cDNA cloning and the identification of an aggrecanase-like cleavage site in rat brevican

Brevican is a member of the aggrecan family of chondroitin sulfate proteoglycans that is predominantly expressed in the nervous system. In the adult brain, the brevican core protein undergoes proteolytic cleavage and exists as a 145-kDa full-length form and an 80-kDa C-terminal fragment. We have determined the complete primary structure of rat brevican and the N-terminal amino acid sequence of the 80-kDa fragment. The results demonstrate that the cleavage of the brevican core protein occurs in a highly conserved region within a generally poorly conserved central domain, and that the sequence at the cleavage site shows intriguing similarities to the "aggrecanase" cleavage site in aggrecan. cDNA cloning of rat brevican has also revealed that the putative hyaluronic acid binding protein, BEHAB, is identical to the N-terminal half of brevican.