Additional recognition sites in the C-terminal heparin-binding domain of fibronectin promote adhesion of PMA-treated U937 cells.
Recently we have shown an evidence that a peptide, corresponding to residues Gln1892 to Gly1910, from the C-terminal heparin-binding domain of fibronectin promotes adhesion of phorbol-12-myristate 13-acetate (PMA)-treated U937 cells and binds to both integrin alpha 4 beta 1 and glycosaminoglycans on U937 cells surface. We present additional adhesion-promoting sites to PMA-treated U937 cells present in the C-terminal heparin-binding domain of fibronectin. Three synthetic peptides (residues Ala1819 to Lys1830, designated E5; Thr1828 to Gly1940, E4; and Lys1946 to Leu1963, D1) were active to inhibit adhesion of PMA-treated U937 cells to the 29-kDa fragment comprising the C-terminal heparin-binding domain of fibronectin. Scrambled versions of these peptides had no inhibitory activity on this adhesion. The IgG-conjugated peptides (IgG-E5, IgG-E4, and IgG-D1) were also active and supported adhesion to an extent comparable to that of the 29-kDa fragment. The adhesion of PMA-treated U937 cells on these three IgG-conjugated peptides was only inhibited by glycosaminoglycans and not by integrin alpha 4 beta 1. These results indicate that additional adhesion-promoting sequences are present in the C-terminal heparin-binding domain of fibronectin and that the activity of these peptides depends on peptide sequence, mainly the result of net charges or net hydropathy indices.
Kato
K
K
First Department of Internal Medicine, Yokohama City University School of Medicine, Japan.
Hashimoto
Y
Y
Kanamori
H
H
Okubo
T
T
Mohri
H
H
D000595:Amino Acid Sequence; D000906:Antibodies / Q000276:immunology; D002448:Cell Adhesion / Q000187:drug effects*; D005353:Fibronectins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D006025:Glycosaminoglycans / Q000378:metabolism; D006493:Heparin / Q000378:metabolism*; D006801:Humans; D007074:Immunoglobulin G / Q000737:chemistry / Q000378:metabolism; D039041:Integrin alpha4beta1; D016023:Integrins / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D009000:Monocytes / Q000187:drug effects / Q000502:physiology*; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding; D016201:Receptors, Lymphocyte Homing / Q000276:immunology / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000906:Antibodies; D005353:Fibronectins; D006025:Glycosaminoglycans; D007074:Immunoglobulin G; D039041:Integrin alpha4beta1; D016023:Integrins; D010446:Peptide Fragments; D016201:Receptors, Lymphocyte Homing; D006493:Heparin; D013755:Tetradecanoylphorbol Acetate