Growth factors regulate proliferation and cellular activities that result in coordinated growth and differentiation of animal tissues. To achieve their effects, growth factors regulate gene expression and thus the production of new proteins. Proteins that are secreted are often involved in coordinating cell growth in multicellular tissues. Dr. Nilsen-Hamilton has discovered several secreted proteins that are regulated by growth factors. The research team is exploring the mechanisms by which the genes that encode these proteins are regulated and the functions of these proteins in controlling controlling cell functions.