Extracellular matrix (ECM) plays a critical role in normal development, tissue repair, and is altered in several disease states. During these processes, expression of ECM genes is regulated temporally and spatially. Identification of regulatory elements that direct tissue- and stage-specific expression is important for understanding of the role of ECM genes in cellular differentiation and function. A significant number of ECM genes have been cloned and their regulatory elements have been identified. Reporter gene systems are widely used to study gene regulation and function (1-3). In this chapter, we describe methods for the identification of promoters and enhancers of cartilage collagen genes for theα1(II) andα2(XI) chains using transgenic mice and transient transfection in cell cultures (4-9).
