Dermatan sulphate proteoglycans of human articular cartilage. The properties of dermatan sulphate proteoglycans I and II

Abstract

Dermatan sulphate proteoglycans were purified from juvenile human articular cartilage, with a yield of about 2 mg/g wet wt. of cartilage. Both dermatan sulphate proteoglycan I (DS-PGI) and dermatan sulphate proteoglycan II (DS-PGII) were identified and the former was present in greater abundance. The two proteoglycans could not be resolved by agarose/polyacrylamide-gel electrophoresis, but could be resolved by SDS/polyacrylamide-gel electrophoresis, which indicated average Mr values of 200,000 and 98,000 for DS-PGI and DS-PGII respectively. After digestion with chondroitin ABC lyase the Mr values of the core proteins were 44,000 for DS-PGI and 43,000 and 47,000 for DS-PGII, with the smaller core protein being predominant in DS-PGII. Sequence analysis of the N-terminal 20 amino acid residues reveals the presence of a single site for the potential substitution of dermatan sulphate at residue 4 of DS-PGII and two such sites at residues 5 and 10 for DS-PGI.

Bone Morphogenetic Protein-1 Processes Probiglycan

“…4A), was isolated and subjected to automated Edman degradation for determination of NH 2 -terminal amino acid sequences. Ten cycles of Edman degradation produced a sequence identical to the published human biglycan sequences that occur just COOH-terminal of the N-propeptide and corresponding to the NH 2 terminus of mature biglycan isolated from tissues (15,26,28,29). Thus, BMP-1 processes probiglycan at the physiologically relevant site.…”

“…Molecular masses are indicated for protein standards. B, alignment of the NH 2 -terminal amino acid residues of the cleavage product resulting from BMP-1 cleavage of probiglycan, as determined by automated Edman degradation, with the published human probiglycan sequence deduced from cDNA and the physiological site at which proteolytic cleavage removes the N-propeptide in vivo (denoted by an arrow) to produce the mature tissue form of biglycan (15,26,28,29). Edman degradation assigned all residues with highest confidence except for the Ser at position 5, which, with a yield lower than expected based upon the yield of Ser at position 10, was assigned as probable and is indicated by brackets.…”

Expression of Small Extracellular Chondroitin/Dermatan Sulfate Proteoglycans Is Differentially Regulated in Human Endothelial Cells

“…Antisera-Biglycan antiserum was a polyclonal antiserum made in a rabbit against a synthetic peptide of human biglycan (amino acids [11][12][13][14][15][16][17][18][19][20][21][22][23][24] that was conjugated to bovine serum albumin before injections (5). This antiserum, called LF-51, was kindly provided by Dr. L. Fisher (National Institute of Dental Research, Bethesda, MD).…”

“…Biglycan is usually substituted with two GAG chains, whereas decorin typically has only one GAG chain (10 -12). On sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) biglycan has variously been shown to migrate at positions of protein molecular weight markers of ϳ200,000 or more, while decorin migrates at positions of protein molecular weight markers of 87,000 -180,000 (13)(14)(15)(16)(17). The third small extracellular CS/DS PG species, originally isolated from the culture medium of human osteosarcoma cells and tentatively named PG-100 (7), has recently been demonstrated to be identical with the macrophage colony-stimulating factor CSF-1 (18).…”

Glycosaminoglycan chains of biglycan promote bone morphogenetic protein-4-induced osteoblast differentiation

“…Biglycan (BGN), a member of the SLRP family, consists of a 45 kDa protein core and 2 glycosaminoglycan (GAG) chains, chondroitin sulfate (CS) and dermatan sulfate (DS), which are covalently linked to the protein core (2). The CS/DS chains are attached at amino acids 5 and 10 in the human BGN core protein (3). BGN is highly expressed in the ECM of bone and is localized on the surface of osteoblasts (4).…”