DEVELOPMENTAL EXPRESSION IN THE RAT CEREBELLUM OF SC1, A PUTATIVE BRAIN EXTRACELLULAR-MATRIX GLYCOPROTEIN RELATED TO SPARC

In the nervous system, extracellular matrix (ECM) molecules have been shown to have effects on cell migration, process outgrowth and the sur vival of neurons. Recently we have described the molecular cloning of SC1, a putative brain extracellular matrix glycoprotein, showing parti al similarity to the ECM glycoprotein SPARC/osteonectin. We have now e xamined the expression of SC1 during the development of the rat cerebe llum at both the protein and mRNA levels. Our results indicate that SC 1 is both temporally and spatially regulated during this process. Berg mann glial cells express SC1 mRNA and the resultant protein is deposit ed along the length of their radial fibres during the process of granu le cell migration in the developing cerebellum SC1 mRNA and protein is also found in the adult cerebellum, concentrated in the Bergmann glia l cells and their radial processes, indicating that this putative ECM molecule continues to play roles in the central nervous system after m igration and proliferative events have ceased.