Isolation and identification of glycosaminoglycans associated with purified nuclei from rat liver

Nuclei isolated from rat liver were purified extensively and then subjected to extraction of glycosaminoglycans by the conventional method with a slight modification including the treatments with amylase, nucleases (DNAase and RNAase), and sialidase in addition to the pronase treatment. The nuclear glycosaminoglycan fraction thus prepared was subjected to chromatography on Dowes 1-X2 (Cl-) and electrophoresis before or after digestion with specific enzymes such as Streptomyces hyaluronidase, chondroitinase ABC and AC. These results together with the results of chemical analyses have revealed that the purified nuclei from rat liver contain glycosaminoglycans equivalent to 0.2-0.3 microgram hexuronic acid per mg DNA. A major component of the nuclear glycosaminoglycans has been identified as hyaluronic acid, while a minor component as chondroitin sulfate A (OR C). Preliminary investigations have shown that most of the nuclear glycosaminoglycans are associated with the chromatin fraction.