The applicants propose to use an integrated molecular based approach to study the influence of biomaterial surface chemistry on cell signaling and proliferation pathways relevant to tissue engineering and biomaterials development. The long term objective of the studies is to correlate specific cell biology and genetic responses which are important to Specifically, the applicants will first test the hypothesis that molecular level control of biomaterial surface chemistry has a profound impact upon cell transmembrane signaling events. Using a well studied array of organic self assembled film components, they will attempt to explain the observation that cells cultured on these various surfaces exhibit certain surface chemistry-dependent growth and attachment patterns. Experiments are directed at signal-activated protein phosphorylation and focal adhesions. Secondly, the applicants will investigate integrin mediated regulation of the formation of focal contacts, stress fibers and subsequent pathways for genetic regulation of cell proliferation. Thirdly, the applicants will use cells which have been transfected with either constitutively active or constitutively inactive Rho mutants, and will then assess the ability of cells to attach, form focal contacts and stress fibers and regulate growth specific genes such as c-myc, creb, c-fos, and c-jun on various surfaces. Genetic engineering methods will then be used to assay the endpoint of cell signaling cascade in response to various surfaces. The applicants claim this approach will enable the development of bioassays of cellular responses to biomaterials that are both diagnostic of a material's intrinsic ability to support cell growth and will provide information which is fundamental to understanding the responses of cells to biomaterials.