title: The amino-terminal region of a proteochondroitin core protein, secreted by aortic smooth muscle cells, shares sequence homology with the pre-propeptide region of the biglycan core protein from human bone.
abstract: Smooth muscle cells, isolated from rat and bovine aortae and grown in vitro, synthesize chondroitin sulfate proteoglycans which are secreted into the growth media. Analysis of metabolically [35S]-labeled macromolecules, employing ion-exchange chromatography, revealed a single peak of radioactivity, upon elution with a linear salt gradient. Treatment of the material with enzymes that specifically degrade chondroitin sulfate demonstrated that chondroitin-4-sulfate was the predominant species isolated from rat smooth muscle cells and that chondroitin-4-sulfate and dermatan sulfate were the predominant species isolated from bovine aortic smooth muscle cells. Treatment of the native proteoglycans with chondroitinase ABC and subsequent SDS-PAGE analysis of the digestion products resulted in the appearance of a band with an apparent molecular weight of 45,000. Electrotransfer of the core protein to Immobilon-P membrane and gas phase sequencing of the amino-terminal region revealed striking homology between the core proteins of the rat and bovine proteochondroitin with the pre-propeptide region of human bone biglycan.
authors.affiliation: Department of Pathology, Beth Israel Hospital, Harvard Medical School, Boston, MA 02215.
authors.forename: J A
authors.initials: JA
authors.lastname: Marcum
authors.forename: M A
authors.initials: MA
authors.lastname: Thompson
mesh_terms: D053674:Aggrecans; D000595:Amino Acid Sequence; D000818:Animals; D058578:Biglycan; D001842:Bone and Bones / Q000737:chemistry; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins / Q000737:chemistry*; D006801:Humans; D037181:Lectins, C-Type; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009131:Muscle, Smooth, Vascular / Q000737:chemistry; D011509:Proteoglycans / Q000737:chemistry*; D051381:Rats
chemical_list: C508321:Acan protein, rat; D053674:Aggrecans; C546884:BGN protein, human; C546886:Bgn protein, rat; D058578:Biglycan; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D037181:Lectins, C-Type; D011509:Proteoglycans