Abstract
The dermal-epidermal basement membrane zone (BMZ) lies at the interface between the epithelium and underlying mesenchymal tissue. It is a highly organized structure with both similarities and differences compared to BMZs present in other tissues. In the skin, the BMZ serves many functions. Its architectural role includes providing stable dermal-epidermal cohesion and mechanical integrity of the skin. It also regulates and serves as a source of ligands/signaling molecules that bind to cellular receptors such as integrins, to influence cellular proliferation, migration, and differentiation. The BMZ of the skin is composed mainly of collagen and laminin networks, connected by proteoglycans/glycosaminoglycans, all of which can undergo degradation/activation by metalloproteinases. This chapter provides an overview on the wide variety of molecules found in the extracellular matrix (ECM) of the skin, with particular focus on the BMZ. The role of each molecule in normal as well as disease and developmental processes in the skin is explored in the chapter.