Fibrillin microfibrils: multipurpose extracellular networks in organismal physiology.

Organismal physiology depends significantly on the proper assembly of extracellular matrix (ECM) macroaggregates that impart structural integrity to the connective tissue. Recent genetic studies in mice have unraveled unsuspected new functions of architectural matrix components in regulating signaling events that modulate patterning, morphogenesis, and growth of several organ systems. As a result, a new paradigm has emerged whereby tissue-specific organization of the ECM dictates not only the physical properties of the connective tissue, but also the ability of the matrix to direct a broad spectrum of cellular activities through the regulation of growth factor signaling. These observations pave the way to novel therapeutic approaches aimed at counteracting the deleterious consequences of perturbations of connective tissue homeostasis.