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1

ADAM-10-Mediated N-cadherin Cleavage is Protein Kinase C-?-Dependent and Promotes Glioblastoma Cell Migration  

PubMed Central

Matrix metalloproteinases (MMPs) and the related ‘a disintegrin and metalloproteinases’ (ADAMs) promote tumorigenesis by cleaving extracellular matrix and protein substrates, including N-cadherin. While N-cadherin is thought to regulate cell adhesion, migration and invasion, its role has not been characterized in glioblastomas (GBMs). In this study, we investigated the expression and function of post-translational N-cadherin cleavage in GBM cells as well as its regulation by protein kinase C (PKC). N-cadherin cleavage occurred at a higher level in glioblastoma cells than in non-neoplastic astrocytes. Treatment with the PKC-activator phorbol 12-myristate 13-acetate (PMA) increased N-cadherin cleavage, which was reduced by pharmacological inhibitors and siRNA specific for ADAM-10 or PKC-?. Furthermore, treatment of GBM cells with PMA induced the translocation of ADAM-10 to the cell membrane, the site where N-cadherin was cleaved, and this translocation was significantly reduced by the PKC-? inhibitor Gö6976 or PKC-? shRNA. In functional studies, N-cadherin cleavage was required for GBM cell migration, as depletion of N-cadherin cleavage by N-cadherin siRNA, ADAM-10 siRNA, or a cleavage-site mutant N-cadherin, decreased GBM cell migration. Taken together, these results suggest that N-cadherin cleavage is regulated by a PKC-?-ADAM-10 cascade in GBM cells and may be involved in mediating GBM cell migration. PMID:19357285

Kohutek, Zachary A.; diPierro, Charles G.; Redpath, Gerard T.; Hussaini, Isa M.

2009-01-01

2

Analysis of APC, ?-, ?-catenins, and N-cadherin protein expression in aggressive fibromatosis (desmoid tumor)  

Microsoft Academic Search

The aims of this study were to analyze the cadherin\\/catenin adhesion complex in cells from abdominal and extra-abdominal aggressive fibromatosis tumors, and to estimate the correlation between the expression of the tested proteins and the clinical data of the desmoid patients.Immunohistochemistry was used to examine the expression of the cadherin\\/catenin adhesion complex: APC protein, ?-, ?-catenin, and N-cadherin in archival

Tomasz Ferenc; Jan Wojciech Wro?ski; Janusz Kopczy?ski; Andrzej Kulig; Ma?gorzata Sidor; Liliana Stali?ska; Adam Dziki; Jacek Sygut

2009-01-01

3

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

Microsoft Academic Search

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

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

1998-01-01

4

Expression of N-cadherin by human squamous carcinoma cells induces a scattered fibroblastic phenotype with disrupted cell-cell adhesion  

PubMed Central

E-cadherin is a transmembrane glycoprotein that mediates calcium- dependent, homotypic cell-cell adhesion and plays an important role in maintaining the normal phenotype of epithelial cells. Disruption of E- cadherin activity in epithelial cells correlates with formation of metastatic tumors. Decreased adhesive function may be implemented in a number of ways including: (a) decreased expression of E-cadherin; (b) mutations in the gene encoding E-cadherin; or (c) mutations in the genes that encode the catenins, proteins that link the cadherins to the cytoskeleton and are essential for cadherin mediated cell-cell adhesion. In this study, we explored the possibility that inappropriate expression of a nonepithelial cadherin by an epithelial cell might also result in disruption of cell-cell adhesion. We showed that a squamous cell carcinoma-derived cell line expressed N-cadherin and displayed a scattered fibroblastic phenotype along with decreased expression of E- and P-cadherin. Transfection of this cell line with antisense N- cadherin resulted in reversion to a normal-appearing squamous epithelial cell with increased E- and P-cadherin expression. In addition, transfection of a normal-appearing squamous epithelial cell line with N-cadherin resulted in downregulation of both E- and P- cadherin and a scattered fibroblastic phenotype. In all cases, the levels of expression of N-cadherin and E-cadherin were inversely related to one another. In addition, we showed that some squamous cell carcinomas expressed N-cadherin in situ and those tumors expressing N- cadherin were invasive. These studies led us to propose a novel mechanism for tumorigenesis in squamous epithelial cells; i.e., inadvertent expression of a nonepithelial cadherin. PMID:8978829

1996-01-01

5

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

PubMed Central

Background Venous leg ulcers can be very hard to heal and represent a significant medical need with no effective therapeutic treatment currently available. Principal Findings In wound edge biopsies from human venous leg ulcers we found a striking upregulation of dermal N-cadherin, Zonula Occludens-1 and the gap junction protein Connexin43 (Cx43) compared to intact skin, and in stark contrast to the down-regulation of Cx43 expression seen in acute, healing wounds. We targeted the expression of these proteins in 3T3 fibroblasts to evaluate their role in venous leg ulcers healing. Knockdown of Cx43 and N-cadherin, but not Zonula Occludens-1, accelerated cell migration in a scratch wound-healing assay. Reducing Cx43 increased Golgi reorientation, whilst decreasing cell adhesion and proliferation. Furthermore, Connexin43 and N-cadherin knockdown led to profound effects on fibroblast cytoskeletal dynamics after scratch-wounding. The cells exhibited longer lamelipodial protrusions lacking the F-actin belt seen at the leading edge in wounded control cells. This phenotype was accompanied by augmented activation of Rac-1 and RhoA GTPases, as revealed by Förster Resonance Energy Transfer and pull down experiments. Conclusions Cx43 and N-cadherin are potential therapeutic targets in the promotion of healing of venous leg ulcers, by acting at least in part through distinct contributions of cell adhesion, migration, proliferation and cytoskeletal dynamics. PMID:22615994

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

2012-01-01

6

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

PubMed Central

Neural progenitors are organized as a pseudostratified epithelium held together by adherens junctions (AJs), multiprotein complexes composed of cadherins and ?- and ?-catenin. Catenins are known to control neural progenitor division; however, it is not known whether they function in this capacity as cadherin binding partners, as there is little evidence that cadherins themselves regulate neural proliferation. We show here that zebrafish N-cadherin (N-cad) restricts cell proliferation in the dorsal region of the neural tube by regulating cell-cycle length. We further reveal that N-cad couples cell-cycle exit and differentiation, as a fraction of neurons are mitotic in N-cad mutants. Enhanced proliferation in N-cad mutants is mediated by ligand-independent activation of Hedgehog (Hh) signaling, possibly caused by defective ciliogenesis. Furthermore, depletion of Hh signaling results in the loss of junctional markers. We therefore propose that N-cad restricts the response of dorsal neural progenitors to Hh and that Hh signaling limits the range of its own activity by promoting AJ assembly. Taken together, these observations emphasize a key role for N-cad–mediated adhesion in controlling neural progenitor proliferation. In addition, these findings are the first to demonstrate a requirement for cadherins in synchronizing cell-cycle exit and differentiation and a reciprocal interaction between AJs and Hh signaling. PMID:21389116

Chalasani, Kavita; Brewster, Rachel M.

2011-01-01

7

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

8

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

2012-01-01

9

Adhesive but not Signaling Activity of Drosophila N-cadherin is Essential for Target Selection of Photoreceptor Afferents  

PubMed Central

Drosophila N-cadherin (CadN) is an evolutionarily conserved, atypical classical cadherin, which has a large complex extracellular domain and a catenin-binding cytoplasmic domain. We have previously shown that CadN regulates target selection of R7 photoreceptor axons. To determine the functional domains of CadN, we conducted a structure-function analysis focusing on its in vitro adhesive activity and in vivo function in R7 growth cones. We found that the cytoplasmic domain of CadN is largely dispensable for the targeting of R7 growth cones, and it is not essential for mediating homophilic interaction in cultured cells. Instead, the cytoplasmic domain of CadN is required for maintaining proper growth cone morphology. Domain swapping with the extracellular domain of CadN2, a related but non-adhesive cadherin, revealed that the CadN extracellular domain is required for both adhesive activity and R7 targeting. Using a target-mosaic system, we generated CadN mutant clones in the optic lobe and examined the target-selection of genetically wild-type R7 growth cones to CadN mutant target neurons. We found that CadN, but neither LAR nor Liprin-?, is required in the medulla neurons for R7 growth cones to select sthe correct medulla layer. Together, these data suggest that CadN mediates homophilic adhesive interactions between R7 growth cones and medulla neurons to regulate layer-specific target selection. PMID:17320070

Yonekura, Shinichi; Xu, Lei; Ting, Chun-Yuan; Lee, Chi-Hon

2007-01-01

10

The cytoplasmic domain of N-cadherin modulates MMP?9 induction in oral squamous carcinoma cells.  

PubMed

Oral squamous carcinoma is the sixth most common cancer worldwide, and one of the most common cancers in developing countries. Regional and distant metastases comprise the majority of cases at initial diagnosis and correlate with poor patient outcomes. Oral epithelia is one of many tissue types to exhibit a cadherin switch during tumor progression, in which endogenous cell adhesion proteins, such as E-cadherin, give way to those of mesenchymal origin. The mesenchymal cell adhesion protein N-cadherin is found at the invading front of oral squamous carcinomas and has been strongly correlated with poor patient prognosis. The goal of the present study was to elucidate the mechanism by which N-cadherin may increase extracellular matrix-associated proteolytic activity to facilitate invasiveness in oral tumor development. The overexpression of N-cadherin in two oral squamous carcinoma cell lines increased motility, invasive capacity and synthesis of matrix metalloproteinase-9 (MMP-9) in a manner that was independent of E-cadherin downregulation. The use of EN and NE chimeric cadherin molecules with reciprocally substituted cytoplasmic domains revealed that optimal induction of MMP-9 synthesis required the cytoplasmic region, but not the extracellular region, of N-cadherin. Utilizing an N-cadherin mutant with impaired p120 binding ability, we found that such mutation resulted in a 4-fold decrease in motility compared to wild-type N-cadherin, but did not affect either MMP-9 expression or motility-normalized invasion. Overexpression of wild-type N-cadherin produced a 27-fold increase in the transcriptional activity of ?-catenin, concomitant with increases in MMP-9 transcription. These results suggest that N-cadherin may promote motility and invasiveness through distinct mechanisms, and that ?-catenin may be an integral mediator of N-cadherin-dependent invasive signaling in oral epithelia. PMID:25175499

Walker, Andrew; Frei, Rhett; Lawson, Kathryn R

2014-10-01

11

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

12

GRIP1 interlinks N-cadherin and AMPA receptors at vesicles to promote combined cargo transport into dendrites.  

PubMed

The GluA2 subunit of AMPA-type glutamate receptors (AMPARs) regulates excitatory synaptic transmission in neurons. In addition, the transsynaptic cell adhesion molecule N-cadherin controls excitatory synapse function and stabilizes dendritic spine structures. At postsynaptic membranes, GluA2 physically binds N-cadherin, underlying spine growth and synaptic modulation. We report that N-cadherin binds to PSD-95/SAP90/DLG/ZO-1 (PDZ) domain 2 of the glutamate receptor interacting protein 1 (GRIP1) through its intracellular C terminus. N-cadherin and GluA2-containing AMPARs are presorted to identical transport vesicles for dendrite delivery, and live imaging reveals cotransport of both proteins. The kinesin KIF5 powers GluA2/N-cadherin codelivery by using GRIP1 as a multilink interface. Notably, GluA2 and N-cadherin use different PDZ domains on GRIP1 to simultaneously bind the transport complex, and interference with either binding motif impairs the turnover of both synaptic cargoes. Depolymerization of microtubules, deletion of the KIF5 motor domain, or specific blockade of AMPAR exocytosis affects delivery of GluA2/N-cadherin vesicles. At the functional level, interference with this cotransport reduces the number of spine protrusions and excitatory synapses. Our data suggest the concept that the multi-PDZ-domain adaptor protein GRIP1 can act as a scaffold at trafficking vesicles in the combined delivery of AMPARs and N-cadherin into dendrites. PMID:24639525

Heisler, Frank F; Lee, Han Kyu; Gromova, Kira V; Pechmann, Yvonne; Schurek, Beate; Ruschkies, Laura; Schroeder, Markus; Schweizer, Michaela; Kneussel, Matthias

2014-04-01

13

Wnt5a influences viability, migration, adhesion, colony formation, E- and N-cadherin expression of human ovarian cancer cell line SKOV-3.  

PubMed

Epithelial ovarian cancer (EOC) cells express Wnt5a, but its role in ovarian cancer progression is poorly defined. The aims of the present study were two-fold: 1) to determine the Wnt5a role in viability, apoptosis, migration, colony formation and adhesion of human serous epithelial ovarian cancer cell line SKOV-3, and 2) to assess the relationship of Wnt5a with E- and N-cadherin in high- and low-grade human serous ovarian cancer specimens. Wnt5a over-expression led to 29% increased serum-independent cell viability (P < 0.05) and 35% decreased caspase-3 activity (P < 0.01) compared to SKOV-3 cells. There was 96% (P < 0.001) increased cell motility in Wnt5a-transfected SKOV-3 (SKOV-3/Wnt5a) cells compared to SKOV-3, which was abrogated in the presence of JNK inhibitor. In addition, there was about 42% increased cell adhesion to Matrigel compared to SKOV-3 cells (P < 0.001). Colony-forming assay showed a 4.4-fold increased colony formation in SKOV-3/Wnt5a cells compared to SKOV-3 cells (P < 0.001). E- and N-cadherin levels were reduced by 49 % and 67 % in SKOV-3/Wnt5a cells compared to mock cells, respectively. Wnt5a and E-cadherin immunoexpression was significantly (P < 0.001) different in low-grade serous ovarian cancer (LGSC) and high-grade serous ovarian cancer (HGSC). In HGSC specimens, strong immunoexpression of Wnt5a was detected compared to LGSC. However, E-cadherin showed moderate immunostaining (84 %) in HGSC, whereas 100 % of LGSC specimens showed strong immunoexpression. In both groups no N-cadherin immunoexpression was detected. Moreover, Wnt5a showed a positive relationship with E-cadherin in the LGSC group (r = 0.661, P = 0.027). These results may support important roles for Wnt5a in EOC progression. PMID:24785108

Jannesari-Ladani, F; Hossein, G; Monhasery, N; Shahoei, S H; Izadi Mood, N

2014-01-01

14

N-cadherin regulates molecular organization of excitatory and inhibitory synaptic circuits in adult hippocampus in vivo.  

PubMed

N-Cadherin and ?-catenin form a transsynaptic adhesion complex required for spine and synapse development. In adulthood, N-cadherin mediates persistent synaptic plasticity, but whether the role of N-cadherin at mature synapses is similar to that at developing synapses is unclear. To address this, we conditionally ablated N-cadherin from excitatory forebrain synapses in mice starting in late postnatal life and examined hippocampal structure and function in adulthood. In the absence of N-cadherin, ?-catenin levels were reduced, but numbers of excitatory synapses were unchanged, and there was no impact on number or shape of dendrites or spines. However, the composition of synaptic molecules was altered. Levels of GluA1 and its scaffolding protein PSD95 were diminished and the density of immunolabeled puncta was decreased, without effects on other glutamate receptors and their scaffolding proteins. Additionally, loss of N-cadherin at excitatory synapses triggered increases in the density of markers for inhibitory synapses and decreased severity of hippocampal seizures. Finally, adult mutant mice were profoundly impaired in hippocampal-dependent memory for spatial episodes. These results demonstrate a novel function for the N-cadherin/?-catenin complex in regulating ionotropic receptor composition of excitatory synapses, an appropriate balance of excitatory and inhibitory synaptic proteins and the maintenance of neural circuitry necessary to generate flexible yet persistent cognitive and synaptic function. PMID:24753442

Nikitczuk, Jessica S; Patil, Shekhar B; Matikainen-Ankney, Bridget A; Scarpa, Joseph; Shapiro, Matthew L; Benson, Deanna L; Huntley, George W

2014-08-01

15

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

16

Suppression of the TGF-?1-induced protein expression of SNAI1 and N-cadherin by miR-199a.  

PubMed

MicroRNA miR-199a is clustered with miR-214 on chromosome 1 and its expression is up-regulated by various factors that are associated with epithelial-to-mesenchymal transition (EMT), such as a transcriptional repressor Twist1 and transforming growth factor (TGF)-?. miR-199a is either up-regulated or down-regulated in a variety of cancers, although EMT is associated with the progression of cancer. We found here that miR-199a suppressed the translation of SNAI1, a transcriptional repressor that plays a role in EMT, by targeting the sequence within the 3'UTR of the SNAI1 mRNA, and reduced the protein level of SNAI1. miR-199a increased the protein level of claudin-1 in both the TGF-?1-treated and -untreated cells at least partly by decreasing the protein level of SNAI1, a transcriptional repressor for claudin-1. In addition, miR-199a targeted the sequence within the 3'UTR of the N-cadherin mRNA and suppressed the TGF-?1-induced increase in the protein level of N-cadherin in a manner independent of SNAI1. These results indicate that miR-199a suppresses the TGF-?1-induced protein expression of SNAI1 and N-cadherin. PMID:25041364

Suzuki, Toshihiro; Mizutani, Kiyohito; Minami, Akihiro; Nobutani, Kentaro; Kurita, Souichi; Nagino, Masato; Shimono, Yohei; Takai, Yoshimi

2014-09-01

17

E- and N-Cadherin Distribution in Developing and Functional Human Teeth under Normal and Pathological Conditions  

PubMed Central

Cadherins are calcium-dependent cell adhesion molecules involved in the regulation of various biological processes such as cell recognition, intercellular communication, cell fate, cell polarity, boundary formation, and morphogenesis. Although previous studies have shown E-cadherin expression during rodent or human odontogenesis, there is no equivalent study available on N-cadherin expression in dental tissues. Here we examined and compared the expression patterns of E- and N-cadherins in both embryonic and adult (healthy, injured, carious) human teeth. Both proteins were expressed in the developing teeth during the cap and bell stages. E-cadherin expression in dental epithelium followed an apical-coronal gradient that was opposite to that observed for N-cadherin. E-cadherin was distributed in proliferating cells of the inner and outer enamel epithelia but not in differentiated cells such as ameloblasts, whereas N-cadherin expression was up-regulated in differentiated epithelial cells. By contrast to E-cadherin, N-cadherin was also expressed in mesenchymal cells that differentiate into odontoblasts and produce the hard tissue matrix of dentin. Although N-cadherin was not detected in permanent intact teeth, it was re-expressed during dentin repair processes in odontoblasts surrounding carious or traumatic sites. Similarly, N-cadherin re-expression was seen in vitro, in cultured primary pulp cells that differentiate into odontoblast-like cells. Taken together these results suggest that E- and N-cadherins may play a role during human tooth development and, moreover, indicate that N-cadherin is important for odontoblast function in normal development and under pathological conditions. PMID:12057916

Heymann, Robert; About, Imad; Lendahl, Urban; Franquin, Jean-Claude; Obrink, Bjorn; Mitsiadis, Thimios A.

2002-01-01

18

Effect of di-(2-ethylhexyl) phthalate on N-cadherin and catenin protein expression in rat testis  

Microsoft Academic Search

This study investigated the effect of DEHP exposure on N-cadherin and ?-, ?- and p120-catenin immunoreactivities in the rat testis. DEHP was administered by daily gavage to 25-day-old male Sprague–Dawley rats at a dose of 2g DEHP\\/5ml corn oil\\/kg body weight for 2 days or 7 days. Control rats were treated with corn oil vehicle under the same conditions. Animals

Cristian M. Sobarzo; Livia Lustig; Roberto Ponzio; Berta Denduchis

2006-01-01

19

SMAD4 Regulates Cell Motility through Transcription of N-Cadherin in Human Pancreatic Ductal Epithelium  

PubMed Central

Expression of the cellular adhesion protein N-cadherin is a critical event during epithelial-mesenchymal transition (EMT). The SMAD4 protein has been identified as a mediator of transforming growth factor-? (TGF-?) superfamily signaling, which regulates EMT, but the mechanisms linking TGF-? signaling to N-cadherin expression remain unclear. When the TGF-? pathway is activated, SMAD proteins, including the common mediator SMAD4, are subsequently translocated into the nucleus, where they influence gene transcription via SMAD binding elements (SBEs). Here we describe a mechanism for control of CDH2, the gene encoding N-cadherin, through the canonical TGF?–SMAD4 pathway. We first identified four previously undescribed SBEs within the CDH2 promoter. Using telomerase immortalized human pancreatic ductal epithelium, we found that TGF-? stimulation prompted specific SMAD4 binding to all four SBEs. Luciferase reporter and SMAD4-knockdown experiments demonstrated that specific SMAD4 binding to the SBE located at ?3790 bp to ?3795 bp within the promoter region of CDH2 was necessary for TGF-?-stimulated transcription. Expression of N-cadherin on the surface of epithelial cells facilitates motility and invasion, and we demonstrated that knockdown of SMAD4 causes decreased N-cadherin expression, which results in diminished migration and invasion of human pancreatic ductal epithelial cells. Similar reduction of cell motility was produced after CDH2 knockdown. Together, these findings suggest that SMAD4 is critical for the TGF-?-driven upregulation of N-cadherin and the resultant invasive phenotype of human pancreatic ductal epithelial cells during EMT. PMID:25264609

Kang, Ya'an; Ling, Jianhua; Suzuki, Rei; Roife, David; Chopin-Laly, Xavier; Truty, Mark J.; Chatterjee, Deyali; Wang, Huamin; Thomas, Ryan M.; Katz, Matthew H.; Chiao, Paul J.; Fleming, Jason B.

2014-01-01

20

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.; Bruses, Juan L.

2012-01-01

21

Antagonistic roles of full-length N-cadherin and its soluble BMP cleavage product in neural crest delamination.  

PubMed

During neural crest ontogeny, an epithelial to mesenchymal transition is necessary for cell emigration from the dorsal neural tube. This process is likely to involve a network of gene activities, which remain largely unexplored. We demonstrate that N-cadherin inhibits the onset of crest delamination both by a cell adhesion-dependent mechanism and by repressing canonical Wnt signaling previously found to be necessary for crest delamination by acting downstream of BMP4. Furthermore, N-cadherin protein, but not mRNA, is normally downregulated along the dorsal tube in association with the onset of crest delamination, and we find that this process is triggered by BMP4. BMP4 stimulates cleavage of N-cadherin into a soluble cytoplasmic fragment via an ADAM10-dependent mechanism. Intriguingly, when overexpressed, the cytoplasmic N-cadherin fragment translocates into the nucleus, stimulates cyclin D1 transcription and crest delamination, while enhancing transcription of beta-catenin. CTF2 also rescues the mesenchymal phenotype of crest cells in ADAM10-inhibited neural primordia. Hence, by promoting its cleavage, BMP4 converts N-cadherin inhibition into an activity that is likely to participate, along with canonical Wnt signaling, in the stimulation of neural crest emigration. PMID:17185320

Shoval, Irit; Ludwig, Andreas; Kalcheim, Chaya

2007-02-01

22

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

23

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

24

N-cadherin promotes recruitment and migration of neural progenitor cells from the SVZ neural stem cell niche into demyelinated lesions.  

PubMed

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; Aguirre, Adan

2014-07-16

25

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

PubMed

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

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

2012-06-15

26

Expression of N-cadherin by human squamous carcinoma cells induces a scattered fibroblastic phenotype with disrupted cell-cell adhesion  

Microsoft Academic Search

E-cadherin is a transmembrane glycoprotein that mediates calcium-dependent, homotypic cell-cell adhesion and plays an important role in maintaining the normal phenotype of epithelial cells. Disruption of E-cadherin activity in epithelial cells correlates with formation of metastatic tumors. Decreased adhesive function may be implemented in a number of ways in- cluding: (a) decreased expression of E-cadherin; (b) mutations in the gene

Shahidul Islam; Thomas E. Carey; Gregory T. Wolf; Margaret J. Wheelock; Keith R. Johnson

1996-01-01

27

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

PubMed Central

This study addresses the role of glycogen synthase kinase (GSK)-3? signaling in the tumorigenic behavior of melanoma. Immunohistochemical staining revealed GSK3? to be focally expressed in the invasive portions of 12% and 33% of primary and metastatic melanomas, respectively. GSK3 inhibitors and siRNA knockdown of GSK3? were found to inhibit the motile behavior of melanoma cells in scratch wound, 3D collagen implanted spheroid and modified Boyden chamber assays. Functionally, inhibition of GSK3? signaling was found to suppress N-cadherin expression at the mRNA and protein levels and was associated with decreased expression of the transcription factor Slug. Pharmacological and genetic ablation of GSK3? signaling inhibited the adhesion of melanoma cells to both endothelial cells and fibroblasts and prevented transendothelial migration, an effect rescued by the forced overexpression of N-cadherin. A further role for GSK3? signaling in invasion was suggested by the ability of GSK3? inhibitors and siRNA knockdown to block phosphorylation of FAK and increase the size of focal adhesions. In summary, we have demonstrated a previously unreported role for GSK3? in modulating the motile and invasive behavior of melanoma cells through N-cadherin and FAK. These studies suggest the potential therapeutic utility of inhibiting GSK3? in defined subsets of melanoma. PMID:22810307

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

2012-01-01

28

AKT activation by N-cadherin regulates beta-catenin signaling and neuronal differentiation during cortical development  

PubMed Central

Background During cerebral cortical development, neural precursor-precursor interactions in the ventricular zone neurogenic niche coordinate signaling pathways that regulate proliferation and differentiation. Previous studies with shRNA knockdown approaches indicated that N-cadherin adhesion between cortical precursors regulates ?-catenin signaling, but the underlying mechanisms remained poorly understood. Results Here, with conditional knockout approaches, we find further supporting evidence that N-cadherin maintains ?-catenin signaling during cortical development. Using shRNA to N-cadherin and dominant negative N-cadherin overexpression in cell culture, we find that N-cadherin regulates Wnt-stimulated ?-catenin signaling in a cell-autonomous fashion. Knockdown or inhibition of N-cadherin with function-blocking antibodies leads to reduced activation of the Wnt co-receptor LRP6. We also find that N-cadherin regulates ?-catenin via AKT, as reduction of N-cadherin causes decreased AKT activation and reduced phosphorylation of AKT targets GSK3? and ?-catenin. Inhibition of AKT signaling in neural precursors in vivo leads to reduced ?-catenin-dependent transcriptional activation, increased migration from the ventricular zone, premature neuronal differentiation, and increased apoptotic cell death. Conclusions These results show that N-cadherin regulates ?-catenin signaling through both Wnt and AKT, and suggest a previously unrecognized role for AKT in neuronal differentiation and cell survival during cortical development. PMID:23618343

2013-01-01

29

N-cadherin impedes proliferation of the multiple myeloma cancer stem cells  

PubMed Central

Multiple myeloma (MM) is an incurable malignancy of the plasma cells localized to the bone marrow. A rare population of MM cancer stem cells (MM-CSCs) has been shown to be responsible for maintaining the pull of residual disease and to contribute to myeloma relapse. The stem cells are found in a bone marrow niche in contact with the stromal cells that are responsible for maintaining the proliferative quiescence of the MM-CSC and regulate its self-renewal and differentiation decisions. Here we show that both MM and bone marrow stromal cells express N-cadherin, a cell-cell adhesion molecule shown to maintain a pool of leukemic stem cells. Inhibition of N-cadherin using a neutralizing antibody led to an increase in the MM cell proliferation. A decrease in MM cell adhesion to the bone marrow stroma was observed in the first 24 hours of co-culture followed by a 2.3-30-fold expansion of the adherent cells. Moreover, inhibition of N-cadherin led to a 4.8-9.6-fold expansion of the MM-CSC population. Surprisingly, addition of the N-cadherin antagonist peptide resulted in massive death of the non-adherent MM cells, while the viability of the adherent cells and MM-CSCs remained unaffected. Interestingly, the proliferative effects of N-cadherin inhibition were not mediated by the nuclear translocation of ?-catenin. Taken together, our findings demonstrate the crucial role of N-cadherin in regulating MM cell proliferation and viability and open an interesting avenue of investigation to understand how structural modifications of N-cadherin can affect MM cell behavior. Our findings suggest that targeting N-cadherin may be a useful therapeutic strategy to treat MM in conjunction with an agent that has anti-MM-CSC activity. PMID:24396705

Sadler, Nicole M; Harris, Britney R; Metzger, Brittany A; Kirshner, Julia

2013-01-01

30

N-cadherin impedes proliferation of the multiple myeloma cancer stem cells.  

PubMed

Multiple myeloma (MM) is an incurable malignancy of the plasma cells localized to the bone marrow. A rare population of MM cancer stem cells (MM-CSCs) has been shown to be responsible for maintaining the pull of residual disease and to contribute to myeloma relapse. The stem cells are found in a bone marrow niche in contact with the stromal cells that are responsible for maintaining the proliferative quiescence of the MM-CSC and regulate its self-renewal and differentiation decisions. Here we show that both MM and bone marrow stromal cells express N-cadherin, a cell-cell adhesion molecule shown to maintain a pool of leukemic stem cells. Inhibition of N-cadherin using a neutralizing antibody led to an increase in the MM cell proliferation. A decrease in MM cell adhesion to the bone marrow stroma was observed in the first 24 hours of co-culture followed by a 2.3-30-fold expansion of the adherent cells. Moreover, inhibition of N-cadherin led to a 4.8-9.6-fold expansion of the MM-CSC population. Surprisingly, addition of the N-cadherin antagonist peptide resulted in massive death of the non-adherent MM cells, while the viability of the adherent cells and MM-CSCs remained unaffected. Interestingly, the proliferative effects of N-cadherin inhibition were not mediated by the nuclear translocation of ?-catenin. Taken together, our findings demonstrate the crucial role of N-cadherin in regulating MM cell proliferation and viability and open an interesting avenue of investigation to understand how structural modifications of N-cadherin can affect MM cell behavior. Our findings suggest that targeting N-cadherin may be a useful therapeutic strategy to treat MM in conjunction with an agent that has anti-MM-CSC activity. PMID:24396705

Sadler, Nicole M; Harris, Britney R; Metzger, Brittany A; Kirshner, Julia

2013-01-01

31

MT5-MMP, ADAM-10, and N-cadherin act in concert to facilitate synapse reorganization after traumatic brain injury.  

PubMed

Matrix metalloproteinases (MMPs) influence synaptic recovery following traumatic brain injury (TBI). Membrane type 5-matrix metalloproteinase (MT5-MMP) and a distintegrin and metalloproteinase-10 (ADAM-10) are membrane-bound MMPs that cleave N-cadherin, a protein critical to synapse stabilization. This study examined protein and mRNA expression of MT5-MMP, ADAM-10, and N-cadherin after TBI, contrasting adaptive and maladaptive synaptogenesis. The effect of MMP inhibition on MT5-MMP, ADAM-10, and N-cadherin was assessed during maladaptive plasticity and correlated with synaptic function. Rats were subjected to adaptive unilateral entorhinal cortical lesion (UEC) or maladaptive fluid percussion TBI+bilateral entorhinal cortical lesion (TBI+BEC). Hippocampal MT5-MMP and ADAM-10 protein was significantly elevated 2 and 7 days post-injury. At 15 days after UEC, each MMP returned to control level, while TBI+BEC ADAM-10 remained elevated. At 2 and 7 days, N-cadherin protein was below control. By the 15-day synapse stabilization phase, UEC N-cadherin rose above control, a shift not seen for TBI+BEC. At 7 days, increased TBI+BEC ADAM-10 transcript correlated with protein elevation. UEC ADAM-10 mRNA did not change, and no differences in MT5-MMP or N-cadherin mRNA were detected. Confocal imaging showed MT5-MMP, ADAM-10, and N-cadherin localization within reactive astrocytes. MMP inhibition attenuated ADAM-10 protein 15 days after TBI+BEC and increased N-cadherin. This inhibition partially restored long-term potentiation induction, but did not affect paired-pulse facilitation. Our results confirm time- and injury-dependent expression of MT5-MMP, ADAM-10, and N-cadherin during reactive synaptogenesis. Persistent ADAM-10 expression was correlated with attenuated N-cadherin level and reduced functional recovery. MMP inhibition shifted ADAM-10 and N-cadherin toward adaptive expression and improved synaptic function. PMID:22489706

Warren, Kelly M; Reeves, Thomas M; Phillips, Linda L

2012-07-01

32

MT5-MMP, ADAM-10, and N-Cadherin Act in Concert To Facilitate Synapse Reorganization after Traumatic Brain Injury  

PubMed Central

Abstract Matrix metalloproteinases (MMPs) influence synaptic recovery following traumatic brain injury (TBI). Membrane type 5-matrix metalloproteinase (MT5-MMP) and a distintegrin and metalloproteinase-10 (ADAM-10) are membrane-bound MMPs that cleave N-cadherin, a protein critical to synapse stabilization. This study examined protein and mRNA expression of MT5-MMP, ADAM-10, and N-cadherin after TBI, contrasting adaptive and maladaptive synaptogenesis. The effect of MMP inhibition on MT5-MMP, ADAM-10, and N-cadherin was assessed during maladaptive plasticity and correlated with synaptic function. Rats were subjected to adaptive unilateral entorhinal cortical lesion (UEC) or maladaptive fluid percussion TBI+bilateral entorhinal cortical lesion (TBI+BEC). Hippocampal MT5-MMP and ADAM-10 protein was significantly elevated 2 and 7 days post-injury. At 15 days after UEC, each MMP returned to control level, while TBI+BEC ADAM-10 remained elevated. At 2 and 7 days, N-cadherin protein was below control. By the 15-day synapse stabilization phase, UEC N-cadherin rose above control, a shift not seen for TBI+BEC. At 7 days, increased TBI+BEC ADAM-10 transcript correlated with protein elevation. UEC ADAM-10 mRNA did not change, and no differences in MT5-MMP or N-cadherin mRNA were detected. Confocal imaging showed MT5-MMP, ADAM-10, and N-cadherin localization within reactive astrocytes. MMP inhibition attenuated ADAM-10 protein 15 days after TBI+BEC and increased N-cadherin. This inhibition partially restored long-term potentiation induction, but did not affect paired-pulse facilitation. Our results confirm time- and injury-dependent expression of MT5-MMP, ADAM-10, and N-cadherin during reactive synaptogenesis. Persistent ADAM-10 expression was correlated with attenuated N-cadherin level and reduced functional recovery. MMP inhibition shifted ADAM-10 and N-cadherin toward adaptive expression and improved synaptic function. PMID:22489706

Warren, Kelly M.; Reeves, Thomas M.

2012-01-01

33

A role for the age?dependent loss of ?(E)?catenin in regulation of N?cadherin expression and cell migration  

PubMed Central

The aging kidney has a decreased ability to repair following acute kidney injury. Previous studies from our laboratory have demonstrated a loss in ??catenin expression in the aging rat kidney. We hypothesize that loss of ??catenin expression in tubular epithelial cells may induce changes that result in a decreased repair capacity. In these studies, we demonstrate that decreased ??catenin protein expression is detectable as early as 20 months of age in male Fischer 344 rats. Protein loss is also observed in aged nonhuman primate kidneys, suggesting that this is not a species?specific response. In an effort to elucidate alterations due to the loss of ??catenin, we generated NRK?52E cell lines with stable knockdown of ?(E)?catenin (C2 cells). Interestingly, C2 cells had decreased expression of N?cadherin, decreased cell–cell adhesion, and increased monolayer permeability. C2 had deficits in wound repair, due to alterations in cell migration. Analysis of gene expression in the migrating control cells indicated that expression of N?cadherin and N?CAM was increased during repair. In migrating C2 cells, expression of N?CAM was also increased, but the expression of N?cadherin was not upregulated. Importantly, a blocking antibody against N?cadherin inhibited repair in NRK?52E cells, suggesting an important role in repair. Taken together, these data suggest that loss of ??catenin, and the subsequent downregulation of N?cadherin expression, is a mechanism underlying the decreased migration of tubular epithelial cells that contributes to the inability of the aging kidney to repair following injury. PMID:24920123

Nichols, LaNita A.; Grunz?Borgmann, Elizabeth A.; Wang, Xinhui; Parrish, Alan R.

2014-01-01

34

Structure of the human N-cadherin gene: YAC analysis and fine chromosomal mapping to 18q11.2  

SciTech Connect

The cadherins are a large family of cell adhesion molecules involved in calcium-dependent recognition and adhesion events. The authors have used YAC analysis to determine the structure of the human N-cadherin gene. An 850-kb YAC was isolated and the entire N-cadherin gene mapped to a 250-kb region spanning three putative CpG islands. A PCR and cosmid subcloning strategy was used to define the boundaries for the 16 exons that compose the gene. These were shown to be not only highly conserved between mouse and human N-cadherin genes, but also similar to other cadherins. The first and second introns of the gene are large, a property conserved between the mouse and human genes. In situ hybridization with YAC DNA refined the map position of N-cadherin to human chromosome 18q11.2. 50 refs., 3 figs., 4 tabs.

Wallis, J.; Walsh, F.S. [Guy`s Hospital, London (United Kingdom)] [Guy`s Hospital, London (United Kingdom); Fox, M.F. [Galton Lab., London (United Kingdom)] [Galton Lab., London (United Kingdom)

1994-07-01

35

A CBP Binding Transcriptional Repressor Produced by the PS1\\/?-Cleavage of N-Cadherin Is Inhibited by PS1 FAD Mutations  

Microsoft Academic Search

Presenilin1 (PS1), a protein implicated in Alzheimer's disease (AD), forms complexes with N-cadherin, a transmembrane protein with important neuronal and synaptic functions. Here, we show that a PS1-dependent ?-secretase protease activity promotes an ?-like cleavage of N-cadherin to produce its intracellular domain peptide, N-Cad\\/CTF2. NMDA receptor agonists stimulate N-Cad\\/CTF2 production suggesting that this receptor regulates the ?-cleavage of N-cadherin. N-Cad\\/CTF2

Philippe Marambaud; Paul H Wen; Anindita Dutt; Junichi Shioi; Akihiko Takashima; Robert Siman; Nikolaos K Robakis

2003-01-01

36

N-cadherin is essential for retinoic acid-mediated cardiomyogenic differentiation in mouse embryonic stem cells.  

PubMed

Contraction forces developed by cardiomyocytes are transmitted across the plasma membrane through end-to-end connections between the myocytes, called intercalated disks, which enable the coordinated contraction of heart muscle. A component of the intercalated disk, the adherens junction, consists of the cell adhesion molecule, N-cadherin. Embryos lacking N-cadherin die at mid-gestation from cardiovascular abnormalities. We have evaluated the role of N-cadherin in cardiomyogenesis using N-cadherin-null mouse embryonic stem (ES) cells grown as embryoid bodies (EBs) in vitro. Myofibrillogenesis, the spatial orientation of myofibers, and intercellular contacts including desmosomes were normal in N-cadherin-null ES cell-derived cardiomyocytes. The effect of retinoic acid (RA), a stage and dose-dependent cardiogenic factor, was assessed in differentiating ES cells. all-trans (at) RA increased the number of ES cell-derived cardiomyocytes by approximately 3-fold (at 3 x 10(-9) M) in wt EBs. However, this effect was lost in N-cadherin-null EBs. In the presence of supplemented at-RA, the emergence of spontaneously beating cardiomyocytes appeared to be delayed and slightly less efficient in N-cadherin-null compared with wt and heterozygous EBs (frequencies of EBs with beating activity at 5 days: 54+/-18% vs. 96+/-0.5%, and 93+/-7%, respectively; peak frequencies of EBs with beating activity: 83+/-8% vs. 96+/-0.5% and 100%, respectively). In conclusion, cardiomyoyctes differentiating from N-cadherin-null ES cells in vitro show normal myofibrillogenesis and intercellular contacts, but impaired responses to early cardiogenic effects mediated by at-RA. These results suggest that N-cadherin may be essential for RA-induced cardiomyogenesis in mouse ES cells in vitro. PMID:17921113

Bugorsky, R; Perriard, J-C; Vassalli, G

2007-01-01

37

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.; Bruses, Juan L.

2010-01-01

38

Engineered N-cadherin and L1 biomimetic substrates concertedly promote neuronal differentiation, neurite extension and neuroprotection of human neural stem cells.  

PubMed

We investigated the design of neurotrophic biomaterial constructs for human neural stem cells, guided by neural developmental cues of N-cadherin and L1 adhesion molecules. Polymer substrates fabricated either as two-dimensional (2-D) films or three-dimensional (3-D) microfibrous scaffolds were functionalized with fusion chimeras of N-cadherin-Fc alone and in combination with L1-Fc, and the effects on differentiation, neurite extension and survival of H9 human-embryonic-stem-cell-derived neural stem cells (H9-NSCs) were quantified. Combinations of N-cadherin and L1-Fc co-operatively enhanced neuronal differentiation profiles, indicating the critical nature of the two complementary developmental cues. Notably, substrates presenting low levels of N-cadherin-Fc concentrations, combined with proportionately higher L1-Fc concentration, most enhanced neurite outgrowth and the degree of MAP2+ and neurofilament-M+ H9-NSCs. Low N-cadherin-Fc alone promoted improved cell survival following oxidative stress, compared to higher concentrations of N-cadherin-Fc alone or combinations with L1-Fc. Pharmacological and antibody blockage studies revealed that substrates presenting low levels of N-cadherin are functionally competent so long as they elicit a threshold signal mediated by homophilic N-cadherin and fibroblast growth factor signaling. Overall, these studies highlight the ability of optimal combinations of N-cadherin and L1 to recapitulate a "neurotrophic" microenvironment that enhances human neural stem cell differentiation and neurite outgrowth. Additionally, 3-D fibrous scaffolds presenting low N-cadherin-Fc further enhanced the survival of H9-NSCs compared to equivalent 2-D films. This indicates that similar biofunctionalization approaches based on N-cadherin and L1 can be translated to 3-D "transplantable" scaffolds with enhanced neurotrophic behaviors. Thus, the insights from this study have fundamental and translational impacts for neural-stem-cell-based regenerative medicine. PMID:24914828

Cherry, Jocie F; Bennett, Neal K; Schachner, Melitta; Moghe, Prabhas V

2014-10-01

39

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

40

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

41

The kinase domains of obscurin interact with intercellular adhesion proteins.  

PubMed

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

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

2013-05-01

42

Wettability and adhesion of marine and related adhesive proteins  

Microsoft Academic Search

Wettability on substrates with low and high surface energies of synthetic marine and related adhesive proteins has been investigated to evaluate the role of individual amino acids together with their sequences in marine adhesive proteins. The surface chemical analyses suggest that marine adhesives have a meaningful primary structure adhering to substrates. The polysaccharide chitosan adhered faster than marine adhesive proteins

Hiroyuki Yamamoto; Ayako Nishida; Kousaku Ohkawa

1999-01-01

43

The kinase domains of obscurin interact with intercellular adhesion proteins  

PubMed Central

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

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

2013-01-01

44

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

45

Bulk adhesive strength of recombinant hybrid mussel adhesive protein  

Microsoft Academic Search

Mussel adhesive proteins (MAPs) have received increased attention as potential biomedical and environmental friendly adhesives. However, practical application of MAPs has been severely limited by uneconomical extraction and unsuccessful genetic production. Developing new adhesives requires access to large quantities of material and demonstrations of bulk mechanical properties. Previously, the authors designed fp-151, a fusion protein comprised of six MAP type

Hyung Joon Cha; Dong Soo Hwang; Seonghye Lim; James D. White; Cristina R. Matos-Perez; Jonathan J. Wilker

2009-01-01

46

The adhesive properties of coacervated recombinant hybrid mussel adhesive proteins  

Microsoft Academic Search

Marine mussels attach to substrates using adhesive proteins. It has been suggested that complex coacervation (liquid–liquid phase separation via concentration) might be involved in the highly condensed and non-water dispersed adhesion process of mussel adhesive proteins (MAPs). However, as purified natural MAPs are difficult to obtain, it has not been possible to experimentally validate the coacervation model. In the present

Seonghye Lim; Yoo Seong Choi; Dong Gyun Kang; Young Hoon Song; Hyung Joon Cha

2010-01-01

47

Linking molecular affinity and cellular specificity in cadherin-mediated adhesion  

E-print Network

Linking molecular affinity and cellular specificity in cadherin-mediated adhesion P. Katsambaa,b,1 the dimerization affinities of N-cadherin and E-cadherin. These proteins are similar in sequence and struc- ture-cadherin is found to form homodimers with higher affinity than does E-cadherin and, unexpectedly, the N/E- cadherin

Ben-Shaul, Avinoam

48

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

49

N-cadherin and keratinocyte growth factor receptor mediate the functional interplay between Ki-RASG12V and p53V143A in promoting pancreatic cell migration, invasion, and tissue architecture disruption.  

PubMed

The genetic basis of pancreatic ductal adenocarcinoma, which constitutes the most common type of pancreatic malignancy, involves the sequential activation of oncogenes and inactivation of tumor suppressor genes. Among the pivotal genetic alterations are Ki-RAS oncogene activation and p53 tumor suppressor gene inactivation. We explain that the combination of these genetic events facilitates pancreatic carcinogenesis as revealed in novel three-dimensional cell (spheroid cyst) culture and in vivo subcutaneous and orthotopic xenotransplantation models. N-cadherin, a member of the classic cadherins important in the regulation of cell-cell adhesion, is induced in the presence of Ki-RAS mutation but subsequently downregulated with the acquisition of p53 mutation as revealed by gene microarrays and corroborated by reverse transcription-PCR and Western blotting. N-cadherin modulates the capacity of pancreatic ductal cells to migrate and invade, in part via complex formation with keratinocyte growth factor receptor and neural cell adhesion molecule and in part via interaction with p120-catenin. However, modulation of these complexes by Ki-RAS and p53 leads to enhanced cell migration and invasion. This preferentially induces the downstream effector AKT over mitogen-activated protein kinase to execute changes in cellular behavior. Thus, we are able to define molecules that in part are directly affected by Ki-RAS and p53 during pancreatic ductal carcinogenesis, and this provides a platform for potential new molecularly based therapeutic interventions. PMID:16705170

Deramaudt, Therese B; Takaoka, Munenori; Upadhyay, Rabi; Bowser, Mark J; Porter, Jess; Lee, Amy; Rhoades, Ben; Johnstone, Cameron N; Weissleder, Ralph; Hingorani, Sunil R; Mahmood, Umar; Rustgi, Anil K

2006-06-01

50

Characterization of sequential N-cadherin cleavage by ADAM10 and PS1  

Microsoft Academic Search

N-cadherin is essential for excitatory synaptic contact in the hippocampus. At the sites of synaptic contact, it forms a complex with Presenilin 1(PS1) and ?-catenin. N-cadherin is cleaved by ADAM10 in response to NMDA receptor stimulation, producing a membrane fragment Ncad\\/CTF1 in neurons. NMDA receptor stimulation also enhances PS1\\/?-secretase-mediated cleavage of N-cadherin. To characterize the regulatory mechanisms of the ADAM10

Kengo Uemura; Takeshi Kihara; Akira Kuzuya; Katsuya Okawa; Takaaki Nishimoto; Haruaki Ninomiya; Hachiro Sugimoto; Ayae Kinoshita; Shun Shimohama

2006-01-01

51

Adhesion and Wettability of Marine Adhesive Proteins in Aqueous Systems  

Microsoft Academic Search

The work of adhesion on substrates with low and high surface energies using a variety of homo, random and sequential polypeptides containing L-lysine has been investigated to evaluate the role of individual amino acids together with the sequences in marine adhesive proteins. The work of adhesion of poly (L-lysine) was lower (34–79 mJ\\/m) on the surfaces of Teflon and polyethylene

Hiroyuki Yamamoto; Takahiro Ogawa; Shin-Ichi Ohara; Ayako Nishida; Yuuki Hirata; Hideki Tatehata; Kousaku Ohkawa

1996-01-01

52

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

53

Microenvironmental protection of CML stem and progenitor cells from tyrosine kinase inhibitors through N-cadherin and Wnt–?-catenin signaling  

PubMed Central

Tyrosine kinase inhibitors (TKIs) are highly effective in treatment of chronic myeloid leukemia (CML) but do not eliminate leukemia stem cells (LSCs), which remain a potential source of relapse. TKI treatment effectively inhibits BCR-ABL kinase activity in CML LSCs, suggesting that additional kinase-independent mechanisms contribute to LSC preservation. We investigated whether signals from the bone marrow (BM) microenvironment protect CML LSCs from TKI treatment. Coculture with human BM mesenchymal stromal cells (MSCs) significantly inhibited apoptosis and preserved CML stem/progenitor cells following TKI exposure, maintaining colony-forming ability and engraftment potential in immunodeficient mice. We found that the N-cadherin receptor plays an important role in MSC-mediated protection of CML progenitors from TKI. N-cadherin–mediated adhesion to MSCs was associated with increased cytoplasmic N-cadherin–?-catenin complex formation as well as enhanced ?-catenin nuclear translocation and transcriptional activity. Increased exogenous Wnt-mediated ?-catenin signaling played an important role in MSC-mediated protection of CML progenitors from TKI treatment. Our results reveal a close interplay between N-cadherin and the Wnt–?-catenin pathway in protecting CML LSCs during TKI treatment. Importantly, these results reveal novel mechanisms of resistance of CML LSCs to TKI treatment and suggest new targets for treatment designed to eradicate residual LSCs in CML patients. PMID:23299311

Zhang, Bin; Li, Min; McDonald, Tinisha; Holyoake, Tessa L.; Moon, Randall T.; Campana, Dario; Shultz, Leonard

2013-01-01

54

Effects of p,p'-DDE on the mRNA and protein expressions of vimentin, N-cadherin and FSHR in rats testes: an in vivo and in vitro study.  

PubMed

To elucidate the mechanism underlying the testicular effects of 1,1-dichloro-2,2bis(p-chlorophenyl)ethylene (p,p'-DDE), the expressions of vimentin, neural cadherin and follicle-stimulating hormone receptor mRNA and proteins were measured in vivo and in vitro. Sprague-Dawley rats were dosed with p,p'-DDE at 0, 20, 60 and 100 mg/kg every other day by intraperitoneal injection for 10 days, and Sertoli cells were treated with p,p'-DDE (0, 10, 30, and 50 ?M) for 24 h. Results indicated that the survival rate of Sertoli cells was decreased with increasing doses of p,p'-DDE. In vitro and in vivo studies, p,p'-DDE could increase the expression of neural cadherin, follicle-stimulating hormone receptor mRNA, while decrease the levels of vimentin, neural cadherin and follicle-stimulating hormone receptor proteins. Moreover, immunohistochemistry analysis revealed that the protein expressions of vimentin, neural cadherin and follicle-stimulating hormone receptor in pubertal rat testes were disrupted by treatment with p,p'-DDE. Taken together, these results suggested that p,p'-DDE exposure could induce testicular toxicity through the changes of the mRNA and protein expressions of vimentin, neural cadherin and follicle-stimulating hormone receptor in vitro and in vivo. PMID:23501609

Yan, Maosheng; Shi, Yuqin; Wang, Yuping; Wang, Can; Zhou, Jun; Quan, Chao; Liu, Changjiang; Yang, Kedi

2013-05-01

55

Differential expression of E-cadherin, N-cadherin and beta-catenin in proximal and distal segments of the rat nephron.  

PubMed Central

Background The classical cadherins such as E- and N-cadherin are Ca2+-dependent cell adhesion molecules that play important roles in the development and maintenance of renal epithelial polarity. Recent studies have shown that a variety of cadherins are present in the kidney and are differentially expressed in various segments of the nephron. However, the interpretation of these findings has been complicated by the fact that the various studies focused on different panels of cadherins and utilized different species. Moreover, since only a few of the previous studies focused on the rat, information regarding the expression and localization of renal cadherins in this important species is lacking. In the present study, we have employed dual immunofluorescent labeling procedures that utilized specific antibodies against either E- or N-cadherin, along with antibodies that target markers for specific nephron segments, to characterize the patterns of cadherin expression in frozen sections of adult rat kidney. Results The results showed that N-cadherin is the predominant cadherin in the proximal tubule, but is essentially absent in other nephron segments. By contrast, E-cadherin is abundant in the distal tubule, collecting duct and most medullary segments, but is present only at very low levels in the proximal tubule. Additional results revealed different patterns of N-cadherin labeling along various segments of the proximal tubule. The S1 and S2 segments exhibit a fine threadlike pattern of labeling at the apical cell surface, whereas the S3 segment show intense labeling at the lateral cell-cell contacts. Conclusions These results indicate that E- and N-cadherin are differentially expressed in the proximal and distal tubules of rat kidney and they raise the possibility that differences in cadherin expression and localization may contribute to the differences in the susceptibility of various nephron segments to renal pathology or nephrotoxic injury. PMID:15147582

Prozialeck, Walter C; Lamar, Peter C; Appelt, Denah M

2004-01-01

56

Sulfated polysaccharide isolated from the sea cucumber Stichopus japonicus promotes neurosphere migration and differentiation via up-regulation of N-cadherin.  

PubMed

In this report, the sulfated polysaccharide (SJP) from the body wall of the sea cucumber Stichopus japonicas was extracted and tested for its capacity to affect migration and differentiation of neural stem/progenitor cells. SJP is an intensely sulfated polysaccharide with a molecular weight of 1.79 × 10(5) Da that is capable of promoting neurosphere attachment and migration in a dose-dependent manner. Moreover, SJP effectively maintains cell viability even after being deprived of mitogens. Our current results demonstrate that neurosphere are differentiated into neuronal and glial cells when exposed to SJP. These effects were accompanied by an up-regulation of the adhesion molecule, N-cadherin. In addition, we observed that blocking of PI3K activity inhibited N-cadherin-mediated activity. This SJP-induced up-regulation of N-cadherin mediates neurosphere adhesion migration and differentiation via the PI3K/Akt signaling pathway. These results suggest that SJP could be used as a therapeutic agent to mobilize neuroblast migration under conditions of brain injury and disease. PMID:22109513

Sheng, Xiehuang; Li, Min; Song, Shuliang; Zhang, Nannan; Wang, Yunshan; Liang, Hao; Wang, Weili; Ji, Aiguo

2012-04-01

57

The Beneficial Effect of Chitooligosaccharides on Cell Behavior and Function of Primary Schwann Cells is Accompanied by Up-Regulation of Adhesion Proteins and Neurotrophins.  

PubMed

Chitosan-based tissue engineered nerve grafts are successfully used for bridging peripheral nerve gaps. The biodegradation products of chitosan are water-dissolvable chitooligosaccharides (COSs), which have been shown to support peripheral nerve regeneration. In this study, we aimed to examine in vitro interactions between COSs and Schwann cells (SCs), the principal glial cells in the peripheral nervous system. Treatment of primary SCs with COSs enhanced cell survival and promoted cell proliferation in a dose-dependent manner (0.25-1.0 mg/ml), as determined by real-time cell analyzer-based assay, cell growth assay, cell cycle analysis, and EdU incorporation. Western blot analysis and immunocytochemistry with antibodies against MBP and MAG (two myelin-specific markers) showed that COSs enhanced axonal myelination in a co-culture system consisting of SCs and dorsal root ganglia (DRGs). Furthermore, we observed that COSs enhanced the protein expression of N-cadherin and ?-catenin in primary SCs, and also increased the release of BDNF and NGF in co-culture of SCs with DRGs. And we also noted that knockdown of N-cadherin in primary SCs reduced COSs-induced increase in cell proliferation. Our findings suggested that beneficial effects of COSs on cell behavior and functions of primary SCs might be accompanied by up-regulation of adhesion proteins and neurotrophins, thus providing a new insight into the supportive role of COSs during peripheral nerve regeneration. PMID:25119164

Jiang, Maorong; Cheng, Qiong; Su, Wenfeng; Wang, Caiping; Yang, Yuming; Cao, Zheng; Ding, Fei

2014-11-01

58

A self-renewing division of zebrafish Müller glial cells generates neuronal progenitors that require N-cadherin to regenerate retinal neurons.  

PubMed

Müller glia function as retinal stem cells in adult zebrafish. In response to loss of retinal neurons, Müller glia partially dedifferentiate, re-express neuroepithelial markers and re-enter the cell cycle. We show that the immunoglobulin superfamily adhesion molecule Alcama is a novel marker of multipotent retinal stem cells, including injury-induced Müller glia, and that each Müller glial cell divides asymmetrically only once to produce an Alcama-negative, proliferating retinal progenitor. The initial mitotic division of Müller glia involves interkinetic nuclear migration, but mitosis of retinal progenitors occurs in situ. Rapidly dividing retinal progenitors form neurogenic clusters tightly associated with Alcama/N-cadherin-labeled Müller glial radial processes. Genetic suppression of N-cadherin function interferes with basal migration of retinal progenitors and subsequent regeneration of HuC/D(+) inner retinal neurons. PMID:24154521

Nagashima, Mikiko; Barthel, Linda K; Raymond, Pamela A

2013-11-01

59

ADAM-10 could mediate cleavage of N-cadherin promoting apoptosis in human atherosclerotic lesions leading to vulnerable plaque: a morphological and immunohistochemical study.  

PubMed

Atherosclerosis remains a major cause of mortality. Whereas the histopathological progression of atherosclerotic lesions is well documented, much less is known about the development of unstable or vulnerable plaque, which can rupture leading to thrombus, luminal occlusion and infarct. Apoptosis in the fibrous cap, which is rich in vascular smooth muscle cells (VSMCs) and macrophages, and its subsequent weakening or erosion seems to be an important regulator of plaque stability. The aim of our study was to improve our knowledge on the biological mechanisms that cause plaque instability in order to develop new therapies to maintain atherosclerotic plaque stability and avoid its rupture. In our study, we collected surgical specimens from atherosclerotic plaques in the right or left internal carotid artery of 62 patients with evident clinical symptoms. Histopathology and histochemistry were performed on wax-embedded sections. Immunohistochemical localization of caspase-3, N-cadherin and ADAM-10 was undertaken in order to highlight links between apoptosis, as expressed by caspase-3 immunostaining, and possible roles of N-cadherin, a cell-cell junction protein in VSMCs and macrophages that provides a pro-survival signal reducing apoptosis, and ADAM-10, a "disintegrin and metalloproteases" that is able to cleave N-cadherin in glioblastomas. Our results showed that when apoptosis, expressed by caspase-3 immunostaining, increased in the fibrous cap, rich in VSMCs and macrophages, the expression of N-cadherin decreased. The decreased N-cadherin expression, in turn, was linked to increased ADAM-10 expression. This study shows that apoptotic events are probably involved in the vulnerability of atherosclerotic plaque. PMID:24985126

Musumeci, Giuseppe; Coleman, Raymond; Imbesi, Rosa; Magro, Gaetano; Parenti, Rosalba; Szychlinska, Marta Anna; Scuderi, Rosario; Cinà, Claudio Salvatore; Castorina, Sergio; Castrogiovanni, Paola

2014-09-01

60

Intervention Effects of Ganoderma Lucidum Spores on Epileptiform Discharge Hippocampal Neurons and Expression of Neurotrophin-4 and N-Cadherin  

PubMed Central

Epilepsy can cause cerebral transient dysfunctions. Ganoderma lucidum spores (GLS), a traditional Chinese medicinal herb, has shown some antiepileptic effects in our previous studies. This was the first study of the effects of GLS on cultured primary hippocampal neurons, treated with Mg2+ free medium. This in vitro model of epileptiform discharge hippocampal neurons allowed us to investigate the anti-epileptic effects and mechanism of GLS activity. Primary hippocampal neurons from <1 day old rats were cultured and their morphologies observed under fluorescence microscope. Neurons were confirmed by immunofluorescent staining of neuron specific enolase (NSE). Sterile method for GLS generation was investigated and serial dilutions of GLS were used to test the maximum non-toxic concentration of GLS on hippocampal neurons. The optimized concentration of GLS of 0.122 mg/ml was identified and used for subsequent analysis. Using the in vitro model, hippocampal neurons were divided into 4 groups for subsequent treatment i) control, ii) model (incubated with Mg2+ free medium for 3 hours), iii) GLS group I (incubated with Mg2+ free medium containing GLS for 3 hours and replaced with normal medium and incubated for 6 hours) and iv) GLS group II (neurons incubated with Mg2+ free medium for 3 hours then replaced with a normal medium containing GLS for 6 hours). Neurotrophin-4 and N-Cadherin protein expression were detected using Western blot. The results showed that the number of normal hippocampal neurons increased and the morphologies of hippocampal neurons were well preserved after GLS treatment. Furthermore, the expression of neurotrophin-4 was significantly increased while the expression of N-Cadherin was decreased in the GLS treated group compared with the model group. This data indicates that GLS may protect hippocampal neurons by promoting neurotrophin-4 expression and inhibiting N-Cadherin expression. PMID:23637882

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

2013-01-01

61

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

PubMed

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

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

2013-01-01

62

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; Munoz-Antonia, Teresita; Cress, W. Douglas

2014-01-01

63

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

64

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

65

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

66

Wettability and Adhesion of Synthetic Marine Adhesive Proteins and Related Model Compounds  

Microsoft Academic Search

Wettability on substrates with low and high surface energies using synthetic marine adhesive proteins and related model compounds containing Lys has been investigated to evaluate the role of individual amino acids together with the sequences in marine adhesive proteins. Among sequential polypeptides, those containing Gly and Lys exhibited higher work of adhesion in four different substrates. The important role of

HIROYUKI YAMAMOTO; TAKAHIRO OGAWA; KOUSAKU OHKAWA

1995-01-01

67

Biomimetic Adhesive Polymers Based on Mussel Adhesive Proteins  

Microsoft Academic Search

Nature provides many outstanding examples of adhesive strategies from which chemists and material scientists can draw inspiration in their pursuit of new adhesive materials. As described in other chapters of this book, detailed studies of the adhesive mechanisms of geckos, mussels and other organisms during the past several decades have enhanced our understanding of the underlying physicochemical principles to the

BRUCE P. LEE; JEFFREY L. DALSIN; PHILLIP B. MESSERSMITH

68

Apoprotein(a) is an Adhesive Protein  

Microsoft Academic Search

In preceding publications we have shown that apoprotein(a) (apo(a)) has important beneficial physiological properties that by far outweigh its disadvantages. We have also identified powerful beneficial properties of apo(a) in the defense against the proliferation of various diseases. Here we extend this concept and propose that apo(a) plays a decisive physiological role as an adhesive protein. Apo(a) contains an arginine-

Matthias Rath; Linus Pauling

69

Cell Adhesion to Unnatural Ligands Mediated by a Bifunctional Protein  

E-print Network

Cell Adhesion to Unnatural Ligands Mediated by a Bifunctional Protein Juan Sa@uchicago.edu Abstract: This paper describes a molecular strategy to restore adhesion of cells to surfaces that otherwise to cell-surface integrin adhesion receptors. In this way, the fusion protein can bind to a monolayer

Mrksich, Milan

70

Soy Protein Adhesive Blends with Synthetic Latex on Wood Veneer  

Microsoft Academic Search

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

Guangyan Qi; Xiuzhi Susan Sun

2011-01-01

71

Tissue adhesive using synthetic model adhesive proteins inspired by the marine mussel  

Microsoft Academic Search

The surface free energy and its dispersion and polar components of pigskin were determined by wettability measurements. The contact angles and work of adhesion of solutions of the synthetic model adhesive sequence poly(Gly-Tyr-Lys) inspired by marine adhesive proteins were measured on the epidermis and the dermis of pigskin. Also the surface free energy of pigskin was determined using contact angles

H. Tatehata; A. Mochizuki; K. Ohkawa; M. Yamada; H. Yamamoto

2001-01-01

72

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  

Microsoft Academic Search

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,

Wen-bin Liu; Zhi-hong Cui; Lin Ao; Zi-yuan Zhou; Yan-hong Zhou; Xiao-yan Yuan; Yun-long Xiang; Jin-yi Liu; Jia Cao

2011-01-01

73

Role of N-Cadherin cis and trans Interfaces in the Dynamics of Adherens Junctions in Living Cells  

PubMed Central

Cadherins, Ca2+-dependent adhesion molecules, are crucial for cell-cell junctions and remodeling. Cadherins form inter-junctional lattices by the formation of both cis and trans dimers. Here, we directly visualize and quantify the spatiotemporal dynamics of wild-type and dimer mutant N-cadherin interactions using time-lapse imaging of junction assembly, disassembly and a FRET reporter to assess Ca2+-dependent interactions. A trans dimer mutant (W2A) and a cis mutant (V81D/V174D) exhibited an increased Ca2+-sensitivity for the disassembly of trans dimers compared to the WT, while another mutant (R14E) was insensitive to Ca2+-chelation. Time-lapse imaging of junction assembly and disassembly, monitored in 2D and 3D (using cellular spheroids), revealed kinetic differences in the different mutants as well as different behaviors in the 2D and 3D environment. Taken together, these data provide new insights into the role that the cis and trans dimers play in the dynamic interactions of cadherins. PMID:24312555

Junek, Stephan; Vogel, Dirk; Ansari, Nariman; Stelzer, Ernst H. K.; Schuman, Erin

2013-01-01

74

Laser processing of natural mussel adhesive protein thin films  

Microsoft Academic Search

A novel laser processing technique is presented for depositing mussel adhesive protein thin films. Synthetic adhesives (e.g., acrylics, cyanoacrylates, epoxies, phenolics, polyurethanes, and silicones) have largely displaced natural adhesives in the automotive, aerospace, biomedical, electronic, and marine equipment industries over the past century. However, rising concerns over the environmental and health effects of solvents, monomers, and additives used in synthetic

A. Doraiswamy; R. J. Narayan; R. Cristescu; I. N. Mihailescu; D. B. Chrisey

2007-01-01

75

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

76

Adhesion Proteins, Stem Cells, and Arrhythmogenesis  

PubMed Central

Cell-transplantation therapy is a promising treatment option that is being actively explored as a way to repair cardiac muscle. The ultimate goal is to reconstitute the architecture of the cardiac muscle and to reestablish electrical propagation, while avoiding hypertrophy and scar formation. In this review, we focus on recent advances in the field as well as the difficulties encountered when the engraftment of cells into the host tissue is to be confirmed and functionally characterized. This is critical since incomplete or partial engraftment of transplanted cells within the host cardiac network exacerbates the heterogeneity already present in the injured myocardium and increases its propensity to arrhythmia. We conclude with a brief discussion of how the modulation of cell adhesion via modification of coupling proteins within transplanted cells may facilitate engraftment and alleviate the arrhythmogenic potential of cardiac grafts. PMID:18176845

Gillum, Nikki

2010-01-01

77

ADAM9 Up-Regulates N-Cadherin via miR-218 Suppression in Lung Adenocarcinoma Cells  

PubMed Central

Lung cancer is the leading cause of cancer death worldwide, and brain metastasis is a major cause of morbidity and mortality in lung cancer. CDH2 (N-cadherin, a mesenchymal marker of the epithelial-mesenchymal transition) and ADAM9 (a type I transmembrane protein) are related to lung cancer brain metastasis; however, it is unclear how they interact to mediate this metastasis. Because microRNAs regulate many biological functions and disease processes (e.g., cancer) by down-regulating their target genes, microRNA microarrays were used to identify ADAM9-regulated miRNAs that target CDH2 in aggressive lung cancer cells. Luciferase assays and western blot analysis showed that CDH2 is a target gene of miR-218. MiR-218 was generated from pri-mir-218-1, which is located in SLIT2, in non-invasive lung adenocarcinoma cells, whereas its expression was inhibited in aggressive lung adenocarcinoma. The down-regulation of ADAM9 up-regulated SLIT2 and miR-218, thus down-regulating CDH2 expression. This study revealed that ADAM9 activates CDH2 through the release of miR-218 inhibition on CDH2 in lung adenocarcinoma. PMID:24705471

Sher, Yuh-Pyng; Wang, Li-Ju; Chuang, Li-Ling; Tsai, Mong-Hsun; Kuo, Ting-Ting; Huang, Cheng-Chung; Chuang, Eric Y.; Lai, Liang-Chuan

2014-01-01

78

MODULATION OF N-CADHERIN JUNCTIONS AND THEIR ROLE AS EPICENTERS OF DIFFERENTIATION-SPECIFIC ACTIN REGULATION IN THE DEVELOPING LENS  

PubMed Central

Extensive elongation of lens fiber cells is a central feature of lens morphogenesis. Our study investigates the role of N-cadherin junctions in this process in vivo. We investigate both the molecular players involved in N-cadherin junctional maturation and the subsequent function of these junctions as epicenters for the assembly of an actin cytoskeleton that drives morphogenesis. We present the first evidence of nascent cadherin junctions in vivo, and show they are a prominent feature along lateral interfaces of undifferentiated lens epithelial cells. Maturation of these N-cadherin junctions, required for lens cell differentiation, preceded organization of a cortical actin cytoskeleton along the cells’ lateral borders, but was linked to recruitment of ?-catenin and dephosphorylation of N-cadherin-linked ?-catenin. Biochemical analysis revealed differentiation-specific recruitment of actin regulators cortactin and Arp3 to maturing N-cadherin junctions of differentiating cells, linking N-cadherin junctional maturation with actin cytoskeletal assembly during fiber cell elongation. Blocking formation of mature N-cadherin junctions led to reduced association of ?-catenin with N-cadherin, prevented organization of actin along lateral borders of differentiating lens fiber cells and blocked their elongation. These studies provide a molecular link between N-cadherin junctions and the organization of an actin cytoskeleton that governs lens fiber cell morphogenesis in vivo. PMID:20969840

Leonard, Michelle; Zhang, Liping; Zhai, Ni; Cader, Ahmad; Chan, Yim; Nowak, Roberta B.; Fowler, Velia M.; Menko, A. Sue

2010-01-01

79

Shear strength and water resistance of modified soy protein adhesives  

Microsoft Academic Search

Soy protein polymers recently have been considered as alternatives to petroleum polymers to ease environmental pollution.\\u000a The use of soy proteins as adhesives for plywood has been limited because of their low water resistance. The objective of\\u000a this research was to test the water resistance of adhesives containing modified soy proteins in walnut, maple, poplar, and\\u000a pine plywood applications. Gluing

Xiuzhi Sun; Ke Bian

1999-01-01

80

Thrombin induces slug-mediated E-cadherin transcriptional repression and the parallel up-regulation of N-cadherin by a transcription-independent mechanism in RPE cells.  

PubMed

The proliferation, directional migration to the vitreous and epithelial-mesenchymal transition (EMT) of quiescent, differentiated retinal pigment epithelium (RPE) cells is a major feature in the development of proliferative vitreoretinopathy (PVR) following exposure of the immuno-privileged eye niche to serum components, thrombin among them. We have previously documented thrombin induction of RPE cell proliferation and migration. We here analyzed the effect of thrombin on the E/N cadherin switch, a hallmark of EMT. Results show that thrombin induces the specific repression of epithelial E-cadherin gene transcription, alongside with the up-regulation of mesenchymal N-cadherin protein in RPE cells. We demonstrate, for the first time, that thrombin induces E-cadherin repression by stimulating snail-2 (SLUG) transcription factor expression, and the concomitant up-regulation of N-cadherin through the transcription-independent increase in protein translation promoted by PI3K/PKC-?/mTOR signaling. Our present findings suggest that the activation of protease-activated receptor-1 (PAR-1) by thrombin induces EMT of RPE cells, further supporting a central role for thrombin in PVR pathogenesis. PMID:22833386

Palma-Nicolás, José Prisco; López-Colomé, Ana María

2013-03-01

81

Cadherin 11, a miR-675 Target, Induces N-Cadherin Expression and Epithelial-Mesenchymal Transition in Melasma.  

PubMed

Cadherin 11 (CDH11) was identified as a target of miR-675 by using a luciferase reporter assay. CDH11 expression and miR-675 expression were inversely correlated. CDH11 expression was not detected in melanocytes, but CDH11 expression in fibroblasts and keratinocytes positively influenced melanogenesis via the canonical Wnt and AKT activation pathways in cocultured melanocytes. CDH11 in fibroblasts or keratinocytes induced N-cadherin and Twist1 expression, while decreasing E-cadherin expression. This suggests a role for CDH11 in epithelial-mesenchymal transition. CDH11 in fibroblasts also induced the migration of cocultured melanocytes. N-cadherin knockdown abolished the tyrosinase expression that was induced in CDH11-overexpressing fibroblasts. Collectively, our data indicate that CDH11 in fibroblasts and keratinocytes is a target of miR-675, and could be involved in melanogenesis through the induction of N-cadherin during epithelial-mesenchymal transition. PMID:24940649

Kim, Nan-Hyung; Choi, Soo-Hyun; Lee, Tae Ryong; Lee, Chang-Hoon; Lee, Ai-Young

2014-12-01

82

Soy protein isolate molecular level contributions to bulk adhesive properties  

NASA Astrophysics Data System (ADS)

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

Shera, Jeanne Norton

83

Mussel-mimetic protein-based adhesive hydrogel.  

PubMed

Hydrogel systems based on cross-linked polymeric materials which could provide both adhesion and cohesion in wet environment have been considered as a promising formulation of tissue adhesives. Inspired by marine mussel adhesion, many researchers have tried to exploit the 3,4-dihydroxyphenylalanine (DOPA) molecule as a cross-linking mediator of synthetic polymer-based hydrogels which is known to be able to achieve cohesive hardening as well as adhesive bonding with diverse surfaces. Beside DOPA residue, composition of other amino acid residues and structure of mussel adhesive proteins (MAPs) have also been considered important elements for mussel adhesion. Herein, we represent a novel protein-based hydrogel system using DOPA-containing recombinant MAP. Gelation can be achieved using both oxdiation-induced DOPA quinone-mediated covalent and Fe(3+)-mediated coordinative noncovalent cross-linking. Fe(3+)-mediated hydrogels show deformable and self-healing viscoelastic behavior in rheological analysis, which is also well-reflected in bulk adhesion strength measurement. Quinone-mediated hydrogel has higher cohesive strength and can provide sufficient gelation time for easier handling. Collectively, our newly developed MAP hydrogel can potentially be used as tissue adhesive and sealant for future applications. PMID:24650082

Kim, Bum Jin; Oh, Dongyeop X; Kim, Sangsik; Seo, Jeong Hyun; Hwang, Dong Soo; Masic, Admir; Han, Dong Keun; Cha, Hyung Joon

2014-05-12

84

Polymer adhesion at surfaces: biological adhesive proteins and their synthetic mimics  

NASA Astrophysics Data System (ADS)

Mussels are famous for their ability to permanently adhere to a wide variety of wet surfaces, such as rocks, metal and polymer ship hulls, and wood structures. They accomplish this through specialized proteins collectively referred to as mussel adhesive proteins (MAPs). The biophysical aspects of MAP adhesion is being revealed through the use of single molecule force measurements. The results provide insight into the adhesive roles of key amino acids found in these proteins, including the magnitude of adhesive forces, cooperative effects, and their self-healing properties. This molecular-level information is being incorporated into designs of biomimetic polymer coatings for a variety of applications. Our biomimetic approach to polymer design will be illustrated by a few examples where adhesive constituents found in MAPs are exploited to make wet-adhesive polymer coatings. In addition, small molecule analogs of MAPs can be used to apply thin functional films onto virtually any material surface using a facile approach. These coatings have a variety of potential uses in microelectronics, water treatment, prevention of environmental biofouling, and for control of biointerfacial phenomena at the surfaces of medical/diagnostic devices.

Messersmith, Phillip

2008-03-01

85

Emerging role for ERM proteins in cell adhesion and migration.  

PubMed

The highly related ERM (Ezrin, Radixin, Moesin) proteins provide a regulated linkage between the membrane and the underlying actin cytoskeleton. They also provide a platform for the transmission of signals in responses to extracellular cues. Studies in different model organisms and in cultured cells have highlighted the importance of ERM proteins in the generation and maintenance of specific domains of the plasma membrane. A central question is how do ERM proteins coordinate actin filament organization and membrane protein transport/stability with signal transduction pathways to build up complex structures? Through their interaction with numerous partners including membrane proteins, actin cytoskeleton and signaling molecules, ERM proteins have the ability to organize multiprotein complexes in specific cellular compartments. Likewise, ERM proteins participate in diverse functions including cell morphogenesis, endocytosis/exocytosis, adhesion and migration. This review focuses on aspects still poorly understood related to the function of ERM proteins in epithelial cell adhesion and migration. PMID:21343695

Arpin, Monique; Chirivino, Dafne; Naba, Alexandra; Zwaenepoel, Ingrid

2011-01-01

86

Vascular adhesion protein-1 blockade suppresses choroidal neovascularization  

Microsoft Academic Search

Vascular adhesion protein-1 (VAP-1) is an endothelial cell adhesion molecule involved in leu- kocyte recruitment. Leukocytes and, in particular, mac- rophages play an important role in the development of choroidal neovascularization (CNV), an integral com- ponent of age-related macular degeneration (AMD). Previously, we showed a role for VAP-1 in ocular inflammation. Here, we investigate the expression of VAP-1 in the

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

2008-01-01

87

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

E-print Network

Adhesive strength and curing rate of marine mussel protein extracts on porcine small intestinal Available online 16 April 2007 Abstract An adhesive protein extracted from marine mussels (Mytilus edulis to improve adhesive curing. Specifically, mussel adhesive protein solution (MAPS, 0.5 mM dihydroxy

Shi, Riyi

88

N-cadherin/wnt interaction controls bone marrow mesenchymal cell fate and bone mass during aging.  

PubMed

Age-related bone loss is characterized by reduced osteoblastogenesis and excessive bone marrow adipogenesis. The mechanisms governing bone marrow mesenchymal stromal cell (BMSC) differentiation into adipocytes or osteoblasts during aging are unknown. We show here that overexpressing N-cadherin (Cadh2) in osteoblasts increased BMSC adipocyte differentiation and reduced osteoblast differentiation in young transgenic (Tg) mice whereas this phenotype was fully reversed with aging. The reversed phenotype with age was associated with enhanced Wnt5a and Wnt10b expression in osteoblasts and a concomitant increase in BMSC osteogenic differentiation. Consistent with this mechanism, conditioned media from young wild type osteoblasts inhibited adipogenesis and promoted osteoblast differentiation in BMSC from old Cadh2 Tg mice, and this response was abolished by Wnt5a and Wnt10b silencing. Transplantation of BMSC from old Cadh2 Tg mice into young Tg recipients increased Wnt5a and Wnt10b expression and rescued BMSC osteogenic differentiation. In senescent osteopenic mice, blocking the CADH2-Wnt interaction using an antagonist peptide increased Wnt5a and Wnt10b expression, bone formation, and bone mass. The data indicate that Cadh2/Wnt interaction in osteoblasts regulates BMSC lineage determination, bone formation, and bone mass and suggest a therapeutic target for promoting bone formation in the aging skeleton. PMID:24664975

Haÿ, Eric; Dieudonné, François-Xavier; Saidak, Zuzana; Marty, Caroline; Brun, Julia; Da Nascimento, Sophie; Sonnet, Pascal; Marie, Pierre J

2014-11-01

89

The catenin/cadherin adhesion system is localized in synaptic junctions bordering transmitter release zones  

PubMed Central

Molecular mechanisms linking pre- and postsynaptic membranes at the interneuronal synapses are little known. We tested the cadherin adhesion system for its localization in synapses of mouse and chick brains. We found that two classes of cadherin-associated proteins, alpha N- and beta-catenin, are broadly distributed in adult brains, colocalizing with a synaptic marker, synaptophysin. At the ultrastructural level, these proteins were localized in synaptic junctions of various types, forming a symmetrical adhesion structure. These structures sharply bordered the transmitter release sites associated with synaptic vesicles, although their segregation was less clear in certain types of synapses. N-cadherin was also localized at a similar site of synaptic junctions but in restricted brain nuclei. In developing synapses, the catenin-bearing contacts dominated their junctional structures. These findings demonstrate that interneuronal synaptic junctions comprise two subdomains, transmitter release zone and catenin-based adherens junction. The catenins localized in these junctions are likely associated with certain cadherin molecules including N-cadherin, and the cadherin/ catenin complex may play a critical role in the formation or maintenance of synaptic junctions. PMID:8909549

1996-01-01

90

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

Microsoft Academic Search

Mussel adhesive proteins have been suggested as a basis for environmentally friendly adhesives for use in aqueous conditions and in medicine. However, attempts to produce functional and economical recombinant mussel adhesive proteins (mainly foot protein type 1) in several systems have failed. Here, the cDNA coding for Mytilus galloprovincialis foot protein type 5 (Mgfp-5) was isolated for the first time.

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

2004-01-01

91

Whey-protein based environmentally friendly wood adhesives  

Microsoft Academic Search

Purpose – The purpose of this paper is to develop an environmentally safe aqueous polymer-isocyanate (API) wood adhesive for structural uses with whey protein isolate (WPI) that is a by-product of cheese making. Design\\/methodology\\/approach – The API formulations with whey proteins denatured at different heating temperatures and times, WPI\\/polyvinyl alcohol (PVA) denaturing processes, PVA contents and nano-CaCO3 (as filler) contents

Zhenhua Gao; Guoping Yu; Yihong Bao; Mingruo Guo

2011-01-01

92

Halogenated DOPA in a Marine Adhesive Protein  

Microsoft Academic Search

The sandcastle worm Phragmatopoma californica, a marine polychaete, constructs a tube-like shelter by cementing together sand grains using a glue secreted from the building organ in its thorax. The glue is a mixture of post-translationally modified proteins, notably the cement proteins Pc-1 and Pc-2 with the amino acid, 3,4-dihydroxyphenyl-L-alanine (DOPA). Significant amounts of a halogenated derivative of DOPA were isolated

Cheng Jun Sun; Aasheesh Srivastava; Jack R. Reifert; J. Herbert Waite

2009-01-01

93

Vascular adhesion protein-1 blockade suppresses choroidal neovascularization  

PubMed Central

Vascular adhesion protein-1 (VAP-1) is an endothelial cell adhesion molecule involved in leukocyte recruitment. Leukocytes and, in particular, macrophages play an important role in the development of choroidal neovascularization (CNV), an integral component of age-related macular degeneration (AMD). Previously, we showed a role for VAP-1 in ocular inflammation. Here, we investigate the expression of VAP-1 in the choroid and its role in CNV development. VAP-1 was expressed in the choroid, exclusively in the vessels, and colocalized in the vessels of the CNV lesions. VAP-1 blockade with a novel and specific inhibitor significantly decreased CNV size, fluorescent angiographic leakage, and the accumulation of macrophages in the CNV lesions. Furthermore, VAP-1 blockade significantly reduced the expression of inflammation-associated molecules such as tumor necrosis factor (TNF) -?, monocyte chemoattractant protein (MCP) -1, and intercellular adhesion molecule (ICAM) -1. This work provides evidence for an important role of VAP-1 in the recruitment of macrophages to CNV lesions, establishing a novel link between VAP-1 and angiogenesis. Inhibition of VAP-1 may become a new therapeutic strategy in the treatment of AMD.—Noda, K., She, H., Nakazawa, T., Hisatomi, T., Nakao, S., Almulki, L., Zandi, S., Miyahara, S., Ito, Y., Thomas, K. L., Garland, R. C., Miller, J. W., Gragoudas, E. S., Mashima, Y., Hafezi-Moghadam, A. Vascular adhesion protein-1 blockade suppresses choroidal neovascularization. PMID:18436961

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

2008-01-01

94

Adhesive studies of synthetic polypeptides: A model for marine adhesive proteins  

Microsoft Academic Search

As a basic approach to clarify the adhesive power of marine proteins, the bonding strength (tensile and compressive shear) of a variety of synthetic polypeptides including polydecapeptide dissolved in water or organic solvents on metals (Fe and Al2O3) and rubber (Buna) has been investigated. High-molecular-weight poly(Lys) HBr was found to have the highest tensile strength of 123 kg\\/cm on Fe,

Hiroyuki Yamamoto

1987-01-01

95

Protein Adsorption and Subsequent Fibroblasts Adhesion on Hydroxyapatite Nanocrystals  

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

96

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

97

Adhesion  

MedlinePLUS

... as the shoulder Eyes Inside the abdomen or pelvis Adhesions can become larger or tighter over time. ... Other causes of adhesions in the abdomen or pelvis include: Appendicitis , most often when the appendix breaks ...

98

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 GENUNCIO; DE SIQUEIRA SILVA, ANDREZA CRISTINA; MORAES, KAREN C.M.

2014-01-01

99

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

Microsoft Academic Search

The neural cadherin (N-cadherin) is a Ca 2+- dependent cell-cell adhesion molecule detected in neu- ral tissues as well as in non-neural tissues. We report here the nucleotide sequence of the chicken N-cad- herin cDNA and the deduced amino acid sequence. The sequence data suggest that N-cadherin has one transmembrane domain which divides the molecule into an extracellular and a

Kohei Hatta; Akinao Nose; Akira Nagafuchi; Masatoshi Takeichi

1988-01-01

100

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

PubMed Central

Focal adhesion (FA) signaling mediated by adhesion to extracellular matrix and growth factor receptors contributes to the regulation of the cellular stress response to external stimuli. Critical to focal adhesion assembly and signaling is the adapter protein PINCH1. To evaluate whether the prosurvival function of PINCH1 in radiation cell survival depends on cell adhesion, we examined PINCH1fl/fl and PINCH1?/? mouse embryonic fibroblasts and human cancer cell lines. Here, we found that the enhanced cellular radiosensitivity mediated by PINCH1 depletion observed under adhesion conditions is conserved when cells are irradiated under suspension conditions. This unsuspected finding could not be explained by the observed modification of adhesion and growth factor associated signaling involving FAK, Paxillin, p130CAS, Src, AKT, GSK3? and ERK1/2 under suspension and serum withdrawal relative to adhesion conditions with serum. Our data suggest that the adapter protein PINCH1 critically participates in the regulation of the cellular radiosensitivity of normal and malignant cells similarly under adhesion and suspension conditions. PMID:20927395

Sandfort, Veit; Eke, Iris; Cordes, Nils

2010-01-01

101

Small heat shock proteins in cellular adhesion and migration  

PubMed Central

Cellular locomotion and adhesion critically depend on regulated turnover of filamentous actin. Biochemical data from diverse model systems support a role for the family of small heat shock proteins (HSPBs) in microfilament regulation. The small chaperones could either act directly, through competition with the motor myosin, or indirectly, through modulation of actin depolymerizing factor/cofilin activity. However, a direct link between HSPBs and actin-based cellular motility remained to be established. In a recent experimental genetics study, we provided evidence for regulation of Plasmodium motility by HSPB6/Hsp20. The infectious forms of malaria parasites, termed sporozoites, display fast and continuous substrate-dependent motility, which is largely driven by turnover of actin microfilaments. Sporozoite gliding locomotion is essential to avoid destruction by host defense mechanisms and to ultimately reach a hepatocyte, the target cell, where to transform and replicate. Genetic ablation of Plasmodium HSP20 dramatically changed sporozoite speed and substrate adhesion, resulting in impaired natural malaria transmission. In this article, we discuss the function of Hsp20 in this fast-moving unicellular protozoan and implications for the roles of HSPBs in adhesion and migration of eukaryotic cells. PMID:22568951

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

2012-01-01

102

Self-Assembled Monolayers That Resist the Adsorption of Proteins and the Adhesion of Bacterial and Mammalian  

E-print Network

to the adhesion of bacteria (Staphylococcus aureus, Staphylococcus epidermidis) and the attachment and spreading of proteins from solution and the adhesion of Staphylococcus epidermidis, Staphylococcus aureus, and bovine

Prentiss, Mara

103

Adhesion and structure properties of protein nanomaterials containing hydrophobic and charged amino acids.  

PubMed

Protein polymers are being used or considered for biobased adhesives and coating materials. Most adhesives derived from macro protein molecules work through receptors or cross-links to bring about adhesion. The adhesion mechanism of protein polymers would lead to better understanding of adhesives and the discovery of new practical properties of protein polymers at both nano- and macro-scales. The objective of this research work was to study adhesion properties of protein polymers at nanoscale (a peptide adhesive with nanometer-scale units that range in size of several nanometers, defined as protein nanomaterial). Seven protein nanomaterial samples with different degrees of adhesive strength were designed and synthesized using solid phase chemistries. All protein nanomaterials contain a common hydrophobic core flanked by charged amino acid sequences. The adhesion properties of the protein nanomaterials were investigated at different pH values and curing temperatures. The protein nanomaterials self aggregate and interact with the wood surface. The protein nanomaterial KKK-FLIVIGSII-KKK identified in this study had high adhesive strength toward wood. It had the highest shear strength at pH 12, with an amino acid sequence that was very hydrophobic and uncharged. This protein nanomaterial underwent structural analyses using circular dichroism, laser-Fourier transform infrared, and laser desorption mass spectrometry. At pH 12 this peptide adopted a pH-induced beta-like conformation. Adhesive strength reflects contributions of both hydrogen bonding and van der Waals interactions. Ionic and covalent bonds do not appear to be significant factors for adhesion in this study. PMID:16573147

Shen, Xinchun; Mo, Xiaoqun; Moore, Robyn; Frazier, Shawnalea J; Iwamoto, Takeo; Tomich, John M; Sun, Xiuzhi Susan

2006-03-01

104

Galectins: matricellular glycan-binding proteins linking cell adhesion, migration, and survival  

Microsoft Academic Search

.  Galectins are a taxonomically widespread family of glycan-binding proteins, defined by at least one conserved carbohydrate-recognition\\u000a domain with a canonical amino acid sequence and affinity for ?-galactosides. Because of their anti-adhesive as well as pro-adhesive\\u000a extracellular functions, galectins appear to be a novel class of adhesion-modulating proteins collectively known as matricellular\\u000a proteins (which include thrombospondin, SPARC, tenascin, hevin, and disintegrins).

M. T. Elola; C. Wolfenstein-Todel; M. F. Troncoso; G. R. Vasta; G. A. Rabinovich

2007-01-01

105

Protein Engineering vol.11 no.6 pp.415420, 1998 Electrotactins: a class of adhesion proteins with conserved  

E-print Network

to the active site of acetylcholinesterase, and in the analogous zone for the ChE-like domain of the adhesion of adhesion proteins which we have named `electrotactins'. Keywords: acetylcholinesterase/cell adhesionEs. Cholinesterases are a family of enzymes which fall broadly into two types, acetylcholinesterase (AChE) and butyryl

Sussman, Joel L.

106

Focal adhesion protein abnormalities in myelodysplastic mesenchymal stromal cells  

SciTech Connect

Direct cell-cell contact between haematopoietic progenitor cells (HPCs) and their cellular microenvironment is essential to maintain 'stemness'. In cancer biology, focal adhesion (FA) proteins are involved in survival signal transduction in a wide variety of human tumours. To define the role of FA proteins in the haematopoietic microenvironment of myelodysplastic syndromes (MDS), CD73-positive mesenchymal stromal cells (MSCs) were immunostained for paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and p130CAS, and analysed for reactivity, intensity and cellular localisation. Immunofluorescence microscopy allowed us to identify qualitative and quantitative differences, and subcellular localisation analysis revealed that in pathological MSCs, paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} formed nuclear molecular complexes. Increased expression of paxillin, pFAK [Y{sup 397}], and HSP90{alpha}/{beta} and enhanced nuclear co-localisation of these proteins correlated with a consistent proliferative advantage in MSCs from patients with refractory anaemia with excess blasts (RAEB) and negatively impacted clonogenicity of HPCs. These results suggest that signalling via FA proteins could be implicated in HPC-MSC interactions. Further, because FAK is an HSP90{alpha}/{beta} client protein, these results suggest the utility of HSP90{alpha}/{beta} inhibition as a target for adjuvant therapy for myelodysplasia.

Aanei, Carmen Mariana, E-mail: caanei@yahoo.com [Laboratoire Hematologie, CHU de Saint-Etienne, 42055, Saint-Etienne (France); Department of Immunology, Gr. T. Popa University of Medicine and Pharmacy, 700115, Iasi (Romania); Eloae, Florin Zugun [Department of Immunology, Gr. T. Popa University of Medicine and Pharmacy, 700115, Iasi (Romania)] [Department of Immunology, Gr. T. Popa University of Medicine and Pharmacy, 700115, Iasi (Romania); Flandrin-Gresta, Pascale [Laboratoire Hematologie, CHU de Saint-Etienne, 42055, Saint-Etienne (France) [Laboratoire Hematologie, CHU de Saint-Etienne, 42055, Saint-Etienne (France); CNRS UMR 5239, Universite de Lyon, 42023, Saint-Etienne (France); Tavernier, Emmanuelle [Service Hematologie Clinique, Institut de Cancerologie de la Loire, 42270, Saint-Priest-en-Jarez (France) [Service Hematologie Clinique, Institut de Cancerologie de la Loire, 42270, Saint-Priest-en-Jarez (France); CNRS UMR 5239, Universite de Lyon, 42023, Saint-Etienne (France); Carasevici, Eugen [Department of Immunology, Gr. T. Popa University of Medicine and Pharmacy, 700115, Iasi (Romania)] [Department of Immunology, Gr. T. Popa University of Medicine and Pharmacy, 700115, Iasi (Romania); Guyotat, Denis [Service Hematologie Clinique, Institut de Cancerologie de la Loire, 42270, Saint-Priest-en-Jarez (France) [Service Hematologie Clinique, Institut de Cancerologie de la Loire, 42270, Saint-Priest-en-Jarez (France); CNRS UMR 5239, Universite de Lyon, 42023, Saint-Etienne (France); Campos, Lydia [Laboratoire Hematologie, CHU de Saint-Etienne, 42055, Saint-Etienne (France) [Laboratoire Hematologie, CHU de Saint-Etienne, 42055, Saint-Etienne (France); CNRS UMR 5239, Universite de Lyon, 42023, Saint-Etienne (France)

2011-11-01

107

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

PubMed Central

Ligands by binding to G protein coupled receptors (GPCRs) stimulate dissociation of heterotrimeric G proteins into G? and G?? subunits. Released G? and G?? subunits induce discrete signaling cues that differentially regulate focal adhesion kinase (FAK) activity and endothelial barrier function. Activation of G proteins downstream of receptors such as protease activated receptor 1 (PAR1) and histamine receptors rapidly increases endothelial permeability which reverses naturally within the following one to two hours. However, activation of G proteins coupled to the sphingosine-1-phosphate receptor 1 (S1P1) signal cues that enhance basal barrier endothelial function and restore endothelial barrier function following the increase in endothelial permeability by edemagenic agents. Intriguingly, both PAR1 and S1P1 activation stimulates FAK activity, which associates with alteration in endothelial barrier function by these agonists. In this review, we focus on the role of the G protein subunits downstream of PAR1 and S1P1 in regulating FAK activity and endothelial barrier function. PMID:21640127

Thennes, Tracy; Mehta, Dolly

2011-01-01

108

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

109

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

Microsoft Academic Search

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

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

2007-01-01

110

Similarities between heterophilic and homophilic cadherin adhesion  

E-print Network

with chicken N-cadherin, canine E-cadherin, and Xenopus C-cadherin. Both qual- itative bead aggregation not intermix (14, 17). Electron microscopy studies similarly suggested that epithelial E-cadherin (E-CAD) a requires the cadherin family of calcium-dependent glycoproteins. A widely held view is that protein

Gardel, Margaret

111

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

E-print Network

Biomimetic soy protein nanocomposites with calcium carbonate crystalline arrays for use as wood 2010 Available online 21 March 2010 Keywords: Wood glue Calcium carbonate Gecko adhesion Soy protein crosslinking of calcium, carbonate, hydroxyl ions in the adhesive greatly improving the water- resistance

112

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

113

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

Microsoft Academic Search

Vascular adhesion protein-1 (VAP-1) is an endothelial adhesion molecule that possesses semicarbazide-sensitive amine oxidase (SSAO) activity and is involved in leukocyte recruitment. Leukocyte adhesion to retinal vessels is a predominant feature of experimentally induced diabetic retinopathy (DR). However, the role of VAP-1 in this process is unknown. Diabetes was induced by i.p. injection of Streptozotocin in Long–Evans rats. The specific

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

2009-01-01

114

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

115

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

116

Focal adhesion linker proteins expression of fibroblast related to adhesion in response to different transmucosal abutment surfaces  

PubMed Central

PURPOSE To evaluate adherence of human gingival fibroblasts (HGFs) to transmucosal abutment of dental implant with different surface conditions with time and to investigate the roles of focal adhesion linker proteins (FALPs) involved in HGFs adhesion to abutment surfaces. MATERIALS AND METHODS Morphologies of cultured HGFs on titanium and ceramic discs with different surface were observed by scanning electron microscopy. Biocompatibility and focal adhesion were evaluated by ultrasonic wave application and cell viability assay. FALPs expression levels were assessed by RT-PCR and western blot. RESULTS There seemed to be little difference in biocompatibility and adhesion strength of HGFs depending on the surface conditions and materials. In all experimental groups, the number of cells remaining on the disc surface after ultrasonic wave application increased more than 2 times at 3 days after seeding compared to 1-day cultured cells and this continued until 7 days of culture. FALPs expression levels, especially of vinculin and paxillin, also increased in 5-day cultured cells compared to 1-day cultured fibroblasts on the disc surface. CONCLUSION These results might suggest that the strength of adhesion of fibroblasts to transmucosal abutment surfaces increases with time and it seemed to be related to expressions of FALPs. PMID:24049577

Moon, Yeon-Hee; Yoon, Mi-Kyeong; Moon, Jung-Sun; Kang, Jee-Hae; Kim, Sun-Hun; Yang, Hong-Seo

2013-01-01

117

Expression patterns of focal adhesion associated proteins in the developing retina  

Microsoft Academic Search

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

Ming Li; Donald S. Sakaguchi

2002-01-01

118

Thin films of polymer mimics of cross-linking mussel adhesive proteins deposited by matrix assisted pulsed laser evaporation  

NASA Astrophysics Data System (ADS)

Mussels secrete specialized adhesives known as mussel adhesive proteins, which allow attachment of the organisms to underwater marine environments. Obtaining large quantities of naturally derived mussel adhesive proteins adhesives has proven to date rather problematic, thus, synthetic analogs of mussel adhesive proteins have recently been developed. We report deposition of 1:100 and 1:1000 poly[(3,4-dihydroxystyrene)-co-styrene)] mussel adhesive protein analogs by matrix assisted pulsed laser evaporation (MAPLE) using an ArF* excimer laser source. The deposited films have been evaluated for their antifouling behavior. The MAPLE-deposited synthetic mussel adhesive protein analog thin films are homogenous and adhesive, making the use of these materials in thin film form a viable option.

Cristescu, R.; Mihailescu, I. N.; Stamatin, I.; Doraiswamy, A.; Narayan, R. J.; Westwood, G.; Wilker, J. J.; Stafslien, S.; Chisholm, B.; Chrisey, D. B.

2009-03-01

119

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

Microsoft Academic Search

Despite the biodegradability, non-toxicity, and renewability, commercially available soy protein-based adhesives still have not been widely adopted by industry, partially due to their disappointing performances, i.e., low glue strength in the dry state and no glue strength in the wet state. In this study, biomimetic soy protein\\/CaCO3 hybrid wood glue was devised and an attempt made to improve the adhesion

Dagang Liu; Huihuang Chen; Peter R. Chang; Qinglin Wu; Kaifu Li; Litao Guan

2010-01-01

120

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

PubMed

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

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

2013-12-14

121

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

122

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

123

Adhesive Proteins of Stalked and Acorn Barnacles Display Homology with Low Sequence Similarities  

PubMed Central

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

124

Evaluation of endothelial cell adhesion onto different protein/gold electrodes by EIS.  

PubMed

To study cell attachment to biomaterials, several proteins such as fibronectin, collagen IV, heparin, immunoglobulin G, and albumin have been deposited onto polystyrene adsorbed on a self-assembled monolayer (silane or thiol) on glass or gold, respectively. The different steps of this multilayer assembly have been characterized by electrochemical impedance spectroscopy (EIS). These data are compared to those of adhesion rate, viability percentage, and cytoskeleton labeling for a better understanding of the cell adhesion process to each protein. All the proteins are endothelial cell adhering biomolecules but not with the same features. A linear relationship has been established between adhesion rate and resistance of the endothelial cell/protein interface for all negatively charged proteins. PMID:17477444

Bouafsoun, Amira; Helali, Saloua; Othmane, Ali; Kerkeni, Abdelhamid; Prigent, Anne-France; Jaffrézic-Renault, Nicole; Bessueille, François; Léonard, Didier; Ponsonnet, Laurence

2007-05-10

125

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

126

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

127

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

128

Adhesion mechanism in a DOPA-deficient foot protein from green mussels†  

PubMed Central

The holdfast or byssus of Asian green mussels, Perna viridis, contains a foot protein, pvfp-1, that differs in two respects from all other known adhesive mussel foot proteins (mfp): (1) instead of the hallmark L-3,4-dihydroxyphenylalanine (DOPA) residues in mfp-1, for example, pvfp-1 contains C2-mannosyl-7-hydroxytryptophan (Man7OHTrp). (2) In addition, pvfp-1 chains are not monomeric like mfp-1 but trimerized by collagen and coiled-coil domains near the carboxy terminus after a typical domain of tandemly repeated decapeptides. Here, the contribution of these peculiarities to adhesion was examined using a surface forces apparatus (SFA). Unlike previously studied mfp-1s, pvfp-1 showed significant adhesion to mica and, in symmetric pvfp-1 films, substantial cohesive interactions were present at pH 5.5. The role of Man7OHTrp in adhesion is not clear, and a DOPA-like role for Man7OHTrp in metal complexation (e.g., Cu2+, Fe3+) was not observed. Instead, cation–? interactions with low desolvation penalty between Man7OHTrp and lysyl side chains and conformational changes (raveling and unraveling of collagen helix and coiled-coil domains) are the best explanations for the strong adhesion between pvfp-1 monomolecular films. The strong adhesion mechanism induced by cation–? interactions and conformational changes in pvfp-1 provides new insights for the development of biomimetic underwater adhesives. PMID:23105946

Hwang, Dong Soo; Zeng, Hongbo; Lu, Qingye; Israelachvili, Jacob; Waite, J. Herbert

2012-01-01

129

Characteristics and Molecular Mechanism of Adhesion Proteins on Reused Hemodialysis Membranes  

Microsoft Academic Search

In order to study the mechanism of protein adhesion on the Fresenius F6 polysulfone membrane dialyzer, two-dimensional gel electrophoresis, LC-ESI-MS\\/MS and bioinformatics methods were used to analyze the protein which adhered to the dialyzer membrane. Six of the adhered proteins account for more than 50% of the total 179 proteins, i.e. ficolin precursor, complement C3 precursor, 3 variants of MASP1

Xiulin Xu; Yujing Yang; Naishuo Zhu

2009-01-01

130

Rho and Rab Small G Proteins Coordinately Reorganize Stress Fibers and Focal Adhesions in MDCK Cells  

Microsoft Academic Search

The Rho subfamily of the Rho small G protein family (Rho) regulates formation of stress fibers and focal adhesions in many types of cultured cells. In moving cells, dynamic and coordinate disassembly and reassembly of stress fibers and focal adhesions are observed, but the precise mechanisms in the regulation of these processes are poorly understood. We previously showed that 12-O-tetradecanoylphorbol-13-acetate

Hiroshi Imamura; Kenji Takaishi; Katsutoshi Nakano; Atsuko Kodama; Hideto Oishi; Hitoshi Shiozaki; Morito Monden; Takuya Sasaki; Yoshimi Takai

1998-01-01

131

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

132

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

PubMed Central

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, laminin ?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

2011-01-01

133

Single Adhesive Nanofibers from a Live Diatom Have the Signature Fingerprint of Modular Proteins  

PubMed Central

The adhesive and mechanical properties of a cell-substratum adhesive secreted by live diatom cells were examined in situ using atomic force microscopy. The resulting force curves have a regular saw-tooth pattern, the characteristic fingerprint of modular proteins, and when bridged between tip and surface can repeatedly be stretched and relaxed resulting in precisely overlaying saw-tooth curves (up to ?600 successive cycles). The average rupture force of the peaks is 0.794 ± 0.007 (mean ± SE) nN at a loading rate of 0.8 ?m/s and the average persistence length is 0.026 ± <0.001 (mean ± SE) nm (fit using the worm-like chain model). We propose that we are pulling on single adhesive nanofibers, each a cohesive unit composed of a set number of modular proteins aligned in register. Furthermore, we can observe and differentiate when up to three adhesive nanofibers are pulled based upon multimodal distributions of force and persistence length. The high force required for bond rupture, high extensibility (?1.2 ?m), and the accurate and rapid refolding upon relaxation, together provide strong and flexible properties ideally suited for the cell-substratum adhesion of this fouling diatom and allow us to understand the mechanism responsible for the strength of adhesion. PMID:16169972

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

2005-01-01

134

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

PubMed Central

Integrin adhesion receptors mediate cell–cell and cell–extracellular matrix interactions, which control cell morphology and migration, differentiation, and tissue integrity. Integrins recruit multimolecular adhesion complexes to their cytoplasmic domains, which provide structural and mechanosensitive signaling connections between the extracellular and intracellular milieux. The different functions of specific integrin heterodimers, such as ?4?1 and ?5?1, have been attributed to distinct signal transduction mechanisms that are initiated by selective recruitment of adhesion complex components to integrin cytoplasmic tails. Here, we report the isolation of ligand-induced adhesion complexes associated with wild-type ?4?1 integrin, an activated ?4?1 variant in the absence of the ? cytoplasmic domain (X4C0), and a chimeric ?4?1 variant with ?5 leg and cytoplasmic domains (?4P?5L), and the cataloguing of their proteomes by MS. Using hierarchical clustering and interaction network analyses, we detail the differential recruitment of proteins and highlight enrichment patterns of proteins to distinct adhesion complexes. We identify previously unreported components of integrin adhesion complexes and observe receptor-specific enrichment of molecules with previously reported links to cell migration and cell signaling processes. Furthermore, we demonstrate colocalization of MYO18A with active integrin in migrating cells. These datasets provide a resource for future studies of integrin receptor-specific signaling events. PMID:22623428

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

2012-01-01

135

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

136

Adhesive properties of soy proteins modified by sodium dodecyl sulfate and sodium dodecylbenzene sulfonate  

Microsoft Academic Search

A study was conducted on adhesive and water-resistance properties of soy protein isolates modified by sodium dodecyl sulfate\\u000a (SDS) (0.5, 1, and 3%) and sodium dodecylbenzene sulfonate (SDBS) (0.5, 1, and 3%) and applied on walnut, cherry, and pine\\u000a plywoods. Soy proteins modified by 0.5 and 1% SDS showed greater shear strengths than did unmodified protein. One percent\\u000a SDS modification

Weining Huang; Xiuzhi Sun

2000-01-01

137

Extraction of Jatropha curcas proteins and application in polyketone-based wood adhesives  

Microsoft Academic Search

Jatropha proteins were successfully extracted from the corresponding seeds using the principle of isoelectric precipitation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), elemental analysis and Fourier transform infrared spectroscopy (FTIR) were used to analyze the obtained proteins. The proteins were used at different contents as a reactive component in polyketone-based wood adhesive formulations. The stability, structure, pot-life and performance of

A. I. Hamarneh; H. J. Heeres; A. A. Broekhuis; F. Picchioni

2010-01-01

138

Protein-to-film adhesion as examined by amino analysis of protein binding to three different packaging films.  

PubMed

A weak protein solution extracted from chicken breast meat was exposed to three types of packaging materials. The crude myofibrillar protein solution (12.0 mg protein/mL buffer) was suspended in a 0.6M NaCl/NaPO4 buffer, then placed in bags made from either polyethylene (nonbinding film), a nylon blend (binding film), or Surlyn (binding film). Two separate experiments were conducted to determine the effects of exposure time at a constant temperature and varying endpoint exposure temperatures on the amount of bound protein by amino acid analysis. Bound amino acids were quantified and grouped by class based on functional side group. It was theorized that differences in the amount of bound amino acid class was linked to the mechanism by which the meat-to-film binding occurs. The protein solution was sealed in bags and held in a water bath for 5 s, 20 min, 40 min, and 60 min at 25.8 C for the timed experiment and heated from 25.8 C to 40, 55, 70, and 80 C for the temperature experiment. Protein adhesion occurred due to exposure of the solution to all films at 25.8 C. Greater protein adhesion was found in the two binding films than in the nonbinding film after 60 min of exposure. Heating the protein solution increased adhesion for the Surlyn film and showed a clear delineation in the degree of binding between the film types. Surlyn bound the most protein, followed by the nylon blend and then polyethylene. Bound protein increased in the Surlyn film with heating to 80 C, whereas the polyethylene did not show an increase in the amount of bound protein. Increases in binding observed between 55 and 80 C for Surlyn may be associated with transitional and conformational changes in muscle proteins that affect the adhesion of meat to the film surface. PMID:9603364

Clardy, C B; Han, I Y; Acton, J C; Wardlaw, F B; Bridges, W B; Dawson, P L

1998-05-01

139

Interaction between urokinase receptor and heat shock protein MRJ enhances cell adhesion.  

PubMed

The urokinase-type plasminogen activator receptor (uPAR) has diverse biological functions including roles in proteolysis, cell adhesion and cellular signaling. We identified a heat shock protein MRJ (DNAJB6) as a novel uPAR-interacting protein in a yeast two-hybrid screen and confirmed the interaction and co-localization by GST-pull down assays, and co-immunoprecipitation in cells transfected with MRJ. Endogenous interaction between uPAR and MRJ was also detected in breast cancer MDA-MB-231 cells. Deletion mapping demonstrated that the C-terminal region of MRJ is required to mediate its interaction with uPAR. To understand the biological function of the uPAR-MRJ complex, we determined whether MRJ regulated uPAR mediated adhesion to vitronectin in human embryonic kidney (HEK) 293 cells stably transfected with uPAR. After transfection with full length MRJ, there was a 50% increase in cell adhesion compared to the mock transfected control (p<0.01). This increase in adhesion is dependent on the uPAR/full length MRJ interaction as cells transfected with the mutant construct containing only N-terminal region or C-terminal region of MRJ had no increase in cell adhesion. The observed increase in adhesion to vitronectin by MRJ was also blocked by an anti-uPAR domain I antibody suggesting that the induced adhesion is at least in part contributed by uPAR on the cell surface. These data provide a novel mechanism by which uPAR plays a role in cell adhesion to vitronectin. PMID:20372789

De Bock, Charles Edo; Lin, Zhen; Mekkawy, Ahmed H; Byrne, Jennifer A; Wang, Yao

2010-05-01

140

Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin  

PubMed Central

Background Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Methods Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-?B activation, and hence cell adhesion to human umbilical vein endothelial cells (HUVECs). 5-Aminoimidazole-4-carboxamide 1-?-D-ribofuranoside (AICAR), an AMP-activated protein kinase (AMPK) activator, was used to determine the regulatory role of AMPK on HCC adhesion to the endothelium in regard to the resistin effects. Results Treatment with resistin increased the adhesion of SK-Hep1 cells to HUVECs and concomitantly induced NF-?B activation, as well as ICAM-1 and VCAM-1 expressions in SK-Hep1 cells. Using specific blocking antibodies and siRNAs, we found that resistin-induced SK-Hep1 cell adhesion to HUVECs was through NF-?B-regulated ICAM-1 and VCAM-1 expressions. Moreover, treatment with AICAR demonstrated that AMPK activation in SK-Hep1 cells significantly attenuates the resistin effect on SK-Hep1 cell adhesion to HUVECs. Conclusions These results clarify the role of resistin in inducing HCC adhesion to the endothelium and demonstrate the inhibitory effect of AMPK activation under the resistin stimulation. Our findings provide a notion that resistin play an important role to promote HCC metastasis and implicate AMPK may be a therapeutic target to against HCC metastasis. PMID:24555415

2014-01-01

141

Hydrophobic enhancement of Dopa-mediated adhesion in a mussel foot protein  

PubMed Central

Dopa (3,4-dihydroxyphenylalanine) is recognized as a key chemical signature of mussel adhesion and has been adopted into diverse synthetic polymer systems. Dopa’s notorious susceptibility to oxidation, however, poses significant challenges to the practical translation of mussel adhesion. Using a Surface Forces Apparatus to investigate the adhesion of Mfp3 (mussel foot protein 3) slow, a hydrophobic protein variant of the Mfp3 family in the plaque, we have discovered a subtle molecular strategy correlated with hydrophobicity that appears to compensate for Dopa instability. At pH 3, where Dopa is stable, Mfp3 slow like Mfp3 fast adhesion to mica is directly proportional to the mol% of Dopa present in the protein. At pH 5.5 and 7.5, however, loss of adhesion in Mfp3 slow was less than half that occurring in Mfp3 fast, purportedly because Dopa in Mfp3 slow is less prone to oxidation. Indeed, cyclic voltammetry showed that the oxidation potential of Dopa in Mfp3 slow is significantly higher than in Mfp3 fast at pH 7.5. A much greater difference between the two variants was revealed in the interaction energy of two symmetric Mfp3 slow films (Ead = ?3 mJ/m2). This energy corresponds to the energy of protein cohesion which is notable for its reversibility and pH-independence. Exploitation of aromatic hydrophobic sequences to protect Dopa against oxidation as well as to mediate hydrophobic and H-bonding interactions between proteins provides new insights for developing effective artificial underwater adhesives. PMID:23214725

Wei, Wei; Yu, Jing; Broomell, Christopher; Israelachvili, Jacob N.; Waite, J. Herbert

2013-01-01

142

Adhesion mechanisms of the mussel foot proteins mfp-1 and mfp-3  

PubMed Central

Mussels adhere to a variety of surfaces by depositing a highly specific ensemble of 3,4-dihydroxyphenyl-l-alanine (DOPA) containing proteins. The adhesive properties of Mytilus edulis foot proteins mfp-1 and mfp-3 were directly measured at the nano-scale by using a surface forces apparatus (SFA). An adhesion energy of order W ?3 × 10?4 J/m2 was achieved when separating two smooth and chemically inert surfaces of mica (a common alumino-silicate clay mineral) bridged or “glued” by mfp-3. This energy corresponds to an approximate force per plaque of ?100 gm, more than enough to hold a mussel in place if no peeling occurs. In contrast, no adhesion was detected between mica surfaces bridged by mfp-1. AFM imaging and SFA experiments showed that mfp-1 can adhere well to one mica surface, but is unable to then link to another (unless sheared), even after prolonged contact time or increased load (pressure). Although mechanistic explanations for the different behaviors are not yet possible, the results are consistent with the apparent function of the proteins, i.e., mfp-1 is disposed as a “protective” coating, and mfp-3 as the adhesive or “glue” that binds mussels to surfaces. The results suggest that the adhesion on mica is due to weak physical interactions rather than chemical bonding, and that the strong adhesion forces of plaques arise as a consequence of their geometry (e.g., their inability to be peeled off) rather than a high intrinsic surface or adhesion energy, W. PMID:17360430

Lin, Qi; Gourdon, Delphine; Sun, Chengjun; Holten-Andersen, Niels; Anderson, Travers H.; Waite, J. Herbert; Israelachvili, Jacob N.

2007-01-01

143

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

144

Amyloid Precursor Protein Is an Autonomous Growth Cone Adhesion Molecule Engaged in Contact Guidance  

PubMed Central

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

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

2013-01-01

145

Diversity of bone matrix adhesion proteins modulates osteoblast attachment and organization of actin cytoskeleton.  

PubMed

Interaction of cells with extracellular matrix is an essential event for differentiation, proliferation and activity of osteoblasts. In bone, binding of osteoblasts to bone matrix is required to determine specific activities of the cells and to synthesize matrix bone proteins. Integrins are the major cell receptors involved in the cell linkage to matrix proteins such as fibronectin, type I collagen and vitronectin, via the RGD-sequences. In this study, cultures of osteoblast-like cells (Saos-2) were done on coated glass coverslips in various culture conditions: DMEM alone or DMEM supplemented with poly-L-lysine (PL), fetal calf serum (FCS), fibronectin (FN), vitronectin (VN) and type I collagen (Col-I). The aim of the study was to determine the specific effect of these bone matrix proteins on cell adherence and morphology and on the cytoskeleton status. Morphological characteristics of cultured cells were studied using scanning electron microscopy and image analysis. The heterogeneity of cytoskeleton was studied using fractal analysis (skyscrapers and blanket algorithms) after specific preparation of cells to expose the cytoskeleton. FAK and MAPK signaling pathways were studied by western blotting in these various culture conditions. Results demonstrated that cell adhesion was reduced with PL and VN after 240 min. After 60 min of adhesion, cytoskeleton organization was enhanced with FN, VN and Col-I. No difference in FAK phosphorylation was observed but MAPK phosphorylation was modulated by specific adhesion on extracellular proteins. These results indicate that culture conditions modulate cell adhesion, cytoskeleton organization and intracellular protein pathways according to extracellular proteins present for adhesion. PMID:24735942

Demais, V; Audrain, C; Mabilleau, G; Chappard, D; Baslé, M F

2014-06-01

146

Controlling Primary Hepatocyte Adhesion and Spreading on Protein-Free Polyelectrolyte Multilayer Films  

E-print Network

Controlling Primary Hepatocyte Adhesion and Spreading on Protein-Free Polyelectrolyte Multilayer@egr.msu.edu This Communication describes the successful attachment and spreading of primary hepatocytes on polyelectrolyte for the first time that primary hepatocytes attached, spread, and maintained differentiated function

Lee, Ilsoon

147

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

PubMed

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

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

2012-01-01

148

Effect of milk proteins on adhesion of bacteria to stainless steel surfaces.  

PubMed

Stainless steel coupons were treated with skim milk and subsequently challenged with individual bacterial suspensions of Staphylococcus aureus, Pseudomonas fragi, Escherichia coli, Listeria monocytogenes, and Serratia marcescens. The numbers of attached bacteria were determined by direct epifluorescence microscopy and compared with the attachment levels on clean stainless steel with two different surface finishes. Skim milk was found to reduce adhesion of S. aureus, L. monocytogenes, and S. marcescens. P. fragi and E. coli attached in very small numbers to the clear surfaces, making the effect of any adsorbed protein layer difficult to assess. Individual milk proteins alpha-casein, beta-casein, kappa-casein, and alpha-lactalbumin were also found to reduce the adhesion of S. aureus and L. monocytogenes. The adhesion of bacteria to samples treated with milk dilutions up to 0.001% was investigated. X-ray photoelectron spectroscopy was used to determine the proportion of nitrogen in the adsorbed films. Attached bacterial numbers were inversely related to the relative atomic percentage of nitrogen on the surface. A comparison of two types of stainless steel surface, a 2B and a no. 8 mirror finish, indicated that the difference in these levels of surface roughness did not greatly affect bacterial attachment, and reduction in adhesion to a milk-treated surface was still observed. Cross-linking of adsorbed proteins partially reversed the inhibition of bacterial attachment, indicating that protein chain mobility and steric exclusion may be important in this phenomenon. PMID:10508087

Barnes, L M; Lo, M F; Adams, M R; Chamberlain, A H

1999-10-01

149

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

PubMed Central

The myelin Po protein is believed to hold myelin together via interactions of both its extracellular and cytoplasmic domains. We have already shown that the extracellular domains of Po can interact in a homophilic manner (Filbin, M.T., F.S. Walsh, B.D. Trapp, J.A. Pizzey, and G.I. Tennekoon. 1990. Nature (Lond.). 344:871-872). In addition, we have shown that for this homophilic adhesion to take place, the cytoplasmic domain of Po must be intact and most likely interacting with the cytoskeleton; Po proteins truncated in their cytoplasmic domains are not adhesive (Wong, M.H., and M.T. Filbin, 1994. J. Cell Biol. 126:1089-1097). To determine if the presence of these truncated forms of Po could have an effect on the functioning of the full-length Po, we coexpressed both molecules in CHO cells. The adhesiveness of CHO cells expressing both full-length Po and truncated Po was then compared to cells expressing only full-length Po. In these coexpressors, both the full-length and the truncated Po proteins were glycosylated. They reached the surface of the cell in approximately equal amounts as shown by an ELISA and surface labeling, followed by immunoprecipitation. Furthermore, the amount of full-length Po at the cell surface was equivalent to other cell lines expressing only full-length Po that we had already shown to be adhesive. Therefore, there should be sufficient levels of full-length Po at the surface of these coexpressors to measure adhesion of Po. However, as assessed by an aggregation assay, the coexpressors were not adhesive. By 60 min they had not formed large aggregates and were indistinguishable from the control transfected cells not expressing Po. In contrast, in the same time, the cells expressing only the full-length Po had formed large aggregates. This indicates that the truncated forms of Po have a dominant-negative effect on the adhesiveness of the full-length Po. Furthermore, from cross-linking studies, full-length Po, when expressed alone but not when coexpressed with truncated Po, appears to cluster in the membrane. We suggest that truncated Po exerts its dominant-negative effect by preventing clustering of full-length Po. We also show that colchicine, which disrupts microtubules, prevents adhesion of cells expressing only the full-length Po. This strengthens our suggestion that an interaction of Po with the cytoskeleton, either directly or indirectly, is required for adhesion to take place. PMID:8830780

1996-01-01

150

Adhesive properties of soy proteins modified by urea and guanidine hydrochloride  

Microsoft Academic Search

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

Weining Huang; Xiuzhi Sun

2000-01-01

151

Marine Surfaces and the Expression of Specific Byssal Adhesive Protein Variants in Mytilus  

Microsoft Academic Search

:  \\u000a Mytilus foot protein-3 (Mfp-3) is a highly polymorphic protein family located in the byssal adhesive plaques of blue mussels. Previous\\u000a evidence suggested that the deposition of selected Mfp-3 variants might be influenced by the type of surface to which the\\u000a mussel attaches; therefore, we undertook to rigorously investigate whether a correlation exists between surface type and Mfp-3\\u000a variants. Two

Renee Y. Floriolli; Johannes von Langen; J. Herbert Waite

2000-01-01

152

Ena\\/VASP Proteins Can Regulate Distinct Modes of Actin Organization at Cadherin-adhesive Contacts  

Microsoft Academic Search

Functional interactions between classical cadherins and the actin cytoskeleton involve diverse actin activities, including filament nucleation, cross-linking, and bundling. In this report, we explored the capacity of Ena\\/VASP proteins to regulate the actin cytoskeleton at cadherin-adhesive contacts. We extended the observation that Ena\\/vasodilator-stimulated phosphoprotein (VASP) proteins localize at cell- cell contacts to demonstrate that E-cadherin homophilic ligation is sufficient to

Jeanie A. Scott; Annette M. Shewan; Nicole R. den Elzen; Joseph J. Louriero; Frank B. Gertler; Alpha S. Yap

2005-01-01

153

Effects of Surface Properties on Adhesion of Protein to Biomaterials  

E-print Network

. Protein was sensitive to micro-scale surface roughness and especially favored the nano-porous surface feature. Results indicated that the unpurified SWCNTs influenced crystallization of HDPE and resulted in a nano-porous structure, which enhanced...

Feng, Fangzhou

2011-10-21

154

Optically degradable dendrons for temporary adhesion of proteins to DNA.  

PubMed

Experimental studies and molecular dynamics modeling demonstrate that multivalent dendrons can be used to temporarily glue proteins and DNA together with high affinity. We describe N-maleimide-cored polyamine dendrons that can be conjugated with free cysteine residues on protein surfaces through 1,4-conjugate addition to give one-to-one protein-polymer conjugates. We used a genetically engineered cysteine mutant of class II hydrophobin (HFBI) and a single-chain Fragment variable (scFv) antibody as model proteins for the conjugation reactions. The binding affinity of the protein-dendron conjugates towards DNA was experimentally assessed by using the ethidium bromide displacement assay. The binding was found to depend on the generation of the dendron, with the second generation having a stronger affinity than the first generation. Thermodynamic parameters of the binding were obtained from molecular dynamics modeling, which showed that the high binding affinity for each system is almost completely driven by a strong favorable binding enthalpy that is opposed by unfavorable binding entropy. A short exposure to UV (lambda approximately 350 nm) can cleave the photolabile o-nitrobenzyl-linked binding ligands from the surface of the dendron, which results in loss of the multivalent binding interactions and triggers the release of the DNA and protein. The timescale of the release is very rapid and the binding partners can be efficiently released after 3 min of UV exposure. PMID:20437425

Kostiainen, Mauri A; Kotimaa, Juha; Laukkanen, Marja-Leena; Pavan, Giovanni M

2010-06-18

155

Identification of Proteins Associated with Adhesive Prints from Holothuria dofleinii Cuvierian Tubules.  

PubMed

Cuvierian tubules are expelled as a defence mechanism against predators by various species within the family Holothuridae. When the tubules are expelled, they become sticky almost immediately and ensnare the predator. The mechanism of this rapid adhesion is not clear, but proteins on the surface of the expelled tubules are widely believed to be involved. This study has examined such proteins from Holothuria dofleinii, sourced from adhesive prints left on glass after the removal of adhered tubules. Gel electrophoresis showed that seven strongly staining protein bands were consistently present in all samples, with molecular masses ranging from 89 to 17 kDa. N-terminal sequence data was obtained from two bands, while others seemed blocked. Tandem mass spectrometry-based sequencing of tryptic peptides derived from individual protein bands indicated that the proteins were unlikely to be homopolymers. PCR primers designed using the peptide sequences enabled us to amplify, clone and sequence cDNA segments relating to four gel bands; for each, the predicted translation product contained other peptide sequences observed for that band that had not been used in primer design. Database searches using the peptide and cDNA-encoded sequences suggest that two of the seven proteins are novel and one is a C-type lectin, while-surprisingly-at least three of the other four are closely related to enzymes associated with the pentose phosphate cycle and glycolysis. We discuss precedents in which lectins and metabolic enzymes are involved in attachment and adhesion phenomena. PMID:25086572

Peng, Yong Y; Glattauer, Veronica; Skewes, Timothy D; McDevitt, Andrew; Elvin, Christopher M; Werkmeister, Jerome A; Graham, Lloyd D; Ramshaw, John A M

2014-12-01

156

Cingulate cortex synaptic terminal proteins and neural cell adhesion molecule in schizophrenia.  

PubMed

The neuronal organization and patterns of afferent innervation are abnormal in the cingulate cortex in schizophrenia, and associated changes in synaptic terminals could be present. A panel of monoclonal antibodies was defined with biochemical and fusion protein studies as detecting syntaxin (antibody SP6), synaptophysin (antibody SP4) and synaptosomal-associated protein-25 (antibody SP12). These antibodies and a polyclonal antibody reactive with neural cell adhesion molecule were used to investigate the cingulate cortex in schizophrenia. Immunocytochemistry indicated that syntaxin immunoreactivity had a considerably wider distribution than synaptophysin. Overall, multivariate analysis indicated increased synaptic terminal protein immunoreactivity in schizophrenia compared to controls (P=0.004). Controlled for age and post mortem interval, syntaxin immunoreactivity was significantly elevated in schizophrenia (P=0.004), and neural cell adhesion molecule immunoreactivity was also elevated (P=0.05). The neural cell adhesion molecule to synaptophysin ratio was increased (P=0.005), possibly indicating the presence of less mature synapses in schizophrenia. Elevated syntaxin immunoreactivity is consistent with increased glutamatergic afferents to the cingulate cortex in schizophrenia, and combined with the neural cell adhesion molecule to synaptophysin ratio results suggests that synaptic function in this region in schizophrenia may be abnormal. PMID:9135092

Honer, W G; Falkai, P; Young, C; Wang, T; Xie, J; Bonner, J; Hu, L; Boulianne, G L; Luo, Z; Trimble, W S

1997-05-01

157

Amassin, an olfactomedin protein, mediates the massive intercellular adhesion of sea urchin coelomocytes  

PubMed Central

Sea urchins have a fluid-filled body cavity, the coelom, containing four types of immunocytes called coelomocytes. Within minutes after coelomic fluid is removed from the body cavity, a massive cell–cell adhesion of coelomocytes occurs. This event is referred to as clotting. Clotting is thought to be a defense mechanism against loss of coelomic fluid if the body wall is punctured, and it may also function in the cellular encapsulation of foreign material and microbes. Here we show that this intercoelomocyte adhesion is mediated by amassin, a coelomic plasma protein with a relative molecular mass (Mr) of 75 kD. Amassin forms large disulfide-bonded aggregates that adhere coelomocytes to each other. One half of the amassin protein comprises an olfactomedin (OLF) domain. Structural predictions show that amassin and other OLF domain-containing vertebrate proteins share a common architecture. This suggests that other proteins of the OLF family may function in intercellular adhesion. These findings are the first to demonstrate a function for a protein of the OLF family. PMID:12591917

Hillier, Brian J.; Vacquier, Victor D.

2003-01-01

158

Use of soy proteins in polyketone-based wood adhesives  

Microsoft Academic Search

This paper describes the preparation of aqueous emulsions consisting of soy proteins and chemically modified thermosetting aliphatic polyketones. Emulsions were prepared in a range of total solids contents and different addition protocols were tested. Room temperature stability and structure of the prepared emulsions were studied as a function of time using dynamic light scattering, rheology, cryo-scanning electron microscopy (Cryo-SEM) and

A. I. Hamarneh; H. J. Heeres; A. A. Broekhuis; K. A. Sjollema; Y. Zhang; F. Picchioni

2010-01-01

159

Co-polypeptides of 3,4-dihydroxyphenylalanine and l-lysine to mimic marine adhesive protein  

Microsoft Academic Search

Co-polypeptides containing 3,4-dihydroxyphenylalanine (DOPA) and l-lysine were synthesized to mimic the marine adhesive proteins through ring-opening polymerizations. The effects of composition, molecular weight, and curing agents on the adhesive properties, swelling, and degradation behavior of synthetic polypeptide were investigated. Ferric ion was introduced to the system to optimize both adhesive strength and water resistance, simulating the specificity of metal-mediated cross-linking

Jing Wang; Changsheng Liu; Xin Lu; Min Yin

2007-01-01

160

Lumican core protein inhibits melanoma cell migration via alterations of focal adhesion complexes.  

PubMed

Lumican is a small leucine-rich proteoglycan (SLRP) of the extracellular matrix (ECM) with anti-tumor activity. We recently demonstrated that lumican inhibits the migration of melanoma cells and identified beta1 integrin as mediator of this effect [M.F. D'Onofrio, S. Brézillon, T. Baranek, C. Perreau, P.J. Roughley, F.X. Maquart, Y. Wegrowski, Identification of beta1 integrin as mediator of melanoma cell adhesion to lumican, Biochem. Biophys. Res. Commun. 365 (2008) 266-272]. The aim of the present work was to study beta1 integrin, focal adhesion complexes, actin distribution and expression in the presence of lumican substratum in comparison to type I collagen or fibronectin substrata in A375 human melanoma cells. The protein distribution was investigated by immunocytochemistry and confocal microscopy. In parallel, their expression was evaluated by Western immunoblotting and Real-time Reverse Transcription-PCR analyses. The interaction of melanoma cells with the lumican substratum resulted in heterogeneous distribution of beta1 integrin on cell membrane after 24h of seeding. Concomitantly, a reorganization of actin stress fibers and a significant decrease in vinculin immunostaining at focal adhesion complexes were observed. No alteration of the expression was detected at protein and mRNA levels. However, a cytosolic accumulation of vinculin focal adhesion protein was observed on lumican substratum by confocal microscopy. Moreover, vinculin expression was significantly increased in cytosolic fractions in comparison to cells seeded on type I collagen or fibronectin substrata. Our results suggest that lumican induces an alteration of the link between actin filaments and beta1 integrin, characterized by a cytosolic accumulation of vinculin focal adhesion protein, which could lead to a destabilization of focal adhesion complexes. In addition, focal adhesion kinase phosphorylated at tyrosine-397 (pFAK) was significantly decreased. Therefore, the cytoskeleton remodeling and the decreased pFAK phosphorylation induced by lumican in melanoma cells might explain, at least in part, the anti-invasive effect of this SLRP. PMID:19394140

Brézillon, Stéphane; Radwanska, Agata; Zeltz, Cedric; Malkowski, Andrzej; Ploton, Dominique; Bobichon, Hélène; Perreau, Corinne; Malicka-Blaszkiewicz, Maria; Maquart, François-Xavier; Wegrowski, Yanusz

2009-09-28

161

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

PubMed

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

2002-09-01

162

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-Setala, Tiina; Soderlund, Hans; Penttila, Merja

2002-01-01

163

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

164

Polarity proteins and actin regulatory proteins are unlikely partners that regulate cell adhesion in the seminiferous epithelium during spermatogenesis  

PubMed Central

Summary In mammalian testis, spermatogenesis takes place in the seminiferous epithelium of the seminiferous tubule, which is composed of a series of cellular events. These include: (i) spermatogonial stem cell (SSC) renewal via mitosis and differentiation of SSC to spermatogenia, (ii) meiosis, (iii) spermiogenesis, and (iv) spermiation. Throughout these events, developing germ cells remain adhered to the Sertoli cell in the seminiferous epithelium amidst extensive cellular, biochemical, molecular and morphological changes to obtain structural support and nourishment. These events are coordinated via signal transduction at the cell-cell interface through cell junctions, illustrating the significance of cell junctions and adhesion in spermatogenesis. Additionally, developing germ cells migrate progressively across the seminiferous epithelium from the stem cell niche, which is located in the basal compartment near the basement membrane of the tunica propria adjacent to the interstitium. Recent studies have shown that some apparently unrelated proteins, such as polarity proteins and actin regulatory proteins, are in fact working in concert and synergistically to coordinate the continuous cyclic changes of adhesion at the Sertoli-Sertoli and Sertoli-germ cell interface in the seminiferous epithelium during the epithelial cycle of spermatogenesis, such that developing germ cells remain attached to the Sertoli cell in the epithelium while they alter in cell shape and migrate across the epithelium. In this review, we highlight the physiological significance of endocytic vesicle-mediated protein trafficking events under the influence of polarity and actin regulatory proteins in conferring cyclic events of cell adhesion and de-adhesion. Furthermore, these recent findings have unraveled some unexpected molecules to be targeted for male contraceptive development, which are also targets of toxicant-induced male reproductive dysfunction. PMID:21938683

Cheng, C. Yan; Wong, Elissa W.P.; Lie, Pearl P.Y.; Mruk, Dolores D.; Xiao, Xiang; Li, Michelle W.M.; Lui, Wing-Yee; Lee, Will M.

2014-01-01

165

Polarity proteins and actin regulatory proteins are unlikely partners that regulate cell adhesion in the seminiferous epithelium during spermatogenesis.  

PubMed

In mammalian testis, spermatogenesis takes place in the seminiferous epithelium of the seminiferous tubule, which is composed of a series of cellular events. These include: (i) spermatogonial stem cell (SSC) renewal via mitosis and differentiation of SSC to spermatogenia, (ii) meiosis, (iii) spermiogenesis, and (iv) spermiation. Throughout these events, developing germ cells remain adhered to the Sertoli cell in the seminiferous epithelium amidst extensive cellular, biochemical, molecular and morphological changes to obtain structural support and nourishment. These events are coordinated via signal transduction at the cell-cell interface through cell junctions, illustrating the significance of cell junctions and adhesion in spermatogenesis. Additionally, developing germ cells migrate progressively across the seminiferous epithelium from the stem cell niche, which is located in the basal compartment near the basement membrane of the tunica propria adjacent to the interstitium. Recent studies have shown that some apparently unrelated proteins, such as polarity proteins and actin regulatory proteins, are in fact working in concert and synergistically to coordinate the continuous cyclic changes of adhesion at the Sertoli-Sertoli and Sertoli-germ cell interface in the seminiferous epithelium during the epithelial cycle of spermatogenesis, such that developing germ cells remain attached to the Sertoli cell in the epithelium while they alter in cell shape and migrate across the epithelium. In this review, we highlight the physiological significance of endocytic vesicle-mediated protein trafficking events under the influence of polarity and actin regulatory proteins in conferring cyclic events of cell adhesion and de-adhesion. Furthermore, these recent findings have unraveled some unexpected molecules to be targeted for male contraceptive development, which are also targets of toxicant-induced male reproductive dysfunction. PMID:21938683

Cheng, C Y; Wong, E W P; Lie, P P Y; Mruk, D D; Xiao, X; Li, M W M; Lui, W-Y; Lee, W M

2011-11-01

166

The adapter proteins ADAP and Nck cooperate in T cell adhesion.  

PubMed

Nck adapter proteins link receptor and receptor-associated tyrosine kinases with proteins implicated in the regulation of the actin cytoskeleton. Nck is involved in a multitude of receptor-initiated signaling pathways and its physiological role thus covers aspects of tissue development and homeostasis, malignant transformation/invasiveness of tumour cells and also immune cell function. In T cells, changes of cell polarity and morphology associated with cellular activation and effector function crucially rely on the T cell receptor-mediated recruitment and activation of different actin-regulatory proteins to orchestrate and drive cytoskeletal reorganization at the immunological synapse. In a former approach to determine the interactome of Nck in human T cells, we identified the adapter protein ADAP as a Nck-interacting protein. This adhesion and degranulation-promoting adapter protein had already been implicated in the inside-out activation of integrins. Employing co-immunoprecipitations, we demonstrate that both Nck family members Nck1 and Nck2 coprecipitate with ADAP. Specifically, Nck interacts via its Src homology 2 domain with phosphorylated tyrosine Y595DDV and Y651DDV sites of ADAP. Moreover, we show that endogenous ADAP is phosphorylated in primary human T cell blasts and thus associates with Nck. At the functional level, ADAP and Nck adapter proteins cooperatively facilitate T cell adhesion to the LFA-1 ligand ICAM-1. Our data indicate that the ADAP/Nck complex might provide a means to link integrin activation with the actin cytoskeleton. PMID:24769494

Lettau, Marcus; Kliche, Stefanie; Kabelitz, Dieter; Janssen, Ottmar

2014-07-01

167

Understanding Marine Mussel Adhesion  

Microsoft Academic Search

In addition to identifying the proteins that have a role in underwater adhesion by marine mussels, research efforts have focused\\u000a on identifying the genes responsible for the adhesive proteins, environmental factors that may influence protein production,\\u000a and strategies for producing natural adhesives similar to the native mussel adhesive proteins. The production-scale availability\\u000a of recombinant mussel adhesive proteins will enable researchers

Heather G. Silverman; Francisco F. Roberto

2007-01-01

168

Focal adhesion protein-tyrosine kinase phosphorylated in response to cell attachment to fibronectin.  

PubMed Central

A homology-based cDNA cloning approach was used to identify a widely expressed protein-tyrosine kinase designated as "focal adhesion kinase" (FadK). The entire mouse FadK amino acid sequence was deduced from cDNA clones, revealing a large (119-kDa) non-membrane-spanning protein-tyrosine kinase that lacks Src-homology SH2 and SH3 domains. Immunostaining of BALB/c 3T3 fibroblasts revealed that FadK is concentrated in focal adhesions. FadK is phosphorylated on tyrosine in growing cultures of BALB/c 3T3 cells but contains little or no phosphotyrosine in cells detached by trypsinization. The tyrosine-phosphorylated state is regained within minutes when the cells are replated onto fibronectin. Activation of FadK may be an important early step in intracellular signal transduction pathways triggered in response to cell interactions with the extracellular matrix. Images PMID:1528852

Hanks, S K; Calalb, M B; Harper, M C; Patel, S K

1992-01-01

169

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

PubMed Central

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

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

2009-01-01

170

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

Microsoft Academic Search

Inflammatory leukocyte accumulation is a common feature of major ocular diseases, such as uveitis, diabetic retinopathy, and age-related macular degeneration. Vascular adhesion protein-1 (VAP-1), a cell surface and soluble molecule that possesses semi- carbazide-sensitive amine oxidase (SSAO) activity, is involved in leukocyte recruitment. However, the ex- pression of VAP-1 in the eye and its contribution to ocular inflammation are unknown.

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

2007-01-01

171

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

Microsoft Academic Search

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

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

2003-01-01

172

The effect of an RGD-containing fusion protein CBD-RGD in promoting cellular adhesion  

Microsoft Academic Search

The effect of a recombinant RGD (arginine-glycine-aspartic acid)-containing fusion protein, cellulose-binding domain (CBD)-RGD, on the cellular adhesion to a biomedical polyurethane (PU) was evaluated. A series of different cell lines, as well as freshly harvested animal cells, were grown on the PU surfaces with or without CBD-RGD, in serum or serum-free media. The results showed that the enhancement of cellular

Shan-hui Hsu; Wen-Ping Chu; Yu-Shuen Lin; Yu-Lin Chiang; David Chanhen Chen; Ching-Lin Tsai

2004-01-01

173

Genetic transfer of fusion proteins effectively inhibits VCAM-1-mediated cell adhesion and transmigration via inhibition of cytoskeletal anchorage.  

PubMed

The adhesion of leukocytes to endothelium plays a central role in the development of atherosclerosis and thus represents an attractive therapeutic target for anti-atherosclerotic therapies. Vascular cell adhesion molecule-1 (VCAM-1) mediates both the initial tethering and the firm adhesion of leukocytes to endothelial cells. Our work evaluates the feasibility of using the cytoskeletal anchorage of VCAM-1 as a target for gene therapy. As a proof of concept, integrin alphaIIbbeta3-mediated cell adhesion with clearly defined cytoskeletal anchorage was tested. We constructed fusion proteins containing the intracellular domain of beta3 placed at various distances to the cell membrane. Using cell adhesion assays and immunofluorescence, we established fusion constructs with competitive and dominant negative inhibition of cell adhesion. With the goal being the transfer of the dominant negative mechanism towards VCAM-1 inhibition, we constructed a fusion molecule containing the cytoplasmic domain of VCAM-1. Indeed, VCAM-1 mediated leukocyte adhesion can be inhibited via transfection of DNA encoding the designed VCAM-1 fusion protein. This is demonstrated in adhesion assays under static and flow conditions using CHO cells expressing recombinant VCAM-1 as well as activated endothelial cells. Thus, we are able to describe a novel approach for dominant negative inhibition of leukocyte adhesion to endothelial cells. This approach warrants further development as a novel gene therapeutic strategy that aims for a locally restricted effect at atherosclerotic areas of the vasculature. PMID:20414973

Hagemeyer, Christoph E; Ahrens, Ingo; Bassler, Nicole; Dschachutaschwili, Natia; Chen, Yung C; Eisenhardt, Steffen U; Bode, Christoph; Peter, Karlheinz

2010-01-01

174

Vitronectin is A Critical Protein Adhesion Substrate for IL-4-INDUCED Foreign Body Giant Cell Formation  

PubMed Central

An in vitro system of interleukin (IL)-4-induced foreign body giant cell (FBGC) formation was utilized to define the adhesion protein substrate(s) that promotes this aspect of the foreign body reaction on biomedical polymers. Human monocytes were cultured on cell culture polystyrene surfaces that had been pre-adsorbed with a synthetic arginine-glycine-aspartate (RGD) peptide previously found to support optimal FBGC formation, or with various concentrations of potential physiological protein substrates, i.e. complement C3bi, collagen types I or IV, fibrinogen, plasma fibronectin, fibroblast fibronectin, laminin, thrombospondin, vitronectin, or von Willebrand factor. Cultures were evaluated on days 0 (1.5 hr), 3, and 7 by May-Grünwald/Giemsa staining. Initial monocyte adhesion occurred on all adsorbed proteins. However, by day 7 of culture, only vitronectin was striking in its ability to support significant macrophage adhesion, development, and fusion leading to FBGC formation. Vitronectin supported high degrees of FBGC formation at an absorption concentration between 5 and 25 ?g per ml. These findings suggest that adsorbed vitronectin is critical in the collective events that support and promote FBGC formation on biomedical polymers, and that the propensity for vitronectin adsorption may underlie the material surface chemistry dependency of FBGC formation. PMID:17994558

McNally, Amy K.; Jones, Jacqueline A.; MacEwan, Sarah R.; Colton, Erica; Anderson, James M.

2014-01-01

175

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

176

pp125FAK a structurally distinctive protein-tyrosine kinase associated with focal adhesions.  

PubMed Central

Expression of the Rous sarcoma virus-encoded oncoprotein, pp60v-src, subverts the normal regulation of cell growth, which results in oncogenic transformation. This process requires the intrinsic protein-tyrosine kinase activity of pp60v-src and is associated with an increase in tyrosine phosphorylation of a number of cellular proteins, candidate substrates for pp60v-src. We report here the isolation of a cDNA encoding a protein, pp125, that is a major phosphotyrosine-containing protein in untransformed chicken embryo cells and exhibits an increase in phosphotyrosine in pp60v-src-transformed chicken embryo cells. This cDNA encodes a cytoplasmic protein-tyrosine kinase which, based upon its predicted amino acid sequence and structure, is the prototype for an additional family of protein-tyrosine kinases. Immunofluorescence localization experiments show that pp125 is localized to focal adhesions; hence, we suggest the name focal adhesion kinase. Images PMID:1594631

Schaller, M D; Borgman, C A; Cobb, B S; Vines, R R; Reynolds, A B; Parsons, J T

1992-01-01

177

Cellular localization and trafficking of vascular adhesion protein-1 as revealed by an N-terminal GFP fusion protein.  

PubMed

Recent studies of vascular adhesion protein-1 (VAP-1) have greatly advanced our understanding of the important role this protein plays in the establishment and progression of inflammatory disease. To facilitate more detailed studies on the function of VAP-1, we developed a GFP-fusion protein that enabled us to monitor the trafficking of the protein in three selected cell types: hepatic sinusoidal endothelial cells, liver myofibroblasts and an hepatic stellate cell line (LX-2). The fusion protein was detected as punctate cytoplasmic GFP staining, but was present only at low levels at the cell surface in all cell types studied. The subcellular distribution of the protein was not altered in a catalytically inactive mutant form of the protein (Tyr471Phe) or in the presence of exogenous VAP-1 substrate (methylamine) or inhibitor (semicarbazide). The GFP-VAP-1 protein was localized to the Golgi apparatus (GM-130), endoplasmic reticulum (GRP94) and early endosomes (EEA-1). Additional staining for VAP-1 revealed that the overexpressed protein was also present in vesicles that were negative for GFP fluorescent signal and did not express EEA-1. We propose that these vesicles are responsible for recycling the fusion protein and that the fluorescence of the GFP moiety is quenched at the low pH within these vesicles. This feature of the protein makes it well suited for live cell imaging studies where we wish to track protein that is being actively trafficked within the cell in preference to that which is being recycled. PMID:23474851

Weston, Chris J; Shepherd, Emma L; Adams, David H

2013-06-01

178

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

NASA Astrophysics Data System (ADS)

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

Brose, N.

179

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

PubMed Central

Background Protein expression profiles throughout 28 days of peripheral nerve regeneration were characterized using an established rat sciatic nerve transection injury model. Reverse phase protein microarrays were used to identify the spatial and temporal expression profile of multiple proteins implicated in peripheral nerve regeneration including growth factors, extracellular matrix proteins, and proteins involved in adhesion and migration. This high-throughput approach enabled the simultaneous analysis of 3,360 samples on a nitrocellulose-coated slide. Results The extracellular matrix proteins collagen I and III, laminin gamma-1, fibronectin, nidogen and versican displayed an early increase in protein levels in the guide and proximal sections of the regenerating nerve with levels at or above the baseline expression of intact nerve by the end of the 28 day experimental course. The 28 day protein levels were also at or above baseline in the distal segment however an early increase was only noted for laminin, nidogen, and fibronectin. While the level of epidermal growth factor, ciliary neurotrophic factor and fibroblast growth factor-1 and -2 increased throughout the experimental course in the proximal and distal segments, nerve growth factor only increased in the distal segment and fibroblast growth factor-1 and -2 and nerve growth factor were the only proteins in that group to show an early increase in the guide contents. As expected, several proteins involved in cell adhesion and motility; namely focal adhesion kinase, N-cadherin and ?-catenin increased earlier in the proximal and distal segments than in the guide contents reflecting the relatively acellular matrix of the early regenerate. Conclusions In this study we identified changes in expression of multiple proteins over time linked to regeneration of the rat sciatic nerve both demonstrating the utility of reverse phase protein arrays in nerve regeneration research and revealing a detailed, composite spatiotemporal expression profile of peripheral nerve regeneration. PMID:22325251

2012-01-01

180

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

Microsoft Academic Search

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

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

2009-01-01

181

Polymorphism of Submandibular-Sublingual Salivary Proteins which Promote Adhesion of Streptococcus mutans Serotype-c Strains to Hydroxyapatite  

Microsoft Academic Search

Previously, we showed that human submandibular-sublingual (SMSL) salivas contain one or more proteins, Mr circa 300,000 daltons, which specifically promote adhesion of Streptococcus mutans serotype-c strains to hydroxyapatite. Also, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the adhesion-promoting proteins (APPs) exhibit heterogeneity. The aims of the present study were to determine whether APPs are generally present in human

E. Kishimoto; D. I. Hay; R. Kent

1990-01-01

182

Processing of mussel-adhesive protein analog copolymer thin films by matrix-assisted pulsed laser evaporation  

NASA Astrophysics Data System (ADS)

We have demonstrated the successful thin film growth of a mussel-adhesive protein analog, DOPA-modified PEO-PPO-PEO block copolymer PF127, using matrix-assisted pulsed laser evaporation (MAPLE). The MAPLE-deposited thin films were examined using Fourier transform infrared spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and contact-angle measurements. We have found that the main functional groups of the mussel-adhesive protein analog are present in the transferred film. These adhesive materials have several potential electronic, medical, and marine applications.

Patz, T.; Cristescu, R.; Narayan, R.; Menegazzo, N.; Mizaikoff, B.; Messersmith, P. B.; Stamatin, I.; Mihailescu, I. N.; Chrisey, D. B.

2005-07-01

183

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

NASA Astrophysics Data System (ADS)

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

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

2009-09-01

184

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

PubMed Central

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

185

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

186

Fabricating surfaces with distinct geometries and different combinations of cell adhesion proteins.  

PubMed

A step-by-step procedure is described for functionalizing the surface of a glass coverslip so that a single cell contacts distinct patterns of extracellular matrix and cell-cell adhesion proteins. This dual-micropatterned substratum is accomplished through a two-step process. First, extracellular matrix (ECM) is microcontact-printed onto a silanized glass surface using electron beam lithography, etched resist-coated wafers, and Polydimethylsiloxane (PDMS) stamps of differing geometries. Then, non-ECM-coated surfaces are incubated sequentially with biotin, NeutrAvidin, and biotinylated Protein A to attach Fc-cadherin fusion proteins, Fc, or PEG. Cells are seeded at low density onto the functionalized surface for single-cell analysis of protein recruitment/turnover and cellular motility. PMID:23868591

Lowndes, Molly; Nelson, W James

2013-01-01

187

In Vivo Detection of Vascular Adhesion Protein-1 in Experimental Inflammation  

PubMed Central

Vascular adhesion protein-1 (VAP-1) is an inflammation-inducible endothelial glycoprotein which mediates leukocyte-endothelial cell interactions. To study the pathogenetic significance of VAP-1 in inflammatory disorders, an in vivo immunodetection method was used to detect the regulation of luminally expressed VAP-1 in experimental skin and joint inflammation in the pig and dog. Moreover, VAP-1 was studied as a potential target to localize inflammation by radioimmunoscintigraphy. Up-regulation of VAP-1 in experimental dermatitis and arthritis could be visualized by specifically targeted immunoscintigraphy. Moreover, the translocation of VAP-1 to the functional position on the endothelial surface was only seen in inflamed tissues. These results suggest that VAP-1 is both an optimal candidate for anti-adhesive therapy and a potential target molecule for imaging inflammation. PMID:10934150

Jaakkola, Kimmo; Nikula, Tuomo; Holopainen, Riikka; Vahasilta, Tommi; Matikainen, Marja-Terttu; Laukkanen, Marja-Leena; Huupponen, Risto; Halkola, Lauri; Nieminen, Lauri; Hiltunen, Jukka; Parviainen, Sakari; Clark, Michael R.; Knuuti, Juhani; Savunen, Timo; Kaapa, Pekka; Voipio-Pulkki, Liisa Maria; Jalkanen, Sirpa

2000-01-01

188

Nanotopographical Induction of Osteogenesis through Adhesion, Bone Morphogenic Protein Cosignaling, and Regulation of MicroRNAs.  

PubMed

It is emerging that nanotopographical information can be used to induce osteogenesis from mesenchymal stromal cells from the bone marrow, and it is hoped that this nanoscale bioactivity can be utilized to engineer next generation implants. However, the osteogenic mechanism of surfaces is currently poorly understood. In this report, we investigate mechanism and implicate bone morphogenic protein (BMP) in up-regulation of RUNX2 and show that RUNX2 and its regulatory miRNAs are BMP sensitive. Our data demonstrate that osteogenic nanotopography promotes colocalization of integrins and BMP2 receptors in order to enhance osteogenic activity and that vitronectin is important in this interface. This provides insight that topographical regulation of adhesion can have effects on signaling cascades outside of cytoskeletal signaling and that adhesions can have roles in augmenting BMP signaling. PMID:25227207

Yang, Jingli; McNamara, Laura E; Gadegaard, Nikolaj; Alakpa, Enateri V; Burgess, Karl V; Meek, R M Dominic; Dalby, Matthew J

2014-10-28

189

N-ethylmaleimide-sensitive factor attachment protein ? (?SNAP) regulates matrix adhesion and integrin processing in human epithelial cells.  

PubMed

Integrin-based adhesion to the extracellular matrix (ECM) plays critical roles in controlling differentiation, survival, and motility of epithelial cells. Cells attach to the ECM via dynamic structures called focal adhesions (FA). FA undergo constant remodeling mediated by vesicle trafficking and fusion. A soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein ? (?SNAP) is an essential mediator of membrane fusion; however, its roles in regulating ECM adhesion and cell motility remain unexplored. In this study, we found that siRNA-mediated knockdown of ?SNAP induced detachment of intestinal epithelial cells, whereas overexpression of ?SNAP increased ECM adhesion and inhibited cell invasion. Loss of ?SNAP impaired Golgi-dependent glycosylation and trafficking of ?1 integrin and decreased phosphorylation of focal adhesion kinase (FAK) and paxillin resulting in FA disassembly. These effects of ?SNAP depletion on ECM adhesion were independent of apoptosis and NSF. In agreement with our previous reports that Golgi fragmentation mediates cellular effects of ?SNAP knockdown, we found that either pharmacologic or genetic disruption of the Golgi recapitulated all the effects of ?SNAP depletion on ECM adhesion. Furthermore, our data implicates ?1 integrin, FAK, and paxillin in mediating the observed pro-adhesive effects of ?SNAP. These results reveal novel roles for ?SNAP in regulating ECM adhesion and motility of epithelial cells. PMID:24311785

Naydenov, Nayden G; Feygin, Alex; Wang, Lifu; Ivanov, Andrei I

2014-01-24

190

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

PubMed

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

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

2013-04-01

191

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

192

Developmentally dynamic colocalization patterns of DSCAM with adhesion and synaptic proteins in the mouse retina  

PubMed Central

Purpose The Down syndrome cell adhesion molecule (Dscam) gene is required for normal dendrite arborization and lamination in the mouse retina. In this study, we characterized the developmental localization of the DSCAM protein to better understand the postnatal stages of retinal development during which laminar disorganization occur in the absence of the protein. Methods Immunohistochemistry and colocalization analysis software were used to assay the localization of the DSCAM protein during development of the retina. Results We found that DSCAM was initially localized diffusely throughout mouse retinal neurites but then adopted a punctate distribution. DSCAM colocalized with catenins in the adult retina but was not detected at the active zone of chemical synapses, electrical synapses, and tight junctions. Further analysis identified a wave of colocalization between DSCAM and numerous synaptic and junction proteins coinciding with synaptogenesis between bipolar and retinal ganglion cells. Conclusions Research presented in this study expands our understanding of DSCAM function by characterizing its location during the development of the retina and identifies temporally regulated localization patterns as an important consideration in understanding the function of adhesion molecules in neural development.

Belem de Andrade, Gabriel; Kunzelman, Landon; Merrill, Morgan M.

2014-01-01

193

Secreted Listeria adhesion protein (Lap) influences Lap-mediated Listeria monocytogenes paracellular translocation through epithelial barrier  

PubMed Central

Background Listeria adhesion protein (Lap), an alcohol acetaldehyde dehydrogenase (lmo1634) promotes bacterial paracellular translocation through epithelial cell junctions during gastrointestinal phase of infection. Secreted Lap is critical for pathogenesis and is mediated by SecA2 system; however, if strain dependent variation in Lap secretion would affect L. monocytogenes paracellular translocation through epithelial barrier is unknown. Methods Amounts of Lap secretion were examined in clinical isolates of L. monocytogenes by cell fractionation analysis using Western blot. Quantitative reverse transcriptase PCR (qRT-PCR) was used to verify protein expression profiles. Adhesion and invasion of isolates were analyzed by in vitro Caco-2 cell culture model and paracellular translocation was determined using a trans-well model pre-seeded with Caco-2 cells. Results Western blot revealed that expression of Lap in whole cell preparation of isolates was very similar; however, cell fractionation analysis indicated variable Lap secretion among isolates. The strains showing high Lap secretion in supernatant exhibited significantly higher adhesion (3.4 - 4.8% vs 1.5 - 2.3%, P?protein transport system, SecA2. ?secA2 mutants showed significantly reduced paracellular translocation through epithelial barrier (0.48?±?0.01 vs 0.24?±?0.02, P?

2013-01-01

194

Plakophilin 2 Affects Cell Migration by Modulating Focal Adhesion Dynamics and Integrin Protein Expression  

PubMed Central

Plakophilin 2 (PKP2), a desmosome component, modulates the activity and localization of the small GTPase RhoA at sites of cell–cell contact. PKP2 regulates cortical actin rearrangement during junction formation, and its loss is accompanied by an increase in actin stress fibers. We hypothesized that PKP2 may regulate focal adhesion dynamics and cell migration. Here we show that PKP2-deficient cells bind efficiently to the extracellular matrix, but upon spreading display total cell areas ~30% smaller than control cells. Focal adhesions in PKP2-deficient cells are ~2× larger and more stable than in control cells, and vinculin displays an increased time for fluorescence recovery after photobleaching. Furthermore, ?4 and ?1 integrin protein and mRNA expression is elevated in PKP2-silenced cells. Normal focal adhesion phenotypes can be restored in PKP2-null cells by dampening the RhoA pathway or silencing ?1 integrin. However, integrin expression levels are not restored by RhoA signaling inhibition. These data uncover a potential role for PKP2 upstream of ?1 integrin and RhoA in integrating cell–cell and cell–substrate contact signaling in basal keratinocytes necessary for the morphogenesis, homeostasis, and reepithelialization of the stratified epidermis. PMID:23884246

Koetsier, Jennifer L.; Amargo, Evangeline V.; Todorovic, Viktor; Green, Kathleen J.; Godsel, Lisa M.

2014-01-01

195

Nanometer polymer surface features: the influence on surface energy, protein adsorption and endothelial cell adhesion  

NASA Astrophysics Data System (ADS)

Current small diameter (<5 mm) synthetic vascular graft materials exhibit poor long-term patency due to thrombosis and intimal hyperplasia. Tissue engineered solutions have yielded functional vascular tissue, but some require an eight-week in vitro culture period prior to implantation—too long for immediate clinical bedside applications. Previous in vitro studies have shown that nanostructured poly(lactic-co-glycolic acid) (PLGA) surfaces elevated endothelial cell adhesion, proliferation, and extracellular matrix synthesis when compared to nanosmooth surfaces. Nonetheless, these studies failed to address the importance of lateral and vertical surface feature dimensionality coupled with surface free energy; nor did such studies elicit an optimum specific surface feature size for promoting endothelial cell adhesion. In this study, a series of highly ordered nanometer to submicron structured PLGA surfaces of identical chemistry were created using a technique employing polystyrene nanobeads and poly(dimethylsiloxane) (PDMS) molds. Results demonstrated increased endothelial cell adhesion on PLGA surfaces with vertical surface features of size less than 18.87 nm but greater than 0 nm due to increased surface energy and subsequently protein (fibronectin and collagen type IV) adsorption. Furthermore, this study provided evidence that the vertical dimension of nanometer surface features, rather than the lateral dimension, is largely responsible for these increases. In this manner, this study provides key design parameters that may promote vascular graft efficacy.

Carpenter, Joseph; Khang, Dongwoo; Webster, Thomas J.

2008-12-01

196

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

197

High-speed atomic force microscopy: cooperative adhesion and dynamic equilibrium of junctional microdomain membrane proteins.  

PubMed

Junctional microdomains, paradigm for membrane protein segregation in functional assemblies, in eye lens fiber cell membranes are constituted of lens-specific aquaporin-0 tetramers (AQP0(4)) and connexin (Cx) hexamers, termed connexons. Both proteins have double function to assure nutrition and mediate adhesion of lens cells. Here we use high-speed atomic force microscopy to examine microdomain protein dynamics at the single-molecule level. We found that the adhesion function of head-to-head associated AQP0(4) and Cx is cooperative. This finding provides first experimental evidence for the mechanistic importance for junctional microdomain formation. From the observation of lateral association-dissociation events of AQP0(4), we determine that the enthalpic energy gain of a single AQP0(4)-AQP0(4) interaction in the membrane plane is -2.7 k(B)T, sufficient to drive formation of microdomains. Connexon association is stronger as dynamics are rarely observed, explaining their rim localization in junctional microdomains. PMID:22796628

Colom, Adai; Casuso, Ignacio; Boudier, Thomas; Scheuring, Simon

2012-10-19

198

The effect of surface microtopography of poly(dimethylsiloxane) on protein adsorption, platelet and cell adhesion.  

PubMed

Chemical homogeneous poly(dimethylsiloxane) (PDMS) surface with dot-like protrusion pattern was used to investigate the individual effect of surface microtopography on protein adsorption and subsequent biological responses. Fibrinogen (Fg) and fibronectin (Fn) were chosen as model proteins due to their effect on platelet and cell adhesion, respectively. Fg labeled with (125)I and fluorescein isothiocyanate (FITC) was used to study its adsorption on flat and patterned surfaces. Patterned surface has a 46% increase in the adsorption of Fg when compared with flat surface. However, the surface area of the patterned surface was only 8% larger than that of the flat surface. Therefore, the increase in the surface area was not the only factor responsible for the increase in protein adsorption. Clear fluorescent pattern was visualized on patterned surface, indicating that adsorbed Fg regularly distributed and adsorbed most on the flanks and valleys of the protrusions. Such distribution and local enrichment of Fg presumably caused the specific location of platelets adhered from platelet-rich plasma (PRP) and flowing whole blood (FWB) on patterned surface. Furthermore, the different combination of surface topography and pre-adsorbed Fn could influence the adhesion of L929 cells. The flat surface with pre-adsorbed Fn was the optimum substrate while the virgin patterned surface was the poor substrate in terms of L929 cells spread. PMID:19303747

Chen, Hong; Song, Wei; Zhou, Feng; Wu, Zhongkui; Huang, He; Zhang, Junhu; Lin, Quan; Yang, Bai

2009-07-01

199

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

200

The cell–cell adhesion molecule EpCAM interacts directly with the tight junction protein claudin-7  

Microsoft Academic Search

We recently described that in the metastasizing rat pancreatic carcinoma line BSp73ASML the cell–cell adhesion molecule EpCAM, CD44 variant isoforms and the tetraspanins D6.1A and CD9 form a complex that is located in glycolipid-enriched membrane microdomains. This complex contains, in addition, an undefined 20 kDa protein. As such complex formation influenced cell–cell adhesion and apoptosis resistance, it became of interest

Markus Ladwein; Ulrich-Frank Pape; Dirk-Steffen Schmidt; Martina Schnölzer; Sabine Fiedler; Lutz Langbein; Werner W. Franke; Gerhard Moldenhauer; Margot Zöller

2005-01-01

201

Control of supramolecular chirality of nanofibers and its effect on protein adhesion.  

PubMed

Chiral nanostructure, such as the double helix of DNA and ?-helix of protein, plays an important role in biochemistry and material sciences. In the organism system, the biological entities always exhibit homochirality and show preference toward one specific enantiomer. How the opposite enantiomers will affect the chirality of the supramolecular nanostructures and their interactions with the biological molecules remains an important issue. In this study, two gelators bearing amphiphilic l-glutamide and d- or l-pantolactone (abbreviated as DPLG and LPLG) were designed, and their self-assembly behavior and interactions with proteins were investigated. It was found that both of the gelators could form gels in the mixed solvent of ethanol and water, and the corresponding gels were characterized with UV-vis spectroscopy, circular dichroism, Fourier transform infrared spectroscopy, X-ray diffraction, and atomic force microscopy. Although both gels formed nanofiber structures and showed many similar properties, their supramolecular chiralities were opposite, which was determined by the chirality of the terminal group. The chirality of the nanofibrous structure is found to influence the protein adhesion significantly. Quartz crystal microbalance technique was used to investigate the adsorption of human serum albumin on the nanofibrous structures. It was revealed that supramolecular nanostructure of DPLG exhibited stronger adhesive ability than that of LPLG, while there is no clear difference at a molecular level. This suggested that slightly different interactions between d and l substances with the biological molecules could be amplified when they formed chiral nanostructures. Molecular dynamic simulations were performed to verify the interaction between the two gelators and protein molecules. A possible model was proposed to explain the interaction between the nanofibers and the proteins. PMID:25302778

Lv, Kai; Zhang, Li; Lu, Wensheng; Liu, Minghua

2014-11-12

202

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

203

Protein-Mediated Adhesion of the Dissimilatory Fe(III)-Reducing Bacterium Shewanella alga BrY to Hydrous Ferric Oxide  

PubMed Central

The rate and extent of bacterial Fe(III) mineral reduction are governed by molecular-scale interactions between the bacterial cell surface and the mineral surface. These interactions are poorly understood. This study examined the role of surface proteins in the adhesion of Shewanella alga BrY to hydrous ferric oxide (HFO). Enzymatic degradation of cell surface polysaccharides had no effect on cell adhesion to HFO. The proteolytic enzymes Streptomyces griseus protease and chymotrypsin inhibited the adhesion of S. alga BrY cells to HFO through catalytic degradation of surface proteins. Trypsin inhibited S. alga BrY adhesion solely through surface-coating effects. Protease and chymotrypsin also mediated desorption of adhered S. alga BrY cells from HFO while trypsin did not mediate cell desorption. Protease removed a single peptide band that represented a protein with an apparent molecular mass of 50 kDa. Chymotrypsin removed two peptide bands that represented proteins with apparent molecular masses of 60 and 31 kDa. These proteins represent putative HFO adhesion molecules. S. alga BrY adhesion was inhibited by up to 46% when cells were cultured at sub-MICs of chloramphenicol, suggesting that protein synthesis is necessary for adhesion. Proteins extracted from the surface of S. alga BrY cells inhibited adhesion to HFO by up to 41%. A number of these proteins bound specifically to HFO, suggesting that a complex system of surface proteins mediates S. alga BrY adhesion to HFO. PMID:10543817

Caccavo, Frank

1999-01-01

204

Viability and proliferation of rat MSCs on adhesion protein-modified PET and PU scaffolds.  

PubMed

In 2011, the first in-man successful transplantation of a tissue engineered trachea-bronchial graft, using a synthetic POSS-PCU nanocomposite construct seeded with autologous stem cells, was performed. To further improve this technology, we investigated the feasibility of using polymers with a three dimensional structure more closely mimicking the morphology and size scale of native extracellular matrix (ECM) fibers. We therefore investigated the in vitro biocompatibility of electrospun polyethylene terephthalate (PET) and polyurethane (PU) scaffolds, and determined the effects on cell attachment by conditioning the fibers with adhesion proteins. Rat mesenchymal stromal cells (MSCs) were seeded on either PET or PU fiber-layered culture plates coated with laminin, collagen I, fibronectin, poly-D-lysine or gelatin. Cell density, proliferation, viability, morphology and mRNA expression were evaluated. MSC cultures on PET and PU resulted in similar cell densities and amounts of proliferating cells, with retained MSC phenotype compared to data obtained from tissue culture plate cultures. Coating the scaffolds with adhesion proteins did not increase cell density or cell proliferation. Our data suggest that both PET and PU mats, matching the dimensions of ECM fibers, are biomimetic scaffolds and, because of their high surface area-to-volume provided by the electrospinning procedure, makes them per se suitable for cell attachment and proliferation without any additional coating. PMID:22901964

Gustafsson, Ylva; Haag, Johannes; Jungebluth, Philipp; Lundin, Vanessa; Lim, Mei Ling; Baiguera, Silvia; Ajalloueian, Fatemeh; Del Gaudio, Costantino; Bianco, Alessandra; Moll, Guido; Sjöqvist, Sebastian; Lemon, Greg; Teixeira, Ana Isabel; Macchiarini, Paolo

2012-11-01

205

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

206

Inhibition of fibroblast adhesion by covalently immobilized protein repellent polymer coatings studied by single cell force spectroscopy.  

PubMed

Cochlea implants (CI) restore the hearing in patients with sensorineural hearing loss by electrical stimulation of the auditory nerve via an electrode array. The increase of the impedance at the electrode-tissue interface due to a postoperative connective tissue encapsulation leads to higher power consumption of the implants. Therefore, reduced adhesion and proliferation of connective tissue cells around the CI electrode array is of great clinical interest. The adhesion of cells to substrate surfaces is mediated by extracellular matrix (ECM) proteins. Protein repellent polymers (PRP) are able to inhibit unspecific protein adsorption. Thus, a reduction of cell adhesion might be achieved by coating the electrode carriers with PRPs. The aim of this study was to investigate the effects of two different PRPs, poly(dimethylacrylamide) (PDMAA) and poly(2-ethyloxazoline) (PEtOx), on the strength and the temporal dynamics of the initial adhesion of fibroblasts. Polymers were immobilized onto glass plates by a photochemical grafting onto method. Water contact angle measurements proved hydrophilic surface properties of both PDMAA and PEtOx (45 ± 1° and 44 ± 1°, respectively). The adhesion strength of NIH3T3 fibroblasts after 5, 30, and 180 s of interaction with surfaces was investigated by using single cell force spectroscopy. In comparison to glass surfaces, both polymers reduced the adhesion of fibroblasts significantly at all different interaction times and lower dynamic rates of adhesion were observed. Thus, both PDMAA and PEtOx represented antiadhesive properties and can be used as implant coatings to reduce the unspecific ECM-mediated adhesion of fibroblasts to surfaces. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013. PMID:23596088

Aliuos, Pooyan; Sen, Aromita; Reich, Uta; Dempwolf, Wibke; Warnecke, Athanasia; Hadler, Christoph; Lenarz, Thomas; Menzel, Henning; Reuter, Guenter

2013-04-18

207

Expression of fibronectin-binding protein FbpA modulates adhesion in Streptococcus gordonii.  

PubMed

Fibronectin binding is considered to be an important virulence factor in streptococcal infections. Adhesion of the oral bacterium Streptococcus gordonii to immobilized forms of fibronectin is mediated, in part, by a high molecular mass wall-anchored protein designated CshA. In this study, a second fibronectin-binding protein of S. gordonii is described that has been designated as FbpA (62.7 kDa). This protein, which is encoded by a gene located immediately downstream of the cshA gene, shows 85 and 81% identity to the fibronectin-binding proteins PavA, of Streptococcus pneumoniae, and FBP54, of Streptococcus pyogenes, respectively. Purified recombinant FbpA bound to immobilized human fibronectin in a dose-dependant manner, and isogenic mutants in which the fbpA gene was inactivated were impaired in their binding to fibronectin. This effect was apparent only for cells in the exponential phase of growth, and was associated with reduced surface hydrophobicity and the surface expression of CshA. Cells in the stationary phase of growth were unaffected in their ability to bind to fibronectin. By utilizing gene promoter fusions with cat (encoding chloramphenicol O-acetyltransferase), it was demonstrated that cshA expression was down-regulated during the exponential phase of growth in the fbpA mutant. Expression of fbpA, but not cshA, was sensitive to atmospheric O2 levels, and was found to be up-regulated in the presence of elevated O2 levels. The results suggest that FbpA plays a regulatory role in the modulation of CshA expression and, thus, affects the adhesion of S. gordonii to fibronectin. PMID:12055283

Christie, Julie; McNab, Roderick; Jenkinson, Howard F

2002-06-01

208

Major Membrane Protein TDE2508 Regulates Adhesive Potency in Treponema denticola  

PubMed Central

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

209

A standardized bamboo leaf extract inhibits monocyte adhesion to endothelial cells by modulating vascular cell adhesion protein-1  

PubMed Central

Bamboo leaves (Phyllostachys pubescens Mazel ex J. Houz (Poacea)) have a long history of food and medical applications in Asia, including Japan and Korea. They have been used as a traditional medicine for centuries. We investigated the mechanism of anti-inflammatory activity of a bamboo leaf extract (BLE) on tumor necrosis factor-alpha (TNF-?)-induced monocyte adhesion in human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs to BLE did not inhibit cell viability or cause morphological changes at concentrations ranging from 1 µg/ml to 1 mg/ml. Treatment with 0.1 mg/ml BLE caused 63% inhibition of monocyte adhesion in TNF-?-activated HUVECs, which was associated with 38.4% suppression of vascular cell adhesion molecule-1 expression. Furthermore, TNF-?-induced reactive oxygen species generation was decreased to 47.9% in BLE treated TNF-?-activated HUVECs. BLE (0.05 mg/ml) also caused about 50% inhibition of interleukin-6 secretion from lipopolysaccharide-stimulated monocyte. The results indicate that BLE may be clinically useful as an anti-inflammatory or anti-oxidant for human cardiovascular disease including atherosclerosis. PMID:23422838

Choi, Sunga; Park, Myoung Soo; Lee, Yu Ran; Lee, Young Chul; Kim, Tae Woo; Do, Seon-Gil; Kim, Dong Seon

2013-01-01

210

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

PubMed

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

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

2013-01-01

211

Unraveling the Role of Surface Mucus-Binding Protein and Pili in Muco-Adhesion of Lactococcus lactis  

PubMed Central

Adhesion of bacteria to mucus may favor their persistence within the gut and their beneficial effects to the host. Interactions between pig gastric mucin (PGM) and a natural isolate of Lactococcus lactis (TIL448) were measured at the single-cell scale and under static conditions, using atomic force microscopy (AFM). In parallel, these interactions were monitored at the bacterial population level and under shear flow. AFM experiments with a L. lactis cell-probe and a PGM-coated surface revealed a high proportion of specific adhesive events (60%) and a low level of non-adhesive ones (2%). The strain muco-adhesive properties were confirmed by the weak detachment of bacteria from the PGM-coated surface under shear flow. In AFM, rupture events were detected at short (100?200 nm) and long distances (up to 600?800 nm). AFM measurements on pili and mucus-binding protein defective mutants demonstrated the comparable role played by these two surface proteinaceous components in adhesion to PGM under static conditions. Under shear flow, a more important contribution of the mucus-binding protein than the pili one was observed. Both methods differ by the way of probing the adhesion force, i.e. negative force contact vs. sedimentation and normal-to-substratum retraction vs. tangential detachment conditions, using AFM and flow chamber, respectively. AFM blocking assays with free PGM or O-glycan fractions purified from PGM demonstrated that neutral oligosaccharides played a major role in adhesion of L. lactis TIL448 to PGM. This study dissects L. lactis muco-adhesive phenotype, in relation with the nature of the bacterial surface determinants. PMID:24260308

Duviau, Marie-Pierre; Meyrand, Mickael; Guerardel, Yann; Castelain, Mickael; Loubiere, Pascal; Chapot-Chartier, Marie-Pierre; Dague, Etienne; Mercier-Bonin, Muriel

2013-01-01

212

Bidirectional integrin alphaIIbbeta3 signalling regulating platelet adhesion under flow: contribution of protein kinase C.  

PubMed Central

Platelet adhesion on von Willebrand factor (vWf) requires the co-ordinated adhesive function of glycoprotein Ib/V/IX and integrin alphaIIbbeta3. Recent evidence [Nesbitt, Kulkarni, Giuliano, Gonclaves, Dopheide, Yap, Harper, Salem and Jackson (2002) J. Biol. Chem. 277, 2965-2972] suggests that outside-in signals from both receptors play important roles in regulating platelet-adhesion dynamics under flow. In the present study, we have examined the mechanisms utilized by protein kinase C (PKC) to promote irreversible platelet adhesion on vWf. We demonstrate that PKC is primarily activated downstream of integrin alphaIIbbeta3, not glycoprotein Ib, during platelet adhesion on vWf. This integrin alphaIIbbeta3-dependent PKC activation establishes a positive-feedback loop that promotes further integrin alphaIIbbeta3 activation, calcium mobilization and firm platelet adhesion. This feedback loop appears to be most relevant at relatively low cytosolic calcium concentrations (mean Delta[Ca(2+)](i);100 nM) as artificially elevating calcium (mean Delta[Ca(2+)](i) > 500 nM) induces integrin alphaIIbbeta3 activation and irreversible platelet adhesion independent of PKC. Our studies demonstrate the existence of a complex signalling relationship operating between PKC, cytosolic calcium and integrin alphaIIbbeta3 that serves to regulate platelet-adhesion dynamics under flow. Furthermore, we have established the existence of PKC-dependent and -independent pathways regulating integrin alphaIIbbeta3 activation and stable platelet adhesion on vWf. PMID:12585966

Giuliano, Simon; Nesbitt, Warwick S; Rooney, Michael; Jackson, Shaun P

2003-01-01

213

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

PubMed Central

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

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

2013-01-01

214

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

215

Photochemically immobilized polymer coatings: effects on protein adsorption, cell adhesion, and leukocyte activation.  

PubMed

Amphiphilic chains of 4-benzoylbenzoic acid moieties and polymer were photochemically immobilized onto silicone rubber to ask whether the covalently coupled polymers would passivate the silicone rubber by inhibiting protein adsorption and subsequent cell adhesion and activation. Three groups of polymers were utilized: the hydrophilic synthetic polymers of polyacrylamide, polyethylene glycol, and polyvinylpyrrolidone; the glycosaminoglycan, hyaluronic acid; and poly(glycine-valine-glycine-valine-proline), a polypeptide derived from the sequence of elastin. Each coating variant decreased the adsorption of fibrinogen and immunoglobulin G compared to uncoated silicone rubber. All except the methoxy-polyethylene glycol coating nearly abolished fibroblast growth, but none of the coating variants inhibited monocyte or polymorphonuclear leukocyte adhesion. Interleukin-1beta, interleukin-1 receptor antagonist, and tumor necrosis factor-alpha secretion by leukocytes were not statistically different between any of the coating variants and uncoated silicone rubber. However, the methoxy-polyethylene glycol and elastin-based polypeptide coatings, which supported the highest numbers of adherent monocytes, also elicited the lowest levels of proinflammatory cytokine secretion. When these in vitro data were collectively evaluated, the coating that most effectively passivated silicone rubber was the polypeptide derived from elastin. PMID:10591132

Defife, K M; Hagen, K M; Clapper, D L; Anderson, J M

1999-01-01

216

Pharmacologic blockade of vascular adhesion protein-1 lessens neurologic dysfunction in rats subjected to subarachnoid hemorrhage.  

PubMed

Aneurysmal subarachnoid hemorrhage (SAH) is a potentially devastating clinical problem. Despite advances in the diagnosis and treatment of SAH, outcome remains unfavorable. An increased inflammatory state, one that is characterized by enhanced leukocyte trafficking has been reported to contribute to neuronal injury in association with multiple brain insults, including hemorrhagic and ischemic stroke. This study was designed to investigate, in rats, the neuropathologic consequences of heightened leukocyte trafficking following SAH, induced via endovascular perforation of the anterior cerebral artery. Experiments focused on the initial 48h post-SAH and sought to establish whether blockade of vascular adhesion protein-1 (VAP-1), with LJP-1586, was able to provide dose-dependent neuroprotection. Treatment with LJP-1586 was initiated at 6h post-SAH. An intravital microscopy and closed cranial window system, that permitted examination of temporal patterns of rhodamine-6G-labeled leukocyte adhesion/extravasation, was used. Effects of LJP-1586 on neurologic outcomes and leukocyte trafficking at 24h and 48h post-SAH were examined. In VAP-1-inhibited vs control rats, results revealed a significant attenuation in leukocyte trafficking at both 24h and 48h after SAH, along with an improvement in neurologic outcome. In conclusion, our findings support the involvement of an amplified inflammatory state, characterized by enhanced leukocyte trafficking, during the first 48h after SAH. VAP-1 blockade yielded neuroprotection that was associated with an attenuation of leukocyte trafficking and improved neurologic outcome. PMID:25175836

Xu, Hao-Liang; Garcia, Maggie; Testai, Fernando; Vetri, Francesco; Barabanova, Alexandra; Pelligrino, Dale A; Paisansathan, Chanannait

2014-10-24

217

Anterior Gradient Protein-2 Is a Regulator of Cellular Adhesion in Prostate Cancer  

PubMed Central

Anterior Gradient Protein (AGR-2) is reported to be over-expressed in many epithelial cancers and promotes metastasis. A clear-cut mechanism for its observed function(s) has not been previously identified. We found significant upregulation of AGR-2 expression in a bone metastatic prostate cancer cell line, PC3, following culturing in bone marrow-conditioned medium. Substantial AGR-2 expression was also confirmed in prostate cancer tissue specimens in patients with bone lesions. By developing stable clones of PC3 cells with varying levels of AGR-2 expression, we identified that abrogation of AGR-2 significantly reduced cellular attachment to fibronectin, collagen I, collagen IV, laminin I and fibrinogen. Loss of cellular adhesion was associated with sharp decrease in the expression of ?4, ?5, ?V, ?3 and ?4 integrins. Failure to undergo apoptosis following detachment is a hallmark of epithelial cancer metastasis. The AGR-2-silenced PC3 cells showed higher resistance to Tumor necrosis factor-related apoptosis- inducing ligand (TRAIL) induced apoptosis in vitro. This observation was also supported by significantly reduced Caspase-3 expression in AGR-2-silenced PC3 cells, which is a key effector of both extrinsic and intrinsic death signaling pathways. These data suggest that AGR-2 influence prostate cancer metastasis by regulation of cellular adhesion and apoptosis. PMID:24587138

Chanda, Diptiman; Lee, Joo Hyoung; Sawant, Anandi; Hensel, Jonathan A.; Isayeva, Tatyana; Reilly, Stephanie D.; Siegal, Gene P.; Smith, Claire; Grizzle, William; Singh, Raj; Ponnazhagan, Selvarangan

2014-01-01

218

Syntenin-1 and ezrin proteins link activated leukocyte cell adhesion molecule to the actin cytoskeleton.  

PubMed

Activated leukocyte cell adhesion molecule (ALCAM) is a type I transmembrane protein member of the immunoglobulin superfamily of cell adhesion molecules. Involved in important pathophysiological processes such as the immune response, cancer metastasis, and neuronal development, ALCAM undergoes both homotypic interactions with other ALCAM molecules and heterotypic interactions with the surface receptor CD6 expressed at the T cell surface. Despite biochemical and biophysical evidence of a dynamic association between ALCAM and the actin cytoskeleton, no detailed information is available about how this association occurs at the molecular level. Here, we exploit a combination of complementary microscopy techniques, including FRET detected by fluorescence lifetime imaging microscopy and single-cell force spectroscopy, and we demonstrate the existence of a preformed ligand-independent supramolecular complex where ALCAM stably interacts with actin by binding to syntenin-1 and ezrin. Interaction with the ligand CD6 further enhances these multiple interactions. Altogether, our results propose a novel biophysical framework to understand the stabilizing role of the ALCAM supramolecular complex engaged to CD6 during dendritic cell-T cell interactions and provide novel information on the molecular players involved in the formation and signaling of the immunological synapse at the dendritic cell side. PMID:24662291

Tudor, Cicerone; te Riet, Joost; Eich, Christina; Harkes, Rolf; Smisdom, Nick; Bouhuijzen Wenger, Jessica; Ameloot, Marcel; Holt, Matthew; Kanger, Johannes S; Figdor, Carl G; Cambi, Alessandra; Subramaniam, Vinod

2014-05-01

219

Photorhabdus adhesion modification protein (Pam) binds extracellular polysaccharide and alters bacterial attachment  

PubMed Central

Background Photorhabdus are Gram-negative nematode-symbiotic and insect-pathogenic bacteria. The species Photorhabdus asymbiotica is able to infect humans as well as insects. We investigated the secreted proteome of a clinical isolate of P. asymbiotica at different temperatures in order to identify proteins relevant to the infection of the two different hosts. Results A comparison of the proteins secreted by a clinical isolate of P. asymbiotica at simulated insect (28°C) and human (37°C) temperatures led to the identification of a small and highly abundant protein, designated Pam, that is only secreted at the lower temperature. The pam gene is present in all Photorhabdus strains tested and shows a high level of conservation across the whole genus, suggesting it is both ancestral to the genus and probably important to the biology of the bacterium. The Pam protein shows limited sequence similarity to the 13.6 kDa component of a binary toxin of Bacillus thuringiensis. Nevertheless, injection or feeding of heterologously produced Pam showed no insecticidal activity to either Galleria mellonella or Manduca sexta larvae. In bacterial colonies, Pam is associated with an extracellular polysaccharide (EPS)-like matrix, and modifies the ability of wild-type cells to attach to an artificial surface. Interestingly, Surface Plasmon Resonance (SPR) binding studies revealed that the Pam protein itself has adhesive properties. Although Pam is produced throughout insect infection, genetic knockout does not affect either insect virulence or the ability of P. luminescens to form a symbiotic association with its host nematode, Heterorhabditis bacteriophora. Conclusions We studied a highly abundant protein, Pam, which is secreted in a temperature-dependent manner in P. asymbiotica. Our findings indicate that Pam plays an important role in enhancing surface attachment in insect blood. Its association with exopolysaccharide suggests it may exert its effect through mediation of EPS properties. Despite its abundance and conservation in the genus, we find no evidence for a role of Pam in either virulence or symbiosis. PMID:20462430

2010-01-01

220

Catechol-functionalized adhesive polymer nanoparticles for controlled local release of bone morphogenetic protein-2 from titanium surface.  

PubMed

We report on a novel surface functionalization approach to equip the titanium (Ti) surfaces with osteogenic properties. A key feature of the approach is the treatment of the Ti surfaces with Ti-adhesive nanoparticles that can stably load and controllably release bone morphogenetic protein-2 (BMP-2). Ti-adhesive nanoparticles were prepared by self-assembly of a catechol-functionalized poly(amino acid) diblock copolymer, catechol-poly(L-aspartic acid)-b-poly(L-phenylalanine) (Cat-PAsp-PPhe). The nanoparticles consist of Ti-adhesive peripheral catechol groups, anionic PAsp shells, and PPhe inner cores. Field-emission scanning electron microscopy (Fe-SEM) images showed that the Ti-adhesive nanoparticles could be uniformly immobilized on Ti surfaces. X-ray photoelectron spectroscopy (XPS) confirmed the successful anchoring of nanoparticles onto Ti surfaces. After surface immobilization of the nanoparticles, the static water contact angle of the Ti substrate decreased from 75.3° to 50.0° or 36.4°, depending on the surface nanoparticle. Fluorescence microscopic analysis showed that BMP-2 could be effectively incorporated onto the Ti surface with adhesive nanoparticles. BMP-2 was controllably released for up to 40 days. The Ti substrate functionalized with BMP-2-incorporated nanoparticles significantly promoted attachment, proliferation, spreading, and alkaline phosphatase (ALP) activity of human adipose-derived stem cell (hADSC). The catechol-functionalized adhesive nanoparticles may be applied to various medical devices to create surfaces for improved performance. PMID:23727196

Lee, Hong Jae; Koo, Ahn Na; Lee, Suk Won; Lee, Myung Hyun; Lee, Sang Cheon

2013-09-10

221

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

PubMed

Cell migration is a complex process that requires the integration of signaling events that occur in distinct locations within the cell. Adaptor proteins, which can localize to different subcellular compartments, where they bring together key signaling proteins, are emerging as attractive candidates for controlling spatially coordinated processes. However, their function in regulating cell migration is not well understood. In this study, we demonstrate a novel role for the adaptor protein containing a pleckstrin-homology (PH) domain, phosphotyrosine-binding (PTB) domain, and leucine zipper motif 1 (APPL1) in regulating cell migration. APPL1 impairs migration by hindering the turnover of adhesions at the leading edge of cells. The mechanism by which APPL1 regulates migration and adhesion dynamics is by inhibiting the activity of the serine/threonine kinase Akt at the cell edge and within adhesions. In addition, APPL1 significantly decreases the tyrosine phosphorylation of Akt by the nonreceptor tyrosine kinase Src, which is critical for Akt-mediated cell migration. Thus, our results demonstrate an important new function for APPL1 in regulating cell migration and adhesion turnover through a mechanism that depends on Src and Akt. Moreover, our data further underscore the importance of adaptor proteins in modulating the flow of information through signaling pathways. PMID:22379109

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

2012-04-01

222

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

PubMed Central

Cell migration is a complex process that requires the integration of signaling events that occur in distinct locations within the cell. Adaptor proteins, which can localize to different subcellular compartments, where they bring together key signaling proteins, are emerging as attractive candidates for controlling spatially coordinated processes. However, their function in regulating cell migration is not well understood. In this study, we demonstrate a novel role for the adaptor protein containing a pleckstrin-homology (PH) domain, phosphotyrosine-binding (PTB) domain, and leucine zipper motif 1 (APPL1) in regulating cell migration. APPL1 impairs migration by hindering the turnover of adhesions at the leading edge of cells. The mechanism by which APPL1 regulates migration and adhesion dynamics is by inhibiting the activity of the serine/threonine kinase Akt at the cell edge and within adhesions. In addition, APPL1 significantly decreases the tyrosine phosphorylation of Akt by the nonreceptor tyrosine kinase Src, which is critical for Akt-mediated cell migration. Thus, our results demonstrate an important new function for APPL1 in regulating cell migration and adhesion turnover through a mechanism that depends on Src and Akt. Moreover, our data further underscore the importance of adaptor proteins in modulating the flow of information through signaling pathways. PMID:22379109

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

2012-01-01

223

Pathogenic Naegleria fowleri and non-pathogenic Naegleria lovaniensis exhibit differential adhesion to, and invasion of, extracellular matrix proteins.  

PubMed

Naegleria fowleri and Naegleria lovaniensis are closely related free-living amoebae found in the environment. N. fowleri causes primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system, while N. lovaniensis is non-pathogenic. N. fowleri infection occurs when the amoebae access the nasal passages, attach to the nasal mucosa and its epithelial lining, and migrate to the brain. This process involves interaction with components of the host extracellular matrix (ECM). Since the ability to invade tissues can be a characteristic that distinguishes pathogenic from non-pathogenic amoebae, the objective of this study was to assess adhesion to, and invasion of, the ECM by these two related but distinct Naegleria species. N. fowleri exhibited a higher level of adhesion to the ECM components laminin-1, fibronectin and collagen I. Scanning electron microscopy revealed that N. fowleri attached on ECM substrata exhibited a spread-out appearance that included the presence of focal adhesion-like structures. Western immunoblotting revealed two integrin-like proteins for both species, but one of these, with a molecular mass of approximately 70 kDa, was detected at a higher level in N. fowleri. Confocal microscopy indicated that the integrin-like proteins co-localized to the focal adhesion-like structures. Furthermore, anti-integrin antibody decreased adhesion of N. fowleri to ECM components. Finally, N. fowleri disrupted 3D ECM scaffolds, while N. lovaniensis had a minimal effect. Collectively, these results indicate a distinction in adhesion to, and invasion of, ECM proteins between N. fowleri and N. lovaniensis. PMID:22222499

Jamerson, Melissa; da Rocha-Azevedo, Bruno; Cabral, Guy A; Marciano-Cabral, Francine

2012-03-01

224

Pathogenic Naegleria fowleri and non-pathogenic Naegleria lovaniensis exhibit differential adhesion to, and invasion of, extracellular matrix proteins  

PubMed Central

Naegleria fowleri and Naegleria lovaniensis are closely related free-living amoebae found in the environment. N. fowleri causes primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system, while N. lovaniensis is non-pathogenic. N. fowleri infection occurs when the amoebae access the nasal passages, attach to the nasal mucosa and its epithelial lining, and migrate to the brain. This process involves interaction with components of the host extracellular matrix (ECM). Since the ability to invade tissues can be a characteristic that distinguishes pathogenic from non-pathogenic amoebae, the objective of this study was to assess adhesion to, and invasion of, the ECM by these two related but distinct Naegleria species. N. fowleri exhibited a higher level of adhesion to the ECM components laminin-1, fibronectin and collagen I. Scanning electron microscopy revealed that N. fowleri attached on ECM substrata exhibited a spread-out appearance that included the presence of focal adhesion-like structures. Western immunoblotting revealed two integrin-like proteins for both species, but one of these, with a molecular mass of approximately 70 kDa, was detected at a higher level in N. fowleri. Confocal microscopy indicated that the integrin-like proteins co-localized to the focal adhesion-like structures. Furthermore, anti-integrin antibody decreased adhesion of N. fowleri to ECM components. Finally, N. fowleri disrupted 3D ECM scaffolds, while N. lovaniensis had a minimal effect. Collectively, these results indicate a distinction in adhesion to, and invasion of, ECM proteins between N. fowleri and N. lovaniensis. PMID:22222499

Jamerson, Melissa; da Rocha-Azevedo, Bruno; Cabral, Guy A.

2012-01-01

225

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, Mickael

2013-01-01

226

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

PubMed Central

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

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

2013-01-01

227

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

228

Exchange of adsorbed serum proteins during adhesion of Staphylococcus aureus to an abiotic surface and Candida albicans hyphae--an AFM study.  

PubMed

Staphylococcus aureus and Candida albicans are the second and third most commonly isolated microorganisms in hospital-related-infections, that are often multi-species in nature causing high morbidity and mortality. Here, adhesion forces between a S. aureus strain and abiotic (tissue-culture-polystyrene, TCPS) or partly biotic (TCPS with adhering hyphae of C. albicans) surfaces were investigated in presence of fetal-bovine-serum or individual serum proteins and related with staphylococcal adhesion. Atomic-force-microscopy was used to measure adhesion forces between S. aureus and the abiotic and biotic surfaces. Adsorption of individual serum proteins like albumin and apo-transferrin to abiotic TCPS surfaces during 60min, impeded development of strong adhesion forces as compared to fibronectin, while 60min adsorption of proteins from fetal-bovine-serum yielded a decrease in adhesion force from -5.7nN in phosphate-buffered-saline to -0.6nN. Adsorption of albumin and apo-transferrin also decreased staphylococcal adhesion forces to hyphae as compared with fibronectin. During 60min exposure to fetal-bovine-serum however, initial (5min protein adsorption) staphylococcal adhesion forces were low (-1.6nN), but strong adhesion forces of around -5.5nN were restored within 60min. This suggests for the first time that in whole fetal-bovine-serum exchange of non-adhesive proteins by fibronectin occurs on biotic C. albicans hyphal surfaces. No evidence was found for such protein exchange on abiotic TCPS surfaces. Staphylococcal adhesion of abiotic and biotic surfaces varied in line with the adhesion forces and was low on TCPS in presence of fetal-bovine-serum. On partly biotic TCPS, staphylococci aggregated in presence of fetal-bovine-serum around adhering C. albicans hyphae. PMID:23707849

Ovchinnikova, Ekaterina S; van der Mei, Henny C; Krom, Bastiaan P; Busscher, Henk J

2013-10-01

229

Attenuation of cell adhesion in lymphocytes is regulated by CYTIP, a protein which mediates signal complex sequestration.  

PubMed

An important theme in molecular cell biology is the regulation of protein recruitment to the plasma membrane. Fundamental biological processes such as proliferation, differentiation or leukocyte functions are initiated and controlled through the reversible binding of signaling proteins to phosphorylated membrane components. This is mediated by specialized interaction modules, such as SH2 and PH domains. Cytohesin-1 is an intracellular guanine nucleotide exchange factor, which regulates leukocyte adhesion. The activity of cytohesin-1 is controlled by phospho inositide-dependent membrane recruitment. An interacting protein was identified, the expression of which is upregulated by cytokines in hematopoietic cells. This molecule, CYTIP, is also recruited to the cell cortex by integrin signaling via its PDZ domain. However, stimulation of Jurkat cells with phorbol ester results in re-localization of CYTIP to the cytoplasm, and membrane detachment of cytohesin-1 strictly requires co-expression of CYTIP. Consequently, stimulated adhesion of Jurkat cells to intracellular adhesion molecule-1 is repressed by CYTIP. These findings outline a novel mechanism of signal chain abrogation through sequestration of a limiting component by specific protein-protein interactions. PMID:12606567

Boehm, Thomas; Hofer, Susanne; Winklehner, Patricia; Kellersch, Bettina; Geiger, Christiane; Trockenbacher, Alexander; Neyer, Susanne; Fiegl, Heidi; Ebner, Susanne; Ivarsson, Lennart; Schneider, Rainer; Kremmer, Elisabeth; Heufler, Christine; Kolanus, Waldemar

2003-03-01

230

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

Microsoft Academic Search

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

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

1998-01-01

231

EspC promotes epithelial cell detachment by enteropathogenic Escherichia coli via sequential cleavages of a cytoskeletal protein and then focal adhesion proteins.  

PubMed

EspC is a non-locus of enterocyte effacement (LEE)-encoded autotransporter produced by enteropathogenic Escherichia coli (EPEC) that is secreted to the extracellular milieu by a type V secretion system and then translocated into epithelial cells by the type III secretion system. Here, we show that this efficient EspC delivery into the cell leads to a cytopathic effect characterized by cell rounding and cell detachment. Thus, EspC is the main protein involved in epithelial cell cytotoxicity detected during EPEC adhesion and pedestal formation assays. The cell detachment phenotype is triggered by cytoskeletal and focal adhesion disruption. EspC-producing EPEC is able to cleave fodrin, paxillin, and focal adhesion kinase (FAK), but these effects are not observed when cells are infected with an espC isogenic mutant. Recovery of these phenotypes by complementing the mutant with the espC gene but not with the espC gene mutated in the serine protease motif highlights the role of the protease activity of EspC in the cell detachment phenotype. In vitro assays using purified proteins showed that EspC, but not EspC with an S256I substitution [EspCS256I], directly cleaves these cytoskeletal and focal adhesion proteins. Kinetics of protein degradation indicated that EspC-producing EPEC first cleaves fodrin (within the 11th and 9th repetitive units at the Q1219 and D938 residues, respectively), and this event sequentially triggers paxillin degradation, FAK dephosphorylation, and FAK degradation. Thus, cytoskeletal and focal adhesion protein cleavage leads to the cell rounding and cell detachment promoted by EspC-producing EPEC. PMID:24643541

Navarro-Garcia, Fernando; Serapio-Palacios, Antonio; Vidal, Jorge E; Salazar, M Isabel; Tapia-Pastrana, Gabriela

2014-06-01

232

Mammalian Adenylyl Cyclase-associated Protein 1 (CAP1) Regulates Cofilin Function, the Actin Cytoskeleton, and Cell Adhesion*  

PubMed Central

CAP (adenylyl cyclase-associated protein) was first identified in yeast as a protein that regulates both the actin cytoskeleton and the Ras/cAMP pathway. Although the role in Ras signaling does not extend beyond yeast, evidence supports that CAP regulates the actin cytoskeleton in all eukaryotes including mammals. In vitro actin polymerization assays show that both mammalian and yeast CAP homologues facilitate cofilin-driven actin filament turnover. We generated HeLa cells with stable CAP1 knockdown using RNA interference. Depletion of CAP1 led to larger cell size and remarkably developed lamellipodia as well as accumulation of filamentous actin (F-actin). Moreover, we found that CAP1 depletion also led to changes in cofilin phosphorylation and localization as well as activation of focal adhesion kinase (FAK) and enhanced cell spreading. CAP1 forms complexes with the adhesion molecules FAK and Talin, which likely underlie the cell adhesion phenotypes through inside-out activation of integrin signaling. CAP1-depleted HeLa cells also had substantially elevated cell motility as well as invasion through Matrigel. In summary, in addition to generating in vitro and in vivo evidence further establishing the role of mammalian CAP1 in actin dynamics, we identified a novel cellular function for CAP1 in regulating cell adhesion. PMID:23737525

Zhang, Haitao; Ghai, Pooja; Wu, Huhehasi; Wang, Changhui; Field, Jeffrey; Zhou, Guo-Lei

2013-01-01

233

Transforming growth factor beta-induced (TGFBI) is an anti-adhesive protein regulating the invasive growth of melanoma cells.  

PubMed

Melanoma is a malignancy characterized by high invasive/metastatic potential, with no efficient therapy after metastasis. Understanding the molecular mechanisms underlying the invasive/metastatic tendency is therefore important. Our genome-wide gene expression analyses revealed that human melanoma cell lines WM793 and especially WM239 (vertical growth phase and metastatic cells, respectively) overexpress the extracellular matrix (ECM) protein transforming growth factor ? induced (TGFBI). In adhesion assays, recombinant TGFBI was strongly anti-adhesive for both melanoma cells and skin fibroblasts. TGFBI further impaired the adhesion of melanoma cells to the adhesive ECM proteins fibronectin, collagen-I, and laminin, known to interact with it. Unexpectedly, WM239 cells migrated/invaded more effectively in three-dimensional collagen-I and Matrigel cultures after knockdown of TGFBI by shRNA expression. However, in the physiological subcutaneous microenvironment in nude mice, after TGFBI knockdown, these cells showed markedly impaired tumor growth and invasive capability; the initially formed small tumors later underwent myxoid degeneration and completely regressed. By contrast, the expanding control tumors showed intense TGFBI staining at the tumor edges, co-localizing with the fibrillar fibronectin/tenascin-C/periostin structures that characteristically surround melanoma cells at invasion fronts. Furthermore, TGFBI was found in similar fibrillar structures in clinical human melanoma metastases as well, co-localizing with fibronectin. These data imply an important role for TGFBI in the ECM deposition and invasive growth of melanoma cells, rendering TGFBI a potential target for therapeutic interventions. PMID:22326753

Nummela, Pirjo; Lammi, Johanna; Soikkeli, Johanna; Saksela, Olli; Laakkonen, Pirjo; Hölttä, Erkki

2012-04-01

234

Regulation of T-lymphocyte motility, adhesion and de-adhesion by a cell surface mechanism directed by low density lipoprotein receptor-related protein 1 and endogenous thrombospondin-1.  

PubMed

T lymphocytes are highly motile and constantly reposition themselves between a free-floating vascular state, transient adhesion and migration in tissues. The regulation behind this unique dynamic behaviour remains unclear. Here we show that T cells have a cell surface mechanism for integrated regulation of motility and adhesion and that integrin ligands and CXCL12/SDF-1 influence motility and adhesion through this mechanism. Targeting cell surface-expressed low-density lipoprotein receptor-related protein 1 (LRP1) with an antibody, or blocking transport of LRP1 to the cell surface, perturbed the cell surface distribution of endogenous thrombospondin-1 (TSP-1) while inhibiting motility and potentiating cytoplasmic spreading on intercellular adhesion molecule 1 (ICAM-1) and fibronectin. Integrin ligands and CXCL12 stimulated motility and enhanced cell surface expression of LRP1, intact TSP-1 and a 130,000 MW TSP-1 fragment while preventing formation of a de-adhesion-coupled 110 000 MW TSP-1 fragment. The appearance of the 130 000 MW TSP-1 fragment was inhibited by the antibody that targeted LRP1 expression, inhibited motility and enhanced spreading. The TSP-1 binding site in the LRP1-associated protein, calreticulin, stimulated adhesion to ICAM-1 through intact TSP-1 and CD47. Shear flow enhanced cell surface expression of intact TSP-1. Hence, chemokines and integrin ligands up-regulate a dominant motogenic pathway through LRP1 and TSP-1 cleavage and activate an associated adhesion pathway through the LRP1-calreticulin complex, intact TSP-1 and CD47. This regulation of T-cell motility and adhesion makes pro-adhesive stimuli favour motile responses, which may explain why T cells prioritize movement before permanent adhesion. PMID:24877199

Talme, Toomas; Bergdahl, Eva; Sundqvist, Karl-Gösta

2014-06-01

235

Development of a rapid immunochromatographic test using a recombinant thrombospondin-related adhesive protein of Babesia gibsoni.  

PubMed

We developed an immunochromatographic test (ICT) with the full-length of thrombospondin-related adhesive protein of Babesia gibsoni expressed by the modified expression method. The developed ICT showed high sensitivity, specificity, and kappa value with a reference test (100%, 93.78%, and 0.8976, respectively), indicating that the ICT could be a new practical diagnostic test for B. gibsoni infection. PMID:22795671

Goo, Youn-Kyoung; Lee, Naeun; Terkawi, Mohamad Alaa; Luo, Yuzi; Aboge, Gabriel Oluga; Nishikawa, Yoshifumi; Suzuki, Hiroshi; Kim, Suk; Xuan, Xuenan

2012-12-21

236

Up-Regulation, Nuclear Import, and Tumor Growth Stimulation of the Adhesion Protein p120ctn in Pancreatic Cancer  

Microsoft Academic Search

Background & Aims: Cell adhesion proteins have been implicated as tumor suppressors because they prevent malignant cells from dissociating their cell contacts. We have studied the role of p120ctn, a recently discovered member of the cadherin\\/catenin family, in human pan- creatic cancer. Methods: In 32 resection specimens of pancreatic adenocarcinoma and 10control samples the expression of p120ctn was studied by

JULIA MAYERLE; HELMUT FRIESS; MARKUS W. BUCHLER; JURGEN SCHNEKENBURGER; FRANK U. WEISS; WOLFRAM DOMSCHKE; MARKUS M. LERCH

2003-01-01

237

Src kinase determines the dynamic exchange of the docking protein NEDD9 (neural precursor cell expressed developmentally down-regulated gene 9) at focal adhesions.  

PubMed

Dynamic exchange of molecules between the cytoplasm and integrin-based focal adhesions provides a rapid response system for modulating cell adhesion. Increased residency time of molecules that regulate adhesion turnover contributes to adhesion stability, ultimately determining migration speed across two-dimensional surfaces. In the present study we test the role of Src kinase in regulating dynamic exchange of the focal adhesion protein NEDD9/HEF1/Cas-L. Using either chemical inhibition or fibroblasts genetically null for Src together with fluorescence recovery after photobleaching (FRAP), we find that Src significantly reduces NEDD9 exchange at focal adhesions. Analysis of NEDD9 mutant constructs with the two major Src-interacting domains disabled revealed the greatest effects were due to the NEDD9 SH2 binding domain. This correlated with a significant change in two-dimensional migratory speed. Given the emerging role of NEDD9 as a regulator of focal adhesion stability, the time of NEDD9 association at the focal adhesions is key in modulating rates of migration and invasion. Our study suggests that Src kinase activity determines NEDD9 exchange at focal adhesions and may similarly modulate other focal adhesion-targeted Src substrates to regulate cell migration. PMID:25059660

Bradbury, Peta; Bach, Cuc T; Paul, Andre; O'Neill, Geraldine M

2014-09-01

238

Denture Adhesives  

MedlinePLUS

... Zinc is a mineral that is an essential ingredient for good health. It is found in protein-rich foods such as shellfish, beef, chicken and nuts, as ... and that although they are safe to use in moderation as directed, if overused, ... product ingredients. Know that there are zinc-free denture adhesives ...

239

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

240

Pregnancy-associated plasma protein A up-regulated by progesterone promotes adhesion and proliferation of trophoblastic cells  

PubMed Central

Embryo implantation and development is a complex biological process for the establishment of the successful pregnancy. Progesterone is a critical factor in the regulation of embryo adhesion to uterine endometrium and proliferation. Although it has been reported that pregnancy-associated plasma protein A (PAPPA) is increased in pregnant women, the relationship between progesterone and PAPPA, and the effects of PAPPA on embryo adhesion and proliferation are still not clear. The present results showed that the serum level of progesterone and PAPPA was closely correlated by ELISA assay (p < 0.01). PAPPA was detected in the villi of early embryo by RT-PCR, Western blot, immunohistochemistry and immunofluorescent staining. Moreover, PAPPA was significantly up-regulated by progesterone in trophoblastic (JAR) cells by Real-time PCR and ELISA assay (p < 0.01); while the expression was decreased by the progesterone receptor inhibitor RU486. The down-regulation of PAPPA by siRNA transfection or up-regulation of PAPPA by progesterone treatment significantly decreased or increased the adhesion rate of trophoblastic cells to human uterine epithelial cell lines (RL95-2 and HEC-1A), respectively (p < 0.01), as well as the proliferation of trophoblastic cells. In conclusion, PAPPA is up-regulated by progesterone, which promotes the adhesion and proliferation potential of trophoblastic cells. PMID:24817938

Wang, Jiao; Liu, Shuai; Qin, Hua-Min; Zhao, Yue; Wang, Xiao-Qi; Yan, Qiu

2014-01-01

241

Autonomous expression of a noncatalytic domain of the focal adhesion-associated protein tyrosine kinase pp125FAK.  

PubMed Central

Integrins play a central role in cellular adhesion and anchorage of the cytoskeleton and participate in the generation of intracellular signals, including tyrosine phosphorylation. We have recently isolated a cDNA encoding a unique, focal adhesion-associated protein tyrosine kinase (FAK) that is a component of an integrin-mediated signal transduction pathway. Here we report the isolation of cDNAs encoding the C-terminal, noncatalytic domain of the FAK kinase, termed FRNK (FAK-related nonkinase). Both the FAK- and FRNK-encoded polypeptides, pp125FAK and p41/p43FRNK, are expressed in normal chicken embryo cells. pp125FAK and p41/p43FRNK were localized to focal adhesions, suggesting that pp125FAK is directed to the focal adhesions by sequences within its C-terminal domain. We also show that the fibronectin-dependent increase in tyrosine phosphorylation of pp125FAK is accompanied by a concomitant posttranslational modification of p41FRNK. Images PMID:8423801

Schaller, M D; Borgman, C A; Parsons, J T

1993-01-01

242

Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action  

SciTech Connect

Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

Zhang, Haimou [Center for Infection and Immunity Research, School of Life Sciences, Hubei University, Wuhan, Hubei (China); Qin, Gangjian [Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL (United States); Liang, Gang [Children's Hospital, Harvard Medical School, Boston, MA (United States); Li, Jinan [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Chiu, Isaac [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Barrington, Robert A. [CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA (United States); Liu, Dongxu [Center for Infection and Immunity Research, School of Life Sciences, Hubei University, Wuhan, Hubei (China)]. E-mail: dxliu001@yahoo.com

2007-07-13

243

Diversifying Selection on the Thrombospondin-Related Adhesive Protein (TRAP) Gene of Plasmodium falciparum in Thailand  

PubMed Central

Sporozoites of Plasmodium falciparum are transmitted to human hosts by Anopheles mosquitoes. Thrombospondin-related adhesive protein (TRAP) is expressed in sporozoites and plays a crucial role in sporozoite gliding and invasion of human hepatocytes. A previous study showed that the TRAP gene has been subjected to balancing selection in the Gambian P. falciparum population. To further study the molecular evolution of the TRAP gene in Plasmodium falciparum, we investigated TRAP polymorphisms in P. falciparum isolates from Suan Phueng District in Ratchaburi Province, Thailand. The analysis of the entire TRAP coding sequences in 32 isolates identified a total of 39 single nucleotide polymorphisms (SNPs), which comprised 37 nonsynonymous and two synonymous SNPs. McDonald–Kreitman test showed that the ratio of the number of nonsynonymous to synonymous polymorphic sites within P. falciparum was significantly higher than that of the number of nonsynonymous to synonymous fixed sites between P. falciparum and P. reichenowi. Furthermore, the rate of nonsynonymous substitution was significantly higher than that of synonymous substitution within Thai P. falciparum. These results indicate that the TRAP gene has been subject to diversifying selection in the Thai P. falciparum population as well as the Gambian P. falciparum population. Comparison of our P. falciparum isolates with those from another region of Thailand (Tak province, Thailand) revealed that TRAP was highly differentiated between geographically close regions. This rapid diversification seems to reflect strong recent positive selection on TRAP. Our results suggest that the TRAP molecule is a major target of the human immune response to pre-erythrocytic stages of P. falciparum. PMID:24587387

Ohashi, Jun; Suzuki, Yuji; Naka, Izumi; Hananantachai, Hathairad; Patarapotikul, Jintana

2014-01-01

244

Localization of Vascular Adhesion Protein-1 (VAP-1) in the Human Eye  

PubMed Central

Recently we showed a critical role for Vascular Adhesion Protein-1 (VAP-1) in rodents during acute ocular inflammation, angiogenesis, and diabetic retinal leukostasis. However, the expression of VAP-1 in the human eye is unknown. VAP-1 localization was investigated by immunohistochemistry. Five ?m thick sections were generated from human ocular tissues embedded in paraffin. Sections were incubated overnight with primary mAbs against VAP-1 (5?g/ml), smooth muscle actin (1?g/ml), CD31 or isotype-matched IgG at 4°C. Subsequently, a secondary mAb was used for 30min at room temperature, followed by Dako Envision + HRP (AEC) System for signal detection. The stained sections were examined using light microscopy and the signal intensity was quantified by two masked evaluators and graded into 4 discrete categories. In all examined ocular tissues, VAP-1 staining was confined to the vasculature. VAP-1 labeling showed the highest intensity in both arteries and veins of neuronal tissues; retina, and optic nerve, and the lowest intensity in the iris vasculature (p<0.05). Scleral and choroidal vessels showed moderate staining for VAP-1. VAP-1 intensity was significantly higher in the arteries compared to veins (p<0.05). Furthermore, VAP-1 staining in arteries co-localized with both CD31 and smooth muscle actin (sm-actin) staining, suggesting expression of VAP-1 in endothelial cells, smooth muscle cells or potentially pericytes. In conclusion, Immunohistochemistry reveals constitutive expression of VAP-1 in human ocular tissues. VAP-1 expression is exclusive to the vasculature with arteries showing significantly higher expression than veins. Furthermore, VAP-1 expression in the ocular vasculature is heterogeneous, with the vessels of the optic nerve and the retina showing highest expressions. These results characterize VAP-1 expression in human ocular tissues. PMID:19761765

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

2009-01-01

245

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

246

The adhesion modulation protein, AmpA localizes to an endocytic compartment and influences substrate adhesion, actin polymerization and endocytosis in vegetative Dictyostelium cells  

PubMed Central

Background AmpA is a secreted 24Kd protein that has pleiotropic effects on Dictyostelium development. Null mutants delay development at the mound stage with cells adhering too tightly to the substrate. Prestalk cells initially specify as prespore cells and are delayed in their migration to the mound apex. Extracellular AmpA can rescue these defects, but AmpA is also necessary in a cell autonomous manner for anterior like cells (ALCs) to migrate to the upper cup. The ALCs are only 10% of the developing cell population making it difficult to study the cell autonomous effect of AmpA on the migration of these cells. AmpA is also expressed in growing cells, but, while it contains a hydrophobic leader sequence that is cleaved, it is not secreted from growing cells. This makes growing cells an attractive system for studying the cell autonomous function of AmpA. Results In growing cells AmpA plays an environment dependent role in cell migration. Excess AmpA facilitates migration on soft, adhesive surfaces but hinders migration on less adhesive surfaces. AmpA also effects the level of actin polymerization. Knockout cells polymerize less actin while over expressing cells polymerize more actin than wild type. Overexpression of AmpA also causes an increase in endocytosis that is traced to repeated formation of multiple endocytic cups at the same site on the membrane. Immunofluorescence analysis shows that AmpA is found in the Golgi and colocalizes with calnexin and the slow endosomal recycling compartment marker, p25, in a perinuclear compartment. AmpA is found on the cell periphery and is endocytically recycled to the perinuclear compartment. Conclusion AmpA is processed through the secretory pathway and traffics to the cell periphery where it is endocytosed and localizes to what has been defined as a slow endosomal recycling compartment. AmpA plays a role in actin polymerization and cell substrate adhesion. Additionally AmpA influences cell migration in an environment dependent manner. Wild type cells show very little variation in migration rates under the different conditions examined here, but either loss or over expression of AmpA cause significant substrate and environment dependent changes in migration. PMID:23126556

2012-01-01

247

Structure and function of a bacterial Fasciclin I Domain Protein elucidates function of related cell adhesion proteins such as TGFBIp and periostin.  

PubMed

Fasciclin I (FAS1) domains have important roles in cell adhesion, which are not understood despite many structural and functional studies. Examples of FAS1 domain proteins include TGFBIp (?ig-h3) and periostin, which function in angiogenesis and development of cornea and bone, and are also highly expressed in cancer tissues. Here we report the structure of a single-domain bacterial fasciclin I protein, Fdp, in the free-living photosynthetic bacterium Rhodobacter sphaeroides, and show that it confers cell adhesion properties in vivo. A binding site is identified which includes the most highly conserved region and is adjacent to the N-terminus. By mapping this onto eukaryotic homologues, which all contain tandem FAS1 domains, it is concluded that the interaction site is normally buried in the dimer interface. This explains why corneal dystrophy mutations are concentrated in the C-terminal domain of TGFBIp and suggests new therapeutic approaches. PMID:23772377

Moody, Robert G; Williamson, Mike P

2013-01-01

248

The impact of dendrimer-grafted modifications to model silicon surfaces on protein adsorption and bacterial adhesion.  

PubMed

In the oral cavity, omnipresent salivary protein films (pellicle) mediate bacterial adhesion and biofilm formation on natural tissues as well as on artificial implant surfaces, which may cause serious infectious diseases like periimplantitis. The purpose of this in vitro study was to investigate the adsorption/desorption behaviour of human saliva on model surfaces grafted with polyamidoamine (PAMAM) dendrimer molecules compared to self-assembled monolayers (SAMs) exhibiting the same terminal functions (-NH(2), -COOH) by two complementary analytical methods. Furthermore, the role of saliva conditioning of PAMAM and analogous SAM modifications on the adhesion of Streptococcus gordonii DL1, an early oral colonizer, was investigated. In contrast to SAMs, PAMAM-grafted surfaces showed reduced streptococcal adherence in the absence of pre-adsorbed saliva similar to the level obtained for poly(ethylene glycol) (PEG) coatings. Moreover, coatings of PAMAM-NH(2) maintained their bacteria-repellent behaviour even after saliva-conditioning. As a general outcome, it was found that lower amounts of protein adsorbed on PAMAM coatings than on analogous SAMs. Since this study demonstrates that covalently bound PAMAM dendrimers can modulate the oral bacterial response, this approach has significant potential for the development of anti-adhesive biomaterial surfaces that are conditioned with proteinaceous films. PMID:21906807

Eichler, Mirjam; Katzur, Verena; Scheideler, Lutz; Haupt, Michael; Geis-Gerstorfer, Juergen; Schmalz, Gottfried; Ruhl, Stefan; Müller, Rainer; Rupp, Frank

2011-12-01

249

The Leu-Arg-Glu (LRE) adhesion motif in proteins of the neuromuscular junction with special reference to proteins of the carboxylesterase/cholinesterase family.  

PubMed

Short linear motifs confer evolutionary flexibility on proteins as they can be added with relative ease allowing the acquisition of new functions. Such motifs may mediate a variety of signalling functions. The adhesion-mediating Leu-Arg-Glu (LRE) motif is enriched in laminin beta 2, and has been observed in other proteins, including members of the carboxylesterase/cholinesterase family. It acts as a stop signal for growing axons in the developing neuromuscular junction, binding to the voltage-gated calcium channel. In this bioinformatic analysis, we have investigated the presence of the motif in proteins of the neuromuscular junction, and have also examined its structural position and potential for ligand interaction, as well as phylogenetic conservation, in the carboxylesterase/cholinesterase family. The motif was observed to occur with a significantly higher frequency than expected in the UniProt/Swiss-Prot database, as well as in four individual species (human, mouse, Caenorhabditis elegans and Drosophila melanogaster). Examination of its presence in neuromuscular junction proteins showed it to be enriched in certain proteins of the synaptic basement membrane, including laminin, agrin, acetylcholinesterase and tenascin. A highly significant enrichment was observed in cytoskeletal proteins, particularly intermediate filament proteins and members of the spectrin family. In the carboxylesterase/cholinesterase family, the motif was observed in four conserved positions in the protein structure. It is present in the majority of mammalian acetylcholinesterases, as well as acetylcholinesterases from electric fish and a number of invertebrates. In insects, it is present in the ace-2, rather than in the synaptic ace-1, enzyme. It is also observed in the cholinesterase-like adhesion molecules (neuroligins, neurotactin and glutactin). It is never seen in butyrylcholinesterases, which do not mediate cell adhesion. In conclusion, the significant enrichment of the motif in certain classes of protein, as well as its conserved presence and structural positioning in one protein family, suggests that it has specific functions both in cell adhesion in the neuromuscular junction and in maintaining the structural integrity of the cytoskeleton. PMID:23850873

Johnson, Glynis; Moore, Samuel W

2013-09-01

250

Flagellar adhesion-dependent regulation of Chlamydomonas adenylyl cyclase in vitro: a possible role for protein kinases in sexual signaling  

PubMed Central

Interactions between adhesion molecules, agglutinins, on the surfaces of the flagella of mt+ and mt- gametes in Chlamydomonas rapidly generate a sexual signal, mediated by cAMP, that prepares the cells for fusion to form a zygote. The mechanism that couples agglutinin interactions to increased cellular levels of cAMP is unknown. In previous studies on the adenylyl cyclase in flagella of a single mating type (i.e., non-adhering flagella) we presented evidence that the gametic form of the enzyme, but not the vegetative form, was regulated by phosphorylation and dephosphorylation (Zhang, Y., E. M. Ross, and W. J. Snell. 1991. J. Biol. Chem. 266:22954-22959; Zhang, Y., and W. J. Snell. 1993. J. Biol. Chem. 268:1786-1791). In the present report we describe studies on regulation of flagellar adenylyl cyclase during adhesion in a cell-free system. The results show that the activity of gametic flagellar adenylyl cyclase is regulated by adhesion in vitro between flagella isolated from mt+ and mt- gametes. After mixing mt+ and mt- flagella together for 15 s in vitro, adenylyl cyclase activity was increased two- to threefold compared to that of the non-mixed (non- adhering), control flagella. This indicates that the regulation of gametic flagellar adenylyl cyclase during the early steps of fertilization is not mediated by signals from the cell body, but is a direct and primary response to interactions between mt+ and mt- agglutinins. By use of this in vitro assay, we discovered that 50 nM staurosporine (a protein kinase inhibitor) blocked adhesion-induced activation of adenylyl cyclase in vitro, while it had no effect on adenylyl cyclase activity of non-adhering gametic flagella. This same low concentration of staurosporine also inhibited adhesion-induced increases in vivo in cellular cAMP and blocked subsequent cellular responses to adhesion. Taken together, our results indicate that flagellar adenylyl cyclase in Chlamydomonas gametes is coupled to interactions between mt+ and mt- agglutinins by a staurosporine- sensitive activity, probably a protein kinase. PMID:8175884

1994-01-01

251

c-Cbl Ubiquitin Ligase Regulates Focal Adhesion Protein Turnover and Myofibril Degeneration Induced by Neutrophil Protease Cathepsin G*  

PubMed Central

The neutrophil-derived serine protease, cathepsin G (Cat.G), has been shown to induce myocyte detachment and apoptosis by anoikis through down-regulation of focal adhesion (FA) signaling. However, the mechanisms that control FA protein stability and turnover in myocytes are not well understood. Here, we have shown that the Casitas b-lineage lymphoma (c-Cbl), adaptor protein with an intrinsic E3 ubiquitin ligase activity, is involved in FA and myofibrillar protein stability and turnover in myocytes. Cat.G treatment induced c-Cbl activation and its interaction with FA proteins. Deletion of c-Cbl using c-Cbl knock-out derived myocytes or inhibition of c-Cbl ligase activity significantly reduced FA protein degradation, myofibrillar degeneration, and myocyte apoptosis induced by Cat.G. We also found that inhibition of the proteasome activity, but not the lysosome or the calpain activity, markedly attenuated FA and myofibrillar protein degradation induced by Cat.G. Interestingly, c-Cbl activation induced by Cat.G was mediated through epidermal growth factor receptor (EGFR) transactivation as inhibition of EGFR kinase activity markedly attenuated c-Cbl phosphorylation and FA protein degradation induced by Cat.G. These findings support a model in which neutrophil protease Cat.G promotes c-Cbl interaction with FA proteins, resulting in enhanced c-Cbl-mediated FA protein ubiquitination and degradation, myofibril degradation, and subsequent down-regulation of myocyte survival signaling. PMID:22203672

Rafiq, Khadija; Guo, Jianfen; Vlasenko, Liudmila; Guo, Xinji; Kolpakov, Mikhail A.; Sanjay, Archana; Houser, Steven R.; Sabri, Abdelkarim

2012-01-01

252

[The role of the ERM protein family in maintaining cellular polarity, adhesion and regulation of cell motility].  

PubMed

Ezrin, radixin and moesin, forming the ERM protein family, act as molecular crosslinkers between actin filaments and proteins anchored in the cell membrane. By participating in a complex intracellular network of signal transduction pathways, ERM proteins play a key role in the regulation of adhesion and polarity of normal cells through interactions with membrane molecules, e.g. E-cadherin. Dynamic cytoskeletal transformations, in which the ERM and Rho GTPases are involved, lead to the formation of membrane-cytoplasmic structures, such as filopodia and lamellipodia, which are responsible for cellular motility. The interactions of ERM proteins with active Akt kinase cause the acquisition of antiapoptotic cellular features by downregulation of the proapoptotic protein Bad. ERM protein activity is regulated by phosphorylation/dephosphorylation reactions and linking phosphatidylinositols. The model of activation based on the molecular conformation changes by breaking the intramolecular bonds and exposing actin binding sites is essential for the proper functioning of the ERM proteins. Additionally, the connection types between the ERM and membrane proteins (direct or indirect by EBP50 and E3KARP) play an important role in transduction of signals from the extracellular matrix. Due to the wide range of ezrin, radixin and moesin cytophysiological features, detailed exploration of the ERM biochemistry will provide a series of answers to questions about ambiguous functions in many intracellular signal transduction pathways. PMID:22470191

Ha?o?, Agnieszka; Donizy, Piotr

2012-01-01

253

Immunolocalization of keratin-associated beta-proteins in developing epidermis of lizard suggests that adhesive setae contain glycine--cysteine-rich proteins.  

PubMed

The localization of specific keratin-associated beta-proteins (formerly referred to as beta-keratins) in the embryonic epidermis of lizards is not known. Two specific keratin-associated beta-proteins of the epidermis, one representing the glycine-rich subfamily (HgG5) and the other the glycine-cysteine medium-rich subfamily (HgGC10), have been immunolocalized at the ultrastructural level in the lizard Anolis lineatopus. The periderm and granulated subperiderm are most immunonegative for these proteins. HgG5 is low to absent in theOberhäutchen layer while is present in the forming beta-layer, and disappears in mesos- and alpha-layers. Instead, HgGC10 is present in the Oberhäutchen, beta-, and also in the following alpha-layers, and specifically accumulates in the developing adhesive setae but not in the surrounding cells of the clear layer. Therefore, setae and their terminal spatulae that adhere to surfaces allowing these lizards to walk vertically contain cysteine-glycine rich proteins. The study suggests that, like in adult and regenerating epidermis, the HgGC10 protein is not only accumulated in cells of the beta-layer but also in those forming the alpha-layer. This small protein therefore is implicated in resistance, flexibility, and stretching of the epidermal layers. It is also hypothesized that the charges of these proteins may influence adhesion of the setae of pad lamellae. Conversely, glycine-rich beta-proteins like HgG5 give rise to the dense, hydrophobic, and chromophobic corneous material of the resistant beta-layer. This result suggests that the differential accumulation of keratin-associated beta-proteins over the alpha-keratin network determines differences in properties of the stratified layers of the epidermis of lizards. PMID:23108977

Alibardi, Lorenzo

2013-01-01

254

Mechanism for Adhesion G Protein-Coupled Receptor GPR56-Mediated RhoA Activation Induced By Collagen III Stimulation  

PubMed Central

GPR56 is a member of the adhesion G protein-coupled receptor (GPCR) family. Despite the importance of GPR56 in brain development, where mutations cause a devastating human brain malformation called bilateral frontoparietal polymicrogyria (BFPP), the signaling mechanism(s) remain largely unknown. Like many other adhesion GPCRs, GPR56 is cleaved via a GPCR autoproteolysis-inducing (GAIN) domain into N- and C-terminal fragments (GPR56N and GPR56C); however, the biological significance of this cleavage is elusive. Taking advantage of the recent identification of a GPR56 ligand and the presence of BFPP-associated mutations, we investigated the molecular mechanism of GPR56 signaling. We demonstrate that ligand binding releases GPR56N from the membrane-bound GPR56C and triggers the association of GPR56C with lipid rafts and RhoA activation. Furthermore, one of the BFPP-associated mutations, L640R, does not affect collagen III-induced lipid raft association of GPR56. Instead, it specifically abolishes collagen III-mediated RhoA activation. Together, these findings reveal a novel signaling mechanism that may apply to other members of the adhesion GPCR family. PMID:24949629

Luo, Rong; Jeong, Sung-Jin; Yang, Annie; Wen, Miaoyun; Saslowsky, David E.; Lencer, Wayne I.; Araç, Demet; Piao, Xianhua

2014-01-01

255

A Role for the Retinoblastoma Protein As a Regulator of Mouse Osteoblast Cell Adhesion: Implications for Osteogenesis and Osteosarcoma Formation  

PubMed Central

The retinoblastoma protein (pRb) is a cell cycle regulator inactivated in most human cancers. Loss of pRb function results from mutations in the gene coding for pRb or for any of its upstream regulators. Although pRb is predominantly known as a cell cycle repressor, our data point to additional pRb functions in cell adhesion. Our data show that pRb regulates the expression of a wide repertoire of cell adhesion genes and regulates the assembly of the adherens junctions required for cell adhesion. We conducted our studies in osteoblasts, which depend on both pRb and on cell-to-cell contacts for their differentiation and function. We generated knockout mice in which the RB gene was excised specifically in osteoblasts using the cre-lox P system and found that osteoblasts from pRb knockout mice did not assemble adherens junction at their membranes. pRb depletion in wild type osteoblasts using RNAi also disrupted adherens junctions. Microarrays comparing pRb-expressing and pRb-deficient osteoblasts showed that pRb controls the expression of a number of cell adhesion genes, including cadherins. Furthermore, pRb knockout mice showed bone abnormalities consistent with osteoblast adhesion defects. We also found that pRb controls the function of merlin, a well-known regulator of adherens junction assembly, by repressing Rac1 and its effector Pak1. Using qRT-PCR, immunoblots, co-immunoprecipitation assays, and immunofluorescent labeling, we observed that pRb loss resulted in Rac1 and Pak1 overexpression concomitant with merlin inactivation by Pak1, merlin detachment from the membrane, and adherens junction loss. Our data support a pRb function in cell adhesion while elucidating the mechanism for this function. Our work suggests that in some tumor types pRb inactivation results in both a loss of cell cycle control that promotes initial tumor growth as well as in a loss of cell-to-cell contacts, which contributes to later stages of metastasis. PMID:21085651

Sosa-Garcia, Bernadette; Gunduz, Volkan; Vazquez-Rivera, Viviana; Cress, W. Douglas; Wright, Gabriela; Bian, Haikuo; Hinds, Philip W.; Santiago-Cardona, Pedro G.

2010-01-01

256

SpyAD, a moonlighting protein of group A Streptococcus contributing to bacterial division and host cell adhesion.  

PubMed

Group A streptococcus (GAS) is a human pathogen causing a wide repertoire of mild and severe diseases for which no vaccine is yet available. We recently reported the identification of three protein antigens that in combination conferred wide protection against GAS infection in mice. Here we focused our attention on the characterization of one of these three antigens, Spy0269, a highly conserved, surface-exposed, and immunogenic protein of unknown function. Deletion of the spy0269 gene in a GAS M1 isolate resulted in very long bacterial chains, which is indicative of an impaired capacity of the knockout mutant to properly divide. Confocal microscopy and immunoprecipitation experiments demonstrated that the protein was mainly localized at the cell septum and could interact in vitro with the cell division protein FtsZ, leading us to hypothesize that Spy0269 is a member of the GAS divisome machinery. Predicted structural domains and sequence homologies with known streptococcal adhesins suggested that this antigen could also play a role in mediating GAS interaction with host cells. This hypothesis was confirmed by showing that recombinant Spy0269 could bind to mammalian epithelial cells in vitro and that Lactococcus lactis expressing Spy0269 on its cell surface could adhere to mammalian cells in vitro and to mice nasal mucosa in vivo. On the basis of these data, we believe that Spy0269 is involved both in bacterial cell division and in adhesion to host cells and we propose to rename this multifunctional moonlighting protein as SpyAD (Streptococcus pyogenes Adhesion and Division protein). PMID:24778116

Gallotta, Marilena; Gancitano, Giovanni; Pietrocola, Giampiero; Mora, Marirosa; Pezzicoli, Alfredo; Tuscano, Giovanna; Chiarot, Emiliano; Nardi-Dei, Vincenzo; Taddei, Anna Rita; Rindi, Simonetta; Speziale, Pietro; Soriani, Marco; Grandi, Guido; Margarit, Immaculada; Bensi, Giuliano

2014-07-01

257

Effects of photochemically immobilized polymer coatings on protein adsorption, cell adhesion, and the foreign body reaction to silicone rubber.  

PubMed

Photochemical immobilization technology was utilized to covalently couple polymers to silicone rubber either at multiple points along a polymer backbone or at the endpoint of an amphiphilic chain. The coating variants then were tested in vitro and in vivo for improvement of desired responses compared to uncoated silicone rubber. All coating variants suppressed the adsorption of fibrinogen and immunoglobulin G, and most also inhibited fibroblast growth by 90-99%. None of the coating variants inhibited monocyte or neutrophil adhesion in vitro. However, the surfaces that supported the highest levels of monocyte adhesion also elicited the lowest secretion of pro-inflammatory cytokines. None of the materials elicited a strong inflammatory response or significantly (p< 0.05) reduced the thickness of the fibrous capsule when implanted subcutaneously in rats. Overall, the most passivating coating variant was an endpoint immobilized polypeptide that reduced protein adsorption, inhibited fibroblast growth by 90%, elicited low cytokine secretion from monocytes, and reduced fibrous encapsulation by 33%. In general, although some coating variants modified the adsorption of proteins and the behavior of leukocytes or fibroblasts in vitro, none abolished the development of a fibrous capsule in vivo. PMID:10397932

DeFife, K M; Shive, M S; Hagen, K M; Clapper, D L; Anderson, J M

1999-03-01

258

Restoring E-cadherin-mediated cell-cell adhesion increases PTEN protein level and stability in human breast carcinoma cells  

SciTech Connect

The phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a well-characterized tumor suppressor that negatively regulates cell growth and survival. Despite the critical role of PTEN in cell signaling, the mechanisms of its regulation are still under investigation. We reported here that PTEN expression could be controlled by overexpression or knock-down of E-cadherin in several mammary carcinoma cell lines. Furthermore, we showed that the accumulation of PTEN protein in E-cadherin overexpressing cells was due to increased PTEN protein stability rather than the regulation of its transcription. The proteasome-dependent PTEN degradation pathway was impaired after restoring E-cadherin expression. Moreover, maintenance of E-cadherin mediated cell-cell adhesion was necessary for its regulating PTEN. Altogether, our results suggested that E-cadherin mediated cell-cell adhesion was essential for preventing the proteasome degradation of PTEN, which might explain how breast carcinoma cells which lost cell-cell contact proliferate rapidly and are prone to metastasis.

Li Zengxia; Wang Liying; Zhang Wen; Fu Yi; Zhao Hongbo; Hu Yali; Prins, Bram Peter [Key Laboratory of Glycoconjugate Research, Ministry of Health, Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032 (China); Zha Xiliang [Key Laboratory of Glycoconjugate Research, Ministry of Health, Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032 (China)], E-mail: xlzha@shmu.edu.cn

2007-11-09

259

Host Protein Binding and Adhesive Properties of H6 and H7 Flagella of Attaching and Effacing Escherichia coli?  

PubMed Central

It had been suggested that the flagella of enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC) might contribute to host colonization. In this study, we set out to investigate the adhesive properties of H7 and H6 flagella. We studied the abilities of EHEC EDL933 (O157:H7) and EPEC E2348/69 (O127:H6) flagella to bind to bovine mucus, host proteins such as mucins, and extracellular matrix proteins. Through several approaches, we found that H6 and H7 flagella and their flagellin monomers bind to mucins I and II and to freshly isolated bovine mucus. A genetic approach showed that EHEC and EPEC fliC deletion mutants were significantly less adherent to bovine intestinal tissue than the parental wild-type strains. In addition, we found that EPEC bacteria and H6 flagella, but not EHEC, bound largely, in a dose-dependent manner, to collagen and to a lesser extent to laminin and fibronectin. We also report that EHEC O157:H7 strains agglutinate rabbit red blood cells via their flagella, a heretofore unknown phenotype in this pathogroup. Collectively, our data demonstrate that the H6 and H7 flagella possess adhesive properties, particularly the ability to bind mucins, that may contribute to colonization of mucosal surfaces. PMID:17693516

Erdem, Aysen L.; Avelino, Fabiola; Xicohtencatl-Cortes, Juan; Giron, Jorge A.

2007-01-01

260

Mobile and three-dimensional presentation of adhesion proteins within microwells.  

PubMed

On traditional cell culture substrates cells adhere to a planar 2D surface where ligands are presented immobile. A more realistic presentation of cell adhesion ligands which can account for lateral mobility and a more tissue-like 3D presentation would allow studies addressing fundamental questions of significant importance for applications such as tissue engineering and implant intregration. To study the effect of lateral mobility of cell membrane interaction cues in three dimensions, we have developed and characterized a platform which generically enables patterning of single cells into microwells presenting a cell membrane mimetic interface pre-patterned to its walls. Here, we describe its application in presenting a soluble cell adhesive ligand coupled through streptavidin-antibody linkage to lipids in a supported lipid bilayer (SLB) coated microwell. The lateral mobility of the presented ligands was controlled through a small change in temperature. The SLB phospholipid composition was choosen such that below its melting transition at 30 °C the ligands are immobile, while above 30 °C they are laterally mobile. The platform thus enables the investigation of cell adhesion to either laterally immobile or mobile E-cadherin ligand presented on the same cell membrane mimetic surface. PMID:23868585

Andreasson-Ochsner, Mirjam; Reimhult, Erik

2013-01-01

261

Facilitation of cell adhesion by immobilized dengue viral nonstructural protein 1 (NS1): arginine-glycine-aspartic acid structural mimicry within the dengue viral NS1 antigen.  

PubMed

Dengue virus infection causes life-threatening hemorrhagic fever. Increasing evidence implies that dengue viral nonstructural protein 1 (NS1) exhibits a tendency to elicit potentially hazardous autoantibodies, which show a wide spectrum of specificity against extracellular matrix and platelet antigens. How NS1 elicits autoantibodies remains unclear. To address the hypothesis that NS1 and matrix proteins may have structural and functional similarity, cell-matrix and cell-NS1 interactions were evaluated using a cell-adhesion assay. The present study showed that dengue NS1 immobilized on coverslips resulted in more cell adhesion than did the control proteins. This cell adhesion was inhibited by peptides containing arginine-glycine-aspartic acid (RGD), a motif important for integrin-mediated cell adhesion. In addition, anti-NS1 antibodies blocked RGD-mediated cell adhesion. Although there is no RGD motif in the NS1 protein sequence, these data indicate that RGD structural mimicry exists within the NS1 antigen. PMID:12198607

Chang, Hsin-Hou; Shyu, Huey-Fen; Wang, Yo-Ming; Sun, Der-Shan; Shyu, Rong-Hwa; Tang, Shiao-Shek; Huang, Yao-Shine

2002-09-15

262

Monitoring of integrin-mediated adhesion of human ovarian cancer cells to model protein surfaces by quartz crystal resonators: evaluation in the impedance analysis mode.  

PubMed

The quartz crystal microbalance (QCM) was used to monitor specific, integrin-mediated adhesion of human ovarian cancer cells to distinct extracellular matrix (ECM) proteins immobilized on gold-coated quartz crystal resonators. The QCM was operated in the impedance analysis mode, where frequency shift as well as bandwidth are accessible on a broad range of overtones. The increase in bandwidth caused by covering the quartz resonator with cells was reproducible and largely independent of overtone order, whereas the frequency shift displayed some variability. Thus the bandwidth proved to be the more robust parameter for sensing cell adhesive events. The bandwidth increased in proportion to the number of seeded cells to the quartz crystal as long as the number was below 150,000 cells/ml. Comparing the resonance parameters on different harmonics, one finds that viscoelastic modeling with homogeneous layer systems cannot reproduce the results: lateral heterogeneity has to be taken into account. The differences in adhesive strength of human ovarian cancer cells towards selected ECM proteins monitored by QCM was in good agreement with data obtained by conventional cell adhesion assays. Strong cell adhesion was observed to the ECM proteins vitronectin (VN) and fibronectin (FN), while only weak attachment occurred on laminin. In order to prove specific, integrin alphavbeta3-mediated cell adhesion to its ligands FN and VN, the cyclic integrin alphavbeta3-directed peptide c(RGDfV) was used as competitor and significantly reversed cell adhesion. Since integrin interaction with ECM proteins is dependent on the presence of bivalent cations, cell detachment was also seen after treatment of cell monolayers with the chelator ethylene-dinitro-tetra-acetic acid (EDTA). The QCM technique is a reliable method to monitor cell adsorption to ECM-pretreated surfaces in real time. It may be an alternative tool for screening specific and selective antagonists of integrin/ECM interaction. PMID:15590287

Li, Jing; Thielemann, Christiane; Reuning, Ute; Johannsmann, Diethelm

2005-01-15

263

Vaspin inhibits cytokine-induced nuclear factor-kappa B activation and adhesion molecule expression via AMP-activated protein kinase activation in vascular endothelial cells  

PubMed Central

Background Vaspin is an adipocytokine that was recently identified in the visceral adipose tissue of diabetic rats and has anti-diabetic and anti-atherogenic effects. We hypothesized that vaspin prevents inflammatory cytokine-induced nuclear factor-kappa B (NF-?B) activation by activating AMP-activated protein kinase (AMPK) in vascular endothelial cells. Methods We examined the effects of vaspin on NF-?B activation and the expression of the NF-?B-mediated genes intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and monocyte chemoattractant protein-1 (MCP-1). Human aortic endothelial cells (HAECS) were used. Tumor necrosis factor alpha (TNF?) was used as a representative proinflammatory cytokine. Results Treatment with vaspin significantly increased the phosphorylation of AMPK and acetyl-CoA carboxylase, the down-stream target of AMPK. Furthermore, treatment with vaspin significantly decreased TNF?-induced activation of NF-?B, as well as the expression of the adhesion molecules ICAM-1, VCAM-1, E-selectin, and MCP-1. These effects were abolished following transfection of AMPK?1-specific small interfering RNA. In an adhesion assay using THP-1 cells, vaspin reduced TNF?-induced adhesion of monocytes to HAECS in an AMPK-dependent manner. Conclusions Vaspin might attenuate the cytokine-induced expression of adhesion molecule genes by inhibiting NF-?B following AMPK activation. PMID:24517399

2014-01-01

264

Cross Talk between Cell Cell and Cell Matrix Adhesion Signaling Pathways during Heart Organogenesis: Implications for Cardiac Birth Defects  

NASA Astrophysics Data System (ADS)

The anterior posterior and dorsal ventral progression of heart organogenesis is well illustrated by the patterning and activity of two members of different families of cell adhesion molecules: the calcium-dependent cadherins, specifically N-cadherin, and the extracellular matrix glycoproteins, fibronectin. N-cadherin by its binding to the intracellular molecule [beta]-catenin and fibronectin by its binding to integrins at focal adhesion sites, are involved in regulation of gene expression by their association with the cytoskeleton and through signal transduction pathways. The ventral precardiac mesoderm cells epithelialize and become stably committed by the activation of these cell matrix and intracellular signaling transduction pathways. Cross talk between the adhesion signaling pathways initiates the characteristic phenotypic changes associated with cardiomyocyte differentiation: electrical activity and organization of myofibrils. The development of both organ form and function occurs within a short interval thereafter. Mutations in any of the interacting molecules, or environmental insults affecting either of these signaling pathways, can result in embryonic lethality or fetuses born with severe heart defects. As an example, we have defined that exposure of the embryo temporally to lithium during an early sensitive developmental period affects a canonical Wnt pathway leading to [beta]-catenin stabilization. Lithium exposure results in an anterior posterior progression of severe cardiac defects.

Linask, Kersti K.; Manisastry, Shyam; Han, Mingda

2005-06-01

265

Connexin 43 and plakophilin-2 as a protein complex that regulates blood-testis barrier dynamics  

PubMed Central

The blood–testis barrier (BTB) formed by adjacent Sertoli cells is composed of coexisting tight junction (TJ), basal ectoplasmic specialization (ES), and desmosome-like junction. Desmosome-like junctions display structural features of desmosome and gap junctions, but its function at the BTB remains unknown. Herein, we demonstrate that connexin 43 (Cx43), a gap junction integral membrane protein, structurally interacts with desmosomal protein plakophilin-2 (PKP2), basal ES proteins N-cadherin and ?-catenin, and signaling molecule c-Src, but not with the TJ proteins occludin and ZO-1 in the seminiferous epithelium of adult rats. The localization of Cx43 in the seminiferous epithelium during (i) the normal epithelial cycle of spermatogenesis and (ii) anchoring junction restructuring at the Sertoli–spermatid interface induced by adjudin which mimics junction restructuring events during spermatogenesis have suggested that Cx43 is involved in cell adhesion. The knockdown of Cx43 by RNAi technique using specific siRNA duplexes was performed in primary Sertoli cell cultures with an established TJ permeability barrier that mimicked the BTB in vivo. This knockdown of Cx43 affected neither the TJ barrier function nor the steady-state levels of junction proteins of TJ, basal ES, and desmosome-like junction. However, after the knockdown of both Cx43 and PKP2, the Sertoli cell TJ barrier function was perturbed transiently. This perturbation was concomitant with a mislocalization of occludin and ZO-1 from the cell–cell interface. In summary, Cx43 and PKP2 form a protein complex within the desmosome-like junction to regulate cell adhesion at the BTB, partly through its effects on the occludin/ZO-1 complex, so as to facilitate the transit of primary preleptotene spermatocytes. PMID:19509333

Li, Michelle W. M.; Mruk, Dolores D.; Lee, Will M.; Cheng, C. Yan

2009-01-01

266

N-Terminal Gly224-Gly411 Domain in Listeria Adhesion Protein Interacts with Host Receptor Hsp60  

PubMed Central

Background Listeria adhesion protein (LAP) is a housekeeping bifunctional enzyme consisting of N-terminal acetaldehyde dehydrogenase (ALDH) and C-terminal alcohol dehydrogenase (ADH). It aids Listeria monocytogenes in crossing the epithelial barrier through a paracellular route by interacting with its host receptor, heat shock protein 60 (Hsp60). To gain insight into the binding interaction between LAP and Hsp60, LAP subdomain(s) participating in the Hsp60 interaction were investigated. Methods Using a ModBase structural model, LAP was divided into 4 putative subdomains: the ALDH region contains N1 (Met1–Pro223) and N2 (Gly224–Gly411), and the ADH region contains C1 (Gly412–Val648) and C2 (Pro649–Val866). Each subdomain was cloned and overexpressed in Escherichia coli and purified. Purified subdomains were used in ligand overlay, immunofluorescence, and bead-based epithelial cell adhesion assays to analyze each domain's affinity toward Hsp60 protein or human ileocecal epithelial HCT-8 cells. Results The N2 subdomain exhibited the greatest affinity for Hsp60 with a KD of 9.50±2.6 nM. The KD of full-length LAP (7.2±0.5 nM) to Hsp60 was comparable to the N2 value. Microspheres (1 µm diameter) coated with N2 subdomain showed significantly (P<0.05) higher binding to HCT-8 cells than beads coated with other subdomains and this binding was inhibited when HCT-8 cells were pretreated with anti-Hsp60 antibody to specifically block epithelial Hsp60. Furthermore, HCT-8 cells pretreated with purified N2 subdomain also reduced L. monocytogenes adhesion by about 4 log confirming its involvement in interaction with epithelial cells. Conclusion These data indicate that the N2 subdomain in the LAP ALDH domain is critical in initiating interaction with mammalian cell receptor Hsp60 providing insight into the molecular mechanism of pathogenesis for the development of potential anti-listerial control strategies. PMID:21738582

Jagadeesan, Balamurugan; Fleishman Littlejohn, Amy E.; Amalaradjou, Mary Anne Roshni; Singh, Atul K.; Mishra, Krishna K.; La, David; Kihara, Daisuke; Bhunia, Arun K.

2011-01-01

267

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.

268

The GPS Motif Is a Molecular Switch for Bimodal Activities of Adhesion Class G Protein-Coupled Receptors  

PubMed Central

Summary Adhesion class G protein-coupled receptors (aGPCR) form the second largest group of seven-transmembrane-spanning (7TM) receptors whose molecular layout and function differ from canonical 7TM receptors. Despite their essential roles in immunity, tumorigenesis, and development, the mechanisms of aGPCR activation and signal transduction have remained obscure to date. Here, we use a transgenic assay to define the protein domains required in vivo for the activity of the prototypical aGPCR LAT-1/Latrophilin in Caenorhabditis elegans. We show that the GPCR proteolytic site (GPS) motif, the molecular hallmark feature of the entire aGPCR class, is essential for LAT-1 signaling serving in two different activity modes of the receptor. Surprisingly, neither mode requires cleavage but presence of the GPS, which relays interactions with at least two different partners. Our work thus uncovers the versatile nature of aGPCR activity in molecular detail and places the GPS motif in a central position for diverse protein-protein interactions. PMID:22938866

Promel, Simone; Frickenhaus, Marie; Hughes, Samantha; Mestek, Lamia; Staunton, David; Woollard, Alison; Vakonakis, Ioannis; Schoneberg, Torsten; Schnabel, Ralf; Russ, Andreas P.; Langenhan, Tobias

2012-01-01

269

Structural Analysis of the Synaptic Protein Neuroligin and Its ?-Neurexin Complex: Determinants for Folding and Cell Adhesion  

PubMed Central

SUMMARY The neuroligins are postsynaptic cell adhesion proteins whose associations with presynaptic neurexins participate in synaptogenesis. Mutations in the neuroligin and neurexin genes appear to be associated with autism and mental retardation. The crystal structure of a neuroligin reveals features not found in its catalytically active relatives, such as the fully hydrophobic interface forming the functional neuroligin dimer; the conformations of surface loops surrounding the vestigial active center; the location of determinants that are critical for folding and processing; and the absence of a macromolecular dipole and presence of an electronegative, hydrophilic surface for neurexin binding. The structure of a ?-neurexin-neuroligin complex reveals the precise orientation of the bound neurexin and, despite a limited resolution, provides substantial information on the Ca2+-dependent interactions network involved in trans-synaptic neurexin-neuroligin association. These structures exemplify how an ?/?-hydrolase fold varies in surface topography to confer adhesion properties and provide templates for analyzing abnormal processing or recognition events associated with autism. PMID:18093521

Fabrichny, Igor P.; Leone, Philippe; Sulzenbacher, Gerlind; Comoletti, Davide; Miller, Meghan T.; Taylor, Palmer; Bourne, Yves; Marchot, Pascale

2009-01-01

270

Role of cGMP-dependent protein kinase in regulation of pulmonary vascular smooth muscle cell adhesion and migration: effect of hypoxia  

PubMed Central

Exposure to prolonged hypoxia can result in pulmonary vascular remodeling and pulmonary hypertension. Hypoxia induces pulmonary vascular smooth muscle cell (PVSMC) proliferation and vascular remodeling by affecting cell adhesion and migration and secretion of extracellular matrix proteins. We previously showed that acute hypoxia decreases cGMP-dependent protein kinase (PKG) activity in PVSMC and that PKG plays a role in maintaining the differentiated contractile phenotype in normoxia. In this study, we investigated the effect of hypoxia on PVSMC adhesion and migration and the role of PKG in these functions. Ovine fetal pulmonary artery SMC were incubated in normoxia (Po2 ?100 Torr) or hypoxia (Po2 ?30–40 Torr) or treated with the PKG inhibitor DT-3 for 24 h in normoxia. To further study the role of PKG in the modulation of adhesion and migration, PVSMC were transiently transfected with a full-length PKG1? [PKG-green fluorescent protein (GFP)] or a dominant-negative construct (G1?R-GFP). Cell adhesion to extracellular matrix proteins was determined, and integrin-mediated adhesion was assessed by ?/?-integrin-mediated cell adhesion array. Exposure to hypoxia (24 h) and pharmacological inhibition of PKG1 by DT-3 significantly promoted adhesion mediated by ?4-, ?1-, and ?5?1-integrins to fibronectin, laminin, and tenacin and also resulted in increased cell migration. Likewise, inhibition of PKG by expression of a dominant-negative PKG1? construct increased cell adhesion and migration, comparable to that induced by hypoxia. Dynamic actin reorganization associated with integrin-mediated cell adhesion is partly regulated by the actin-binding protein cofilin, the (Ser3) phosphorylation of which inhibits its actin-severing activity. We found that increased PKG expression and activity is associated with decreased cofilin (Ser3) phosphorylation, implying a role for PKG in the modulation of cofilin activity and actin dynamics. Together, these findings identify cGMP/PKG1 signaling as central to the functional differences between PVSMC exposed to normoxia versus hypoxia. PMID:19411288

Negash, S.; Narasimhan, S. R.; Zhou, W.; Liu, J.; Wei, F. L.; Tian, J.; Raj, J. Usha

2009-01-01

271

Biotin ligase tagging identifies proteins proximal to E-cadherin, including lipoma preferred partner, a regulator of epithelial cell-cell and cell-substrate adhesion.  

PubMed

Known proteins associated with the cell-adhesion protein E-cadherin include catenins and proteins involved in signaling, trafficking and actin organization. However, the list of identified adherens junction proteins is likely to be incomplete, limiting investigation into this essential cell structure. To expand the inventory of potentially relevant proteins, we expressed E-cadherin fused to biotin ligase in MDCK epithelial cells, and identified by mass spectrometry neighboring proteins that were biotinylated. The most abundant of the 303 proteins identified were catenins and nearly 40 others that had been previously reported to influence cadherin function. Many others could be rationalized as novel candidates for regulating the adherens junction, cytoskeleton, trafficking or signaling. We further characterized lipoma preferred partner (LPP), which is present at both cell contacts and focal adhesions. Knockdown of LPP demonstrated its requirement for E-cadherin-dependent adhesion and suggested that it plays a role in coordination of the cell-cell and cell-substrate cytoskeletal interactions. The analysis of LPP function demonstrates proof of principle that the proteomic analysis of E-cadherin proximal proteins expands the inventory of components and tools for understanding the function of E-cadherin. PMID:24338363

Van Itallie, Christina M; Tietgens, Amber Jean; Aponte, Angel; Fredriksson, Karin; Fanning, Alan S; Gucek, Marjan; Anderson, James M

2014-02-15

272

Comparative proteomic analysis of metabolically labelled proteins from Plasmodium falciparum isolates with different adhesion properties  

PubMed Central

The virulence of Plasmodium falciparum relates in part to the cytoadhesion characteristics of parasitized erythrocytes but the molecular basis of the different qualitative and quantitative binding phenotypes is incompletely understood. This paucity of information is due partly to the difficulty in working with membrane proteins, the variant nature of these surface antigens and their relatively low abundance. To address this two-dimensional (2D) protein profiles of closely related, but phenotypically different laboratory strains of P. falciparum have been characterized using proteomic approaches. Since the mature erythrocyte has no nucleus and no protein synthesis capability, metabolic labelling of proteins was used to selectively identify parasite proteins and increase detection sensitivity. A small number of changes (less than 10) were observed between four different P. falciparum laboratory strains with distinctive cytoadherence properties using metabolic labelling, with more parasite protein changes found in trophozoite iRBCs than ring stage. The combination of metabolic labelling and autoradiography can therefore be used to identify parasite protein differences, including quantitative ones, and in some cases to obtain protein identifications by mass spectrometry. The results support the suggestion that the membrane protein profile may be related to cytoadherent properties of the iRBCs. Most changes between parasite variants were differences in iso-electric point indicating differential protein modification rather than the presence or absence of a specific peptide. PMID:16887017

Wu, Yang; Craig, Alister

2006-01-01

273

Tyrosine Y189 in the Substrate Domain of the Adhesion Docking Protein NEDD9 Is Conserved with p130Cas Y253 and Regulates NEDD9-Mediated Migration and Focal Adhesion Dynamics  

PubMed Central

The focal adhesion docking protein NEDD9/HEF1/Cas-L regulates cell migration and cancer invasion. NEDD9 is a member of the Cas family of proteins that share conserved overall protein-protein interaction domain structure, including a substrate domain that is characterized by extensive tyrosine (Y) phosphorylation. Previous studies have suggested that phosphorylation of Y253 in the substrate domain of the Cas family protein p130Cas is specifically required for p130Cas function in cell migration. While it is clear that tyrosine phosphorylation of the NEDD9 substrate domain is similarly required for the regulation of cell motility, whether individual NEDD9 tyrosine residues have discrete function in regulating motility has not previously been reported. In the present study we have used a global sequence alignment of Cas family proteins to identify a putative NEDD9 equivalent of p130Cas Y253. We find that NEDD9 Y189 aligns with p130Cas Y253 and that it is conserved among NEDD9 vertebrate orthologues. Expression of NEDD9 in which Y189 is mutated to phenylalanine results in increased rates of cell migration and is correlated with increased disassembly of GFP.NEDD9 focal adhesions. Conversely, mutation to Y189D significantly inhibits cell migration. Our previous data has suggested that NEDD9 stabilizes focal adhesions and the present data therefore suggests that phosphorylation of Y189 NEDD9 is required for this function. These findings indicate that the individual tyrosine residues of the NEDD9 substrate domain may serve discrete functional roles. Given the important role of this protein in promoting cancer invasion, greater understanding of the function of the individual tyrosine residues is important for the future design of approaches to target NEDD9 to arrest cancer cell invasion. PMID:23874939

Baquiran, Jaime B.; Bradbury, Peta; O'Neill, Geraldine M.

2013-01-01

274

Heat shock protein 90? stabilizes focal adhesion kinase and enhances cell migration and invasion in breast cancer cells.  

PubMed

Focal adhesion kinase (FAK) acts as a regulator of cellular signaling and may promote cell spreading, motility, invasion and survival in malignancy. Elevated expression and activity of FAK frequently correlate with tumor cell metastasis and poor prognosis in breast cancer. However, the mechanisms by which the turnover of FAK is regulated remain elusive. Here we report that heat shock protein 90? (HSP90?) interacts with FAK and the middle domain (amino acids 233-620) of HSP90? is mainly responsible for this interaction. Furthermore, we found that HSP90? regulates FAK stability since HSP90? inhibitor 17-AAG triggers FAK ubiquitylation and subsequent proteasome-dependent degradation. Moreover, disrupted FAK-HSP90? interaction induced by 17-AAG contributes to attenuation of tumor cell growth, migration, and invasion. Together, our results reveal how HSP90? regulates FAK stability and identifies a potential therapeutic strategy to breast cancer. PMID:24880126

Xiong, Xiangyang; Wang, Yao; Liu, Chengmei; Lu, Quqin; Liu, Tao; Chen, Guoan; Rao, Hai; Luo, Shiwen

2014-08-01

275

Tissue adhesives and sealants  

Microsoft Academic Search

Rapid and secure tissue adherence using adhesives or sealants is an attractive concept. Cyanoacrylates, marine adhesive proteins, fibrin-based sealants, and mixtures of polypeptides and proteoglycans to form “laser solders” are just some of the products and technologies that have been used. Effectiveness, ease of use, cost, strength, degradation, safety, and toxicity are major concerns in seeking an ideal product. Thomas

Alan H. Gold

2003-01-01

276

The adhesion protein IgSF9b is coupled to neuroligin 2 via S-SCAM to promote inhibitory synapse development  

PubMed Central

Synaptic adhesion molecules regulate diverse aspects of synapse formation and maintenance. Many known synaptic adhesion molecules localize at excitatory synapses, whereas relatively little is known about inhibitory synaptic adhesion molecules. Here we report that IgSF9b is a novel, brain-specific, homophilic adhesion molecule that is strongly expressed in GABAergic interneurons. IgSF9b was preferentially localized at inhibitory synapses in cultured rat hippocampal and cortical interneurons and was required for the development of inhibitory synapses onto interneurons. IgSF9b formed a subsynaptic domain distinct from the GABAA receptor– and gephyrin-containing domain, as indicated by super-resolution imaging. IgSF9b was linked to neuroligin 2, an inhibitory synaptic adhesion molecule coupled to gephyrin, via the multi-PDZ protein S-SCAM. IgSF9b and neuroligin 2 could reciprocally cluster each other. These results suggest a novel mode of inhibitory synaptic organization in which two subsynaptic domains, one containing IgSF9b for synaptic adhesion and the other containing gephyrin and GABAA receptors for synaptic transmission, are interconnected through S-SCAM and neuroligin 2. PMID:23751499

Woo, Jooyeon; Kwon, Seok-Kyu; Nam, Jungyong; Choi, Seungwon; Takahashi, Hideto; Krueger, Dilja; Park, Joohyun; Lee, Yeunkum; Bae, Jin Young; Lee, Dongmin; Ko, Jaewon; Kim, Hyun; Kim, Myoung-Hwan; Bae, Yong Chul; Chang, Sunghoe

2013-01-01

277

The adhesion protein IgSF9b is coupled to neuroligin 2 via S-SCAM to promote inhibitory synapse development.  

PubMed

Synaptic adhesion molecules regulate diverse aspects of synapse formation and maintenance. Many known synaptic adhesion molecules localize at excitatory synapses, whereas relatively little is known about inhibitory synaptic adhesion molecules. Here we report that IgSF9b is a novel, brain-specific, homophilic adhesion molecule that is strongly expressed in GABAergic interneurons. IgSF9b was preferentially localized at inhibitory synapses in cultured rat hippocampal and cortical interneurons and was required for the development of inhibitory synapses onto interneurons. IgSF9b formed a subsynaptic domain distinct from the GABAA receptor- and gephyrin-containing domain, as indicated by super-resolution imaging. IgSF9b was linked to neuroligin 2, an inhibitory synaptic adhesion molecule coupled to gephyrin, via the multi-PDZ protein S-SCAM. IgSF9b and neuroligin 2 could reciprocally cluster each other. These results suggest a novel mode of inhibitory synaptic organization in which two subsynaptic domains, one containing IgSF9b for synaptic adhesion and the other containing gephyrin and GABAA receptors for synaptic transmission, are interconnected through S-SCAM and neuroligin 2. PMID:23751499

Woo, Jooyeon; Kwon, Seok-Kyu; Nam, Jungyong; Choi, Seungwon; Takahashi, Hideto; Krueger, Dilja; Park, Joohyun; Lee, Yeunkum; Bae, Jin Young; Lee, Dongmin; Ko, Jaewon; Kim, Hyun; Kim, Myoung-Hwan; Bae, Yong Chul; Chang, Sunghoe; Craig, Ann Marie; Kim, Eunjoon

2013-06-10

278

Molecular Cloning and Characterization of a Surface-Localized Adhesion Protein in Mycoplasma bovis Hubei-1 Strain  

PubMed Central

Mycoplasma bovis (M. bovis) is an important pathogen that causes various bovine diseases, such as mastitis in cows and pneumonia in calves. The surface proteins are generally thought to play a central role in the pathogenesis of this organism. We screened the entire genome of M. bovis Hubei-1 and discovered a gene named vpmaX that encodes the 25 kDa variable surface lipoprotein A (VpmaX). Sequence analysis revealed that VpmaX contains several repetitive units and a typical bacterial lipoprotein signal sequence. The vpmaX gene was cloned and expressed in E. coli to obtain recombinant VpmaX (rVpmaX). Western blot analysis using a rabbit antibody against rVpmaX demonstrated that VpmaX is a membrane protein. Immunostaining visualized via confocal laser scanning microscopy showed that rVpmaX was able to adhere to embryonic bovine lung cells (EBL), and this was also confirmed by a sandwich ELISA. In summary, a surface-localized adhesion protein was identified in M. bovis Hubei-1. PMID:23936063

Wang, Yang; Zhou, Yumei; Liu, Yang; Xin, Jiuqing

2013-01-01

279

The Adhesion of Plasmodium falciparum-Infected Erythrocytes to Chondroitin Sulfate A Is Mediated by P. falciparum Erythrocyte Membrane Protein 1  

Microsoft Academic Search

Chondroitin sulfate A (CSA) is an important receptor for the sequestration of Plasmodium falciparum in the placenta, but the parasite ligand involved in adhesion has not previously been identified. Here we report the identification of a var gene transcribed in association with binding to CSA and present evidence that the P. falciparum erythrocyte membrane protein 1 product of the gene

John C. Reeder; Alan F. Cowman; Kathleen M. Davern; James G. Beeson; Jennifer K. Thompson; Stephen J. Rogerson; Graham V. Brown

1999-01-01

280

A Novel Group of Moraxella catarrhalis UspA Proteins Mediates Cellular Adhesion via CEACAMs and Vitronectin  

PubMed Central

Moraxella catarrhalis (Mx) is a common cause of otitis media and exacerbation of chronic obstructive pulmonary disease, an increasing worldwide problem. Surface proteins UspA1 and UspA2 of Mx bind to a number of human receptors and may function in pathogenesis. Genetic recombination events in the pathogen can generate hybrid proteins termed UspA2H. However, whether certain key functions (e.g. UspA1-specific CEACAM binding) can be exchanged between these adhesin families remains unknown. In this study, we have shown that Mx can incorporate the UspA1 CEACAM1-binding region not only into rare UspA1 proteins devoid of CEACAM-binding ability, but also into UspA2 which normally lack this capacity. Further, a screen of Mx isolates revealed the presence of novel UspA2 Variant proteins (UspA2V) in ?14% of the CEACAM-binding population. We demonstrate that the expression of UspA2/2V with the CEACAM-binding domain enable Mx to bind both to cell surface CEACAMs and to integrins, the latter via vitronectin. Such properties of UspA2/2V have not been reported to date. The studies demonstrate that the UspA family is much more heterogeneous than previously believed and illustrate the in vivo potential for exchange of functional regions between UspA proteins which could convey novel adhesive functions whilst enhancing immune evasion. PMID:23049802

Hill, Darryl J.; Whittles, Cheryl; Virji, Mumtaz

2012-01-01

281

'Special k' and a loss of cell-to-cell adhesion in proximal tubule-derived epithelial cells: modulation of the adherens junction complex by ketamine.  

PubMed

Ketamine, a mild hallucinogenic class C drug, is the fastest growing 'party drug' used by 16-24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24-48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1-1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and ?-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGF?, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention. PMID:24009666

Hills, Claire E; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P; Squires, Paul E

2013-01-01

282

Hybrid GPCR\\/Cadherin (Celsr) Proteins in Rat Testis Are Expressed With Cell Type Specificity and Exhibit Differential Sertoli Cell-Germ Cell Adhesion Activity  

Microsoft Academic Search

Spermatogenesis requires Sertoli cell-germ cell ad- hesion for germ cell survival and maturation. Cadherins are a diverse superfamily of adhesion proteins; structurally unique members of this superfamily (celsr cadherins) are hybrid molecules containing extra- cellular cadherin repeats connected to a G protein-coupled receptor transmembrane motif. Here we demonstrate postnatal testicular mRNA expression of the 3 celsr paralogs (celsr1, celsr2, and

STEPHANIE A. BEALL; KIM BOEKELHEIDE; KAMIN J. JOHNSON

2005-01-01

283

Adhesive protein-free synthetic hydrogels for retinal pigment epithelium cell culture with low ROS level.  

PubMed

Engineering of human retinal pigment epithelium (RPE) cell monolayer with low level of reactive oxygen species (ROS) is important for regenerative RPE-based therapies. However, it is still challenging to culture RPE monolayer with low ROS level on soft substrates in vitro. To address this, we developed cytocompatible hydrogels to culture human RPE cell monolayer for future use in regenerative RPE-based therapies. The cell adhesion, proliferation, monolayer formation, morphology, survival, and ROS level of human ARPE-19 cells cultured on the surfaces of negatively charged poly (2-acrylamido-2-methyl propane sulfonic sodium) (PNaAMPS) and neutral poly(N,N-dimethylacrylamide) (PDMAAm) hydrogels with different stiffness were investigated. The importance of hydrogel stiffness on the cell function was firstly highlighted on the base of determined optimal Young's modulus for cultivation of RPE cell monolayer with relatively low ROS level. The construction of RPE cell monolayer with low ROS level on the PNaAMPS hydrogel may hold great potential as promising candidates for transplantation of RPE cell monolayer-hydrogel construct into the subretinal space to repair retinal functions. PMID:23913900

Chen, Yong Mei; Liu, Zhen Qi; Feng, Zhi Hui; Xu, Feng; Liu, Jian Kang

2014-07-01

284

Tumor Necrosis Factor Induces Early-Onset Endothelial Adhesivity by Protein Kinase C-Dependent Activation of Intercellular Adhesion Molecule1  

Microsoft Academic Search

We tested the hypothesis that TNF- induces early-onset endothelial adhesivity toward PMN by activating the constitutive endothelial cell surface ICAM-1, the 2-integrin (CD11\\/CD18) counter-receptor. Stimulation of human pulmonary artery endothelial cells with TNF- resulted in phosphorylation of ICAM-1 within 1 minute, a response that was sustained up to 15 minutes after TNF- challenge. We observed that TNF- induced 10-fold increase

Kamran Javaid; Arshad Rahman; Khandaker N. Anwar; Randall S. Frey; Richard D. Minshall; Asrar B. Malik

285

Cell adhesion and sorting in embryoid bodies derived from N- or E-cadherin deficient murine embryonic stem cells.  

PubMed

The primitive endoderm epithelial structure in mouse blastocysts forms following cell differentiation and subsequent sorting, and this two-step process can be reproduced in vitro using an embryoid body model. We found that in the chimeric embryoid bodies consisting of paired wildtype and E-cadherin null ES cells, the wildtype sorted to the center and were enveloped by the less adhesive E-cadherin null cells, in accord with Steinberg's hypothesis. However, wildtype and N-cadherin null ES cells intermixed and did not segregate, a situation that may be explained by Albert Harris' modified principle, which incorporates the unique properties of living cells. Furthermore, in chimeric embryoid bodies composed of N-cadherin and E-cadherin null ES cells, the two weakly interacting cell types segregated but did not envelop one another. Lastly, the most consistent and striking observation was that differentiated cells sorted to the surface and formed an enveloping layer, regardless of the relative cell adhesive affinity of any cell combination, supporting the hypothesis that the ability of the differentiated cells to establish apical polarity is the determining factor in surface sorting and positioning. PMID:24414205

Moore, Robert; Tao, Wensi; Meng, Yue; Smith, Elizabeth R; Xu, Xiang-Xi

2014-01-01

286

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

287

Cell adhesion and cortex contractility determine cell patterning in the Drosophila retina.  

PubMed

Because of the resemblance of many epithelial tissues to densely packed soap bubbles, it has been suggested that surface minimization, which drives soap bubble packing, could be governing cell packing as well. We test this by modeling the shape of the cells in a Drosophila retina ommatidium. We use the observed configurations and shapes in wild-type flies, as well as in flies with different numbers of cells per ommatidia, and mutants with cells where E- or N-cadherin is either deleted or misexpressed. We find that surface minimization is insufficient to model the experimentally observed shapes and packing of the cells based on their cadherin expression. We then consider a model in which adhesion leads to a surface increase, balanced by cell cortex contraction. Using the experimentally observed distributions of E- and N-cadherin, we simulate the packing and cell shapes in the wild-type eye. Furthermore, by changing only the corresponding parameters, this model can describe the mutants with different numbers of cells or changes in cadherin expression. PMID:18003929

Käfer, Jos; Hayashi, Takashi; Marée, Athanasius F M; Carthew, Richard W; Graner, François

2007-11-20

288

In-depth Characterization of the Secretome of Colorectal Cancer Metastatic Cells Identifies Key Proteins in Cell Adhesion, Migration, and Invasion*  

PubMed Central

Liver metastasis in colorectal cancer is the major cause of cancer-related deaths. To identify and characterize proteins associated with colon cancer metastasis, we have compared the conditioned serum-free medium of highly metastatic KM12SM colorectal cancer cells with the parental, poorly metastatic KM12C cells using quantitative stable isotope labeling by amino acids in cell culture (SILAC) analyses on a linear ion trap-Orbitrap Velos mass spectrometer. In total, 1337 proteins were simultaneously identified in SILAC forward and reverse experiments. For quantification, 1098 proteins were selected in both experiments, with 155 proteins showing >1.5-fold change. About 52% of these proteins were secreted directly or using alternative secretion pathways. GDF15, S100A8/A9, and SERPINI1 showed capacity to discriminate cancer serum samples from healthy controls using ELISAs. In silico analyses of deregulated proteins in the secretome of metastatic cells showed a major abundance of proteins involved in cell adhesion, migration, and invasion. To characterize the tumorigenic and metastatic properties of some top up- and down-regulated proteins, we used siRNA silencing and antibody blocking. Knockdown expression of NEO1, SERPINI1, and PODXL showed a significant effect on cellular adhesion. Silencing or blocking experiments with SOSTDC1, CTSS, EFNA3, CD137L/TNFSF9, ZG16B, and Midkine caused a significant decrease in migration and invasion of highly metastatic cells. In addition, silencing of SOSTDC1, EFNA3, and CD137L/TNFSF9 reduced liver colonization capacity of KM12SM cells. Finally, the panel of six proteins involved in invasion showed association with poor prognosis and overall survival after dataset analysis of gene alterations. In summary, we have defined a collection of proteins that are relevant for understanding the mechanisms underlying adhesion, migration, invasion, and metastasis in colorectal cancer. PMID:23443137

Barderas, Rodrigo; Mendes, Marta; Torres, Sofia; Bartolome, Ruben A.; Lopez-Lucendo, Maria; Villar-Vazquez, Roi; Pelaez-Garcia, Alberto; Fuente, Eduardo; Bonilla, Felix; Casal, J. Ignacio

2013-01-01

289

Engineering protein and cell adhesivity using PEO-terminated triblock polymers  

E-print Network

to a variety of common surfaces including tissue culture polystyrene, methylated glass, silicone modification include photolithographic pat- terning of glass and subsequent silane/protein immo- bilization,6 have used vari- ous methods to immobilize nonadhesive PEO-based poly- mers on surfaces to inhibit

Bhatia, Sangeeta

290

Nanoscale dynamics and protein adhesivity of alkylamine self-assembled monolayers on graphene.  

PubMed

Atomic-scale molecular dynamics computer simulations are used to probe the structure, dynamics, and energetics of alkylamine self-assembled monolayer (SAM) films on graphene and to model the formation of molecular bilayers and protein complexes on the films. Routes toward the development and exploitation of functionalized graphene structures are detailed here, and we show that the SAM architecture can be tailored for use in emerging applications (e.g., electrically stimulated nerve fiber growth via the targeted binding of specific cell surface peptide sequences on the functionalized graphene scaffold). The simulations quantify the changes in film physisorption on graphene and the alkyl chain packing efficiency as the film surface is made more polar by changing the terminal groups from methyl (-CH3) to amine (-NH2) to hydroxyl (-OH). The mode of molecule packing dictates the orientation and spacing between terminal groups on the surface of the SAM, which determines the way in which successive layers build up on the surface, whether via the formation of bilayers of the molecule or the immobilization of other (macro)molecules (e.g., proteins) on the SAM. The simulations show the formation of ordered, stable assemblies of monolayers and bilayers of decylamine-based molecules on graphene. These films can serve as protein adsorption platforms, with a hydrophobin protein showing strong and selective adsorption by binding via its hydrophobic patch to methyl-terminated films and binding to amine-terminated films using its more hydrophilic surface regions. Design rules obtained from modeling the atomic-scale structure of the films and interfaces may provide input into experiments for the rational design of assemblies in which the electronic, physicochemical, and mechanical properties of the substrate, film, and protein layer can be tuned to provide the desired functionality. PMID:23301836

O'Mahony, S; O'Dwyer, C; Nijhuis, C A; Greer, J C; Quinn, A J; Thompson, D

2013-06-18

291

The Ras suppressor Rsu-1 binds to the LIM 5 domain of the adaptor protein PINCH1 and participates in adhesion-related functions.  

PubMed

Rsu-1 is a highly conserved leucine rich repeat (LRR) protein that is expressed ubiquitously in mammalian cells. Rsu-1 was identified based on its ability to inhibit transformation by Ras, and previous studies demonstrated that ectopic expression of Rsu-1 inhibited anchorage-independent growth of Ras-transformed cells and human tumor cell lines. Using GAL4-based yeast two-hybrid screening, the LIM domain protein, PINCH1, was identified as the binding partner of Rsu-1. PINCH1 is an adaptor protein that localizes to focal adhesions and it has been implicated in the regulation of adhesion functions. Subdomain mapping in yeast revealed that Rsu-1 binds to the LIM 5 domain of PINCH1, a region not previously identified as a specific binding domain for any other protein. Additional testing demonstrated that PINCH2, which is highly homologous to PINCH1, except in the LIM 5 domain, does not interact with Rsu-1. Glutathione transferase fusion protein binding studies determined that the LRR region of Rsu-1 interacts with PINCH1. Transient expression studies using epitope-tagged Rsu-1 and PINCH1 revealed that Rsu-1 co-immunoprecipitated with PINCH1 and colocalized with vinculin at sites of focal adhesions in mammalian cells. In addition, endogenous P33 Rsu-1 from 293T cells co-immunoprecipitated with transiently expressed myc-tagged PINCH1. Furthermore, RNAi-induced reduction in Rsu-1 RNA and protein inhibited cell attachment, and while previous studies demonstrated that ectopic expression of Rsu-1 inhibited Jun kinase activation, the depletion of Rsu-1 resulted in activation of Jun and p38 stress kinases. These studies demonstrate that Rsu-1 interacts with PINCH1 in mammalian cells and functions, in part, by altering cell adhesion. PMID:15878342

Dougherty, Gerard W; Chopp, Treasa; Qi, Sheng-Mei; Cutler, Mary Lou

2005-05-15

292

Interaction of Ubinuclein-1, a nuclear and adhesion junction protein, with the 14-3-3 epsilon protein in epithelial cells: implication of the PKA pathway.  

PubMed

Ubinuclein-1 is a NACos (Nuclear and Adhesion junction Complex components) protein which shuttles between the nucleus and tight junctions, but its function in the latter is not understood. Here, by co-immunoprecipitation and confocal analysis, we show that Ubinuclein-1 interacts with the 14-3-3? protein both in HT29 colon cells, and AGS gastric cells. This interaction is mediated by an Ubinuclein-1 phosphoserine motif. We show that the arginine residues (R56, R60 and R132) which form the 14-3-3? ligand binding site are responsible for the binding of 14-3-3? to phosphorylated Ubinuclein-1. Furthermore, we demonstrate that in vitro Ubinuclein-1 can be directly phosphorylated by cAMP-dependent protein kinase A. This in vitro phosphorylation allows binding of wildtype 14-3-3?. Moreover, treatment of the cells with inhibitors of the cAMP-dependent protein kinase, KT5720 or H89, modifies the subcellular localization of Ubinuclein-1. Indeed, KT5720 and H89 greatly increase the staining of Ubinuclein-1 at the tight junctions in AGS gastric cells. In the presence of the kinase inhibitor KT5720, the amount of Ubinuclein-1 in the NP40 insoluble fraction is increased, together with actin. Moreover, treatment of the cells with KT5720 or H89 induces the concentration of Ubinuclein-1 at tricellular intersections of MDCK cells. Taken together, our findings demonstrate novel cell signaling trafficking by Ubinuclein-1 via association with 14-3-3? following Ubinuclein-1 phosphorylation by the cAMP-dependent protein kinase-A. PMID:23395486

Conti, Audrey; Sueur, Charlotte; Lupo, Julien; Brazzolotto, Xavier; Burmeister, Wim P; Manet, Evelyne; Gruffat, Henri; Morand, Patrice; Boyer, Véronique

2013-03-01

293

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

294

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; Luder, Carsten G. K.; Zautner, Andreas E.; Gross, Uwe; Heimesaat, Markus M.; Bereswill, Stefan; Lugert, Raimond

2013-01-01

295

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

296

Influence of poly(ethylene oxide)-based copolymer on protein adsorption and bacterial adhesion on stainless steel: modulation by surface hydrophobicity.  

PubMed

The aim of the present work is to study the adhesion of Pseudomonas NCIMB 2021, a typical aerobic marine microorganism, on stainless steel (SS) substrate. More particularly, the potential effect on adhesion of adsorbed poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer is investigated. Bacterial attachment experiments were carried out using a modified parallel plate flow chamber, allowing different surface treatments to be compared in a single experiment. The amount of adhering bacteria was determined via DAPI staining and fluorescence microscopy. X-ray photoelectron spectroscopy (XPS) was used to characterize the surface chemical composition of SS and hydrophobized SS before and after PEO-PPO-PEO adsorption. The adsorption of bovine serum albumin (BSA), a model protein, was investigated to test the resistance of PEO-PPO-PEO layers to protein adsorption. The results show that BSA adsorption and Pseudomonas 2021 adhesion are significantly reduced on hydrophobized SS conditioned with PEO-PPO-PEO. Although PEO-PPO-PEO is also found to adsorb on SS, it does not prevent BSA adsorption nor bacterial adhesion, which is attributed to different PEO-PPO-PEO adlayer structures on hydrophobic and hydrophilic surfaces. The obtained results open the way to a new strategy to reduce biofouling on metal oxide surfaces using PEO-PPO-PEO triblock copolymer. PMID:24650936

Yang, Yi; Rouxhet, Paul G; Chudziak, Dorota; Telegdi, Judit; Dupont-Gillain, Christine C

2014-06-01

297

Protein adsorption and cell adhesion on three-dimensional polycaprolactone scaffolds with respect to plasma modification by etching and deposition techniques  

NASA Astrophysics Data System (ADS)

In this work, protein adsorption and cell adhesion on three-dimensional (3D) polycaprolactone (PCL) scaffolds treated by plasma etching and deposition were performed. The 3D PCL scaffold used as a substrate of a bone tissue was fabricated by recent rapid prototype techniques. To increase surface properties, such as hydrophilicity, roughness, and surface chemistry, through good protein adhesion on scaffolds, oxygen (O2) plasma etching and acrylic acid or allyamine plasma deposition were performed on the 3D PCL scaffolds. The O2 plasma etching induced the formation of random nanoporous structures on the roughened surfaces of the 3D PCL scaffolds. The plasma deposition with acrylic acid and allyamine induced the chemical modification for introducing a functional group. The protein adsorption increased on the O2 plasma-etched surface compared with an untreated 3D PCL scaffold. MC3T3-E1 cells adhered bioactively on the etched and deposited surface compared with the untreated surface. The present plasma modification might be sought as an effective technique for enhancing protein adsorption and cell adhesion.

Myung, Sung Woon; Ko, Yeong Mu; Kim, Byung Hoon

2014-11-01

298

A hybrid total internal reflection fluorescence and optical tweezers microscope to study cell adhesion and membrane protein dynamics of single living cells.  

PubMed

The dynamics of cell surface membrane proteins plays an important role in cell-cell interactions. The onset of the interaction is typically not precisely controlled by current techniques, making especially difficult the visualization of early-stage dynamics. We have developed a novel method where optical tweezers are used to trap cells and precisely control in space and time the initiation of interactions between a cell and a functionalized surface. This approach is combined with total internal reflection fluorescence microscopy to monitor dynamics of membrane bound proteins. We demonstrate an accuracy of approximately 2 s in determining the onset of the interaction. Furthermore, we developed a data analysis method to determine the dynamics of cell adhesion and the organization of membrane molecules at the contact area. We demonstrate and validate this approach by studying the dynamics of the green fluorescent protein tagged membrane protein activated leukocyte cell adhesion molecule expressed in K562 cells upon interaction with its ligand CD6 immobilized on a coated substrate. The measured cell spreading is in excellent agreement with existing theoretical models. Active redistribution of activated leukocyte cell adhesion molecule is observed from a clustered to a more homogenous distribution upon contact initiation. This redistribution follows exponential decay behaviour with a characteristic time of 35 s. PMID:19196415

Snijder-Van As, M I; Rieger, B; Joosten, B; Subramaniam, V; Figdor, C G; Kanger, J S

2009-01-01

299

Assessing the Role of the Cadherin/Catenin Complex at the Schwann Cell-Axon Interface and in the Initiation of Myelination  

PubMed Central

Myelination is dependent on complex reciprocal interactions between the Schwann cell (SC) and axon. Recent evidence suggests that the SC–axon interface represents a membrane specialization essential for myelination; however, the manner in which this polarized-apical domain is generated remains a mystery. The cell adhesion molecule N-cadherin is enriched at the SC–axon interface and colocalizes with the polarity protein Par-3. The asymmetric localization is induced on SC–SC and SC–axon contact. Knockdown of N-cadherin in SCs cocultured with DRG neurons disrupts Par-3 localization and delays the initiation of myelination. However, knockdown or overexpression of neuronal N-cadherin does not influence the distribution of Par-3 or myelination, suggesting that homotypic interactions between SC and axonal N-cadherin are not essential for the events surrounding myelination. To further investigate the role of N-cadherin, mice displaying SC-specific gene ablation of N-cadherin were generated and characterized. Surprisingly, myelination is only slightly delayed, and mice are viable without any detectable myelination defects. ?-Catenin, a downstream effector of N-cadherin, colocalizes and coimmunoprecipitates with N-cadherin on the initiation of myelination. To determine whether ?-catenin mediates compensation on N-cadherin deletion, SC-specific gene ablation of ?-catenin was generated and characterized. Consistent with our hypothesis, myelination is more severely delayed than when manipulating N-cadherin alone, but without any defect to the myelin sheath. Together, our results suggest that N-cadherin interacts with ?-catenin in establishing SC polarity and the timely initiation of myelination, but they are nonessential components for the formation and maturation of the myelin sheath. PMID:21414924

Lewallen, Kathryn A.; Shen, Yun-An A.; De La Torre, Asia R.; Ng, Benjamin K.; Meijer, Dies

2011-01-01

300

A Comparative Study of Serum Level of Vascular Cell Adhesion Molecule-1 (sVCAM-1), Intercellular Adhesion Molecule-1(ICAM-1) and High Sensitive C - reactive protein (hs-CRP) in Normal and Pre-eclamptic Pregnancies  

PubMed Central

Objective(s): Pre-eclampsia is characterized by hypertension, dyslipidemia, and increased systemic inflammatory response and has been associated with an increased maternal risk of cardiovascular disease later in life. Endothelial dysfunction is thought to be a central pathogenic feature in pre-eclampsia on the basis of elevated adhesion molecules. The aim of this study was to determine the level of plasma serum level of vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1(ICAM-1), high sensitive C- reactive protein (hs-CRP) in pre-eclampsia and to compare hs-CRP levels between normal pregnant women, mild and severe pre-eclampsia. Materials and Methods : A cross-sectional study was conducted to determine the plasma concentrations of sVCAM-1, ICAM-1 and hs-CRP in peripheral blood obtained from normal pregnant women (n=40), mild pre-eclampsia (n=37) and severe pre-eclampsia (n=38). Concentrations of soluble adhesion molecule was determined with enzyme linked immunosorbent assay (ELISA). Results: There were significant difference in the means serum hs-CRP between normal pregnant women and mild pre-eclamptic women (P<0.05). Serum concentration of hs-CRP, sVCAM-1(ng.ml) and sICAM-1(ng.ml) were significantly higher in severe pre-eclampsia (P<0.05) than normal pregnancy. There were also significant differences in hs-CRP, s ICAM- 1 and in sVCAM- 1 levels between mild and severe pre-eclampsia (P<0.05). There was no difference in the mean plasma log sVCAM-1, sICAM-1 between normal pregnant women and mild pre-eclamptic women. Conclusion: We have determined the serum concentration of soluble adhesion molecule ICAM-1, VCAM-1 and hsCRP in normal pregnancy and pre-eclampsia. Adhesion molecule is elevated in severe pre-eclampsia compared with normal pregnancy, hsCRP are elevated in severe preeclampsia compared with mild preeclampsia and normal pregnancy and may be useful in predicting the severity of pre-eclampsia. PMID:23826490

Farzadnia, Mehdi; Ayatollahi, Hossein; Hasan-zade, Maliheh; Rahimi, Hamid Reza

2013-01-01

301

Cadherin adhesion and mechanotransduction.  

PubMed

Cadherins are the principal adhesion proteins at intercellular junctions and function as the biochemical Velcro that binds cells together. Besides this mechanical function, cadherin complexes are also mechanotransducers that sense changes in tension and trigger adaptive reinforcement of intercellular junctions. The assembly and regulation of cadherin adhesions are central to their mechanical functions, and new evidence is presented for a comprehensive model of cadherin adhesion, which is surprisingly more complex than previously appreciated. Recent findings also shed new light on mechanisms that regulate cadherin junction assembly, adhesion, and mechanotransduction. We further describe recent evidence for cadherin-based mechanotransduction, and the rudiments of the molecular mechanism, which involves ?-catenin and vinculin as key elements. Potential roles of a broader cast of possible force-sensitive partners are considered, as well as known and speculative biological consequences of adhesion and force transduction at cadherin-mediated junctions. PMID:25062360

Leckband, D E; de Rooij, J

2014-10-11

302

Neurite outgrowth triggered by the cell adhesion molecule L1 requires activation and inactivation of the cytoskeletal protein cofilin.  

PubMed

Neurite outgrowth, an essential process for constructing nervous system connectivity, requires molecular cues which promote neurite extension and guide growing neurites. The neural cell adhesion molecule L1 is one of the molecules involved in this process. Growth of neurites depends on actin remodeling, but actin-remodeling proteins which act downstream of L1 signaling are not known. In this study, we investigated whether the actin-remodeling protein cofilin, which can be activated by dephosphorylation, is involved in neurite outgrowth stimulated by L1. Upon stimulation with an L1 monoclonal antibody which specifically triggers L1-dependent neurite outgrowth, cofilin phosphorylation in cultured cerebellar granule neurons and isolated growth cones was reduced to 47 ± 13% or 58 ± 9% of IgG control levels, respectively. We therefore investigated whether cofilin phosphorylation plays a role in L1-stimulated neurite outgrowth. Inhibition of calcineurin, a phosphatase acting upstream of cofilin dephosphorylation, impaired L1-dependent neurite extension in cultures of cerebellar granule neurons and led to an increase in cofilin phosphorylation. Moreover, when peptide S3, a competitive inhibitor of cofilin phosphorylation, or peptide pS3, a competitive inhibitor of cofilin dephosphorylation, were transferred into cerebellar neurons in culture, L1-stimulated neurite outgrowth was reduced from 173 ± 15% to 103 ± 4% of poly-L-lysine control levels in the presence of either peptide. Our findings suggest that both activation of cofilin by dephosphorylation and inactivation of cofilin by phosphorylation are essential for L1-stimulated neurite outgrowth. These results are in accordance with a cofilin activity cycle recently proposed for invasive tumor cells and inflammatory cells, indicating that a similar regulatory mechanism might be involved in neurite outgrowth. As L1 is expressed by invasive tumor cells, cofilin might also be a downstream actor of L1 in metastasis. PMID:22019611

Figge, Carina; Loers, Gabriele; Schachner, Melitta; Tilling, Thomas

2012-02-01

303

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

304

Polyphosphoprotein-Containing Marine Adhesives  

Microsoft Academic Search

Protein phosphorylation is an important regulator of both cellular and extracellular events. Recently, protein phosphorylation has also emerged as an important process in biological adhesives. During the last decade, Herbert Waite and his group have indeed characterized several polyphosphoproteins from the adhesive secretions of two different marine organisms, mussels and tube-building worms. This suggests the possibility that polyphosphoproteins could be

Patrick Flammang; Aurélie Lambert; Philippe Bailly; Elise Hennebert

2009-01-01

305

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

306

Epidemiological survey of Babesia gibsoni infection in dogs in Japan by enzyme-linked immunosorbent assay using B. gibsoni thrombospondin-related adhesive protein antigen  

Microsoft Academic Search

A nationwide epidemiological survey of Babesia gibsoni infection in non-fighting dogs was conducted using an improved ELISA with recombinant B. gibsoni thrombospondin-related adhesive protein (BgTRAP). A total of 1206 dogs from 27 prefectures were examined and 128 (10.6%) tested positive. In the eastern part of Japan, 39 dogs out of the 559 (7.0%) examined were positive, while 89 dogs out

Kenji Konishi; Yoshimi Sakata; Naomi Miyazaki; Honglin Jia; Youn-Kyoung Goo; Xuenan Xuan; Hisashi Inokuma

2008-01-01

307

Ag-ELISA and PCR for Monitoring the Vaccination of Cattle against Taenia saginata Cysticercosis Using an Oncospheral Adhesion Protein (HP6) with Surface and Secreted Localization  

Microsoft Academic Search

ATaenia saginata oncosphere-derived adhesion protein (HP6) with surface and secreted localization was used to successfully vaccinate calves against oral challenge withT. saginata eggs. In contrast, vaccination using a combination ofT. saginata oncosphere-derived peptides, selected on the basis of their antigenic index, and including three derived from the HP6 molecule (HP6-1, HP6-2 and HP6-3), was unsuccessful. This either indicated that the

L. J. S. Harrison; T. Garate; D. M. Bryce; L. M. Gonzalez; M. Foster-Cuevas; L. W. Wamae; J. A. Onyango-Abuje; R. M. E. Parkhouse

2005-01-01

308

Interactions of the chondroitin sulfate proteoglycan phosphacan, the extracellular domain of a receptor-type protein tyrosine phosphatase, with neurons, glia, and neural cell adhesion molecules  

Microsoft Academic Search

Phosphacan is a chondroitin sulfate pro- teoglycan produced by glial cells in the central ner- vous system, and represents the extracellular domain of a receptor-type protein tyrosine phosphatase (RPTPg'\\/B). We previously demonstrated that soluble phosphacan inhibited the aggregation of microbeads coated with N-CAM or Ng-CAM, and have now found that soluble ~25I-phosphacan bound reversibly to these neural cell adhesion molecules,

Peter Milev; David R. Friedlander; Takeshi Sakurai; Laina Karthikeyan; Manuela Flad; K. Margolis; Martin Grumet; Richard U. Margolis

1994-01-01

309

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

310

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

311

Glyceraldehyde-3-phosphate dehydrogenase, an immunogenic Streptococcus equi ssp. zooepidemicus adhesion protein and protective antigen.  

PubMed

Streptococcus equi ssp. zooepidemicus (Streptococcus zooepidemicus, SEZ) is an important pathogen associated with opportunistic infections of a wide range of species, including pigs and humans. The absence of a suitable vaccine makes it difficult to control SEZ infection. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been previously identified as an immunogenic protein using immunoproteomic techniques. In the present study, we confirmed that the sequence of GAPDH was highly conserved with other Streptococcus spp. The purified recombinant GAPDH could elicit a significant humoral antibody response in mice and confer significant protection against challenge with a lethal dose of SEZ. GAPDH could adhere to the Hep-2 cells, confirmed by flow cytometry, and inhibit adherence of SEZ to Hep-2 cells in an adherence inhibition assay. In addition, real-time PCR demonstrated that GAPDH was induced in vivo following infection of mice with SEZ. These suggest that GAPDH could play an important role in the pathogenesis of SEZ infection and could be a target for vaccination against SEZ. PMID:23568215

Fu, Qiang; Wei, Zigong; Liu, Xiaohong; Xiao, Pingping; Lu, Zhaohui; Chen, Yaosheng

2013-04-01

312

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

313

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

314

Over-expression of mitogen-activated protein kinase phosphatase-2 enhances adhesion molecule expression and protects against apoptosis in human endothelial cells  

PubMed Central

BACKGROUND AND PURPOSE We assessed the effects of over-expressing the dual-specific phosphatase, mitogen-activated protein (MAP) kinase phosphatase-2 (MKP-2), in human umbilical vein endothelial cells (HUVECs) on inflammatory protein expression and apoptosis, two key features of endothelial dysfunction in disease. EXPERIMENTAL APPROACHES We infected HUVECs for 40 h with an adenoviral version of MKP-2 (Adv.MKP-2). Tumour necrosis factor (TNF)-?-stimulated phosphorylation of MAP kinase and protein expression was measured by Western blotting. Cellular apoptosis was assayed by FACS. KEY RESULTS Infection with Adv.MKP-2 selectively abolished TNF-?-mediated c-Jun-N-terminal kinase (JNK) activation and had little effect upon extracellular signal-regulated kinase or p38 MAP kinase. Adv.MKP-2 abolished COX-2 expression, while induction of the endothelial cell adhesion molecules, intercellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM), two NF?B-dependent proteins, was not affected. However, when ICAM and VCAM expression was partly reduced by blockade of the NF?B pathway, Adv.MKP-2 was able to reverse this inhibition. This correlated with enhanced TNF-?-induced loss of the inhibitor of ?B (I?B)? loss, a marker of NF?B activation. TNF-? in combination with NF?B blockade also increased HUVEC apoptosis; this was significantly reversed by Adv.MKP-2. Protein markers of cellular damage and apoptosis, H2AX phosphorylation and caspase-3 cleavage, were also reversed by MKP-2 over-expression. CONCLUSIONS AND IMPLICATIONS Over-expression of MKP-2 had different effects upon the expression of inflammatory proteins due to a reciprocal effect upon JNK and NF?B signalling, and also prevented TNF-?-mediated endothelial cell death. These properties may make Adv.MKP-2 a potentially useful future therapy in cardiovascular diseases where endothelial dysfunction is a feature. PMID:20860659

Al-Mutairi, Mashael; Al-Harthi, Sameer; Cadalbert, Laurence; Plevin, Robin

2010-01-01

315

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

316

Candida albicans uses the surface protein Gpm1 to attach to human endothelial cells and to keratinocytes via the adhesive protein vitronectin.  

PubMed

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 Gpm1 when 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

317

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

318

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, Gregory; Chauvel, Muriel; Sautour, Marc; Bougnoux, Marie-Elisabeth; Bellon-Fontaine, Marie-Noelle; Dalle, Frederic; d'Enfert, Christophe; Richard, Mathias L.

2013-01-01

319

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

320

Acute Activation of ?2-Adrenergic Receptor Regulates Focal Adhesions through ?Arrestin2- and p115RhoGEF Protein-mediated Activation of RhoA*  

PubMed Central

?2-Adrenergic receptors (?2ARs) regulate cellular functions through G protein-transduced and ?Arrestin-transduced signals. ?2ARs have been shown to regulate cancer cell migration, but the underlying mechanisms are not well understood. Here, we report that ?2AR regulates formation of focal adhesions, whose dynamic remodeling is critical for directed cell migration. ?2ARs induce activation of RhoA, which is dependent on ?Arrestin2 but not Gs. ?Arrestin2 forms a complex with p115RhoGEF, a guanine nucleotide exchange factor for RhoA that is well known to be activated by G12/13-coupled receptors. Our results show that ?Arrestin2 forms a complex with p115RhoGEF in the cytosol in resting cells. Upon ?2AR activation, both ?Arrestin2 and p115RhoGEF translocate to the plasma membrane, with concomitant activation of RhoA and formation of focal adhesions and stress fibers. Activation of RhoA and focal adhesion remodeling may explain, at least in part, the role of ?2ARs in cell migration. These results suggest that ?Arrestin2 may serve as a convergence point for non-G12/13 and non-Gq protein-coupled receptors to activate RhoA. PMID:22500016

Ma, Xiaojie; Zhao, Yu; Daaka, Yehia; Nie, Zhongzhen

2012-01-01

321

Investigating the effects of bone cement, cyanoacrylate glue and marine mussel adhesive protein from Mytilus edulis on human osteoblasts and fibroblasts in vitro.  

PubMed

Bone cement is a widely used standard fixation substance in Orthopaedic Surgery. Cyanoacrylate glue is available for wound closure to supplement suturing. The mussel adhesive protein extracted from Mytilus edulis (Cell-Tak, BD Biosciences, Heidelberg, Germany) is an experimental fixation device used for in vitro purposes of cell adhesion. The aim of this study is to introduce a cell culture model investigating the effects of commonly applied and experimental glues on human fibroblasts and osteoblasts in vitro. Cells cultured without additives served as a control group. Microscopic examination was performed to evaluate the morphologic changes. An apoptosis test (Apo-Tag, Chemicon International, Temecula, CA, U. S. A.) was applied to determine the rate of natural cell death at the end of the study. It could be demonstrated that morphological changes in bone cement are different in fibroblasts and osteoblasts. Osteoblasts seem to grow on bone cement and develop an orderly formation. Fibroblasts grow in a confluent monolayer around bone cement but do not adhere to the cement itself. This is a desirable effect since most Orthopaedic applications aim at osteointegration as opposed to fibrous tissue overgrowth. Apoptosis attributed to bone cement is comparable to the respective natural rate of apoptosis. Cyanoacrylate glue and the mussel adhesive protein lead to an almost complete apoptosis in the investigated cells. Their routine application should be avoided. The developed cell culture model seems appropriate for performing further investigations. PMID:15646292

Benthien, J P; Russlies, M; Behrens, P

2004-12-01

322

Controlled spatial and conformational display of immobilised bone morphogenetic protein-2 and osteopontin signalling motifs regulates osteoblast adhesion and differentiation in vitro  

PubMed Central

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 to self assemble on a gold surface. Results A protein was engineered to contain a C-terminal cysteine that would allow chemisorption to gold, followed by 12 amino acids that form a water soluble coil that could switch to a hydrophobic helix in the presence of alkane thiols. Bioactive motifs from either bone morphogenetic protein-2 or osteopontin were added to this scaffold protein and when assembled on a gold surface assessed for their ability to influence cell function. Data demonstrate that osteoblast adhesion and short-term responsiveness to bone morphogenetic protein-2 is dependent on the surface density of a cell adhesive motif derived from osteopontin. Furthermore an immobilised cell interaction motif from bone morphogenetic protein supported bone formation in vitro over 28 days (in the complete absence of other osteogenic supplements). In addition, two-dimensional patterning of this ligand using a soft lithography approach resulted in the spatial control of osteogenesis. Conclusion These data describe an approach that allows the influence of immobilised protein ligands on cell behaviour to be dissected at the molecular level. This approach presents a durable surface that allows both short (hours or days) and long term (weeks) effects on cell activity to be assessed. This widely applicable approach can provide mechanistic insight into the contribution of immobilised ligands in the control of cell activity. PMID:20459712

2010-01-01

323

All mammalian Hedgehog proteins interact with cell adhesion molecule, down-regulated by oncogenes (CDO) and brother of CDO (BOC) in a conserved manner.  

PubMed

Hedgehog (Hh) signaling proteins stimulate cell proliferation, differentiation, and tissue patterning at multiple points in animal development. A single Hh homolog is present in Drosophila, but three Hh homologs, Sonic Hh, Indian Hh, and Desert Hh, are present in mammals. Distribution, movement, and reception of Hh signals are tightly regulated, and abnormal Hh signaling is associated with developmental defects and cancer. In addition to the integral membrane proteins Patched and Smoothened, members of the Drosophila Ihog family of adhesion-like molecules have recently been shown to bind Hh proteins with micromolar affinity and positively regulate Hh signaling. Cell adhesion molecule-related, down-regulated by oncogenes (CDO) and Brother of CDO (BOC) are the closest mammalian relatives of Drosophila Ihog, and CDO binds Sonic Hh with micromolar affinity and positively regulates Hh signaling. Despite these similarities, structural and biochemical studies have shown that Ihog and CDO utilize nonorthologous domains and completely different binding modes to interact with cognate Hh proteins. We report here biochemical and x-ray structural studies of Sonic, Indian, and Desert Hh proteins both alone and complexed with active domains of CDO and BOC. These results show that all mammalian Hh proteins bind CDO and BOC in the same manner. We also show that interactions between Hh proteins and CDO are weakened at low pH. Formation of Hh-mediated Hh oligomers is thought to be an important feature of normal Hh signaling, but no conserved self-interaction between Hh proteins is apparent from inspection of 14 independent Hh-containing crystal lattices. PMID:20519495

Kavran, Jennifer M; Ward, Matthew D; Oladosu, Oyindamola O; Mulepati, Sabin; Leahy, Daniel J

2010-08-01

324

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

325

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

326

A functionalized poly(ethylene glycol)-based bioassay surface chemistry that facilitates bio-immobilization and inhibits non-specific protein, bacterial, and mammalian cell adhesion  

PubMed Central

This paper describes a new bioassay surface chemistry that effectively inhibits non-specific biomolecular and cell binding interactions, while providing a capacity for specific immobilization of desired biomolecules. Poly(ethylene glycol) (PEG) as the primary component in nonfouling film chemistry is well-established, but the multicomponent formulation described here is unique in that it (1) is applied in a single, reproducible, solution-based coating step; (2) can be applied to diverse substrate materials without the use of special primers; and (3) is readily functionalized to provide specific attachment chemistries. Surface analysis data are presented, detailing surface roughness, polymer film thickness, and film chemistry. Protein non-specific binding assays demonstrate significant inhibition of serum, fibrinogen, and lysozyme adsorption to coated glass, indium tin oxide, and tissue culture polystyrene dishes. Inhibition of S. aureus and K. pneumoniae microbial adhesion in a microfluidic flow cell, and inhibition of fibroblast cell adhesion from serum-based cell culture is shown. Effective functionalization of the coating is demonstrated by directing fibroblast adhesion to polymer surfaces activated with an RGD peptide. Batch-to-batch reproducibility data are included. The in situ cross-linked PEG-based coating chemistry is unique in its formulation, and its surface properties are attractive for a broad range of in vitro bioassay applications. PMID:18815622

Harbers, Gregory M.; Emoto, Kazunori; Greef, Charles; Metzger, Steven W.; Woodward, Heather N.; Mascali, James J.; Grainger, David W.; Lochhead, Michael J.

2008-01-01

327

Differential adhesion, activity, and carbohydrate: Protein ratios of Pseudomonas atlantica monocultures attaching to stainless steel in a linear shear gradient  

Microsoft Academic Search

Biofilm formation on metallic surfaces in marine and freshwater environments often precedes corrosion and other biofouling conditions. Attachment is mediated by such environmental factors as the presence of surface conditioning films, fluid dynamics, bulk-phase nutrient levels, and surface chemistry. In this study, we utilized a Fowler Cell Adhesion Measurement Module to demonstrate that the changes in cellular concentration and composition

M. W. Mittelman; D. E. Nivens; C. Low; D. C. White

1990-01-01

328

Role of Streptococcus gordonii Amylase-Binding Protein A in Adhesion to Hydroxyapatite, Starch Metabolism, and Biofilm Formation  

Microsoft Academic Search

Interactions between bacteria and salivary components are thought to be important in the establishment and ecology of the oral microflora. -Amylase, the predominant salivary enzyme in humans, binds to Streptococcus gordonii, a primary colonizer of the tooth. Previous studies have implicated this interaction in adhesion of the bacteria to salivary pellicles, catabolism of dietary starches, and biofilm formation. Amylase binding

JEFFREY D. ROGERS; ROBERT J. PALMER; PAUL E. KOLENBRANDER; FRANK A. SCANNAPIECO

2001-01-01

329

Human monocyte colony-stimulating factor stimulates the gene expression of monocyte chemotactic protein-1 and increases the adhesion of monocytes to endothelial monolayers.  

PubMed Central

The stimulation of the human umbilical vein endothelial cell (HUVEC) with recombinant human monocyte-derived colony-stimulating factor (MCSF) increased the gene expression of monocyte chemotactic protein (MCP-1). Northern blot analysis indicated that 50 U/ml of MCSF is the optimal concentration for this effect. The elevation of MCP-1 mRNA started as early as 1 h after stimulation and was maintained for at least 8 h. An increased MCP-1 level in MCSF-treated HUVEC was also demonstrated at the protein level by immunocytochemical staining using a polyclonal MCP-1-specific antibody. HUVEC activated by 50 U/ml of MCSF for 5 h showed a stronger immunofluorescence staining than control cells. Micropipette separation of THP-1 monocytes from HUVEC showed that the activation of both THP-1 and endothelium by MCSF led to an increase in the separation force by more than three times (36.2 +/- 6.7 x 10(-4) vs. 9.6 +/- 3.6 x 10(-4) dyn). An increased adhesiveness was also observed after MCSF activation of peripheral blood monocytes and HUVEC (16.7 +/- 2.7 x 10(-4) vs. 5.2 +/- 0.9 x 10(-4) dyn). The increased adhesive force in both systems was blocked by the use of anti-MCP-1 (5.5 +/- 0.8 x 10(-4) and 6.8 +/- 1.1 x 10(-4) dyn). Similar results were obtained in experiments in which only HUVEC, but not monocytes, were activated by MCSF. This increased adhesion of untreated monocytes to MCSF-activated HUVEC was also blocked by the addition of anti-MCP-1. In contrast, experiments in which only THP-1 or peripheral blood monocytes, but not HUVEC, were treated with MCSF did not show a significant increase of adhesion between these cells. These results indicate that MCSF augments monocyte-endothelium interaction primarily by its action on the endothelial cell and that this function is probably mediated through an increased expression of MCP-1. The MCSF/MCP-1-dependent adhesive mechanism might be operative in the arterial wall in vivo to lead to the trapping of the infiltrated monocyte-macrophage in the subendothelial space during atherogenesis. Images PMID:8408626

Shyy, Y J; Wickham, L L; Hagan, J P; Hsieh, H J; Hu, Y L; Telian, S H; Valente, A J; Sung, K L; Chien, S

1993-01-01

330

Immunolocalization of keratin-associated beta-proteins (beta-keratins) in pad lamellae of geckos suggest that glycine-cysteine-rich proteins contribute to their flexibility and adhesiveness.  

PubMed

The epidermis of digital pads in geckos comprises superficial microornamentation from the oberhautchen layer that form long setae allowing these lizards to climb vertical surfaces. The beta-layer is reduced in pad lamellae but persists up to the apical free margin. Setae are made of different proteins including keratin-associated beta-proteins, formerly indicated as beta-keratins. In order to identify specific setal proteins the present ultrastructural study on geckos pad lamellae analyzes the immunolocalization of three beta-proteins previously found in the epidermis and adhesive setae of the green anolis. A protein rich in glycine but poor in cysteine (HgG5-like) is absent or masked in gecko pad lamellae. Another protein rich in glycine and cysteine (HgGC3-like) is weakly present in setae, oberhautchen and beta-layer. A glycine and cysteine medium rich beta-protein (HgGC10-like) is present in the lower part of the beta-layer but is absent in the oberhautchen, setae, and mesos layer. The latter two proteins may form intermolecular bonds that contribute to the flexibility of the corneous material sustaining the setae. The pliable alpha-layer present beneath the thin beta-layer and in the hinge region of the pad lamellae also contains HgGC10-like proteins. Based on the possibility that some HgGC3-like or other cys-rich beta-proteins are charged in the setae it is suggested that their charges influence the mechanism of adhesion increasing the induction of dipoles on the substrate and enhancing attractive van der Waals forces. PMID:23423812

Alibardi, Lorenzo

2013-03-01

331

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; S?balle, Kjeld; Schwarz, Edward M

2014-01-01

332

Osteoblast adhesion on biomaterials  

Microsoft Academic Search

The development of tissue engineering in the field of orthopaedic surgery is now booming. Two fields of research in particular are emerging: the association of osteo-inductive factors with implantable materials; and the association of osteogenic stem cells with these materials (hybrid materials). In both cases, an understanding of the phenomena of cell adhesion and, in particular, understanding of the proteins

K. Anselme

2000-01-01

333

The Src Homology 3 Domain Is Required for Junctional Adhesion Molecule Binding to the Third PDZ Domain of the Scaffolding Protein ZO-1*  

PubMed Central

Tight junctions are cell-cell contacts that regulate the paracellular flux of solutes and prevent pathogen entry across cell layers. The assembly and permeability of this barrier are dependent on the zonula occludens (ZO) membrane-associated guanylate kinase (MAGUK) proteins ZO-1, -2, and -3. MAGUK proteins are characterized by a core motif of protein-binding domains that include a PDZ domain, a Src homology 3 (SH3) domain, and a region of homology to guanylate kinase (GUK); the structure of this core motif has never been determined for any MAGUK. To better understand how ZO proteins organize the assembly of protein complexes we have crystallized the entire PDZ3-SH3-GUK core motif of ZO-1. We have also crystallized this core motif in complex with the cytoplasmic tail of the ZO-1 PDZ3 ligand, junctional adhesion molecule A (JAM-A) to determine how the activity of different domains is coordinated. Our study shows a new feature for PDZ class II ligand binding that implicates the two highly conserved Phe?2 and Ser?3 residues of JAM. Our x-ray structures and NMR experiments also show for the first time a role for adjacent domains in the binding of ligands to PDZ domains in the MAGUK proteins family. PMID:22030391

Nomme, Julian; Fanning, Alan S.; Caffrey, Michael; Lye, Ming F.; Anderson, James M.; Lavie, Arnon

2011-01-01

334

The Src Homology 3 Domain Is Required for Junctional Adhesion Molecule Binding to the Third PDZ Domain of the Scaffolding Protein ZO-1  

SciTech Connect

Tight junctions are cell-cell contacts that regulate the paracellular flux of solutes and prevent pathogen entry across cell layers. The assembly and permeability of this barrier are dependent on the zonula occludens (ZO) membrane-associated guanylate kinase (MAGUK) proteins ZO-1, -2, and -3. MAGUK proteins are characterized by a core motif of protein-binding domains that include a PDZ domain, a Src homology 3 (SH3) domain, and a region of homology to guanylate kinase (GUK); the structure of this core motif has never been determined for any MAGUK. To better understand how ZO proteins organize the assembly of protein complexes we have crystallized the entire PDZ3-SH3-GUK core motif of ZO-1. We have also crystallized this core motif in complex with the cytoplasmic tail of the ZO-1 PDZ3 ligand, junctional adhesion molecule A (JAM-A) to determine how the activity of different domains is coordinated. Our study shows a new feature for PDZ class II ligand binding that implicates the two highly conserved Phe{sup -2} and Ser{sup -3} residues of JAM. Our x-ray structures and NMR experiments also show for the first time a role for adjacent domains in the binding of ligands to PDZ domains in the MAGUK proteins family.

Nomme, Julian; Fanning, Alan S.; Caffrey, Michael; Lye, Ming F.; Anderson, James M.; Lavie, Arnon (NIH); (UNC); (UIC)

2012-01-20

335

The inner lives of focal adhesions  

Microsoft Academic Search

In focal adhesions of eukaryotic cells, transmembrane receptors of the integrin family and a large set of adaptor proteins form the physical link between the extracellular substrate and the actin cytoskeleton. During cell migration, nascent focal adhesions within filopodia and lamellipodia make the initial exploratory contacts with the cellular environment, whereas maturing focal adhesions pull the cell forward against the

Bernhard Wehrle-Haller; Beat A Imhof

2002-01-01

336

The Murine P84 Neural Adhesion Molecule Is SHPS-1, a Member of the Phosphatase-Binding Protein Family  

Microsoft Academic Search

P84 is a neuronal membrane glycoprotein that promotes the attachment and neurite outgrowth of cultured murine cerebellar cells. The heterophilic adhesive properties of P84 and its local- ization at sites of synaptogenesis suggest that it may be in- volved in regulation of synapse formation or maintenance. P84 is expressed in subsets of neurons throughout the CNS. By cloning the cDNA

S. Comu; W. Weng; S. Olinsky; P. Ishwad; Z. Mi; J. Hempel; S. Watkins; C. F. Lagenaur; V. Narayanan

1997-01-01

337

The ancillary protein 1 of Streptococcus pyogenes FCT-1 pili mediates cell adhesion and biofilm formation through heterophilic as well as homophilic interactions  

PubMed Central

Summary Gram-positive pili are known to play a role in bacterial adhesion to epithelial cells and in the formation of biofilm microbial communities. In the present study we undertook the functional characterization of the pilus ancillary protein 1 (AP1_M6) from Streptococcus pyogenes isolates expressing the FCT-1 pilus variant, known to be strong biofilm formers. Cell binding and biofilm formation assays using S. pyogenes in-frame deletion mutants, Lactococcus expressing heterologous FCT-1 pili and purified recombinant AP1_M6, indicated that this pilin is a strong cell adhesin that is also involved in bacterial biofilm formation. Moreover, we show that AP1_M6 establishes homophilic interactions that mediate inter-bacterial contact, possibly promoting bacterial colonization of target epithelial cells in the form of three-dimensional microcolonies. Finally, AP1_M6 knockout mutants were less virulent in mice, indicating that this protein is also implicated in GAS systemic infection. PMID:22320452

Becherelli, Marco; Manetti, Andrea G O; Buccato, Scilla; Viciani, Elisa; Ciucchi, Laura; Mollica, Giulia; Grandi, Guido; Margarit, Imma

2012-01-01

338

Photoperiod-Dependent Effects of 4-tert-Octylphenol on Adherens and Gap Junction Proteins in Bank Vole Seminiferous Tubules  

PubMed Central

In the present study we evaluated in vivo and in vitro effects of 4-tert-octylphenol (OP) on the expression and distribution of adherens and gap junction proteins, N-cadherin, ?-catenin, and connexin 43 (Cx43), in testes of seasonally breeding rodents, bank voles. We found that in bank vole testes expression and distribution of N-cadherin, ?-catenin, and Cx43 were photoperiod dependent. Long-term treatment with OP (200?mg/kg b.w.) resulted in the reduction of junction proteins expressions (P < 0.05, P < 0.01) and their delocalization in the testes of males kept in long photoperiod, whereas in short-day animals slight increase of Cx43 (P < 0.05), N-cadherin, and ?-catenin (statistically nonsignificant) levels was observed. Effects of OP appeared to be independent of FSH and were maintained during in vitro organ culture, indicating that OP acts directly on adherens and gap junction proteins in the testes. An experiment performed using an antiestrogen ICI 182,780 demonstrated that the biological effects of OP on ?-catenin and Cx43 involve an estrogen receptor-mediated response. Taken together, in bank vole organization of adherens and gap junctions and their susceptibility to OP are related to the length of photoperiod. Alterations in cadherin/catenin and Cx43-based junction may partially result from activation of estrogen receptor ? and/or ? signaling pathway. PMID:23737770

Kuras, Paulina; Lydka-Zarzycka, Marta; Bilinska, Barbara

2013-01-01

339

Intrauterine Adhesions  

MedlinePLUS

... becomes pregnant, the embryo implants in the endometrium. Injury to and/or infection of the endometrium may ... The most common cause of intrauterine adhesions is injury following a surgical procedure involving the cavity of ...

340

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

PubMed

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

2013-03-01

341

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

342

Participation of heparin binding proteins from the surface of Leishmania (Viannia) braziliensis promastigotes in the adhesion of parasites to Lutzomyia longipalpis cells (Lulo) in vitro  

PubMed Central

Background Leishmania (V.) braziliensis is a causative agent of cutaneous leishmaniasis in Brazil. During the parasite life cycle, the promastigotes adhere to the gut of sandflies, to avoid being eliminated with the dejection. The Lulo cell line, derived from Lutzomyia longipalpis (Diptera: Psychodidae), is a suitable in vitro study model to understand the features of parasite adhesion. Here, we analyze the role of glycosaminoglycans (GAGs) from Lulo cells and proteins from the parasites in this event. Methods Flagellar (Ff) and membrane (Mf) fractions from promastigotes were obtained by differential centrifugation and the purity of fractions confirmed by western blot assays, using specific antibodies for cellular compartments. Heparin-binding proteins (HBP) were isolated from both fractions using a HiTrap-Heparin column. In addition, binding of promastigotes to Lulo cells or to a heparin-coated surface was assessed by inhibition assays or surface plasmon resonance (SPR) analysis. Results The success of promastigotes subcellular fractionation led to the obtainment of Ff and Mf proteins, both of which presented two main protein bands (65.0 and 55.0kDa) with affinity to heparin. The contribution of HBPs in the adherence of promastigotes to Lulo cells was assessed through competition assays, using HS or the purified HBPs fractions. All tested samples presented a measurable inhibition rate when compared to control adhesion rate (17?±?2.0% of culture cells with adhered parasites): 30% (for HS 20?g/ml) and 16% (for HS 10?g/ml); HBP Mf (35.2% for 10?g/ml and 25.4% for 20?g/ml) and HBP Ff (10.0% for 10?g/ml and 31.4% for 20?g/ml). Additionally, to verify the presence of sulfated GAGs in Lulo cells surface and intracellular compartment, metabolic labeling with radioactive sulfate was performed, indicating the presence of an HS and chondroitin sulfate in both cell sections. The SPR analysis performed further confirmed the presence of GAGs ligands on L. (V.) braziliensis promastigote surfaces. Conclusions The data presented here point to evidences that HBPs present on the surface of L. (V.) braziliensis promastigotes participate in adhesion of these parasites to Lulo cells through HS participation. PMID:22805335

2012-01-01

343

Molecular detection of aggregation substance, enterococcal surface protein, and cytolysin genes and in vitro adhesion to urinary catheters of Enterococcus faecalis and E. faecium of clinical origin.  

PubMed

It has been hypothesized that nosocomial enterococci might have virulence factors that enhance their ability to colonise hospitalised patients. The objectives of this study were to investigate the prevalence of genes encoding 3 virulence factors: aggregation substance (asa1), enterococcal surface protein (esp), and 5 genes within the cytolysin operon (cylA, cylB, cylM, cylL(L), cylL(S)) and cytolysin production in 115 enterococcal clinical isolates (21 Enterococcus faecium and 94 E. faecalis). Adhesion to siliconized latex urinary catheters in relation to presence of esp was analysed in a subset of isolates. The isolates were previously characterised by pulsed-field gel electrophoresis (PFGE). esp was the only virulence gene found in E. faecium. It was found in 71% of the 21 E. faecium isolates. asa1, esp, and the cyl operon were found in 79%, 73% and 13% respectively, of the 94 E. faecalis isolates. There was a complete agreement between presence of the cyl operon and phenotypic cytolysin production. Isolates belonging to a cluster of genetically related isolates carried esp and asa1 more often when compared to unique isolates. No difference was found with respect to cyl genes. E. faecalis isolates adhered with higher bacterial densities than E. faecium. E. faecalis isolates within the same PFGE cluster adhered with similar bacterial densities, but there was no association between adhesion and the presence of esp when isolates within the same cluster were compared. In conclusion, E. faecalis isolates with high-level gentamicin resistance (HLGR) belonging to clusters of genetically related isolates widely distributed in Swedish hospitals, were likely to carry both esp and asa1. Adhesion was not affected by esp. PMID:19042153

Hällgren, Anita; Claesson, Carina; Saeedi, Baharak; Monstein, Hans-Jürg; Hanberger, Håkan; Nilsson, Lennart E

2009-06-01

344

Artificial biomimicking matrix modifications of nanofibrous scaffolds by hE-cadherin-Fc fusion protein to promote human mesenchymal stem cells adhesion and proliferation.  

PubMed

Extracellular matrix (ECM) plays a fundamental role in regulating cell attachment, proliferation, migration and differentiation. Both synthetic and biologically derived materials have been explored as an ECM in regenerative medicine and tissue engineering. To biomimick the extracellular matrix, we combined the advantages of the biological properties of nanofibrous scaffolds and the fusion protein to apply for the culture of human mesenchymal stem cells in vitro. In this study, we fabricated well random-oriented/aligned nanofibrous scaffolds with PCL, modified with hE-cadherin-Fc fusion protein and studied the synergistic effect of the scaffolds. The random-oriented/aligned architecture was observed in the nanofibrous scaffolds by SEM. XPS and WCA measurements evidenced that hE-cadherin-Fc was successfully modified on the PCL nanofibrous scaffolds and hydrophilicity of the scaffolds was well improved after fusion protein coating. The hE-cadherin-Fc modified markedly promoted the adhesion and proliferation of hMSCs and guided hMSCs to a spindlier morphology compared with unmodified nanofibrous scaffolds. Furthermore, hMSCs on the hE-cadherin-Fc-coated nanofibrous scaffolds also had differentiation potential. These results suggested that the combination of PCL nanofibrous scaffolds and hE-cadherin-Fc fusion protein may be a promising artificial ECM for the behavior of hMSCs in vitro. PMID:24738344

Xu, Jianbin; Li, Suhua; Hu, Feifei; Zhu, Chuanshun; Zhang, Yan; Zhao, Wei; Akaike, Toshihiro; Yang, Jun

2014-06-01

345

Opa Proteins of Pathogenic Neisseriae Initiate Src Kinase-Dependent or Lipid Raft-Mediated Uptake via Distinct Human Carcinoembryonic Antigen-Related Cell Adhesion Molecule Isoforms? †  

PubMed Central

Several pathogenic bacteria exploit human carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) for adhesion to and invasion into their host cells. CEACAM isoforms have characteristic expression patterns on epithelial, endothelial, or hematopoietic cells, providing bacteria with distinct sets of receptors on particular tissues. For example, while CEACAM1 and CEACAM6 have a wide tissue distribution, CEACAM3, CEACAM4, and CEACAM8 are uniquely expressed on primary human granulocytes, whereas CEA and CEACAM7 are limited to epithelia. By reconstitution of a CEACAM-deficient cell line with individual CEACAMs, we have analyzed the requirements for CEACAM-mediated internalization of Neisseria gonorrhoeae. Our results point to two mechanistically different uptake pathways triggered by either epithelial CEACAMs (CEACAM1, CEA, and CEACAM6) or the granulocyte-specific CEACAM3. In particular, CEACAM3-mediated uptake critically depends on Src family protein tyrosine kinase (PTK) activity, and CEACAM3 associates with the SH2 domains of several Src PTKs. In contrast, epithelial CEACAMs require the integrity of cholesterol-rich membrane microdomains and are affected by cholesterol depletion, whereas CEACAM3-mediated uptake by transfected cells or the opsonin-independent phagocytosis by human granulocytes is not altered in the presence of cholesterol chelators. These results allow the subdivision of all human CEACAMs known to be utilized as pathogen receptors into functional groups and point to important consequences for bacterial engagement of distinct CEACAM isoforms. PMID:17517873

Schmitter, Tim; Pils, Stefan; Weibel, Stephanie; Agerer, Franziska; Peterson, Lisa; Buntru, Alexander; Kopp, Kathrin; Hauck, Christof R.

2007-01-01

346

Adhesive dynamics.  

PubMed

Adhesive dynamics (AD) is a method for simulating the dynamic response of biological systems in response to force. Biological bonds are mechanical entities that exert force under strain, and applying forces to biological bonds modulates their rate of dissociation. Since small numbers of events usually control biological interactions, we developed a simple method for sampling probability distributions for the formation or failure of individual bonds. This method allows a simple coupling between force and strain and kinetics, while capturing the stochastic response of biological systems. Biological bonds are dynamically reconfigured in response to applied mechanical stresses, and a detailed spatio-temporal map of molecules and the forces they exert emerges from AD. The shape or motion of materials bearing the molecules is easily calculated from a mechanical energy balance provided the rheology of the material is known. AD was originally used to simulate the dynamics of adhesion of leukocytes under flow, but new advances have allowed the method to be extended to many other applications, including but not limited to the binding of viruses to surface, the clustering of adhesion molecules driven by stiff substrates, and the effect of cell-cell interaction on cell capture and rolling dynamics. The technique has also been applied to applications outside of biology. A particular exciting recent development is the combination of signaling with AD (so-called integrated signaling adhesive dynamics, or ISAD), which allows facile integration of signaling networks with mechanical models of cell adhesion and motility. Potential opportunities in applying AD are summarized. PMID:24384944

Hammer, Daniel A

2014-02-01

347

Hyaluronan-mediated cellular adhesion  

NASA Astrophysics Data System (ADS)

Many cells surround themselves with a cushioning halo of polysaccharides that is further strengthened and organized by proteins. In fibroblasts and chrondrocytes, the primary component of this pericellular matrix is hyaluronan, a large linear polyanion. Hyaluronan production is linked to a variety of disease, developmental, and physiological processes. Cells manipulate the concentration of hyaluronan and hyaluronan receptors for numerous activities including modulation of cell adhesion, cell motility, and differentiation. Recent investigations by identify hyaluronan's role in mediating early-stage cell adhesion. An open question is how the cell removes the 0.5-10 micron thick pericellular matrix to allow for further mature adhesion events requiring nanometer scale separations. In this investigation, holographic optical tweezers are used to study the adhesion and viscoelastic properties of chondrocytes' pericellular matrix. Ultimately, we aim to shed further light on the spatial and temporal details of the dramatic transition from micron to nanometer gaps between the cell and its adhesive substrate.

Curtis, Jennifer

2005-03-01

348

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

349

Fibrinogen Is a Ligand for the Staphylococcus aureus Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMM) Bone Sialoprotein-binding Protein (Bbp)  

PubMed Central

Microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) are bacterial surface proteins mediating adherence of the microbes to components of the extracellular matrix of the host. On Staphylococci, the MSCRAMMs often have multiple ligands. Consequently, we hypothesized that the Staphylococcus aureus MSCRAMM bone sialoprotein-binding protein (Bbp) might recognize host molecules other than the identified bone protein. A ligand screen revealed that Bbp binds human fibrinogen (Fg) but not Fg from other mammals. We have characterized the interaction between Bbp and Fg. The binding site for Bbp was mapped to residues 561–575 in the Fg A? chain using recombinant Fg chains and truncation mutants in Far Western blots and solid-phase binding assays. Surface plasmon resonance was used to determine the affinity of Bbp for Fg. The interaction of Bbp with Fg peptides corresponding to the mapped residues was further characterized using isothermal titration calorimetry. In addition, Bbp expressed on the surface of bacteria mediated adherence to immobilized Fg A?. Also, Bbp interferes with thrombin-induced Fg coagulation. Together these data demonstrate that human Fg is a ligand for Bbp and that Bbp can manipulate the biology of the Fg ligand in the host. PMID:21642438

Vazquez, Vanessa; Liang, Xiaowen; Horndahl, Jenny K.; Ganesh, Vannakambadi K.; Smeds, Emanuel; Foster, Timothy J.; Hook, Magnus

2011-01-01

350

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

351

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

PubMed

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 Thr(268); previously only flagellin proteins were known to be O-glycosylated in C. jejuni. Substitution of MOMP Thr(268) 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-Thr(268); modelling suggested that O-glycosylation has a notable effect on the conformation of MOMP and this modulates BgAg-binding capacity. Glycosylation of MOMP at Thr(268) 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

352

Natural Underwater Adhesives.  

PubMed

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

2011-06-01

353

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

354

Focal adhesion size uniquely predicts cell migration  

PubMed Central

Focal adhesions are large protein complexes organized at the basal surface of cells, which physically connect the extracellular matrix to the cytoskeleton and have long been speculated to mediate cell migration. However, whether clustering of these molecular components into focal adhesions is actually required for these proteins to regulate cell motility is unclear. Here we use quantitative microscopy to characterize descriptors of focal adhesion and cell motility for mouse embryonic fibroblasts and human fibrosarcoma cells, across a wide range of matrix compliance and following genetic manipulations of focal adhesion proteins (vinculin, talin, zyxin, FAK, and paxilin). This analysis reveals a tight, biphasic gaussian relationship between mean size of focal adhesions (not their number, surface density, or shape) and cell speed. The predictive power of this relationship is comprehensively validated by disrupting nonfocal adhesion proteins (?-actinin, F-actin, and myosin II) and subcellular organelles (mitochondria, nuclear DNA, etc.) not known to affect either focal adhesions or cell migration. This study suggests that the mean size of focal adhesions robustly and precisely predicts cell speed independently of focal adhesion surface density and molecular composition.—Kim, D.-H., Wirtz, D. Focal adhesion size uniquely predicts cell migration. PMID:23254340

Kim, Dong-Hwee; Wirtz, Denis

2013-01-01

355

Engineering Cell Adhesion  

Microsoft Academic Search

\\u000a Cells exist within a complex and ever-changing environment, which includes soluble molecules such as growth factors, an extracellular\\u000a matrix that includes adhesive proteins and carbohydrates, and other neighboring cells. They actively sense and respond to\\u000a changes in this environment, existing in a state of physiological equilibrium with it. Thus, it has been said, “. . . the\\u000a unit of function

Kiran Bhadriraju; Wendy F. Liu; Darren S. Gray; Christopher S. Chen

356

Adhesion Mechanisms of Staphylococci  

Microsoft Academic Search

\\u000a Staphylococcal adherence to an either biotic or abiotic surface is the critical first event in the establishment of an infection\\u000a with these serious pathogens. Especially Staphylococcus aureus harbours a variety of proteinaceous and non-proteinaceous adhesins that mediate attachment to a multitude of host factors,\\u000a such as extracellular matrix and plasma proteins and human host cells, or intercellular adhesion, which is

Christine Heilmann

357

Arginine-glycine-aspartic acid- and fibrinogen gamma-chain carboxyterminal peptides inhibit platelet adherence to arterial subendothelium at high wall shear rates. An effect dissociable from interference with adhesive protein binding.  

PubMed Central

Arg-Gly-Asp (RGD)- and fibrinogen gamma-chain carboxyterminal (GQQHHLGGAKQAGDV) peptides inhibit fibrinogen, fibronectin (Fn), vitronectin, and von Willebrand factor (vWF) binding to the platelet glycoprotein IIb-IIIa complex (GP IIb-IIIa). GP IIb-IIIa, vWF, and Fn are essential for normal platelet adherence to subendothelium. We added peptides to normal citrated whole blood before perfusion over human umbilical artery subendothelium and evaluated platelet adherence morphometrically at high (2,600 s-1) and low (800 s-1) wall shear rates. We also examined the effects of the peptides on platelet adhesion to collagen in a static system. At the high wall shear rate, RGDS and GQQHHLGGAKQAGDV caused dose-dependent reduction in the surface coverage with spread and adherent platelets. Amino acid transposition and conservative substitutions of RGD peptides and the AGDV peptide significantly inhibited platelet adherence at 2,600 s-1. By contrast, the modified RGD peptides and AGDV do not affect adhesive protein binding to platelets. None of the native or modified RGD- or fibrinogen gamma-chain peptides significantly inhibited either platelet adherence to subendothelium at 800 s-1 or platelet adhesion to collagen. Our findings demonstrate that peptides that interfere with adhesive protein binding to GP IIb-IIIa inhibit platelet adherence to vascular subendothelium with flowing blood only at high wall shear rates. Platelet adherence to subendothelium at high wall shear rates appears to be mediated by different recognition specificities from those required for fluid-phase adhesive protein binding or static platelet adhesion. PMID:2243140

Lawrence, J B; Kramer, W S; McKeown, L P; Williams, S B; Gralnick, H R

1990-01-01

358

Genes involved in cell adhesion, cell motility and mitogenic signaling are altered due to HPV 16 E5 protein expression  

Microsoft Academic Search

We investigated the effects of the human papillomavirus type 16 E5 oncogene on cellular gene expression in human epithelial cells using cDNA microarray. In a genome-wide microarray assay, the expression of 179 genes was found to be significantly altered due to E5 expression. The expression of lamin A\\/C was downregulated at protein level. The expression of protein kinase C-? and

N Kivi; D Greco; P Auvinen; E Auvinen

2008-01-01

359

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

PubMed

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

360

Grb2 Promotes Integrin-Induced Focal Adhesion Kinase (FAK) Autophosphorylation and Directs the Phosphorylation of Protein Tyrosine Phosphatase ? by the Src-FAK Kinase Complex  

PubMed Central

The integrin-activated Src-focal adhesion kinase (FAK) kinase complex phosphorylates PTP? at Tyr789, initiating PTP?-mediated signaling that promotes cell migration. Recruitment of the BCAR3-Cas complex by PTP?-phospho-Tyr789 at focal adhesions is one mechanism of PTP? signaling. The adaptor protein Grb2 is also recruited by PTP?-phospho-Tyr789, although the role of the PTP?-Grb2 complex in integrin signaling is unknown. We show that silencing Grb2 expression in fibroblasts abolishes PTP?-Tyr789 phosphorylation and that this is due to two unexpected actions of Grb2. First, Grb2 promotes integrin-induced autophosphorylation of FAK-Tyr397. This is impaired in Grb2-depleted cells and prohibits FAK activation and formation of the Src-FAK complex. Grb2-depleted cells contain less paxillin, and paxillin overexpression rescues FAK-Tyr397 phosphorylation, suggesting that the FAK-activating action of Grb2 involves paxillin. A second distinct role for Grb2 in PTP?-Tyr789 phosphorylation involves Grb2-mediated coupling of Src-FAK and PTP?. This requires two phosphosites, FAK-Tyr925 and PTP?-Tyr789, for Grb2-Src homology 2 (SH2) binding. We propose that a Grb2 dimer links FAK and PTP?, and this positions active Src-FAK in proximity with other, perhaps integrin-clustered, molecules of PTP? to enable maximal PTP?-Tyr789 phosphorylation. These findings identify Grb2 as a new FAK activator and reveal its essential role in coordinating PTP? tyrosine phosphorylation to enable downstream integrin signaling and migration. PMID:24248601

Cheng, Suzanne Y. S.; Sun, Guobin; Schlaepfer, David D.

2014-01-01