Characterization and distribution of hyaluronan and the proteoglycans decorin, biglycan and perlecan in the developing embryonic mouse gonad.

The morphogenesis of tissues and organs requires dynamic changes in cells and in extracellular matrix components. It is known that various extracellular matrix molecules are of fundamental importance for gonad differentiation and growth. In the adult testis, the extracellular matrix represents an important component of the interstitium, participating in the transport of biologically active substances needed for the communication between different cellular components, as well as for the regulation of spermatogenesis and hormone production. The present study was designed in order to identify the proteoglycans biglycan, decorin and perlecan, as well as the glycosaminoglycan hyaluronan, during testis development in mouse embryos. Our data profile the chronology of testis differentiation, as well as the distribution of these extracellular matrix components during testis development in mice. We show that these extracellular matrix molecules are present early in the development of the gonads, suggesting that they play a role in gonad development. In addition, we found no decorin in the testicular cords. Furthermore, of the proteoglycans analysed, only biglycan was seen surrounding immature Sertoli cells and Leydig cell precursors in the testicular cords. This indicates that specific sets of extracellular matrix molecules are required in the various compartments of the developing gonad.