Connective Tissue Pathways that Regulate Growth Factors

This chapter summarizes current knowledge about fibrillin microfibrils, their molecular partners in the connective tissue, and their relevance to skeletal biology. Some proteins associated with fibrillin microfibrils include elastin, the fibulins, MAGPs, perlecan, versican, decorin, and biglycan. These associated proteins establish connective tissue pathways that extend from the fibrillin microfibril networks to basement membranes (through perlecan interactions) and from proteoglycan shells around the microfibrils to hyaluronan and to collagen. These connective tissue pathways integrate fibrillin microfibril networks into the histological patterns of specific organs (cartilage and bone compared with muscle and skin) and into the mechanical and physiological properties of specific organs. More sophisticated mouse models are required in order to dissect the mechanisms by which the microfibril scaffold regulates growth factor signaling and by which human pathologies are produced.