FIGURE 5.

Limited C-terminal cleavage of aggrecan with clostripain protease. Aggrecan, either as a free monomer (A and B) or in an aggregate bound to HA (C and D), was digested for 0–30 min with clostripain protease and then evaluated directly by electrophoresis on 1% agarose gels stained with DMMB. Individual clostripain-digested monomer fractions (as in A) were next incubated with HA to reconstitute aggregates and re-evaluated on agarose gels (B). Individual clostripain-digested aggregate fractions (as in C) were subsequently treated with Streptomyces hyaluronidase to degrade the HA and return the aggrecan to monomers, and they were re-evaluated on agarose gels (D). Shown are representative images from four experiments. A 1-kb DNA ladder standard (S) was used for reference and alignment of the gel.