K. Kato et al., ADDITIONAL RECOGNITION SITES IN THE C-TERMINAL HEPARIN-BINDING DOMAINOF FIBRONECTIN PROMOTE ADHESION OF PMA-TREATED U937 CELLS, Peptides, 19(1), 1998, pp. 7-13
Recently we have shown an evidence that a peptide, corresponding to re
sidues Gln(1892) to Gly(1910), from the C-terminal heparin-binding dom
ain of fibronectin promotes adhesion of phorbol-12-myristate 13-acetat
e (PMA)-treated U937 cells and binds to both integrin alpha(4) beta(1)
and glycosaminoglycans on U937 cells surface. We present additional a
dhesion-promoting sites to PMA-treated U937 cells present in the C-ter
minal heparin-binding domain of fibronectin. Three synthetic peptides
(residues Ala(1819) to Lys(1830), designated E5; Thr(1828) to Gly(1940
), E4; and Lys(1946) to Leu(1963), D1) were active to inhibit adhesion
of PMA-treated U937 cells to the 29-kDa fragment comprising the C-ter
minal heparin-binding domain of fibronectin. Scrambled versions of the
se peptides had no inhibitory activity on this adhesion. The IgG-conju
gated peptides (IgG-ES, IgG-E4, and IgG-D1) were also active and suppo
rted adhesion to an extent comparable to that of the 29-kDa fragment.
The adhesion of PMA-treated U937 cells on these three IgG-conjugated p
eptides was only inhibited by glycosaminoglycans and not by integrin a
lpha(4) beta(1). These results indicate that additional adhesion-promo
ting sequences are present in the C-terminal heparin-binding domain of
fibronectin and that the activity of these peptides depends on peptid
e sequence, mainly the result of net charges or net hydropathy indices
. (C) 1998 Elsevier Science Inc.