

Microsoft Academic Search

Vascular cell adhesion molecule-1 (VCAM-1) and endothelial- leukocyte adhesion molecule-1 (ELAM-I) are adhesive pro- teins induced on endothelium by cytokines. We examined the contribution of these adhesive proteins to human peripheral blood monocyte adherence to endothelium using transfected Chinese hamster ovary (CHO) cells stably expressing these proteins and monoclonal antibodies (MoAbs) to ELAM-I, VCAM-1, or CD49d\\/CD29 (VLA-4). the leukocyte receptor

T. Carlos; N. Kovach; M. Rosa; E. Wayner; C. Benjamin; L. Osborn; R. Lobb; J. Harlan

1991-01-01

298

West Nile virus infection modulates human brain microvascular endothelial cells tight junction proteins and cell adhesion molecules: Transmigration across the in vitro blood-brain barrier  

PubMed Central

Neurological complications such as inflammation, failure of the blood-brain barrier (BBB), and neuronal death contribute to the mortality and morbidity associated with WNV-induced meningitis. Compromised BBB indicates the ability of the virus to gain entry into the CNS via the BBB, however, the underlying mechanisms, and the specific cell types associated with WNV-CNS trafficking are not well understood. Brain microvascular endothelial cells, main component of the BBB, represent a barrier to virus dissemination into the CNS and could play key role in WNV spread via hematogenous route. To investigate WNV entry into the CNS, we infected primary human brain microvascular endothelial (HBMVE) cells with the neurovirulent strain of WNV (NY99) and examined WNV replication kinetics together with the changes in the expressions of key tight junction proteins (TJP) and cell adhesion molecules (CAM). WNV infection of HBMVE cells was productive as analyzed by plaque assay and qRT-PCR, and did not induce cytopathic effect. Increased mRNA and protein expressions of TJP (claudin-1) and CAM (vascular cell adhesion molecule and E-selectin) were observed at days 2 and 3 after infection, respectively, which coincided with the peak in WNV replication. Further, using an in vitro BBB model comprised of HBMVE cells, we demonstrate that cell-free WNV can cross the BBB, without compromising the BBB integrity. These data suggest that infection of HBMVE cells can facilitate entry of cell-free virus into the CNS without disturbing the BBB, and increased CAM may assist in the trafficking of WNV-infected immune cells into the CNS, via ‘Trojan horse’ mechanism, thereby contributing to WNV dissemination in the CNS and associated pathology. PMID:19135695

Verma, Saguna; Lo, Yeung; Chapagain, Moti; Lum, Stephanie; Kumar, Mukesh; Gurjav, Ulziijargal; Luo, Haiyan; Nakatsuka, Austin; Nerurkar, Vivek R.

2009-01-01

299

Knockdown of Y?box?binding protein?1 inhibits the malignant progression of HT?29 colorectal adenocarcinoma cells by reversing epithelial?mesenchymal transition.  

PubMed

Y?box binding protein?1 (YB?1) has been identified as an oncoprotein in various malignancies. The aim of this study was to investigate the biological role of YB?1 and its association with epithelial?to?mesenchymal transition (EMT) in colorectal cancer (CRC). The expression of YB?1 and three EMT?related proteins (E?cadherin, N?cadherin and vimentin) was analyzed in 80 CRC and matched normal tissue samples, by immunohistochemistry. The results indicated that the expression of YB?1 was higher in CRC tissue samples than that in matched normal controls and was significantly correlated with tumor differentiation, tumor invasion, lymph node metastasis and distant metastases. Furthermore, analysis showed that YB?1 expression was negatively correlated with E?cadherin and positively correlated with N?cadherin and vimentin expression. In vitro assays showed that knockdown of YB?1 inhibited the proliferation, apoptosis resistance, invasion and migration of the HT?29 CRC cell line. Of note, following knockdown of YB?1, E?cadherin expression was elevated whereas N?cadherin and vimentin expression was reduced. Taken together, these results suggest that YB?1 promotes the malignant progression of CRC in part through the induction of EMT, and YB?1 may therefore be a potential novel target for CRC treatment. PMID:25201740

Yan, Xue-Bing; Zhu, Qing-Chao; Chen, Hong-Qi; Peng, Jia-Yuan; Chao, Hong-Lei; Du, Hang-Xiang; Wang, Zhi-Gang; Jin, Zhi-Ming

2014-11-01

300

Evaluation of recombinant HP6-Tsag, an 18 kDa Taenia saginata oncospheral adhesion protein, for the diagnosis of cysticercosis.  

PubMed

With the objective of providing inexpensive and reproducible assays for the detection of antibodies indicating exposure to Taenia saginata and Taenia solium, we have evaluated the diagnostic utility of the T. saginata oncosphere adhesion protein (HP6-Tsag), expressed in baculovirus (HP6-Bac) and bacteria (HP6-GST [glutathione S-transferase]), employing enzyme-linked immunosorbent assays (ELISAs) and sera from T. saginata infected cattle, T. solium infected pigs and serum and cerebrospinal fluid (CSF) samples from clinically defined T. solium neurocysticercosis (NCC) patients. The two recombinant proteins were antigenic in all three systems, with the signal to background ratio of the HP6-Bac ELISA slightly higher than that for the HP6-GST ELISA. Assay performance in cattle was similar to previously described peptide-based ELISA assays, although NCC sample sensitivity/specificity was marginally better. The sensitivity of the HP6-Bac and HP6-GST ELISAs was close for active human NCC (77.4 and 80.6% for serum and 76.9 and 73.1% for CSF samples, respectively). In inactive human NCC, however, the sensitivity of the HP6-Bac ELISA was almost twice that of the HP6-GST ELISA. Because peptides are relatively expensive and recombinant proteins are simple and economical to produce, the latter may provide useful reagents for antibody detection in countries with endemic cysticercosis/NCC. PMID:17351832

Ferrer, Elizabeth; González, Luís Miguel; Martínez-Escribano, José Angel; González-Barderas, María Eugenia; Cortéz, María Milagros; Dávila, Iris; Harrison, Leslie J S; Parkhouse, R Michael E; Gárate, Teresa

2007-08-01

301

A novel O-linked glycan modulates Campylobacter jejuni major outer membrane protein-mediated adhesion to human histo-blood group antigens and chicken colonization  

PubMed Central

Campylobacter jejuni is an important cause of human foodborne gastroenteritis; strategies to prevent infection are hampered by a poor understanding of the complex interactions between host and pathogen. Previous work showed that C. jejuni could bind human histo-blood group antigens (BgAgs) in vitro and that BgAgs could inhibit the binding of C. jejuni to human intestinal mucosa ex vivo. Here, the major flagella subunit protein (FlaA) and the major outer membrane protein (MOMP) were identified as BgAg-binding adhesins in C. jejuni NCTC11168. Significantly, the MOMP was shown to be O-glycosylated at Thr268; previously only flagellin proteins were known to be O-glycosylated in C. jejuni. Substitution of MOMP Thr268 led to significantly reduced binding to BgAgs. The O-glycan moiety was characterized as Gal(?1–3)-GalNAc(?1–4)-GalNAc(?1–4)-GalNAc?1-Thr268; modelling suggested that O-glycosylation has a notable effect on the conformation of MOMP and this modulates BgAg-binding capacity. Glycosylation of MOMP at Thr268 promoted cell-to-cell binding, biofilm formation and adhesion to Caco-2 cells, and was required for the optimal colonization of chickens by C. jejuni, confirming the significance of this O-glycosylation in pathogenesis. PMID:24451549

Mahdavi, Jafar; Pirinccioglu, Necmettin; Oldfield, Neil J.; Carlsohn, Elisabet; Stoof, Jeroen; Aslam, Akhmed; Self, Tim; Cawthraw, Shaun A.; Petrovska, Liljana; Colborne, Natalie; Sihlbom, Carina; Borén, Thomas; Wooldridge, Karl G.; Ala'Aldeen, Dlawer A. A.

2014-01-01

302

Cbf11 and Cbf12, the fission yeast CSL proteins, play opposing roles in cell adhesion and coordination of cell and nuclear division  

SciTech Connect

The CSL (CBF1/RBP-J{kappa}/Suppressor of Hairless/LAG-1) family is comprised of transcription factors essential for metazoan development, mostly due to their involvement in the Notch receptor signaling pathway. Recently, we identified two novel classes of CSL genes in the genomes of several fungal species, organisms lacking the Notch pathway. In this study, we characterized experimentally cbf11{sup +} and cbf12{sup +}, the two CSL genes of Schizosaccharomyces pombe, in order to elucidate the CSL function in fungi. We provide evidence supporting their identity as genuine CSL genes. Both cbf11{sup +} and cbf12{sup +} are non-essential; they have distinct expression profiles and code for nuclear proteins with transcription activation potential. Significantly, we demonstrated that Cbf11 recognizes specifically the canonical CSL response element GTG{sup A}/{sub G}GAA in vitro. The deletion of cbf11{sup +} is associated with growth phenotypes and altered colony morphology. Furthermore, we found that Cbf11 and Cbf12 play opposite roles in cell adhesion, nuclear and cell division and their coordination. Disturbed balance of the two CSL proteins leads to cell separation defects (sep phenotype), cut phenotype, and high-frequency diploidization in heterothallic strains. Our data show that CSL proteins operate in an organism predating the Notch pathway, which should be of relevance to the understanding of (Notch-independent) CSL functions in metazoans.

Prevorovsky, Martin; Grousl, Tomas; Stanurova, Jana; Rynes, Jan [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic)] [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic); Nellen, Wolfgang [Department of Genetics, Kassel University, Heinrich Plett Strasse 40, 34132 Kassel (Germany)] [Department of Genetics, Kassel University, Heinrich Plett Strasse 40, 34132 Kassel (Germany); Puta, Frantisek [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic)] [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic); Folk, Petr, E-mail: folk@natur.cuni.cz [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic)] [Department of Cell Biology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 43, Prague 2 (Czech Republic)

2009-05-01

303

The C. elegans EMAP-like protein, ELP-1 is required for touch sensation and associates with microtubules and adhesion complexes  

PubMed Central

Background The founding member of the EMAP-like protein family is the Echinoderm Microtubule-Associated Protein (EMAP), so-named for its abundance in sea urchin, starfish, and sand dollar eggs. The EMAP-like protein family has five members in mammals (EML1 through EML5) and only one in both Drosophila (ELP-1) and C. elegans (ELP-1). Biochemical studies of sea urchin EMAP and vertebrate EMLs implicate these proteins in the regulation of microtubule stability. So far, however, the physiological function of this protein family remains unknown. Results We examined the expression pattern of C. elegans ELP-1 by means of transgenic gene expression in living embryos and adults, and by immunolocalization with an ELP-1-specific antibody in fixed tissues. In embryos, ELP-1 is expressed in the hypodermis. In larvae and adults, ELP-1 is expressed in the body wall, spermatheca and vulval muscles, intestine, and hypodermal seam cells. In muscle, ELP-1 is associated with adhesion complexes near the cell surface and is bound to a criss-crossing network of microtubules in the cytoplasm. ELP-1 is also expressed in a subset of mechanoreceptor neurons, including the ray neurons in the male tail, microtubule-rich touch receptor neurons, and the six ciliated IL1 neurons. This restricted localization in the nervous system implies that ELP-1 plays a role in mechanotransmission. Consistent with this idea, decreasing ELP-1 expression decreases sensitivity to gentle touch applied to the body wall. Conclusion These data imply that ELP-1 may play an important role during the transmission of forces and signals between the body surface and both muscle cells and touch receptor neurons. PMID:19014691

Hueston, Jennifer L; Herren, Gina Purinton; Cueva, Juan G; Buechner, Matthew; Lundquist, Erik A; Goodman, Miriam B; Suprenant, Kathy A

2008-01-01

304

Role of the microtubule-targeting drug vinflunine on cell-cell adhesions in bladder epithelial tumour cells  

PubMed Central

Background Vinflunine (VFL) is a microtubule-targeting drug that suppresses microtubule dynamics, showing anti-metastatic properties both in vitro and in living cancer cells. An increasing body of evidence underlines the influence of the microtubules dynamics on the cadherin-dependent cell-cell adhesions. E-cadherin is a marker of epithelial-to-mesenchymal transition (EMT) and a tumour suppressor; its reduced levels in carcinoma are associated with poor prognosis. In this report, we investigate the role of VFL on cell-cell adhesions in bladder epithelial tumour cells. Methods Human bladder epithelial tumour cell lines HT1376, 5637, SW780, T24 and UMUC3 were used to analyse cadherin-dependent cell-cell adhesions under VFL treatment. VFL effect on growth inhibition was measured by using a MTT colorimetric cell viability assay. Western blot, immunofluorescence and transmission electron microscopy analyses were performed to assess the roles of VFL effect on cell-cell adhesions, epithelial-to-mesenchymal markers and apoptosis. The role of the proteasome in controlling cell-cell adhesion was studied using the proteasome inhibitor MG132. Results We show that VFL induces cell death in bladder cancer cells and activates epithelial differentiation of the remaining living cells, leading to an increase of E-cadherin-dependent cell-cell adhesion and a reduction of mesenchymal markers, such as N-cadherin or vimentin. Moreover, while E-cadherin is increased, the levels of Hakai, an E3 ubiquitin-ligase for E-cadherin, were significantly reduced in presence of VFL. In 5637, this reduction on Hakai expression was blocked by MG132 proteasome inhibitor, indicating that the proteasome pathway could be one of the molecular mechanisms involved in its degradation. Conclusions Our findings underscore a critical function for VFL in cell-cell adhesions of epithelial bladder tumour cells, suggesting a novel molecular mechanism by which VFL may impact upon EMT and metastasis. PMID:25012153

2014-01-01

305

Cellular adhesion pathways and metastatic potential of human melanoma.  

PubMed

Cellular adhesion molecules of the cadherin, integrin, and immunoglobulin superfamilies are important to both growth and metastasis of many cancers, including malignant melanoma. Malignant melanoma is an excellent model for studying these molecules, due in part to a sequential series of five defineable stages. As the malignant phenotype of melanoma cells changes from the noninvasive radial growth phase to the vertical growth phase, which has high metastatic potential, so does the repertoire of the cellular adhesion molecules expressed on the cells surface. The cellular adhesion molecule MCAM/MUC18 confers metastatic potential and increased tumorigenicity to melanoma cells. MCAM/MUC18 mediates homotypic and heterotypic adhesion between melanoma cells and endothelial cells, respectively. Both types of interaction may promote metastasis at different stages in the metastasis cascade. We developed a fully humanized antibody to MCAM/MUC18 (ABX-MA1) that blocked melanoma metastasis in vivo. Furthermore, ABX-MA1 blocked the homotypic interaction between melanoma cells and endothelial cells as well as the promoter and collagenase activity of MMP-2. During melanoma progression the loss of E-cadherin expression disrupts normal homeostasis in the skin by freeing melanoma cells from structural and functional regulation by keratinocytes. The loss of functional E-cadherin is parallelled by a gain in N-cadherin function that mediates homotypic interaction between melanoma cells, facilitates gap-junctional formation with fibroblasts and endothelial cells and promotes melanoma cell migration and survival. In addition, loss of E-cadherin may affect the beta-catenin/wnt signaling pathways, resulting in deregulation of genes involved in growth and metastasis. The integrin family member alpha(v)beta(3) is widely expressed on melanoma cells in the vertical growth phase. When alpha(v)beta(3) is expressed in melanoma cells in the radial growth phase, this integrin is associated with increased tumor growth in vivo. alpha(v)beta(3) may also promote melanoma invasion, through an interaction with MMP-2, and transendothelial migration, via a heterotypic melanomaendothelial cell interaction. This review summarizes recent knowledge on how changes in these adhesion molecules contribute to the acquisition of the metastatic phenotype in human melanoma. PMID:12496470

McGary, Eric C; Lev, Dina Chelouche; Bar-Eli, Menashe

2002-01-01

306

Polyimide adhesives  

NASA Technical Reports Server (NTRS)

A process was developed for preparing aromatic polyamide acids for use as adhesives by reacting an aromatic dianhydride to an approximately equimolar amount of an aromatic diamine in a water or lower alkanol miscible ether solvent. The polyamide acids are converted to polyimides by heating to the temperature range of 200 - 300 C. The polyimides are thermally stable and insoluble in ethers and other organic solvents.

Progar, D. J.; Bell, V. L.; Stclair, T. L. (inventors)

1977-01-01

307

Alpha 1(E)-catenin is an actin-binding and -bundling protein mediating the attachment of F-actin to the membrane adhesion complex.  

PubMed Central

Calcium-dependent homotypic cell-cell adhesion, mediated by molecules such as E-cadherin, guides the establishment of classical epithelial cell polarity and contributes to the control of migration, growth, and differentiation. These actions involve additional proteins, including alpha- and beta-catenin (or plakoglobin) and p120, as well as linkage to the cortical actin cytoskeleton. The molecular basis for these interactions and their hierarchy of interaction remain controversial. We demonstrate a direct interaction between F-actin and alpha (E)-catenin, an activity not shared by either the cytoplasmic domain of E-cadherin or beta-catenin. Sedimentation assays and direct visualization by transmission electron microscopy reveal that alpha 1(E)-catenin binds and bundles F-actin in vitro with micromolar affinity at a catenin/G-actin monomer ratio of approximately 1:7 (mol/mol). Recombinant human beta-catenin can simultaneously bind to the alpha-catenin/actin complex but does not bind actin directly. Recombinant fragments encompassing the amino-terminal 228 residues of alpha 1(E)-catenin or the carboxyl-terminal 447 residues individually bind actin in cosedimentation assays with reduced affinity compared with the full-length protein, and neither fragment bundles actin. Except for similarities to vinculin, neither region contains sequences homologous to established actin-binding proteins. Collectively these data indicate that alpha 1 (E)-catenin is a novel actin-binding and -bundling protein and support a model in which alpha 1(E)-catenin is responsible for organizing and tethering actin filaments at the zones of E-cadherin-mediated cell-cell contact. Images Fig. 1 Fig. 2 Fig. 3 PMID:7568023

Rimm, D L; Koslov, E R; Kebriaei, P; Cianci, C D; Morrow, J S

1995-01-01

308

Semicircular canal morphogenesis in the zebrafish inner ear requires the function of gpr126 (lauscher), an adhesion class G protein-coupled receptor gene  

PubMed Central

Morphogenesis of the semicircular canal ducts in the vertebrate inner ear is a dramatic example of epithelial remodelling in the embryo, and failure of normal canal development results in vestibular dysfunction. In zebrafish and Xenopus, semicircular canal ducts develop when projections of epithelium, driven by extracellular matrix production, push into the otic vesicle and fuse to form pillars. We show that in the zebrafish, extracellular matrix gene expression is high during projection outgrowth and then rapidly downregulated after fusion. Enzymatic disruption of hyaluronan in the projections leads to their collapse and a failure to form pillars: as a result, the ears swell. We have cloned a zebrafish mutant, lauscher (lau), identified by its swollen ear phenotype. The primary defect in the ear is abnormal projection outgrowth and a failure of fusion to form the semicircular canal pillars. Otic expression of extracellular matrix components is highly disrupted: several genes fail to become downregulated and remain expressed at abnormally high levels into late larval stages. The lau mutations disrupt gpr126, an adhesion class G protein-coupled receptor gene. Expression of gpr126 is similar to that of sox10, an ear and neural crest marker, and is partially dependent on sox10 activity. Fusion of canal projections and downregulation of otic versican expression in a hypomorphic lau allele can be restored by cAMP agonists. We propose that Gpr126 acts through a cAMP-mediated pathway to control the outgrowth and adhesion of canal projections in the zebrafish ear via the regulation of extracellular matrix gene expression. PMID:24067352

Geng, Fan-Suo; Abbas, Leila; Baxendale, Sarah; Holdsworth, Celia J.; Swanson, A. George; Slanchev, Krasimir; Hammerschmidt, Matthias; Topczewski, Jacek; Whitfield, Tanya T.

2013-01-01

309

Exploring natural silk protein sericin for regenerative medicine: an injectable, photoluminescent, cell-adhesive 3D hydrogel  

PubMed Central

Sericin, a major component of silk, has a long history of being discarded as a waste during silk processing. The value of sericin for tissue engineering is underestimated and its potential application in regenerative medicine has just begun to be explored. Here we report the successful fabrication and characterization of a covalently-crosslinked 3D pure sericin hydrogel for delivery of cells and drugs. This hydrogel is injectable, permitting its implantation through minimally invasive approaches. Notably, this hydrogel is found to exhibit photoluminescence, enabling bioimaging and in vivo tracking. Moreover, this hydrogel system possesses excellent cell-adhesive capability, effectively promoting cell attachment, proliferation and long-term survival of various types of cells. Further, the sericin hydrogel releases bioactive reagents in a sustained manner. Additionally, this hydrogel demonstrates good elasticity, high porosity, and pH-dependent degradation dynamics, which are advantageous for this sericin hydrogel to serve as a delivery vehicle for cells and therapeutic drugs. With all these unique features, it is expected that this sericin hydrogel will have wide utility in the areas of tissue engineering and regenerative medicine. PMID:25412301

Wang, Zheng; Zhang, Yeshun; Zhang, Jinxiang; Huang, Lei; Liu, Jia; Li, Yongkui; Zhang, Guozheng; Kundu, Subhas C.; Wang, Lin

2014-01-01

310

Exploring natural silk protein sericin for regenerative medicine: an injectable, photoluminescent, cell-adhesive 3D hydrogel  

NASA Astrophysics Data System (ADS)

Sericin, a major component of silk, has a long history of being discarded as a waste during silk processing. The value of sericin for tissue engineering is underestimated and its potential application in regenerative medicine has just begun to be explored. Here we report the successful fabrication and characterization of a covalently-crosslinked 3D pure sericin hydrogel for delivery of cells and drugs. This hydrogel is injectable, permitting its implantation through minimally invasive approaches. Notably, this hydrogel is found to exhibit photoluminescence, enabling bioimaging and in vivo tracking. Moreover, this hydrogel system possesses excellent cell-adhesive capability, effectively promoting cell attachment, proliferation and long-term survival of various types of cells. Further, the sericin hydrogel releases bioactive reagents in a sustained manner. Additionally, this hydrogel demonstrates good elasticity, high porosity, and pH-dependent degradation dynamics, which are advantageous for this sericin hydrogel to serve as a delivery vehicle for cells and therapeutic drugs. With all these unique features, it is expected that this sericin hydrogel will have wide utility in the areas of tissue engineering and regenerative medicine.

Wang, Zheng; Zhang, Yeshun; Zhang, Jinxiang; Huang, Lei; Liu, Jia; Li, Yongkui; Zhang, Guozheng; Kundu, Subhas C.; Wang, Lin

2014-11-01

311

The conserved LIM domain-containing focal adhesion protein ZYX-1 regulates synapse maintenance in Caenorhabditis elegans.  

PubMed

We describe the identification of zyxin as a regulator of synapse maintenance in mechanosensory neurons in C. elegans. zyx-1 mutants lacked PLM mechanosensory synapses as adult animals. However, most PLM synapses initially formed during development but were subsequently lost as the animals developed. Vertebrate zyxin regulates cytoskeletal responses to mechanical stress in culture. Our work provides in vivo evidence in support of such a role for zyxin. In particular, zyx-1 mutant synaptogenesis phenotypes were suppressed by disrupting locomotion of the mutant animals, suggesting that zyx-1 protects mechanosensory synapses from locomotion-induced forces. In cultured cells, zyxin is recruited to focal adhesions and stress fibers via C-terminal LIM domains and modulates cytoskeletal organization via the N-terminal domain. The synapse-stabilizing activity was mediated by a short isoform of ZYX-1 containing only the LIM domains. Consistent with this notion, PLM synaptogenesis was independent of ?-actinin and ENA-VASP, both of which bind to the N-terminal domain of zyxin. Our results demonstrate that the LIM domain moiety of zyxin functions autonomously to mediate responses to mechanical stress and provide in vivo evidence for a role of zyxin in neuronal development. PMID:25252943

Luo, Shuo; Schaefer, Anneliese M; Dour, Scott; Nonet, Michael L

2014-10-01

312

Loss of Sertoli-germ cell adhesion determines the rapid germ cell elimination during the seasonal regression of the seminiferous epithelium of the large hairy armadillo Chaetophractus villosus.  

PubMed

The armadillo Chaetophractus villosus is a seasonal breeder whose seminiferous epithelium undergoes rapid regression with massive germ cell loss, leaving the tubules with only Sertoli cells and spermatogonia. Here, we addressed the question of whether this regression entails 1) the disassembly of cell junctions (immunolocalization of nectin-3, Cadm1, N-cadherin, and beta-catenin, and transmission electron microscopy [TEM]); 2) apoptosis (immunolocalization of cytochrome c and caspase 3; TUNEL assay); and 3) the involvement of Sertoli cells in germ cell phagocytosis (TEM). We showed a dramatic reduction in the extension of vimentin filaments associated with desmosomelike junctions at the interface between Sertoli and germ cells, and an increased diffusion of the immunosignals of nectin-3, Cadm1, N-cadherin, and beta-catenin. Together, these results suggest loss of Sertoli-germ cell adhesion, which in turn might determine postmeiotic cell sloughing at the beginning of epithelium regression. Then, loss of Sertoli-germ cell adhesion triggers cell death. Cytochrome c is released from mitochondria, but although postmeiotic cells were negative for late apoptotic markers, at advanced regression spermatocytes were positive for all apoptotic markers. Transmission electron microscopy analysis showed cytoplasmic engulfment of cell debris and lipid droplets within Sertoli cells, a sign of their phagocytic activity, which contributes to the elimination of the residual meiocytes still present in the latest regression phases. These findings are novel and add new players to the mechanisms of seminiferous epithelium regression occurring in seasonal breeders, and they introduce the armadillo as an interesting model for studying seasonal spermatogenesis. PMID:24451984

Luaces, Juan Pablo; Rossi, Luis Francisco; Sciurano, Roberta Beatriz; Rebuzzini, Paola; Merico, Valeria; Zuccotti, Maurizio; Merani, Maria Susana; Garagna, Silvia

2014-03-01

313

Exploiting the superior protein resistance of polymer brushes to control single cell adhesion and polarisation at the micron scale  

Microsoft Academic Search

The control of the cell microenvironment on model patterned substrates allows the systematic study of cell biology in well defined conditions, potentially using automated systems. The extreme protein resistance of poly(oligo(ethylene glycol methacrylate)) (POEGMA) brushes is exploited to achieve high fidelity patterning of single cells. These coatings can be patterned by soft lithography on large areas (a microscope slide) and

Julien E. Gautrot; Britta Trappmann; Fabian Oceguera-Yanez; John Connelly; Ximin He; Fiona M. Watt; Wilhelm T. S. Huck

2010-01-01

314

Binding of complement inhibitor C4b-binding protein to a highly virulent Streptococcus pyogenes M1 strain is mediated by protein H and enhances adhesion to and invasion of endothelial cells.  

PubMed

Streptococcus pyogenes AP1, a strain of the highly virulent M1 serotype, uses exclusively protein H to bind the complement inhibitor C4b-binding protein (C4BP). We found a strong correlation between the ability of AP1 and its isogenic mutants lacking protein H to inhibit opsonization with complement C3b and binding of C4BP. C4BP bound to immobilized protein H or AP1 bacteria retained its cofactor activity for degradation of (125)I-C4b. Furthermore, C4b deposited from serum onto AP1 bacterial surfaces was processed into C4c/C4d fragments, which did not occur on strains unable to bind C4BP. Recombinant C4BP mutants, which (i) lack certain CCP domains or (ii) have mutations in single aa as well as (iii) mutants with additional aa between different CCP domains were used to determine that the binding is mainly mediated by a patch of positively charged amino acid residues at the interface of domains CCP1 and CCP2. Using recombinant protein H fragments, we narrowed down the binding site to the N-terminal domain A. With a peptide microarray, we identified one single 18-amino acid-long peptide comprising residues 92-109, which specifically bound C4BP. Biacore was used to determine KD = 6 × 10(-7) M between protein H and a single subunit of C4BP. C4BP binding also correlated with elevated levels of adhesion and invasion to endothelial cells. Taken together, we identified the molecular basis of C4BP-protein H interaction and found that it is not only important for decreased opsonization but also for invasion of endothelial cells by S. pyogenes. PMID:24064215

Ermert, David; Weckel, Antonin; Agarwal, Vaibhav; Frick, Inga-Maria; Björck, Lars; Blom, Anna M

2013-11-01

315

A Lithium Chloride-Extracted, Broad-Spectrum-Adhesive 42-Kilodalton Protein of Staphylococcus epidermidis Is Ornithine Carbamoyltransferase  

Microsoft Academic Search

To identify novel putative staphylococcal adhesins, lithium chloride extraction (an established method for selective surface molecule solubilization) was employed. N-terminal sequencing and functional assays identi- fied a 42-kDa fibronectin-binding protein from Staphylococcus epidermidis as ornithine carbamoyltransferase (OCTase). However, OCTase was not recognizable extracellularly, and this fact together with the fact that LiCl induced DNA release and a decrease in viability

MUZAFFAR HUSSAIN; GEORG PETERS; GURSHARAN S. CHHATWAL; MATHIAS HERRMANN

1999-01-01

316

Presenilin-1 forms complexes with the cadherin/catenin cell-cell adhesion system and is recruited to intercellular and synaptic contacts.  

PubMed

In MDCK cells, presenilin-1 (PS1) accumulates at intercellular contacts where it colocalizes with components of the cadherin-based adherens junctions. PS1 fragments form complexes with E-cadherin, beta-catenin, and alpha-catenin, all components of adherens junctions. In confluent MDCK cells, PS1 forms complexes with cell surface E-cadherin; disruption of Ca(2+)-dependent cell-cell contacts reduces surface PS1 and the levels of PS1-E-cadherin complexes. PS1 overexpression in human kidney cells enhances cell-cell adhesion. Together, these data show that PS1 incorporates into the cadherin/catenin adhesion system and regulates cell-cell adhesion. PS1 concentrates at intercellular contacts in epithelial tissue; in brain, it forms complexes with both E- and N-cadherin and concentrates at synaptic adhesions. That PS1 is a constituent of the cadherin/catenin complex makes that complex a potential target for PS1 FAD mutations. PMID:10635315

Georgakopoulos, A; Marambaud, P; Efthimiopoulos, S; Shioi, J; Cui, W; Li, H C; Schütte, M; Gordon, R; Holstein, G R; Martinelli, G; Mehta, P; Friedrich, V L; Robakis, N K

1999-12-01

317

Differential regulation of extracellular matrix protein expression in carcinoma-associated fibroblasts by TGF-?1 regulates cancer cell spreading but not adhesion  

PubMed Central

Cancer progression is characterized by a complex reciprocity between neoplastic epithelium and adjacent stromal cells. In ductal carcinoma in situ (DCIS) of the breast, both reduced stromal decorin expression and myxoid stroma are correlated with increased recurrence risk. In this study, we aimed to investigate paracrine regulation of expression of decorin and related extracellular matrix (ECM) proteins in cancer-associated fibroblasts (CAFs). Transforming growth factor-?1 (TGF-?1) was identified as a competent ECM modulator, as it reduced decorin and strongly enhanced versican, biglycan and type I collagen expression. Similar but less pronounced effects were observed when fibroblasts were treated with basic fibroblast growth factor (bFGF). Despite this concerted ECM modulation, TGF-?1 and bFGF differentially regulated alpha-smooth muscle actin (?-SMA) expression, which is often proposed as a CAF-marker. Cancer cell-derived secretomes induced versican and biglycan expression in fibroblasts. Immunohistochemistry on twenty DCIS specimens showed a trend toward periductal versican overexpression in DCIS with myxoid stroma. Cancer cell adhesion was inhibited by decorin, but not by CAF-derived matrices. Cancer cells presented significantly enhanced spreading when seeded on matrices derived from TGF-?1-treated CAF. Altogether these data indicate that preinvasive cancerous lesions might modulate the composition of surrounding stroma through TGF-?1 release to obtain an invasion-permissive microenvironment. PMID:25593993

Van Bockstal, Mieke; Lambein, Kathleen; Van Gele, Mireille; De Vlieghere, Elly; Limame, Ridha; Braems, Geert; Van den Broecke, Rudy; Cocquyt, Veronique; Denys, Hannelore; Bracke, Marc; Libbrecht, Louis; De Wever, Olivier

2014-01-01

318

Mussel-Inspired Adhesives and Coatings  

PubMed Central

Mussels attach to solid surfaces in the sea. Their adhesion must be rapid, strong, and tough, or else they will be dislodged and dashed to pieces by the next incoming wave. Given the dearth of synthetic adhesives for wet polar surfaces, much effort has been directed to characterizing and mimicking essential features of the adhesive chemistry practiced by mussels. Studies of these organisms have uncovered important adaptive strategies that help to circumvent the high dielectric and solvation properties of water that typically frustrate adhesion. In a chemical vein, the adhesive proteins of mussels are heavily decorated with Dopa, a catecholic functionality. Various synthetic polymers have been functionalized with catechols to provide diverse adhesive, sealant, coating, and anchoring properties, particularly for critical biomedical applications. PMID:22058660

Lee, Bruce P.; Messersmith, P.B.; Israelachvili, J.N.; Waite, J.H.

2011-01-01

319

Tyrosine Phosphorylation of Growth Factor Receptor-bound Protein-7 by Focal Adhesion Kinase in the Regulation of Cell Migration, Proliferation, and Tumorigenesis*  

PubMed Central

We have previously reported that growth factor receptor-bound protein-7 (Grb7), an Src-homology 2 (SH2)-containing adaptor protein, enables interaction with focal adhesion kinase (FAK) to regulate cell migration in response to integrin activation. To further elucidate the signaling events mediated by FAK·Grb7 complexes in promoting cell migration and other cellular functions, we firstly examined the phos pho ryl a ted tyrosine site(s) of Grb7 by FAK using an in vivo mutagenesis. We found that FAK was capable of phos pho rylating at least 2 of 12 tyrosine residues within Grb7, Tyr-188 and Tyr-338. Moreover, mutations converting the identified Tyr to Phe inhibited integrin-dependent cell migration as well as impaired cell proliferation but not survival compared with the wild-type control. Interestingly, the above inhibitory effects caused by the tyrosine phos pho ryl a tion-deficient mutants are probably attributed to their down-regulation of phospho-Tyr-397 of FAK, thereby implying a mechanism by competing with wild-type Grb7 for binding to FAK. Consequently, these tyrosine phos pho ryl a tion-deficient mutants evidently altered the phospho-Tyr-118 of paxillin and phos pho ryl a tion of ERK1/2 but less on phospho-Ser-473 of AKT, implying their involvement in the FAK·Grb7-mediated cellular functions. Additionally, we also illustrated that the formation of FAK·Grb7 complexes and Grb7 phos pho ryl a tion by FAK in an integrin-dependent manner were essential for cell migration, proliferation and anchorage-independent growth in A431 epidermal carcinoma cells, indicating the importance of FAK·Grb7 complexes in tumorigenesis. Our data provide a better understanding on the signal transduction event for FAK·Grb7-mediated cellular functions as well as to shed light on a potential therapeutic in cancers. PMID:19473962

Chu, Pei-Yu; Huang, Ling-Ya; Hsu, Chun-Hua; Liang, Chun-Chi; Guan, Jun-Lin; Hung, Ting-Hsuan; Shen, Tang-Long

2009-01-01

320

Exploiting the superior protein resistance of polymer brushes to control single cell adhesion and polarisation at the micron scale.  

PubMed

The control of the cell microenvironment on model patterned substrates allows the systematic study of cell biology in well defined conditions, potentially using automated systems. The extreme protein resistance of poly(oligo(ethylene glycol methacrylate)) (POEGMA) brushes is exploited to achieve high fidelity patterning of single cells. These coatings can be patterned by soft lithography on large areas (a microscope slide) and scale (substrates were typically prepared in batches of 200). The present protocol relies on the adsorption of extra-cellular matrix (ECM) proteins on unprotected areas using simple incubation and washing steps. The stability of POEGMA brushes, as examined via ellipsometry and SPR, is found to be excellent, both during storage and cell culture. The impact of substrate treatment, brush thickness and incubation protocol on ECM deposition, both for ultra-thin gold and glass substrates, is investigated via fluorescence microscopy and AFM. Optimised conditions result in high quality ECM patterns at the micron scale, even on glass substrates, that are suitable for controlling cell spreading and polarisation. These patterns are compatible with state-of-the-art technologies (fluorescence microscopy, FRET) used for live cell imaging. This technology, combined with single cell analysis methods, provides a platform for exploring the mechanisms that regulate cell behaviour. PMID:20347135

Gautrot, Julien E; Trappmann, Britta; Oceguera-Yanez, Fabian; Connelly, John; He, Ximin; Watt, Fiona M; Huck, Wilhelm T S

2010-06-01

321

Exploiting the superior protein resistance of polymer brushes to control single cell adhesion and polarisation at the micron scale  

PubMed Central

The control of the cell microenvironment on model patterned substrates allows the systematic study of cell biology in well defined conditions, potentially using automated systems. The extreme protein resistance of poly(oligo(ethylene glycol methacrylate)) (POEGMA) brushes is exploited to achieve high fidelity patterning of single cells. These coatings can be patterned by soft lithography on large areas (a microscope slide) and scale (substrates were typically prepared in batches of 200). The present protocol relies on the adsorption of extra-cellular matrix (ECM) proteins on unprotected areas using simple incubation and washing steps. The stability of POEGMA brushes, as examined via ellipsometry and SPR, is found to be excellent, both during storage and cell culture. The impact of substrate treatment, brush thickness and incubation protocol on ECM deposition, both for ultra-thin gold and glass substrates, is investigated via fluorescence microscopy and AFM. Optimised conditions result in high quality ECM patterns at the micron scale, even on glass substrates, that are suitable for controlling cell spreading and polarisation. These patterns are compatible with state-of-the-art technologies (fluorescence microscopy, FRET) used for live cell imaging. This technology, combined with single cell analysis methods, provides a platform for exploring the mechanisms that regulate cell behaviour. PMID:20347135

Gautrot, Julien E.; Trappmann, Britta; Oceguera-Yanez, Fabian; Connelly, John; He, Ximin; Watt, Fiona M.; Huck, Wilhelm T.S.

2010-01-01

322

Estrogen and pure antiestrogen fulvestrant (ICI 182 780) augment cell-matrigel adhesion of MCF-7 breast cancer cells through a novel G protein coupled estrogen receptor (GPR30)-to-calpain signaling axis.  

PubMed

Fulvestrant (ICI 182 780, ICI) has been used in treating patients with hormone-sensitive breast cancer, yet initial or acquired resistance to endocrine therapies frequently arises and, in particular, cancer recurs as metastasis. We demonstrate here that both 17-beta-estradiol (E2) and ICI enhance cell adhesion to matrigel in MCF-7 breast cancer cells, with increased autolysis of calpain 1 (large subunit) and proteolysis of focal adhesion kinase (FAK), indicating calpain activation. Additionally, either E2 or ICI induced down-regulation of estrogen receptor ? without affecting G protein coupled estrogen receptor 30 (GPR30) expression. Interestingly, GPR30 agonist G1 triggered calpain 1 autolysis but not calpain 2, whereas ER agonist diethylstilbestrol caused no apparent calpain autolysis. Furthermore, the actions of E2 and ICI on calpain and cell adhesion were tremendously suppressed by G15, or knockdown of GPR30. E2 and ICI also induced phosphorylation of extracellular regulated protein kinases 1 and 2 (ERK1/2), and suppression of ERK1/2 phosphorylation by U0126 profoundly impeded calpain activation triggered by estrogenic and antiestrogenic stimulations indicating implication of ERK1/2 in the GPR30-mediated action. Lastly, the E2- or ICI-induced cell adhesion was dramatically impaired by calpain-specific inhibitors, ALLN or calpeptin, suggesting requirement of calpain in the GPR30-associated action. These data show that enhanced cell adhesion by E2 and ICI occurs via a novel GPR30-ERK1/2-calpain pathway. Our results indicate that targeting the GPR30 signaling may be a potential strategy to reduce metastasis and improve the efficacy of antiestrogens in treatment of advanced breast cancer. PMID:24440569

Chen, Yan; Li, Zheng; He, Yan; Shang, Dandan; Pan, Jigang; Wang, Hongmei; Chen, Huamei; Zhu, Zhuxia; Wan, Lei; Wang, Xudong

2014-03-01

323

Piezoelectric inkjet printing of medical adhesives and sealants  

NASA Astrophysics Data System (ADS)

Piezoelectric inkjet printing is a noncontact process that enables microscale processing of biological materials. In this research summary, the use of piezoelectric inkjet printing for patterning medical adhesives and sealants, including a two-component polyethylene glycol hydrogel-based medical sealant, an N-butyl cyanoacrylate tissue adhesive, and a mussel adhesive protein biological adhesive, is described The effect of Fe(III) on mussel adhesive protein structure was evaluated by means of atomic force microscopy. The ability to process microscale patterns of medical sealants and adhesives will provide an improvement in tissue joining, including enhanced tissue integrity, reduced bond lines, and decreased adhesive toxicity. Piezoelectric inkjet deposition of medical adhesives and sealants may be used in wound closure, fracture fixation, and microscale vascular surgery.

Boehm, Ryan D.; Gittard, Shaun D.; Byrne, Jacqueline M. H.; Doraiswamy, Anand; Wilker, Jonathan J.; Dunaway, Timothy M.; Crombez, Rene; Shen, Weidian; Lee, Yuan-Shin; Narayan, Roger J.

2010-07-01

324

Biological adhesion of the flatworm Macrostomum lignano relies on a duo-gland system and is mediated by a cell type-specific intermediate filament protein  

PubMed Central

Background Free-living flatworms, in both marine and freshwater environments, are able to adhere to and release from a substrate several times within a second. This reversible adhesion relies on adhesive organs comprised of three cell types: an adhesive gland cell, a releasing gland cell, and an anchor cell, which is a modified epidermal cell responsible for structural support. However, nothing is currently known about the molecules that are involved in this adhesion process. Results In this study we present the detailed morphology of the adhesive organs of the free-living marine flatworm Macrostomum lignano. About 130 adhesive organs are located in a horse-shoe-shaped arc along the ventral side of the tail plate. Each organ consists of exactly three cells, an adhesive gland cell, a releasing gland cell, and an anchor cell. The necks of the two gland cells penetrate the anchor cell through a common pore. Modified microvilli of the anchor cell form a collar surrounding the necks of the adhesive- and releasing glands, jointly forming the papilla, the outer visible part of the adhesive organs. Next, we identified an intermediate filament (IF) gene, macif1, which is expressed in the anchor cells. RNA interference mediated knock-down resulted in the first experimentally induced non-adhesion phenotype in any marine animal. Specifically, the absence of intermediate filaments in the anchor cells led to papillae with open tips, a reduction of the cytoskeleton network, a decline in hemidesmosomal connections, and to shortened microvilli containing less actin. Conclusion Our findings reveal an elaborate biological adhesion system in a free-living flatworm, which permits impressively rapid temporary adhesion-release performance in the marine environment. We demonstrate that the structural integrity of the supportive cell, the anchor cell, is essential for this adhesion process: the knock-down of the anchor cell-specific intermediate filament gene resulted in the inability of the animals to adhere. The RNAi mediated changes of the anchor cell morphology are comparable to situations observed in human gut epithelia. Therefore, our current findings and future investigations using this powerful flatworm model system might contribute to a better understanding of the function of intermediate filaments and their associated human diseases. PMID:24520881

2014-01-01

325

Activation of Myeloid Cell-Specific Adhesion Class G Protein-Coupled Receptor EMR2 via Ligation-Induced Translocation and Interaction of Receptor Subunits in Lipid Raft Microdomains  

PubMed Central

The adhesion class G protein-coupled receptors (adhesion-GPCRs) play important roles in diverse biological processes ranging from immunoregulation to tissue polarity, angiogenesis, and brain development. These receptors are uniquely modified by self-catalytic cleavage at a highly conserved GPCR proteolysis site (GPS) dissecting the receptor into an extracellular subunit (?) and a seven-pass transmembrane subunit (?) with cellular adhesion and signaling functions, respectively. Using the myeloid cell-restricted EMR2 receptor as a paradigm, we exam the mechanistic relevance of the subunit interaction and demonstrate a critical role for GPS autoproteolysis in mediating receptor signaling and cell activation. Interestingly, two distinct receptor complexes are identified as a result of GPS proteolysis: one consisting of a noncovalent ?-? heterodimer and the other comprising two completely independent receptor subunits which distribute differentially in membrane raft microdomains. Finally, we show that receptor ligation induces subunit translocation and colocalization within lipid rafts, leading to receptor signaling and inflammatory cytokine production by macrophages. Our present data resolve earlier conflicting results and provide a new mechanism of receptor signaling, as well as providing a paradigm for signal transduction within the adhesion-GPCR family. PMID:22310662

Huang, Yi-Shu; Chiang, Nien-Yi; Hu, Ching-Hsun; Hsiao, Cheng-Chih; Cheng, Kai-Fong; Tsai, Wen-Pin; Yona, Simon; Stacey, Martin; Gordon, Siamon

2012-01-01

326

Snail Regulates Cell-Matrix Adhesion by Regulation of the Expression of Integrins and Basement Membrane Proteins*  

PubMed Central

Snail, a transcriptional repressor of E-cadherin expression, plays a role in the process of epithelial-mesenchymal transition. However, the molecular basis of the role of snail in epithelial-mesenchymal transition has not been fully clarified. Here we show that the expression of snail in epithelial Madin-Darby canine kidney (MDCK) and A431 cells enhances both cell detachment and attachment. Snail did not confer resistance to anoikis induced by loss of contact but instead enhanced cell attachment to extracellular matrices such as fibronectin. This attachment was inhibited by Arg-Gly-Asp (RGD) peptides. Up-regulation of the promoter activity of integrin ?V was observed in snail-expressing MDCK (MDCK/snail) cells. Snail also enhanced MDCK cell migration toward osteopontin that is a ligand for integrin ?V?3. We confirmed the reduction of basement membrane proteins such as laminin (LN) ?3, ?3, and ?2 (laminin-5/LN-5) and of receptors for LN-5 such as integrins ?3, ?6, or ?4 in MDCK/snail or in snail-expressing A431 (A431/snail) cells. Nevertheless, suppression of LN-?3 chain by transient transfection of small interference RNAs resulted in no enhancement of cell detachment. We also found an induction of matrix metalloproteinase-3 in MDCK/snail and A431/snail cells. However, the inhibition of matrix metalloproteinase-3 showed no significant effect on the detachment of MDCK/snail cells. These results suggest that snail enhances cell detachment by multiple mechanism and leads to cell migration and reattachment at a second site, at least in part, by changing the expression of integrins in the cells. PMID:18593711

Haraguchi, Misako; Okubo, Tadashi; Miyashita, Yayoi; Miyamoto, Yasunori; Hayashi, Masao; Crotti, Tania N.; McHugh, Kevin P.; Ozawa, Masayuki

2008-01-01

327

In vivo endothelization of tubular vascular grafts through in situ recruitment of endothelial and endothelial progenitor cells by RGD-fused mussel adhesive proteins.  

PubMed

The use of tissue mimics in vivo, including patterned vascular networks, is expected to facilitate the regeneration of functional tissues and organs with large volumes. Maintaining patency of channels in contact with blood is an important issue in the development of a functional vascular network. Endothelium is the only known completely non-thrombogenic material; however, results from treatments to induce endothelialization are inconclusive. The present study was designed to evaluate the clinical applicability of in situ recruitment of endothelial cells/endothelial progenitor cells (EC/EPC) and pre-endothelization using a recombinant mussel adhesive protein fused with arginine-glycine-aspartic acid peptide (MAP-RGD) coating in a model of vascular graft implantation. Microporous polycaprolactone (PCL) scaffolds were fabricated with salt leaching methods and their surfaces were modified with collagen and MAP-RGD. We then evaluated their anti-thrombogenicity with an in vitro hemocompatibility assessment and a 4-week implantation in the rabbit carotid artery. We observed that MAP-RGD coating reduced the possibility of early in vivo graft failure and enhanced re-endothelization by in situ recruitment of EC/EPC (patency rate: 2/3), while endothelization prior to implantation aggravated the formation of thrombosis and/or IH (patency rate: 0/3). The results demonstrated that in situ recruitment of EC/EPC by MAP-RGD could be a promising strategy for vascular applications. In addition, it rules out several issues associated with pre-endothelization, such as cell source, purity, functional modulation and contamination. Further evaluation of long term performance and angiogenesis from the luminal surface may lead to the clinical use of MAP-RGD for tubular vascular grafts and regeneration of large-volume tissues with functional vascular networks. PMID:25599716

Kang, Tae-Yun; Lee, Jung Ho; Kim, Bum Jin; Kang, Jo-A; Hong, Jung Min; Kim, Byoung Soo; Cha, Hyung Joon; Rhie, Jong-Won; Cho, Dong-Woo

2015-01-01

328

Effect of Hyperketonemia (Acetoacetate) on Nuclear Factor-?B and p38 Mitogen-Activated Protein Kinase Activation Mediated Intercellular Adhesion Molecule 1 Upregulation in Endothelial Cells.  

PubMed

Abstract Background: Hyperketonemia is a pathological condition observed in patients with type 1 diabetes and ketosis-prone diabetes (KPD), which results in increased blood levels of acetoacetate (AA) and ?-hydroxybutyrate (BHB). Frequent episodes of hyperketonemia are associated with a higher incidence of vascular disease. We examined the hypothesis that hyperketonemia activates the nuclear factor-?B (NF-?B) and mitogen-activated protein kinase (MAPK) signaling pathways that regulate intercellular adhesion molecule 1 (ICAM-1) expression in endothelial cells. Methods: Human umbilical vein endothelial cells (HUVECs) were cultured with AA (0-8?mM) or BHB (0-10?mM) for 0-24?hr. Western blotting was used to determine NF-?B activation in whole-cell lysates. ICAM-1 expression was measured using flow cytometry. Results: Results show a 2.4-fold increase in NF-?B activation in cells treated with 8?mM AA compared to the control. BHB had little or no effect on NF-?B activation. Pretreatment with a reactive oxygen species (ROS) inhibitor [N-acetyl-l-cysteine (NAC)] reduced NF-?B to near-control levels. The expression of AA-induced ICAM-1 was significantly reduced when cells were pretreated with either NAC or p38 MAPK inhibitor. Conclusions: These results suggest that NF-?B and p38 MAPK mediate upregulation of ICAM-1 expression in endothelial cells exposed to elevated levels of AA, which may contribute to the development of vascular disease in diabetes. PMID:25489974

Rains, Justin L; Jain, Sushil K

2014-12-01

329

Thermal Characterization of Adhesive  

NASA Technical Reports Server (NTRS)

The current Space Shuttle Reusable Solid Rocket Motor (RSRM) nozzle adhesive bond system is being replaced due to obsolescence. Down-selection and performance testing of the structural adhesives resulted in the selection of two candidate replacement adhesives, Resin Technology Group's Tiga 321 and 3M's EC2615XLW. This paper describes rocket motor testing of these two adhesives. Four forty-pound charge motors were fabricated in configurations that would allow side by side comparison testing of the candidate replacement adhesives and the current RSRM adhesives. The motors provided an environment where the thermal performance of adhesives in flame surface bondlines was compared. Results of the FPC testing show that: 1) The phenolic char depths on radial bond lines is approximately the same and vary depending on the position in the blast tube regardless of which adhesive was used; 2) The adhesive char depth of the candidate replacement adhesives is less than the char depth of the current adhesives; 3) The heat-affected depth of the candidate replacement adhesives is less than the heat-affected depth of the current adhesives; and 4) The ablation rates for both replacement adhesives are slower than that of the current adhesives.

Spomer, Ken A.

1999-01-01

330

E-cadherin's role in development, tissue homeostasis and disease: Insights from mouse models: Tissue-specific inactivation of the adhesion protein E-cadherin in mice reveals its functions in health and disease.  

PubMed

Recent studies uncovered critical roles of the adhesion protein E-cadherin in health and disease. Global inactivation of Cdh1, the gene encoding E-cadherin in mice, results in early embryonic lethality due to an inability to form the trophectodermal epithelium. To unravel E-cadherin's functions beyond development, numerous mouse lines with tissue-specific disruption of Cdh1 have been generated. The consequences of E-cadherin loss showed great variability depending on the tissue in question, ranging from nearly undetectable changes to a complete loss of tissue structure and function. This review focuses on these studies and discusses how they provided important insights into E-cadherin's role in cell adhesion, proliferation and differentiation, and its consequences for biological processes as epithelial-to-mesenchymal transition, vascularization, and carcinogenesis. Lastly, we present some perspectives and possible approaches for future research. PMID:25449798

Schneider, Marlon R; Kolligs, Frank T

2015-03-01

331

Expression of adhesion molecules on human granulocytes after stimulation with Helicobacter pylori membrane proteins: comparison with membrane proteins from other bacteria.  

PubMed Central

Type B gastritis in its active form is characterized by a dense infiltration of the lamina propria with granulocytes. Since the bacterium Helicobacter pylori does not invade the epithelial barrier, a signaling pathway chemoattractive for granulocytes must exist across this mucosal boarder. One possible mechanism tested was whether granulocytes are directly activated by water-soluble membrane proteins (WSP) from H. pylori. These findings were compared with the effects of WSP from other bacteria (Helicobacter felis, Campylobacter jejuni, Escherichia coli, and Staphylococcus aureus). A unique activation pattern by H. pylori WSP was found. Like all other WSP tested, they induced an upregulation of CD11b but had no influence on CD11c and, most strikingly, CD62L expression. In contrast, E. coli WSP, e.g., not only induce a strong CD11b and CD11c expression but also lead to a loss in surface CD62L. The lack of CD62L shedding conserves rolling of granulocytes along the endothelium, creating a favorable precondition for granulocytes to stick more readily to activated endothelium after H. pylori stimulation via CD11b-CD54 receptor-counterreceptor interaction. This may explain why H. pylori infection is a very strong stimulus for granulocyte infiltration. The active fraction for the induction of CD11b on granulocytes is a heat- and protease-sensitive protein with a molecular mass between 30 and 100 kDa. One activation step involved may be the binding of WSP to CD15 determinants on granulocytes with subsequent induction of CD11b. PMID:7540595

Enders, G; Brooks, W; von Jan, N; Lehn, N; Bayerdörffer, E; Hatz, R

1995-01-01

332

Bistability of Cell Adhesion in Shear Flow  

PubMed Central

Cell adhesion plays a central role in multicellular organisms helping to maintain their integrity and homeostasis. This complex process involves many different types of adhesion proteins, and synergetic behavior of these proteins during cell adhesion is frequently observed in experiments. A well-known example is the cooperation of rolling and stationary adhesion proteins during the leukocytes extravasation. Despite the fact that such cooperation is vital for proper functioning of the immune system, its origin is not fully understood. In this study we constructed a simple analytic model of the interaction between a leukocyte and the blood vessel wall in shear flow. The model predicts existence of cell adhesion bistability, which results from a tug-of-war between two kinetic processes taking place in the cell-wall contact area—bond formation and rupture. Based on the model results, we suggest an interpretation of several cytoadhesion experiments and propose a simple explanation of the existing synergy between rolling and stationary adhesion proteins, which is vital for effective cell adherence to the blood vessel walls in living organisms. PMID:21889439

Efremov, Artem; Cao, Jianshu

2011-01-01

333

Cell adhesion receptors - signaling capacity and exploitation by bacterial pathogens  

Microsoft Academic Search

Cell adhesion receptors play an essential role in multicellular organisms by mediating the direct association of cells with each other and with proteins of the extracellular matrix. Members of different protein families such as integrins, cadherins, immunoglobulin superfamily cell adhesion molecules (IgCAMs), selectins, and syndecans not only support the structural integrity of cells and tissues, but also contribute to the

Christof R. Hauck

2002-01-01

334

Antibodies to the Plasmodium falciparum antigens circumsporozoite protein, thrombospondin-related adhesive protein, and liver-stage antigen 1 vary by ages of subjects and by season in a highland area of Kenya.  

PubMed

Immunoglobulin G (IgG) antibodies to three vaccine candidate preerythrocytic Plasmodium falciparum antigens were evaluated in children and adults in an epidemic-prone highland area of Kenya during rainy (high-transmission) and dry (low-transmission) seasons. The frequencies and median levels of IgG antibodies to circumsporozoite protein (CSP) and thrombospondin-related adhesive protein (TRAP) were compared to the frequencies and median levels of IgG antibodies to liver-stage antigen 1 (LSA-1) reported previously. The frequencies and median levels of IgG antibodies to CSP and TRAP were similar in children and adults in the rainy season, but they were lower in children than in adults in the dry season. The frequencies and median levels of antibodies to LSA-1 were lower in children than in adults in both the rainy and dry seasons. Antibodies to CSP and LSA-1 were primarily members of the IgG1 and IgG3 subclasses, while antibodies to TRAP were primarily members of the IgG3 and IgG4 subclasses. In a treatment-reinfection study following dry season testing, antibodies to TRAP were associated with a trend toward protection from infection in children (P = 0.051) but not in adults. Antibodies to LSA-1 and CSP did not correlate with protection in children or adults. In this highland area of Kenya with unstable transmission, IgG antibodies to preerythrocytic P. falciparum antigens vary in subjects by age and season, and the protective effects of these antibodies against infection may be different in adults and children. PMID:12874308

John, Chandy C; Zickafoose, Joseph S; Sumba, P Odada; King, Christopher L; Kazura, James W

2003-08-01

335

Internal Tissue Adhesive Approved  

MedlinePLUS

... on this page, please enable JavaScript. Internal Tissue Adhesive Approved TissuGlu connects tissue flaps stemming from surgery ... and Drug Administration has approved the first tissue adhesive for internal use. Known as TissuGlu, surgeons can ...

336

Single-molecule mechanics of mussel adhesion  

NASA Astrophysics Data System (ADS)

The glue proteins secreted by marine mussels bind strongly to virtually all inorganic and organic surfaces in aqueous environments in which most adhesives function poorly. Studies of these functionally unique proteins have revealed the presence of the unusual amino acid 3,4-dihydroxy-L-phenylalanine (dopa), which is formed by posttranslational modification of tyrosine. However, the detailed binding mechanisms of dopa remain unknown, and the chemical basis for mussels' ability to adhere to both inorganic and organic surfaces has never been fully explained. Herein, we report a single-molecule study of the substrate and oxidation-dependent adhesive properties of dopa. Atomic force microscopy (AFM) measurements of a single dopa residue contacting a wet metal oxide surface reveal a surprisingly high strength yet fully reversible, noncovalent interaction. The magnitude of the bond dissociation energy as well as the inability to observe this interaction with tyrosine suggests that dopa is critical to adhesion and that the binding mechanism is not hydrogen bond formation. Oxidation of dopa, as occurs during curing of the secreted mussel glue, dramatically reduces the strength of the interaction to metal oxide but results in high strength irreversible covalent bond formation to an organic surface. A new picture of the interfacial adhesive role of dopa emerges from these studies, in which dopa exploits a remarkable combination of high strength and chemical multifunctionality to accomplish adhesion to substrates of widely varying composition from organic to metallic. 3,4-dihydroxylphenylalanine | atomic force microscopy | mussel adhesive protein

Lee, Haeshin; Scherer, Norbert F.; Messersmith, Phillip B.

2006-08-01

337

Integrins and cadherins join forces to form adhesive networks  

PubMed Central

Cell–cell and cell–extracellular-matrix (cell–ECM) adhesions have much in common, including shared cytoskeletal linkages, signaling molecules and adaptor proteins that serve to regulate multiple cellular functions. The term ‘adhesive crosstalk’ is widely used to indicate the presumed functional communication between distinct adhesive specializations in the cell. However, this distinction is largely a simplification on the basis of the non-overlapping subcellular distribution of molecules that are involved in adhesion and adhesion-dependent signaling at points of cell–cell and cell–substrate contact. The purpose of this Commentary is to highlight data that demonstrate the coordination and interdependence of cadherin and integrin adhesions. We describe the convergence of adhesive inputs on cell signaling pathways and cytoskeletal assemblies involved in regulating cell polarity, migration, proliferation and survival, differentiation and morphogenesis. Cell–cell and cell–ECM adhesions represent highly integrated networks of protein interactions that are crucial for tissue homeostasis and the responses of individual cells to their adhesive environments. We argue that the machinery of adhesion in multicellular tissues comprises an interdependent network of cell–cell and cell–ECM interactions and signaling responses, and not merely crosstalk between spatially and functionally distinct adhesive specializations within cells. PMID:21444749

Weber, Gregory F.; Bjerke, Maureen A.; DeSimone, Douglas W.

2011-01-01

338

C-Reactive Protein and Soluble Vascular Cell Adhesion Molecule1 Are Associated With Elevated Urinary Albumin Excretion but Do Not Explain Its Link With Cardiovascular Risk  

Microsoft Academic Search

An elevated urinary albumin excretion rate (UAER) is associated with an increased risk of cardiovascular mortality, but the pathophysiological mechanism underlying this association is poorly understood. To investigate the role of endothelial dysfunction, leukocyte adhesion, and low-grade inflammation (1) in the development of elevated UAER (study I) and (2) in linking elevated UAER with risk of cardiovascular mortality (study II),

Agnes Jager; Victor W. M. van Hinsbergh; Piet J. Kostense; Jef J. Emeis; Giel Nijpels; Jacqueline M. Dekker; Robert J. Heine; Lex M. Bouter; Coen D. A. Stehouwer

339

Desmoglein 2 compensates for desmoglein 3 but does not control cell adhesion via regulation of p38 mitogen-activated protein kinase in keratinocytes.  

PubMed

Desmosomal cadherins are transmembrane adhesion molecules that provide cell adhesion by interacting in the intercellular space of adjacent cells. In keratinocytes, several desmoglein (Dsg1-4) and desmocollin (Dsc1-3) isoforms are coexpressed. We have shown previously that Dsg2 is less important for keratinocyte cohesion compared with Dsg3 and that the latter forms a complex with p38 MAPK. In this study, we compared the involvement of Dsg2 and Dsg3 in the p38 MAPK-dependent regulation of keratinocyte cohesion. We show that loss of cell adhesion and keratin filament retraction induced by Dsg3 depletion is ameliorated by specific p38 MAPK inhibition. Furthermore, in contrast to depletion of Dsg2, siRNA-mediated silencing of Dsg3 induced p38 MAPK activation, which is in line with immunoprecipitation experiments demonstrating the interaction of activated p38 MAPK with Dsg3 but not with Dsg2. Cell fractionation into a cytoskeleton-unbound and a cytoskeleton-anchored desmosome-containing pool revealed that Dsg3, in contrast to Dsg2, is present in relevant amounts in the unbound pool in which activated p38 MAPK is predominantly detectable. Moreover, because loss of cell adhesion by Dsg3 depletion was partially rescued by p38 MAPK inhibition, we conclude that, besides its function as an adhesion molecule, Dsg3 is strengthening cell cohesion via modulation of p38 MAPK-dependent keratin filament reorganization. Nevertheless, because subsequent targeting of Dsg3 in Dsg2-depleted cells led to drastically enhanced keratinocyte dissociation and Dsg2 was enhanced at the membrane in Dsg3 knockout cells, we conclude that Dsg2 compensates for Dsg3 loss of function. PMID:24782306

Hartlieb, Eva; Rötzer, Vera; Radeva, Mariya; Spindler, Volker; Waschke, Jens

2014-06-13

340

Preparation of poly(cyclooctene)-g-poly(ethylene glycol) (PCOE-g-PEG) graft copolymers with tunable PEG side chains via ROMP and its protein adsorption and platelet adhesion properties.  

PubMed

In our previous work [H. Shi, D. Shi et al., Polymer Chemistry 2(2011)679-684], polycyclooctene-g-PEG (PCOE-g-PEG) copolymers were synthesized via ring opening metathesis polymerization (ROMP) from PEG functionalized cyclic olefin macromonomers and cyclooctene. The grafting degree and the grafting site were easily controlled through the "grafting through" approach. The PCOE-g-PEG film surface was imparted excellent anti-protein adsorption properties. In that work, the molecular weight of PEG side chain was fixed at 750g/mol and the neat PEG content in the copolymer was lower than 50wt.%. In this work, both the effects of PEG side chain lengths (350 to 1000g/mol) at a fixed PEG content (50wt.%) and the neat PEG content (30wt.% to 70wt.%) at a fixed PEG molecular weight (750g/mol) on the anti-protein adsorption and anti-platelet adhesion properties are studied. It is shown that the copolymer with 60wt.% PEG side chains of 750g/mol, where both PEG and PCOE form continuous morphology, is optimal to reduce the adsorption of both the bovine serum albumin (BSA) and platelet. When the PEG content reaches 70wt.%, phase inversion happens. PEG is the continuous phase but PCOE becomes the dispersed phase. The surface roughness of the casting PCOE-g-PEG film increases. In this case, both BSA adsorption and platelet adhesion will slightly increase comparing to the sample with 60wt.% PEG. PMID:25491862

Yang, Ying; Shi, Dean; Wang, Xueli; Shi, Hengchong; Jiang, Tao; Yang, Yingkui; Luan, Shifang; Yin, Jinghua; Li, Robert K Y

2014-12-01

341

Mechanism and dynamics of cadherin adhesion.  

PubMed

Cadherins are essential cell adhesion molecules involved in tissue morphogenesis and the maintenance of tissue architecture in adults. The adhesion and selectivity functions of cadherins are located in their extracellular regions. Biophysical studies show that the adhesive activity is not confined to a single interface. Instead, multiple cadherin domains contribute to binding. By contrast, the specificity-determining site maps to the N-terminal domains, which adhere by the reciprocal binding of Trp2 residues from opposing proteins. Structural cooperativity can transmit the effects of subtle structural changes or ligand binding over large distances in the protein. Increasingly, studies show that differential cadherin-mediated adhesion, rather than exclusive homophilic binding between identical cadherins, direct cell segregation and the organization of tissue interfaces during morphogenesis. Force measurements quantified both kinetic and strength differences between different classical cadherins that may underlie cell sorting behavior. Despite the complex adhesion mechanisms and differences in binding properties, cadherin-mediated cell adhesion is also regulated by many other biochemical processes. Elucidating the mechanisms by which cadherins organize cell junctions and tissue architecture requires not only quantitative, mechanistic investigations of cadherin function but also investigations of the biochemical and cellular processes that can modulate those functions. PMID:16834557

Leckband, Deborah; Prakasam, Anil

2006-01-01

342

Microtubule-Dependent Modulation of Adhesion Complex Composition  

PubMed Central

The microtubule network regulates the turnover of integrin-containing adhesion complexes to stimulate cell migration. Disruption of the microtubule network results in an enlargement of adhesion complex size due to increased RhoA-stimulated actomyosin contractility, and inhibition of adhesion complex turnover; however, the microtubule-dependent changes in adhesion complex composition have not been studied in a global, unbiased manner. Here we used label-free quantitative mass spectrometry-based proteomics to determine adhesion complex changes that occur upon microtubule disruption with nocodazole. Nocodazole-treated cells displayed an increased abundance of the majority of known adhesion complex components, but no change in the levels of the fibronectin-binding ?5?1 integrin. Immunofluorescence analyses confirmed these findings, but revealed a change in localisation of adhesion complex components. Specifically, in untreated cells, ?5-integrin co-localised with vinculin at peripherally located focal adhesions and with tensin at centrally located fibrillar adhesions. In nocodazole-treated cells, however, ?5-integrin was found in both peripherally located and centrally located adhesion complexes that contained both vinculin and tensin, suggesting a switch in the maturation state of adhesion complexes to favour focal adhesions. Moreover, the switch to focal adhesions was confirmed to be force-dependent as inhibition of cell contractility with the Rho-associated protein kinase inhibitor, Y-27632, prevented the nocodazole-induced conversion. These results highlight a complex interplay between the microtubule cytoskeleton, adhesion complex maturation state and intracellular contractile force, and provide a resource for future adhesion signaling studies. The proteomics data have been deposited in the ProteomeXchange with identifier PXD001183. PMID:25526367

Ng, Daniel H. J.; Humphries, Jonathan D.; Byron, Adam; Millon-Frémillon, Angélique; Humphries, Martin J.

2014-01-01

343

Activation of focal adhesion kinase enhances the adhesion and invasion of pancreatic cancer cells via extracellular signal-regulated kinase-1\\/2 signaling pathway activation  

Microsoft Academic Search

BACKGROUND: Interaction with integrin and focal adhesion kinase (FAK) regulates the cancer cell adhesion and invasion into extracellular matrix (ECM). In addition, phosphorylation of FAK correlates with the increase of cell motility and invasion. Adhesion and spreading of cancer cells on a variety of ECM proteins, including collagen type IV (Coll IV), leads to an increase in tyrosine phosphorylation and

Hirozumi Sawai; Yuji Okada; Hitoshi Funahashi; Yoichi Matsuo; Hiroki Takahashi; Hiromitsu Takeyama; Tadao Manabe

2005-01-01

344

L1 cell adhesion molecule promotes resistance to alcohol-induced silencing of growth cone responses to guidance cues.  

PubMed

Alcohol exposure in utero is a common cause of mental retardation, but the targets and mechanisms of action are poorly understood. Several lines of data point toward alterations in cortical connectivity, suggesting that axon guidance may be vulnerable to alcohol exposure. To test this, we asked whether ethanol directly affects cortical axonal growth cone responses to guidance cues. We find that even low concentrations of ethanol (12.5 mM; 57.2 mg/dl) commonly observed in social drinking prevent growth cone responses to three mechanistically independent guidance cues, Semaphorin3A, Lysophosphatidic Acid, and Netrin-1. However, this effect is highly dependent on substrate; axonal growth cones extending on an L1 cell adhesion molecule (L1CAM) substrate retain responsiveness to cues following exposure to ethanol, while those growing on poly-L-lysine or N-cadherin do not. The effects of ethanol on axon extension are, by contrast, quite modest. Quantitative assessments of the effects of ethanol on the surface distribution of L1CAM in growth cones suggest that L1CAM homophilic interactions may be particularly relevant for retaining growth cone responsiveness following ethanol exposure. Together, our findings indicate that ethanol can directly and generally alter growth cone responses to guidance cues, that a substrate of L1CAM effectively antagonizes this effect, and that cortical axonal growth cone vulnerability to ethanol may be predicted in part based on the environment through which they are extending. PMID:21335065

Sepulveda, B; Carcea, I; Zhao, B; Salton, S R J; Benson, D L

2011-04-28

345

Flexibilized Copolyimide Adhesives  

Microsoft Academic Search

Two copolyimides, LARC-STPI and STPI-LARC-2, with flexible backbones were prepared and characterized as adhesives. The processability and adhesive properties were compared to those of a commercially available form of LARC-TPI.Lap shear specimens were fabricated using adhesive tape prepared from each of the three polymers. Lap shear tests were performed at room temperature, 177°C, and 204°C before and after exposure to

Donald J. Progar; Terry L. St. Clair

1987-01-01

346

Biochemical investigations of retinotectal adhesive specificity  

PubMed Central

The preferential adhesion of chick neural retina cells to surfaces of intact optic tecta has been investigated biochemically. The study uses a collection assay in which single cells from either dorsal or ventral halves of neural retain adhere preferentially to ventral or dorsal halves of optic tecta respectively. The data presented support the following conclusions: (a) The adhesion of ventral retina to dorsal tecta seems to depend on proteins located on ventral retina and on terminal ?-N-acetylgalactosamine residues on dorsal tecta. (b) The adhesion of dorsal retina to ventral tecta seems to depend on proteins located on ventral tecta and on terminal ?- N-acetylgalactosamine residues on dorsal retina. (c) A double gradient model for retinotectal adhesion along the dorsoventral axis is consistent with the data presented. The model utilizes only two complementary molecules. The molecule suggested to be concentrated dorsally in both retina and tectum seems to require terminal ?-N-acetylgalactosamine residues for adhesion. Its activity is not affected by protease. A molecule fitting these qualifications, the ganglioside GM(2), could not be detected in a gradient, but lecithin vesicles containing GM(2) adhered preferentially to ventral tectal surfaces. The second molecule, concentrated ventrally in both retina and tectum, is a protein and seems capable of binding terminal ?-N- acetylgalactosamine residues. One enzyme, UDP-galactose:GM(2) galactosyltransferase, has been found to be more concentrated in ventral retina than dorsal, but only by 30 percent. PMID:562348

Marchase, RB

1977-01-01

347

Adhesion at metal interfaces  

NASA Technical Reports Server (NTRS)

A basic adhesion process is defined, the theory of the properties influencing metallic adhesion is outlined, and theoretical approaches to the interface problem are presented, with emphasis on first-principle calculations as well as jellium-model calculations. The computation of the energies of adhesion as a function of the interfacial separation is performed; fully three-dimensional calculations are presented, and universality in the shapes of the binding energy curves is considered. An embedded-atom method and equivalent-crystal theory are covered in the framework of issues involved in practical adhesion.

Banerjea, Amitava; Ferrante, John; Smith, John R.

1991-01-01

348

Fibronectins-adhesive glycoproteins of cell surface and blood  

Microsoft Academic Search

A recently characterised class of adhesive, high molecular weight glycoproteins is present on the surfaces of cells, in connective tissue matrices, and in extracellular fluids. These proteins may have important roles in cellular adhesion, malignant transformation, reticuloendothelial system function, and embryonic differentiation.

Kenneth M. Yamada; Kenneth Olden

1978-01-01

349

The effects of relative humidity on lactose particle adhesion  

Microsoft Academic Search

Adhesion between protein and solid surface or between pharmaceutical particle and solid surface is one of the major concerns in many research areas and in industrial processes. Adhesion at an interface is the result of several interaction forces, including van der Waals interactions, electrostatic interactions, steric interactions, and chemical bonding. In this study, dextran is oxidized using standard periodate methods

Kyung Min Lee

2009-01-01

350

Fractionation of cottonseed flour for improving its adhesive properties  

Technology Transfer Automated Retrieval System (TEKTRAN)

As early as the 1950's, cottonseed flour (i. e. meal) was tested for use as wood adhesives. Recently, renewed interest exists in the use of plant proteins as wood adhesives, as these materials are renewable and biodegradable. In this research, we separated cottonseed flour into several fractions wit...

351

International Journal of Adhesion & Adhesives 28 (2007) 7790 Properties of adhesives and CPVC materials proposed  

E-print Network

International Journal of Adhesion & Adhesives 28 (2007) 77­90 Properties of adhesives and CPVC conditions. A total of 132 adhesive and CPVC tension coupons were examined under severe environmental were conducted to evaluate the shear strength of the adhesive using 50 CPVC- to-steel specimens

352

Tuning endothelial monolayer adhesion: a neutron reflectivity study  

PubMed Central

Endothelial cells, master gatekeepers of the cardiovascular system, line its inner boundary from the heart to distant capillaries constantly exposed to blood flow. Interendothelial signaling and the monolayers adhesion to the underlying collagen-rich basal lamina are key in physiology and disease. Using neutron scattering, we report the first ever interfacial structure of endothelial monolayers under dynamic flow conditions mimicking the cardiovascular system. Endothelial adhesion (defined as the separation distance ? between the basal cell membrane and solid boundary) is explained using developed interfacial potentials and intramembrane segregation of specific adhesion proteins. Our method provides a powerful tool for the biophysical study of cellular layer adhesion strength in living tissues. PMID:24163142

Junghans, Ann; Zebda, Noureddine; Birukov, Konstantin; Majewski, Jaroslaw

2013-01-01

353

Bacterial Adhesion at Synthetic Surfaces  

PubMed Central

A systematic investigation into the effect of surface chemistry on bacterial adhesion was carried out. In particular, a number of physicochemical factors important in defining the surface at the molecular level were assessed for their effect on the adhesion of Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, and Escherichia coli. The primary experiments involved the grafting of groups varying in hydrophilicity, hydrophobicity, chain length, and chemical functionality onto glass substrates such that the surfaces were homogeneous and densely packed with functional groups. All of the surfaces were found to be chemically well defined, and their measured surface energies varied from 15 to 41 mJ · m?2. Protein adsorption experiments were performed with 3H-labelled bovine serum albumin and cytochrome c prior to bacterial attachment studies. Hydrophilic uncharged surfaces showed the greatest resistance to protein adsorption; however, our studies also showed that the effectiveness of poly(ethyleneoxide) (PEO) polymers was not simply a result of its hydrophilicity and molecular weight alone. The adsorption of the two proteins approximately correlated with short-term cell adhesion, and bacterial attachment for L. monocytogenes and E. coli also correlated with the chemistry of the underlying substrate. However, for S. aureus and S. typhimurium a different pattern of attachment occurred, suggesting a dissimilar mechanism of cell attachment, although high-molecular-weight PEO was still the least-cell-adsorbing surface. The implications of this for in vivo attachment of cells suggest that hydrophilic passivating groups may be the best method for preventing cell adsorption to synthetic substrates provided they can be grafted uniformly and in sufficient density at the surface. PMID:10543814

Cunliffe, D.; Smart, C. A.; Alexander, C.; Vulfson, E. N.

1999-01-01

354

Molecular basis of growth cone adhesion: anchoring of adheron- containing filaments at adhesive loci  

PubMed Central

Adhesive contacts made by filopodia of neuronal growth cones are essential for proper neurite elongation and may have a role in the formation of synaptic junctions. Previously we described the appearance of filamentous materials extending from growth cone surfaces that seem to be associated with the strongly adhesive behavior of filopodia (Tsui, H.-C., K. L. Lankford, and W. L. Klein. 1985. Proc. Natl. Acad. Sci. USA. 82:8256-8260). Here, we have used immunogold labeling to determine whether known adhesive molecules might be localized at points of adhesion and possibly be constituents of the filamentous material. Antibodies to an adhesive molecule (neural cell adhesion molecule [N- CAM]) and to an adhesive macromolecular complex of proteins and proteoglycans (adheron) were localized at the EM level in whole mounts of cultured avian retina cells. Labeling of fixed cells showed that N- CAM and adheron molecules were both present on growth cones and on filopodia. However, filamentous materials extending from the cell surface were labeled with anti-adheron but not with anti-N-CAM. If cells were labeled before fixation, patches of anti-N-CAM labeling occurred in random areas over the growth cones, but adheron antibodies concentrated at points of apparent adhesion. Particularly dense clustering of anti-adheron occurred at individual filopodial tips and at points of contact between pairs of filopodia. The different patterns of labeling imply that N-CAMS do not associate with the main antigenic components of adheron on the membrane surface. Most importantly, the data indicate the N-CAMs were mobile in the membrane but that constituents of adherons were anchored at adhesive loci. An appealing hypothesis is that molecules found in adheron preparations have an important role in establishing the adhesive junctions formed by growth cone filopodia. PMID:3384855

1988-01-01

355

Adhesives Mixer Applicator  

NASA Technical Reports Server (NTRS)

Two-part adhesives are stored, mixed, and dispensed by an applicator originally developed for use aboard the Space Shuttle orbiter. Compressed gas furnishes energy for mixing and dispensing. An operator needs only to open pressure valve and pull a trigger on dispenser nozzle to apply adhesive.

Ramos, D. O.; Werner, K. E.

1982-01-01

356

Adhesive bonding of aluminum alloys  

SciTech Connect

The topics concerned with the European chromic acid anodize process, the sealed chromic acid anodize, the phosphoric acid anodize, surface analysis, and adhesive selection are discussed. Consideration is given to epoxy adhesives, elevated-temperature-resistant adhesives, the mechanical properties of adhesives, environmental/durability testing, and coatings. Data on the use of chemical analysis for control, the structural analysis of adhesive-bonded joints, tooling design and inspection, nondestructive inspection, and adhesive-bonded aluminum structure repair are presented.

Thrall, E.W.; Shannon, R.W.

1985-01-01

357

Factors influencing bacterial adhesion to contact lenses  

PubMed Central

The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria. PMID:22259220

Dutta, Debarun; Willcox, Mark

2012-01-01

358

Direct observation of ?-actinin tension and recruitment at focal adhesions during contact growth.  

PubMed

Adherent cells interact with extracellular matrix via cell-substrate contacts at focal adhesions. The dynamic assembly and disassembly of focal adhesions enables cell attachment, migration and growth. While the influence of mechanical forces on the formation and growth of focal adhesions has been widely observed, the force loading on specific proteins at focal adhesion complex is not clear. By co-expressing force sensitive ?-actinin FRET probes and fluorescence labeled paxillin in MDCK cells, we have simultaneously observed the time-dependent changes in tension in ?-actinin and the dynamics of focal adhesion during cell migration. We show that increase in tension in ?-actinin at the focal adhesion coincides with elongation of the adhesion in its growth phase. The enlargement of focal adhesion is through a force sensitive recruitment of ?-actinin and paxillin to the adhesion sites. Changes in ?-actinin tension and correlated relocation of ?-actinin in an active adhesion also guide the growth direction of the adhesion. The results support the model that cytoskeletal tension is coupled to focal adhesion via the linking protein, ?-actinin at the adhesion complex. Lysophosphatidic acid caused an immediate increase in ?-actinin tension followed by drastic focal adhesion formation and elongation. Application of Rho-ROCK inhibitor, Y27632, resulted in reversible reduction in tension in ?-actinin and disassociation of focal adhesion, suggesting the involvement of myosin-II mediated contractile force in the focal adhesion dynamics. These findings suggest that ?-actinin not only serves as a physical linker between cytoskeleton and integrin, but also participates in force transmission at adhesion sites to facilitate adhesion?s growth. PMID:25088253

Ye, Nannan; Verma, Deepika; Meng, Fanjie; Davidson, Michael W; Suffoletto, Kevin; Hua, Susan Z

2014-09-10

359

Adhesives in larynx repair.  

PubMed

Guinea pig laryngeal fractures were used as a model to compare the ease of application and effectiveness of the fibrinogen-adhesive system with the ease of application and effectiveness of cyanoacrylate glue and control fractures stinted with contralateral gelatin film. Seven fibrin adhesive-treated and two cyanoacrylate glue-treated guinea pigs were perfused after 60 and 35 days, respectively. The larynges were serial sectioned, and the wound sites were compared. The fibrinogen adhesive system was easier to dispense than cyanoacrylate glue, did not require a completely dry surface, and stabilized within 3 minutes. Cartilage segment alignment with focal, complete fracture healing and symmetrical chondrocyte proliferation were seen in fibrogen adhesive-stinted larynges. In the cyanoacrylate glue-treated larynges, there was no alignment and minimal, asymmetrical chondrocyte proliferation. Gelatin film-stinted controls exhibited similar features. Thus, fibrogen adhesive was easier to apply and more effectively bound laryngeal fractures than cyanoacrylate glue or gelatin film. PMID:2467154

Lyons, M B; Lyons, G D; Webster, D; Wheeler, V R

1989-04-01

360

Tissue adhesives in otorhinolaryngology  

PubMed Central

The development of medical tissue adhesives has a long history without finding an all-purpose tissue adhesive for clinical daily routine. This is caused by the specific demands which are made on a tissue adhesive, and the different areas of application. In otorhinolaryngology, on the one hand, this is the mucosal environment as well as the application on bones, cartilage and periphery nerves. On the other hand, there are stressed regions (skin, oral cavity, pharynx, oesophagus, trachea) and unstressed regions (middle ear, nose and paranasal sinuses, cranial bones). But due to the facts that adhesives can have considerable advantages in assuring surgery results, prevention of complications and so reduction of medical costs/treatment expenses, the search for new adhesives for use in otorhinolaryngology will be continued intensively. In parallel, appropriate application systems have to be developed for microscopic and endoscopic use. PMID:22073094

Schneider, Gerlind

2011-01-01

361

The chemistry of stalked barnacle adhesive (Lepas anatifera)  

PubMed Central

The results of the first chemical analysis of the adhesive of Lepas anatifera, a stalked barnacle, are presented. A variety of elements were identified in scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) of the adhesive, including Na, Mg, Ca, Cl, S, Al, Si, K and Fe; however, protein–metal interactions were not detected in Raman spectra of the adhesive. Elemental signatures from SEM-EDS of L. anatifera adhesive glands were less varied. Phosphorous was mostly absent in adhesive samples; supporting previous studies showing that phosphoserines do not play a significant role in adult barnacle adhesion. Disulfide bridges arising from Cys dimers were also investigated; Raman analysis showed weak evidence for S–S bonds in L. anatifera. In addition, there was no calcium carbonate signal in the attenuated total reflectance Fourier transform infrared spectra of L. anatifera adhesive, unlike several previous studies in other barnacle species. Significant differences were observed between the Raman spectra of L. anatifera and Balanus crenatus; these and a range of Raman peaks in the L. anatifera adhesive are discussed. Polysaccharide was detected in L. anatifera adhesive but the significance of this awaits further experiments. The results demonstrate some of the diversity within barnacle species in the chemistry of their adhesives. PMID:25657841

Jonker, Jaimie-Leigh; Morrison, Liam; Lynch, Edward P.; Grunwald, Ingo; von Byern, Janek; Power, Anne Marie

2015-01-01

362

The chemistry of stalked barnacle adhesive (Lepas anatifera).  

PubMed

The results of the first chemical analysis of the adhesive of Lepas anatifera, a stalked barnacle, are presented. A variety of elements were identified in scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) of the adhesive, including Na, Mg, Ca, Cl, S, Al, Si, K and Fe; however, protein-metal interactions were not detected in Raman spectra of the adhesive. Elemental signatures from SEM-EDS of L. anatifera adhesive glands were less varied. Phosphorous was mostly absent in adhesive samples; supporting previous studies showing that phosphoserines do not play a significant role in adult barnacle adhesion. Disulfide bridges arising from Cys dimers were also investigated; Raman analysis showed weak evidence for S-S bonds in L. anatifera. In addition, there was no calcium carbonate signal in the attenuated total reflectance Fourier transform infrared spectra of L. anatifera adhesive, unlike several previous studies in other barnacle species. Significant differences were observed between the Raman spectra of L. anatifera and Balanus crenatus; these and a range of Raman peaks in the L. anatifera adhesive are discussed. Polysaccharide was detected in L. anatifera adhesive but the significance of this awaits further experiments. The results demonstrate some of the diversity within barnacle species in the chemistry of their adhesives. PMID:25657841

Jonker, Jaimie-Leigh; Morrison, Liam; Lynch, Edward P; Grunwald, Ingo; von Byern, Janek; Power, Anne Marie

2015-02-01

363

Self-Assembly and Adhesion of DOPA-Modified Methacrylic Triblock Hydrogels  

E-print Network

and durable bonds in wet environments. Adhesive materials inspired by marine mussels are particularly based on mussel adhesive proteins (MAPs) that harden and form water-resistant bonds within a few seconds the proposed bonding mechanisms.11 There have been several efforts to mimic the water-resistant adhesive

364

DOI: 10.1002/cbic.200900425 Potent Fluoro-oligosaccharide Probes of Adhesion in  

E-print Network

DOI: 10.1002/cbic.200900425 Potent Fluoro-oligosaccharide Probes of Adhesion in Toxoplasmosis Sarah-called micronemal proteins (MICs) that mediate this first-phase adhesion not only by direct binding to host cell sur), as putative ligands and shown that these are recognised by the microneme adhesive repeat (MAR) domains of Tg

Davis, Ben G.

365

The Two-Pathway Model for the Catch-Slip Transition in Biological Adhesion  

E-print Network

The Two-Pathway Model for the Catch-Slip Transition in Biological Adhesion Yuriy V. Pereverzev. (1) in a mathematical description of membrane-to- surface adhesion and detachment. In this work adhesion protein FimH was shown to undergo a force-induced conformational change that led to stronger

366

Lateral clustering of the adhesive ectodomain: a fundamental determinant of cadherin function  

Microsoft Academic Search

Background: Classical cadherin-based cellular adhesion is mediated by a multicomponent protein complex that links the adhesive binding activity of the cadherin ectodomain to the actin cytoskeleton. Despite the importance of cadherins in morphogenesis and development, we know very little about how cells determine and alter cadherin adhesive strength. In this study, we sought to identify specific cellular mechanisms that modulate

Alpha S. Yap; William M. Brieher; Martin Pruschy; Barry M. Gumbiner

1997-01-01

367

Nascent Focal Adhesions Are Responsible for the Generation of Strong Propulsive Forces in Migrating Fibroblasts  

Microsoft Academic Search

Fibroblast migration involves complex me- chanical interactions with the underlying substrate. Al- though tight substrate contact at focal adhesions has been studied for decades, the role of focal adhesions in force transduction remains unclear. To address this ques- tion, we have mapped traction stress generated by fibro- blasts expressing green fluorescent protein (GFP)-zyxin. Surprisingly, the overall distribution of focal adhesions

Karen A. Beningo; Micah Dembo; Irina Kaverina; J. Victor Small; Yu-li Wang

2001-01-01

368

Signaling during platelet adhesion and activation  

PubMed Central

Upon vascular injury, platelets are activated by adhesion to adhesive proteins like von Willebrand factor and collagen, or by soluble platelet agonists like ADP, thrombin, and thromboxane A2. These adhesive proteins and soluble agonists induce signal transduction via their respective receptors. The various receptor-specific platelet activation signaling pathways converge into common signaling events, which stimulate platelet shape change, granule secretion, and ultimately induce the “inside-out” signaling process leading to activation of the ligand binding function of integrin ?IIb?3. Ligand binding to integrin ?IIb?3 mediates platelet adhesion and aggregation and triggers “outside-in” signaling, resulting in platelet spreading, additional granule secretion, stabilization of platelet adhesion and aggregation, and clot retraction. It has become increasingly evident that agonist-induced platelet activation signals also crosstalk with integrin “outside-in” signals to regulate platelet responses. Platelet activation involves a series of rapid positive feedback loops that greatly amplify initial activation signals, and enable robust platelet recruitment and thrombus stabilization. Recent studies have provided novel insight into the molecular mechanisms of these processes. PMID:21071698

Li, Zhenyu; Delaney, M. Keegan; O’Brien, Kelly A.; Du, Xiaoping

2011-01-01

369

Spectroscopic and morphologic characterization of the dentin/adhesive interface  

NASA Astrophysics Data System (ADS)

The potential environmental risks associated with mercury release have forced many European countries to ban the use of dental amalgam. Alternative materials such as composite resins do not provide the clinical function for the length of time characteristically associated with dental amalgam. The weak link in the composite restoration is the dentin/adhesive bond. The purpose of this study was to correlate morphologic characterization of the dentin/adhesive bond with chemical analyses using micro- Fourier transform infrared and micro-Raman spectroscopy. A commercial dental adhesive was placed on dentin substrates cut from extracted, unerupted human third molars. Sections of the dentin/adhesive interface were investigated using infrared radiation produced at the Aladdin synchrotron source; visible radiation from a Kr+ laser was used for the micro-Raman spectroscopy. Sections of the dentin/adhesive interface, differentially stained to identify protein, mineral, and adhesive, were examined using light microscopy. Due to its limited spatial resolution and the unknown sample thickness the infrared results cannot be used quantitatively in determining the extent of diffusion. The results from the micro-Raman spectroscopy and light microscopy indicate exposed protein at the dentin/adhesive interface. Using a laser that reduces background fluorescence, the micro-Raman spectroscopy provides quantitative chemical and morphologic information on the dentin/adhesive interface. The staining procedure is sensitive to sites of pure protein and thus, complements the Raman results.

Lemor, R. M.; Kruger, Michael B.; Wieliczka, David M.; Swafford, Jim R.; Spencer, Paulette

1999-01-01

370

Enzymatically cross-linked hydrogels and their adhesive  

E-print Network

of applications including sustained drug delivery, medical and dental adhesives, tissue repair and engineering-linking of proteins through the formation of e-(c-glutamyl)lysine isopeptide side-chain bridges (scheme 1). When

371

Disturbed homeostasis of lung intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 during sepsis.  

PubMed

Cecal ligation and puncture (CLP)-induced sepsis in mice was associated with perturbations in vascular adhesion molecules. In CLP mice, lung vascular binding of (125)I-monoclonal antibodies to intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 revealed sharp increases in binding of anti-ICAM-1 and significantly reduced binding of anti-VCAM-1. In whole lung homogenates, intense ICAM-1 up-regulation was found (both in mRNA and in protein levels) during sepsis, whereas very little increase in VCAM-1 could be measured although some increased mRNA was found. During CLP soluble VCAM-1 (sVCAM-1) and soluble ICAM-1 (sICAM-1) appeared in the serum. When mouse dermal microvascular endothelial cells (MDMECs) were incubated with serum from CLP mice, constitutive endothelial VCAM-1 fell in association with the appearance of sVCAM-1 in the supernatant fluids. Under the same conditions, ICAM-1 cell content increased in MDMECs. When MDMECs were evaluated for leukocyte adhesion, exposure to CLP serum caused increased adhesion of neutrophils and decreased adhesion of macrophages and T cells. The progressive build-up in lung myeloperoxidase after CLP was ICAM-1-dependent and independent of VLA-4 and VCAM-1. These data suggest that sepsis disturbs endothelial homeostasis, greatly favoring neutrophil adhesion in the lung microvasculature, thereby putting the lung at increased risk of injury. PMID:15039231

Laudes, Ines J; Guo, Ren-Feng; Riedemann, Niels C; Speyer, Cecilia; Craig, Ron; Sarma, J Vidya; Ward, Peter A

2004-04-01

372

Controlled spatial and conformational display of immobilised bone morphogenetic protein-2 and osteopontin signalling motifs regulates osteoblast adhesion and differentiation in vitro  

Microsoft Academic Search

BACKGROUND: The interfacial molecular mechanisms that regulate mammalian cell growth and differentiation have important implications for biotechnology (production of cells and cell products) and medicine (tissue engineering, prosthetic implants, cancer and developmental biology). We demonstrate here that engineered protein motifs can be robustly displayed to mammalian cells in vitro in a highly controlled manner using a soluble protein scaffold designed

Elizabeth A Mitchell; Benjamin T Chaffey; Andrew W McCaskie; Jeremy H Lakey; Mark A Birch

2010-01-01

373

Desmosomal adhesion in vivo.  

PubMed

Desmosomes are intercellular junctions that provide strong adhesion or hyper-adhesion in tissues. Here, we discuss the molecular and structural basis of this with particular reference to the desmosomal cadherins (DCs), their isoforms and evolution. We also assess the role of DCs as regulators of epithelial differentiation. New data on the role of desmosomes in development and human disease, especially wound healing and pemphigus, are briefly discussed, and the importance of regulation of the adhesiveness of desmosomes in tissue dynamics is considered. PMID:24460202

Berika, Mohamed; Garrod, David

2014-02-01

374

Stuck on You: Adhesion  

NSDL National Science Digital Library

Learners explore water adhesion and learn about why water molecules are more strongly attracted to some substances than others. In an investigation titled "Fabric Frenzy," learners use a magnifying glass to examine different fabrics and hypothesize whether each kind would be good for soaking up water. Learners then weigh the dry fabrics, predict how water will affect the weight of each sample, wet the samples, and weigh them again to see how much water they in fact absorb. Learners also examine other liquids and compare their adhesion to water adhesion.

New Jersey

2006-01-01

375

Adhesive Contact Sweeper  

NASA Technical Reports Server (NTRS)

Adhesive contact sweeper removes hair and particles vacuum cleaner leaves behind, without stirring up dust. Also cleans loose rugs. Sweeper holds commercially available spools of inverted adhesive tape. Suitable for use in environments in which air kept free of dust; optics laboratories, computer rooms, and areas inhabited by people allergic to dust. For carpets, best used in tandem with vacuum cleaner; first pass with vacuum cleaner removes coarse particles, and second pass with sweeper extracts fine particles. This practice extends useful life of adhesive spools.

Patterson, Jonathan D.

1993-01-01

376

Pervanadate-induced adhesion of CD4+ T cell to fibronectin is associated with tyrosine phosphorylation of paxillin.  

PubMed

The initial stages of T cell activation involve tyrosine protein kinase-mediated intracellular signaling events. Integrin-mediated adhesion of CD4+ T lymphocytes to extracellular matrix glycoproteins, such as fibronectin, is an activation-dependent process. The involvement of tyrosine protein kinases in the adhesion of CD4+ T cells to fibronectin was examined using pervanadate, a protein-tyrosine phosphatase inhibitor. Pervanadate induced the adhesion of human CD4+ T cells to immobilized fibronectin in a beta1 integrin-mediated fashion, and adhesion was associated with an increase of protein tyrosine phosphorylation. Tyrosine protein kinase inhibitors abrogated both T cell adhesion and intracellular protein tyrosine phosphorylation. Participation of cytoskeletal proteins in the pervanadate-induced T cell adhesion was indicated because cytoskeleton disruption by cytochalasin B inhibited cell adhesion to fibronectin. We demonstrate that the cytoskeletal protein paxillin underwent time-dependent tyrosine phosphorylation simultaneously with pervanadate-induced T cell adhesion to fibronectin. Tyrosine phosphorylation of paxillin was related to cell adhesion, since pretreatment of T cells with cytochalasin B abrogated both adhesion and phosphorylation. This study demonstrates a correlation between activation of protein tyrosine kinases, tyrosine phosphorylation of paxillin, and integrin-mediated T cell adhesion to extracellular matrix glycoproteins. PMID:9307082

Miron, S; Kachalsky, S G; Hershkoviz, R; Lider, O

1997-09-01

377

The clinical performance of adhesives  

Microsoft Academic Search

Objectives: Traditional mechanical methods of retaining restorative materials have been replaced to a large extent by tooth conserving adhesive restorative techniques. Because adhesives have been evolving so rapidly for the last few years, the timing is right for evaluating the clinical status of present day adhesives.Data sources: Current literature with regard to the clinical performance of adhesives has been reviewed.

B. Van Meerbeek; J. Perdigão; P. Lambrechts; G. Vanherle

1998-01-01

378

Discriminatory bio-adhesion over nano-patterned polymer brushes  

NASA Astrophysics Data System (ADS)

Surfaces functionalized with bio-molecular targeting agents are conventionally used for highly-specific protein and cell adhesion. This thesis explores an alternative approach: Small non-biological adhesive elements are placed on a surface randomly, with the rest of the surface rendered repulsive towards biomolecules and cells. While the adhesive elements themselves, for instance in solution, typically exhibit no selectivity for various compounds within an analyte suspension, selective adhesion of targeted objects or molecules results from their placement on the repulsive surface. The mechanism of selectivity relies on recognition of length scales of the surface distribution of adhesive elements relative to species in the analyte solution, along with the competition between attractions and repulsions between various species in the suspension and different parts of the collecting surface. The resulting binding selectivity can be exquisitely sharp; however, complex mixtures generally require the use of multiple surfaces to isolate the various species: Different components will be adhered, sharply, with changes in collector composition. The key feature of these surface designs is their lack of reliance on biomolecular fragments for specificity, focusing entirely on physicochemical principles at the lengthscales from 1 - 100 nm. This, along with a lack of formal patterning, provides the advantages of simplicity and cost effectiveness. This PhD thesis demonstrates these principles using a system in which cationic poly-L-lysine (PLL) patches (10 nm) are deposited randomly on a silica substrate and the remaining surface is passivated with a bio-compatible PEG brush. TIRF microscopy revealed that the patches were randomly arranged, not clustered. By precisely controlling the number of patches per unit area, the interfaces provide sharp selectivity for adhesion of proteins and bacterial cells. For instance, it was found that a critical density of patches (on the order of 1000/mum 2) was required for fibrinogen adsorption while a greater density comprised the adhesion threshold for albumin. Surface compositions between these two thresholds discriminated binding of the two proteins. The binding behavior of the two proteins from a mixture was well anticipated by the single- protein binding behaviors of the individual proteins. The mechanism for protein capture was shown to be multivalent: protein adhesion always occurred for averages spacings of the adhesive patches smaller than the dimensions of the protein of interest. For some backfill brush architectures, the spacing between the patches at the threshold for protein capture clearly corresponded to the major dimension of the target protein. For more dense PEG brush backfills however, larger adhesion thresholds were observed, corresponding to greater numbers of patches involved with the adhesion of each protein molecule. . The thesis demonstrates the tuning of the position of the adhesion thresholds, using fibrinogen as a model protein, using variations in brush properties and ionic strength. The directions of the trends indicate that the brushes do indeed exert steric repulsions toward the proteins while the attractions are electrostatic in nature. The surfaces also demonstrated sharp adhesion thresholds for S. Aureus bacteria, at smaller concentrations of adhesive surfaces elements than those needed for the protein capture. The results suggest that bacteria may be captured while proteins are rejected from these surfaces, and there may be potential to discriminate different bacterial types. Such discrimination from protein-containing bacterial suspensions was investigated briefly in this thesis using S. Aureus and fibrinogen as a model mixture. However, due to binding of fibrinogen to the bacterial surface, the separation did not succeed. It is still expected, however, that these surfaces could be used to selectively capture bacteria in the presence of non-interacting proteins<