THE FOCAL ADHESION PHOSPHOPROTEIN, VASP

Vasodilator-stimulated phosphoprotein (VASP) is associated with focal adhesions and areas of dynamic membrane activity, where it is thought to have an important role in actin filament assembly and cell motility . VASP contains a central proline-rich sequence which recruits the G-a ctin binding protein profilin. Localization of VASP to the leading edg e of a migrating cell can lead to local accumulation of profilin, whic h in turn can supply actin monomers to growing filament ends. VASP bin ds to the focal adhesion proteins vinculin and zyxin and this probably directs the phosphoprotein to focal adhesions and the leading edge of stimulated cells. VASP functions as a binding intermediate between pr ofilin and focal adhesion proteins. Intracellular pathogens, including Listeria monocytogenes, have coat proteins which bind VASP. This is o ne way in which these pathogens use VASP, and other proteins from the host cell, to assemble the actin filaments they require to move around the cytoplasm of infected cells and enter neighbouring cells. Underst anding the role of VASP and other proteins in cell and bacterial motil ity is likely to lead to development of new therapeutic strategies for diseases including atherosclerosis and tumour growth, and for limitin g the spread of intracellular pathogens. (C) 1998 Elsevier Science Ltd . All rights reserved.