scholarly journals A synthetic peptide from the COOH-terminal heparin-binding domain of fibronectin promotes focal adhesion formation.

1993 ◽  
Vol 4 (6) ◽  
pp. 605-613 ◽  
Author(s):  
A Woods ◽  
J B McCarthy ◽  
L T Furcht ◽  
J R Couchman
Keyword(s):  
Cell Surface ◽  
Focal Adhesion ◽  
Cell Attachment ◽  
Adhesion Formation ◽  
Binding Domain ◽  
Amino Acid Sequences ◽  
Fiber Formation ◽  
Heparin Binding ◽  
Focal Adhesion Formation ◽  
Heparin Binding Domain

Cell adhesion to extracellular matrix molecules such as fibronectin involves complex transmembrane signaling processes. Attachment and spreading of primary fibroblasts can be promoted by interactions of cell surface integrins with RGD-containing fragments of fibronectin, but the further process of focal adhesion and stress fiber formation requires additional interactions. Heparin-binding fragments of fibronectin can provide this signal. The COOH-terminal heparin-binding domain of fibronectin contains five separate heparin-binding amino acid sequences. We show here that all five sequences, as synthetic peptides coupled to ovalbumin, can support cell attachment. Only three of these sequences can promote focal adhesion formation when presented as multicopy complexes, and only one of these (WQPPRARI) retains this activity as free peptide. The major activity of this peptide resides in the sequence PRARI. The biological response to this peptide and to the COOH-terminal fragment may be mediated through cell surface heparan sulfate proteoglycans because treatment of cells with heparinase II and III, or competition with heparin, reduces the response. Treatment with chondroitinase ABC or competition with chondroitin sulfate does not.

scholarly journals A synthetic peptide from the heparin-binding domain III (repeats III4-5) of fibronectin promotes stress-fibre and focal-adhesion formation in melanoma cells

2003 ◽  
Vol 371 (2) ◽  
pp. 565-571 ◽  
Author(s):  
José V. MOYANO ◽  
Alfredo MAQUEDA ◽  
Juan P. ALBAR ◽  
Angeles GARCIA-PARDO
Keyword(s):  
Cell Adhesion ◽  
Focal Adhesion ◽  
Adhesion Formation ◽  
Focal Adhesions ◽  
Melanoma Cells ◽  
Small Gtpase ◽  
Binding Domain ◽  
Heparin Binding ◽  
Chondroitin Sulphate Proteoglycans ◽  
Heparin Binding Domain

Cell adhesion to fibronectin results in formation of actin stress fibres and focal adhesions. In fibroblasts, this response requires two co-operative signals provided by interactions of the RGD sequence with α5β1 integrin and the heparin-binding domain II (Hep II) domain with syndecan-4. Within Hep II, this activity was mapped to repeat III13 and to the peptide FN-C/H-V(WQPPRARITGY, repeat III14). We previously described that the synthetic heparin-binding peptide/III5 (HBP/III5) (WTPPRAQITGYRLTVGLTRR, repeat III5) binds heparin and mediates cell adhesion via chondroitin sulphate proteoglycans. We have now studied whether HBP/III5 co-operates with α5β1 and drives a full cytoskeletal response in melanoma cells. SKMEL-178 cells attached and spread on the RGD-containing FNIII7–FNIII10 (FNIII7–10) fragment, but did not form stress fibres or focal adhesions. Co-immobilization of HBP/III5 with FNIII7–10 or adding soluble HBP/III5 to cells prespread on FNIII7–10, effectively induced these structures. Cell transfection with dominant-negative N19RhoA, a member of the small GTPase family, abolished the HBP/III5 effect. Both chondroitinase and heparitinase diminished focal adhesions, indicating that both types of proteoglycans bound HBP/III5 in melanoma cells. We have mapped the active sequence of HBP/III5 to YRLTVGLTRR, which is a novel sequence in fibronectin with focal-adhesion-promoting activity. The last two arginine (R) residues of this sequence are required for activity, since their replacement by alanine completely abrogated the HBP/III5 cytoskeletal effect. Moreover, this sequence is also active in the context of large fibronectin fragments. Our results establish that the Hep III region provides co-operative signals to α5β1 for the progression of the cytoskeletal response and that these include activation of RhoA.

scholarly journals Thrombospondin modulates focal adhesions in endothelial cells.

1989 ◽  
Vol 109 (3) ◽  
pp. 1309-1319 ◽  
Author(s):  
J E Murphy-Ullrich ◽  
M Höök
Keyword(s):  
Endothelial Cells ◽  
Focal Adhesion ◽  
Adhesion Formation ◽  
Focal Adhesions ◽  
Cell Spreading ◽  
Heparin Binding ◽  
Focal Adhesion Formation ◽  
Heparin Binding Domain ◽  
Adhesion Plaques ◽  
Number Of Cells

We examined the effects of thrombospondin (TSP) in the substrate adhesion of bovine aortic endothelial cells. The protein was tested both as a substrate for cell adhesion and as a modulator of the later stages of the cell adhesive process. TSP substrates supported the attachment of some BAE cells, but not cell spreading or the formation of focal adhesion plaques. In contrast, cells seeded on fibrinogen or fibronectin substrates were able to complete the adhesive process, as indicated by the formation of focal adhesion plaques. Incubation of cells in suspension with soluble TSP before or at the time of seeding onto fibronectin substrates resulted in an inhibition of focal adhesion formation. Furthermore, the addition of TSP to fully adherent cells in situ or prespread on fibronectin substrates caused a reduction in the number of cells, which were positive for focal adhesions, although there was no significant effect on cell spreading. In a dose-dependent manner, TSP reduced the number of cells with adhesion plaques to approximately 60% of control levels. The distribution of remaining adhesion plaques in TSP-treated cells was also altered: plaques were primarily limited to the periphery of cells and were not present in the central cell body, as in control cells treated with BSA. The observed effects were specific for TSP and were not observed with platelet factor 4, beta-thromboglobulin, or fibronectin. The TSP-mediated loss of adhesion plaques was neutralized by the addition of heparin, fucoidan, other heparin-binding proteins, and by a monoclonal antibody to the heparin binding domain of TSP, but not by antibodies to the core or carboxy-terminal regions of TSP. The interaction of the heparin-binding domain of TSP with cell-associated heparan sulfate appears to be an important mechanistic component for this activity of TSP. These data indicate that TSP may have a role in destabilizing cell adhesion through prevention of focal adhesion formation and by loss of preformed focal adhesions.

scholarly journals Activation of Rho-kinase and focal adhesion kinase regulates the organization of stress fibers and focal adhesions in the central part of fibroblasts

2017 ◽  
Author(s):  
Kazuo Katoh
Keyword(s):  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Adhesion Formation ◽  
Rho Kinase ◽  
Focal Adhesions ◽  
Fiber Formation ◽  
Stress Fibers ◽  
Focal Adhesion Formation ◽  
Specific Regulation

Specific regulation and activation of focal adhesion kinase (FAK) are thought to be important for focal adhesion formation, and activation of Rho-kinase has been suggested to play a role in determining the effects of FAK on the formation of stress fibers and focal adhesions. To clarify the role of FAK in stress fiber formation and focal adhesion organization, we examined the formation of new stress fibers and focal adhesions by activation of Rho-kinase in FAK knockout (FAK–/–) fibroblasts. FAK–/– cells were elliptical in shape, and showed reduced numbers of stress fibers and focal adhesions in the central part of the cells along with large focal adhesions in the peripheral regions. Activation of Rho-kinase in FAK–/– cells transiently increased the actin filaments in the cell center, but these did not form typical thick stress fibers. Moreover, only plaque-like structures as the origins of newly formed focal adhesions were observed in the center of the cell. Furthermore, introduction of an exogenous GFP-labeled FAK gene into FAK–/– cells resulted in increased numbers of stress fibers and focal adhesions in the center of the cells, which showed typical fibroblast morphology. These results indicated that FAK plays an important role in the formation of stress fibers and focal adhesions as well as in regulation of cell shape and morphology with the activation of Rho-kinase.

scholarly journals Platelet thrombospondin mediates attachment and spreading of human melanoma cells.

1987 ◽  
Vol 104 (1) ◽  
pp. 131-139 ◽  
Author(s):  
D D Roberts ◽  
J A Sherwood ◽  
V Ginsburg
Keyword(s):  
Monoclonal Antibodies ◽  
Cell Attachment ◽  
Melanoma Cells ◽  
Binding Domain ◽  
Heparin Binding ◽  
Amino Terminal ◽  
Sulfated Fucan ◽  
Heparin Binding Domain ◽  
Carboxyl Terminal ◽  
Inhibition Studies

Human platelet thrombospondin adsorbed on plastic promotes attachment and spreading of human G361 melanoma cells. Attachment is rapid, and spreading is maximal by 90 min with 60-90% of the attached cells spread. In contrast, thrombospondin promotes attachment but not spreading of human C32 melanoma cells, which attach and spread only on laminin substrates. The specificity of these interactions and the regions of the thrombospondin molecule involved in attachment and spreading were examined using proteolytic fragments of thrombospondin and by inhibition studies. The sulfated fucan, fucoidan, and monoclonal antibody A2.5, which is directed against the heparin-binding domain of thrombospondin, selectively inhibit spreading but only weakly inhibit attachment. Monoclonal antibodies against some other domains of thrombospondin, however, are potent inhibitors of attachment. The amino-terminal heparin-binding domain of thrombospondin does not promote attachment. Large fragments lacking the heparin-binding domain support attachment but not spreading of G361 cells. Attachment activity is lost following removal of the 18-kD carboxyl-terminal domain. These results suggest that at least two melanoma ligands are involved in cell attachment and spreading on thrombospondin. The carboxyl-terminal region and perhaps other regions of the molecule bind to receptor(s) on the melanoma surface that promote initial attachment but not cell spreading. Interaction of the heparin-binding domain with sulfated glycoconjugates on melanoma surface proteoglycans and/or sulfated glycolipids mediates spreading. Monoclonal antibodies A2.5 and C6.7 also reverse spreading of G361 cells growing on glass culture substrates, suggesting that binding to thrombospondin mediates attachment of these melanoma cells in culture.

scholarly journals Activation of Rho-kinase and focal adhesion kinase regulates the organization of stress fibers and focal adhesions in the central part of fibroblasts

2017 ◽  
Author(s):  
Kazuo Katoh
Keyword(s):  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Adhesion Formation ◽  
Rho Kinase ◽  
Focal Adhesions ◽  
Fiber Formation ◽  
Stress Fibers ◽  
Focal Adhesion Formation ◽  
Specific Regulation

Specific regulation and activation of focal adhesion kinase (FAK) are thought to be important for focal adhesion formation, and activation of Rho-kinase has been suggested to play a role in determining the effects of FAK on the formation of stress fibers and focal adhesions. To clarify the role of FAK in stress fiber formation and focal adhesion organization, we examined the formation of new stress fibers and focal adhesions by activation of Rho-kinase in FAK knockout (FAK–/–) fibroblasts. FAK–/– cells were elliptical in shape, and showed reduced numbers of stress fibers and focal adhesions in the central part of the cells along with large focal adhesions in the peripheral regions. Activation of Rho-kinase in FAK–/– cells transiently increased the actin filaments in the cell center, but these did not form typical thick stress fibers. Moreover, only plaque-like structures as the origins of newly formed focal adhesions were observed in the center of the cell. Furthermore, introduction of an exogenous GFP-labeled FAK gene into FAK–/– cells resulted in increased numbers of stress fibers and focal adhesions in the center of the cells, which showed typical fibroblast morphology. These results indicated that FAK plays an important role in the formation of stress fibers and focal adhesions as well as in regulation of cell shape and morphology with the activation of Rho-kinase.

scholarly journals Heparin-binding EGF-like growth factor stimulation of smooth muscle cell migration: dependence on interactions with cell surface heparan sulfate

1993 ◽  
Vol 122 (4) ◽  
pp. 933-940 ◽  
Author(s):  
S Higashiyama ◽  
JA Abraham ◽  
M Klagsbrun
Keyword(s):  
Smooth Muscle ◽  
Growth Factor ◽  
Cell Surface ◽  
Heparan Sulfate ◽  
Cho Cells ◽  
Egf Receptor ◽  
Binding Domain ◽  
Heparin Binding ◽  
Heparin Binding Domain ◽  
Stimulation Of

Heparin-binding EGF-like growth factor (HB-EGF), but not EGF, binds to cell surface heparan sulfate proteoglycan (HSPG). This was demonstrated in (a) the binding of 125I-HB-EGF to mutant CHO cells deficient in HS production was diminished by 70% compared to wild-type CHO cells, (b) the binding of 125I-HB-EGF to CHO cells and bovine aortic smooth muscle cells (BASMC) was diminished 80% by heparitinase or chlorate treatment, and (c) 125I-EGF did not bind to CHO cells and its binding to BASMC was not diminished at all by heparitinase and only slightly by chlorate treatment. Accordingly, the role of HB-EGF interactions with HSPG in modulating bioactivity was examined. Heparitinase or chlorate treatment of BASMC diminished the ability of HB-EGF to stimulate BASMC migration by 60-80%. A similar inhibition of migration occurred when BASMC were treated with a synthetic peptide (P21) corresponding to the sequence of the putative heparin-binding domain of HB-EGF. As a control for BASMC viability, and for specificity, it was found that heparitinase and P21 did not inhibit at all and chlorate inhibited only slightly the stimulation of BASMC migration by PDGF AB. Since heparitinase, chlorate, and P21 treatment also diminished by 70-80% the cross-linking of 125I-HB-EGF to the EGF receptor, it was concluded that the interaction of HB-EGF, via its heparin-binding domain, with cell surface HSPG was essential for its optimal binding to the EGF receptor on BASMC and hence for its optimal ability to stimulate migration.

The leucine-rich repeat protein PRELP binds fibroblast cell-surface proteoglycans and enhances focal adhesion formation

2016 ◽  
Vol 473 (9) ◽  
pp. 1153-1164 ◽  
Author(s):  
Eva Bengtsson ◽  
Karin Lindblom ◽  
Viveka Tillgren ◽  
Anders Aspberg
Keyword(s):  
Cell Surface ◽  
Focal Adhesion ◽  
Matrix Protein ◽  
Adhesion Formation ◽  
Fibroblast Cell ◽  
Extracellular Matrix Protein ◽  
Leucine Rich Repeat ◽  
Repeat Protein ◽  
Focal Adhesion Formation ◽  
Leucine Rich Repeat Protein

The extracellular matrix protein PRELP (proline/arginine-rich end leucine-rich repeat protein) binds heparin. We now show that PRELP binds syndecan cell-surface proteoglycans and enhances focal adhesion formation. This suggest a role for PRELP in modulating cell adhesion and migration.

Sign in / Sign up

Export Citation Format

Share Document