[Intracellular distribution of tyrosine-phosphorylated actin-binding proteins in A431 cells spread on different ligands].

Spreading A431 cells on extracellular matrix elements fibronectin, laminin 2/4 and antibody to EGF receptor (5A9 clone) leads to tyrosine phosphorylation of actin-binding proteins, which participate in focal adhesions formation. Tyrosine phosphorylation of the proteins is retained for 1 h of cell spreading. When cells interact with ligands, focal adhesion kinase (FAK) becomes tyrosine phosphorylated, and eventually phosphorylates the target proteins. The cooperative effect of integrins and EGF receptor in FAK autophosphorylation at cell spreading on antibody to EGF receptor is discussed.