Proteoglycans of human articular cartilage. Identification of several populations of large and small proteoglycans and of hyaluronic acid-binding proteins in successive cartilage extracts.
Two specimens of human articulage were successively extracted with solutions of phosphate-buffered saline (PBS), 7 M-urea and 4 M-guanidine hydrochloride (Gdn-HCl). Proteoglycans from individual extracts were fractionated by DEAE-Sephacel chromatography and gel chromatography on Sephacryl S-400. The presence of three populations of large proteoglycans was demonstrated in all three extracts by composite agarose/polyacrylamide-gel electrophoresis (CAPAGE). The population corresponding to the fastest CAPAGE band of aggregating proteoglycans was shown to be extremely polydisperse, having Mr (as estimated by SDS/PAGE) decreasing continuously from more than 300,000 to the size corresponding to 'free' hyaluronic acid-binding region (HABR) (about 70,000). A rather polydisperse set of HABR-containing fragments which spanned a broad range of sizes, and also differed in their keratan sulphate contents, was isolated from both 7 M-urea and 4 M-Gdn-HCl extracts. PBS and 7 M-urea extracts, but not the Gdn-HCl extract, further contained small proteoglycans, identified as fast-migrating bands on CAPAGE electrophoretograms. One of those small species was recognized with an antibody against the small proteoglycan PG II; the other two remain to be positively identified. However, the glycosaminoglycan of the small species which was present exclusively in the PBS extract was identified as keratan sulphate; this species may thus belong to the family of small keratan sulphate-containing proteolygans.
Vilim
V
V
Research Institute of Rheumatology, Praha, Czechoslovakia.
Krajickova
J
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002352:Carrier Proteins / Q000302:isolation & purification* / Q000378:metabolism; D002358:Cartilage, Articular / Q000737:chemistry*; D002850:Chromatography, Gel / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006025:Glycosaminoglycans / Q000302:isolation & purification; D006801:Humans; D018960:Hyaluronan Receptors; D006820:Hyaluronic Acid / Q000378:metabolism; D015151:Immunoblotting; D008970:Molecular Weight; D011509:Proteoglycans / Q000302:isolation & purification*
D002352:Carrier Proteins; D006025:Glycosaminoglycans; D018960:Hyaluronan Receptors; D011509:Proteoglycans; D006820:Hyaluronic Acid