The overall goal of the research is to understand the developmental processes that take place in Chip embryonic limb. In this developmental system, changes occur in the activity of a number of genes at the time of differentiation of limb mesodermal cells into chondrocytes. We will study: a) the structure-function relationship of the translation products of newly activated genes in the establishment of the cartilaginous matrix, b) the regulatory sequences that are specific for the expression of one of these genes in chondrocytes and c) the morphogenetic consequences of induced and spontaneous mutations that affect cartilage matrix macromolecules.