Focal adhesion kinase(FAK), with 1074 -amino acid protein(about 118 kDa), is a member of the FAK subfamily of protein tyrosine kinases but lacks significant sequence similarity to kinases from other subfamilies. FAK is concentrated at the basal edge of only basal keratinocytes that are actively migrating and rapidly proliferating in repairing burn wounds, and is activated and localized to the focal adhesions of spreading keratinocytes in culture. Thus, it has been postulated that FAK may have an important in vivo role in the re-epithelialization of human wounds. FAK protein tyrosine kinase activity has also been shown to increase in cells stimulated to grow by use of mitogenic neuropeptides or neurotransmitters acting through G protein-coupled receptors.