title: Characterization of the non-collagenous proteins in avian cortical and medullary bone.
abstract: Northern blotting, RT-PCR, and Western blotting techniques were used to characterize the matrix constituents of avian cortical and medullary bone. Extracts of bone tissue were found to contain multiple isoforms of bone sialoprotein (BSP), osteopontin (OPN), osteonectin (ON), osteocalcin (OC), and dentin matrix protein-1 (DMP-1). Only single transcripts were observed with Northern blotting; therefore it was concluded that the isoforms were due to differences in post-translational modifications. Since medullary bone is rich in keratan sulfate (KS), RT-PCR was used to investigate the expression of known keratan sulfate-containing proteoglycans (KSPGs). Although this tissue was found to express lumican and osteoglycin/mimecan, there was little evidence to suggest that these proteoglycans were a major source of the keratan sulfate glycosaminoglycans. Treatment of medullary bone extracts with keratanase resulted in the appearance of a BSP immunoactive band of approximately 59 kDa. However, it was not possible to isolate and identify the intact keratan sulfate proteoglycan.
authors.affiliation: Department of Poultry Science, 205 William L. Henning Building, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Xibin
authors.initials: X
authors.lastname: Wang
authors.forename: Bonnie C
authors.initials: BC
authors.lastname: Ford
authors.forename: Craig A
authors.initials: CA
authors.lastname: Praul
authors.forename: Roland M
authors.initials: RM
authors.lastname: Leach
mesh_terms: D000818:Animals; D001717:Birds / Q000033:anatomy & histology*; D015152:Blotting, Northern; D015153:Blotting, Western; D001842:Bone and Bones / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry*; D058574:Integrin-Binding Sialoprotein; D007632:Keratan Sulfate / Q000737:chemistry; D015675:Osteocalcin / Q000737:chemistry; D015676:Osteonectin / Q000737:chemistry; D053495:Osteopontin; D010750:Phosphoproteins / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D011509:Proteoglycans / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000737:chemistry
chemical_list: C546873:Ibsp protein, rat; D058574:Integrin-Binding Sialoprotein; D015676:Osteonectin; D010750:Phosphoproteins; D011506:Proteins; D011509:Proteoglycans; D012795:Sialoglycoproteins; C506897:Spp1 protein, rat; D015675:Osteocalcin; D053495:Osteopontin; D003094:Collagen; D007632:Keratan Sulfate