Tuning Myoblast and Preosteoblast Cell Adhesion Site, Orientation, and Elongation through Electroactive Micropatterned Scaffolds

Basement membrane-adherent type II alveolar cells isolated from lung assemble into lumen-containing cellular spheres which retain the correct polarity and thereby approximate the earliest fetal stage of alveolar morphogenesis. The molecular basis of this process, determined in initial experiments to be attributable mainly to the large heterotrimeric glycoprotein laminin, was probed with laminin proteolytic fragments, antibodies, and synthetic peptides. The carboxy-terminal fragment E8, but not equimolar amounts of fragment P1, blocked alveolar formation. To pursue this observation, we used several anti-E8 antibodies and identified one, prepared against A chain residues 2179-2198 ("SN-peptide") from the first loop of the G domain, as inhibitory. These results were confirmed by use of SN-peptide alone and further defined by trypsin digestion of SN-peptide to the sequence SINNNR. This conserved site promoted divalent cation dependent adhesion of both type II alveolar and HT1080 cells, was inhibitable with equimolar amounts of fragment E8 but not P1, and derives from a form of laminin present in fetal alveolar basement membranes. These studies point to an important novel cell adhesion site in the laminin E8 region with a key role in lung alveolar morphogenesis.

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Identification and characterization of the T lymphocyte adhesion receptor for an alternative cell attachment domain (CS-1) in plasma fibronectin.

The Journal of Cell Biology ◽

10.1083/jcb.109.3.1321 ◽

1989 ◽

Vol 109 (3) ◽

pp. 1321-1330 ◽

Cited By ~ 481

Author(s):

E A Wayner ◽

A Garcia-Pardo ◽

M J Humphries ◽

J A McDonald ◽

W G Carter

Keyword(s):

Cell Adhesion ◽

T Lymphocytes ◽

T Lymphocyte ◽

Plasma Fibronectin ◽

Fibronectin Receptor ◽

Lymphocyte Adhesion ◽

Receptor Alpha ◽

Tryptic Fragment ◽

Carboxy Terminal ◽

Adhesion Site

Using mAb technology (Wayner, E. A., W. G. Carter, R. Piotrowicz, and T. J. Kunicki. 1988. J. Cell Biol. 107:1881-1891), we have identified a new fibronectin receptor that is identical to the integrin receptor alpha 4 beta 1. mAbs P3E3, P4C2, and P4G9 recognized epitopes on the alpha 4 subunit and completely inhibited the adhesion of peripheral blood and cultured T lymphocytes to a 38-kD tryptic fragment of plasma fibronectin containing the carboxy-terminal Heparin II domain and part of the type III connecting segment (IIICS). The ligand in IIICS for alpha 4 beta 1 was the CS-1 region previously defined as an adhesion site for melanoma cells. The functionally defined mAbs to alpha 4 partially inhibited T lymphocyte adhesion to intact plasma fibronectin and had no effect on their attachment to an 80-kD tryptic fragment containing the RGD (arg-gly-asp) adhesion sequence. mAbs (P1D6 and P1F8) to the previously described fibronectin receptor, alpha 5 beta 1, completely inhibited T lymphocyte adhesion to the 80-kD fragment but had no effect on their attachment to the 38-kD fragment or to CS-1. Both alpha 4 beta 1 and alpha 5 beta 1 localized to focal adhesions when fibroblasts that express these receptors were grown on fibronectin-coated surfaces. These findings demonstrated a specific interaction of both receptors with fibronectin at focal contacts. In conclusion, these findings show clearly that cultured T lymphocytes use two independent receptors during attachment to fibronectin and that (a) alpha 5 beta 1 is the receptor for the RGD containing cell adhesion domain, and (b) alpha 4 beta 1 is the receptor for a carboxy-terminal cell adhesion region containing the Heparin II and IIICS domains. Furthermore, these data also show that T lymphocytes express a clear preference for a region of molecular heterogeneity in IIICS (CS-1) generated by alternative splicing of fibronectin pre-mRNA and that alpha 4 beta 1 is the receptor for this adhesion site.

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Kallmann's Syndrome with a Novel Missense Mutation in the KALI Gene that Modifies the Major Cell Adhesion Site of the Anosmin-1 Protein

Journal of Pediatric Endocrinology and Metabolism ◽

10.1515/jpem.2005.18.6.545 ◽

2005 ◽

Vol 18 (6) ◽

Cited By ~ 6

Author(s):

L. Loidi ◽

L. Castro-Feijoo ◽

J. Barreiro ◽

C. Quinteiro ◽

P. Cabanas ◽

...

Keyword(s):

Cell Adhesion ◽

Missense Mutation ◽

Kallmann's Syndrome ◽

Kallmann’S Syndrome ◽

Adhesion Site

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Characterization of the Cell Adhesion Site ofTrypanosoma cruzi Metacyclic Stage Surface Glycoprotein gp82

Infection and Immunity ◽

10.1128/iai.68.2.478-484.2000 ◽

2000 ◽

Vol 68 (2) ◽

pp. 478-484 ◽

Cited By ~ 30

Author(s):

Patricio M. Manque ◽

Daniel Eichinger ◽

Maria A. Juliano ◽

Luiz Juliano ◽

Jorge E. Araya ◽

...

Keyword(s):

Amino Acids ◽

Cell Adhesion ◽

Recombinant Proteins ◽

Synthetic Peptides ◽

Surface Glycoprotein ◽

Target Cells ◽

Cell Binding ◽

Parasite Invasion ◽

Central Domain ◽

Adhesion Site

ABSTRACT The surface glycoprotein gp82, expressed in the insect-stage metacyclic trypomastigotes of Trypanosoma cruzi, has been implicated in mammalian cell invasion. Here we have characterized the cell adhesion site of gp82 by using recombinant proteins and synthetic peptides based on gp82. The recombinant protein Del-4/8, lacking 65 amino acids of gp82 central domain (at positions 257 to 321), was virtually devoid of cell-binding activity and lacked the ability to inhibit parasite invasion, in contrast to J18, the construct containing the full-length gp82 sequence (amino acids 1 to 516). Constructs with shorter deletions, i.e., Del-4 (deleted from 257 to 271) and Del-8 (deleted from 293 to 321), bound to target cells to a significantly lesser degree than did J18. The sites deleted in recombinant proteins Del-4 and Del-8 contained acidic amino acids critical for cell adhesion. Thus, the cell-binding capacity of protein Del-E/D, lacking the glutamic acid (259/260) and aspartic acid (303/304) pairs, was negligible, as was its capacity to inhibit parasite internalization. Of a set of synthetic peptides spanning the gp82 central domain, a 22-mer hybrid peptide, p4/8, formed by two noncontiguous sequences (at positions 257 to 273 and 302 to 306) and containing the four acidic residues, competed with the binding of J18 protein to target cells and significantly inhibited (∼60%) the penetration of parasites. This peptide, generated by the juxtaposition of sequences that are separated by a hydrophobic stretch in the linear molecule, appears to be mimicking a conformation-dependent cell-binding site of gp82. Experiments of antibody competition with a set of 20-mer overlapping peptides mapped the epitope for 3F6, a monoclonal antibody directed to gp82 that inhibits parasite invasion, to the sequence represented by peptide p3 (244 to 263), which has a partial overlap with the cell adhesion site.

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