Npj. Brindle et al., THE FOCAL-ADHESION VASODILATOR-STIMULATED PHOSPHOPROTEIN (VASP) BINDSTO THE PROLINE-RICH DOMAIN IN VINCULIN, Biochemical journal, 318, 1996, pp. 753-757
In mammalian cells vasodilator-stimulated phosphoprotein (VASP) is loc
alized to focal adhesions and areas of dynamic membrane activity where
it is thought to have a role in actin-filament assembly. The proteins
responsible for recruiting VASP to these sites within the cell are no
t known. The bacterial protein ActA binds VASP via a proline-rich moti
f that is very similar to a sequence in the proline-rich region of the
focal-adhesion protein vinculin. We have examined the ability of VASP
, synthesized using an in vitro transcription/translation system, to b
ind to a series of vinculin peptides expressed as glutathione S-transf
erase fusion proteins, and have shown that it binds specifically to th
e proline-rich region in vinculin. Using immobilized peptides correspo
nding to the two proline-rich motifs within this domain, the VASP-bind
ing site was localized to proline-rich motif-1 (residues 839-850). Bin
ding to this motif was not affected by the phosphorylation state of VA
SP. The C-terminal region of VASP, which is known to be important in t
argeting VASP to focal adhesions, was shown to be required for binding
. These results identify vinculin as a VASP-binding protein likely to
be important in recruiting VASP to focal adhesions and the cell membra
ne.