ABSTRACT
Integrins are heterodimeric transmembrane receptors that mediate cell-adhesion.1 With their extracellular head region, most integrins bind extracellular matrix (ECM) glycoproteins such as laminins and collagens in basement membranes or connective tissue components like fibronectin. Others bind counterreceptors on neighboring cells, bacterial polysaccharides, or viral coat proteins. Through all these interactions integrins mediate stable adhesion to basement membranes, the formation of extracellular matrices and migration on such matrices, the formation of platelet aggregates, the establishment of intercellular junctions in the immune system, and bacterial and viral entry during infectious diseases. Furthermore, integrin-mediated adhesion modulates signaling cascades in control of cell motility, survival, proliferation, and differentiation. Here, a brief overview of basic structure/function aspects of integrins is given with the aim of providing background information for the following chapters in this book.
