Focal adhesion kinase.

Focal adhesion kinase (FAK) is a member of a growing family of non-receptor protein tyrosine kinases. Though originally identified as a putative substrate for the oncogenic tyrosine kinase pp60v-src, it is now well-established that FAK tyrosine phosphorylation is induced by adhesion of cell surface integrins to extracellular matrix and by a variety of other extracellular factors including the ligands for receptor tyrosine kinases and for seven transmembrane domain G-protein-coupled receptors. FAK can associate with multiple cellular components including other focal adhesion-associated proteins and signalling molecules. FAK is localized to focal adhesions and is centrally implicated in the regulation of cell motility and adhesion. Knocking out the FAK gene in mice prevents normal embryonic development and is associated with loss of mesenchymal cell motility. Recent findings further suggest novel tissue-specific functions for FAK, particularly in the brain. These findings implicate FAK in the aberrant migration of cells in a variety of diseases and suggest that FAK may be a novel target for therapeutic strategies.