title: Structural properties of the heparan sulfate proteoglycans of brain.
abstract: The heparan sulfate proteoglycans present in a deoxycholate extract of rat brain were purified by ion exchange chromatography, affinity chromatography on lipoprotein lipase agarose, and gel filtration. Heparitinase treatment of the heparan sulfate proteoglycan fraction (containing 86% heparan sulfate and 10% chondroitin sulfate) that was eluted from the lipoprotein lipase affinity column with 1 M NaCl led to the appearance of a major protein core with a molecular size of 55,000 daltons, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Comparison of the effects of heparinase and heparitinase treatment revealed that the heparan sulfate proteoglycans of brain contain a significant proportion of relatively short N-sulfoglucosaminyl 6-O-sulfate [or N-sulfoglucosaminyl](alpha 1-4)iduronosyl 2-O-sulfate(alpha 1-4) repeating units and that the portions of the heparan sulfate chains in the vicinity of the carbohydrate-protein linkage region are characterized by the presence of D-glucuronic acid rather than L-iduronic acid. After chondroitinase treatment of a proteoglycan fraction that contained 62% chondroitin sulfate and 21% heparan sulfate (eluted from lipoprotein lipase with 0.4 M NaCl), the charge and density of a portion of the heparan sulfate-containing proteoglycans decreased significantly. These results indicate that a population of "hybrid" brain proteoglycans exists that contain both chondroitin sulfate and heparan sulfate chains covalently linked to a common protein core.
authors.affiliation: Department of Pharmacology, New York University Medical Center, NY 10016.
authors.forename: J A
authors.initials: JA
authors.lastname: Ripellino
authors.forename: R U
authors.initials: RU
authors.lastname: Margolis
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002499:Centrifugation, Density Gradient; D055598:Chemical Phenomena; D002621:Chemistry; D011508:Chondroitin Sulfate Proteoglycans / Q000302:isolation & purification* / Q000378:metabolism; D002809:Chondroitin Sulfates / Q000032:analysis; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D006025:Glycosaminoglycans / Q000302:isolation & purification*; D019812:Heparan Sulfate Proteoglycans; D019763:Heparin Lyase; D006497:Heparan Sulfate / Q000032:analysis / Q000302:isolation & purification* / Q000378:metabolism; D015394:Molecular Structure; D008970:Molecular Weight; D011133:Polysaccharide-Lyases / Q000378:metabolism; D055503:Protein Multimerization; D011509:Proteoglycans / Q000302:isolation & purification*; D051381:Rats; D013431:Sulfates / Q000378:metabolism
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; D002809:Chondroitin Sulfates; D006025:Glycosaminoglycans; D019812:Heparan Sulfate Proteoglycans; D019763:Heparin Lyase; D006497:Heparan Sulfate; D011133:Polysaccharide-Lyases; D011509:Proteoglycans; D013431:Sulfates; C021349:heparitinsulfate lyase