Abstract
Extracellular matrices are formed as networks of stable and dynamic interactions between macromolecules. Such interactions provide connective tissues with specific biomechanical properties and may also regulate cellular activities. Fibromodulin, the matrix glycoprotein discussed in this article, is found in many connective tissues where it appears to be primarily associated with fibrillar collagen. The amino acid sequence of its 39kDa core protein shows extensive homology with the collagenbinding proteoglycans, decorin and lumican. Fibromodulin contains five N-linked glycosylation sites which are substituted in a developmentally regulated manner with polylactosamine chains of variable structure and sulfation pattern. These structural characteristics of fibromodulin are discussed, and it is suggested that this member of the group of small interstitial proteoglycans may serve additional functions beyond its proposed role in the modulation of collagen fibrillogenesis.
