TY - JOUR
T1 - Identification and characterization of cellular binding proteins (receptors) for recombinant human bone morphogenetic protein 2B, an initiator of bone differentiation cascade
AU - Paralkar, Vishwas M.
AU - Hammonds, R. Glenn
AU - Reddi, A Hari
PY - 1991
Y1 - 1991
N2 - Bone morphogenetic protein 2B (BMP 2B), is a heparin-binding bone differentiation factor that initiates endochondral bone formation in rats when implanted subcutaneously. The molecular mechanism of action of this differentiation factor is not known, and as a first step we have examined BMP 26-responsive cells for the presence of specific cellular binding proteins. Using 125I-labeled BMP 2B, specific high-affinity binding sites for recombinant human BMP 2B on MC3T3 E1 osteoblast-like cells as well as on NIH 3T3 fibroblasts were identified. Platelet-derived growth factor, insulin-like growth factor 1, basic fibroblast growth factor, epidermal growth factor, and transforming growth factor β did not compete for the binding of radiolabeled BMP 2B. The binding of BMP 2B is a time- and temperature-dependent process. Chemical crosslinking of radiolabeled BMP showed two components (apparent size, 200 and 70 kDa in MC3T3 El cells and 200 and 90 kDa in NIH 3T3 cells). A minor component at 60 kDa was also detected in both cell lines. Scatchard analysis of the binding data showed a high-affinity receptor with an apparent dissociation constant of 128 ± 40 pM in MC3T3 El cells. These data demonstrate specific, high-affinity cell-surface binding proteins for BMP 2B.
AB - Bone morphogenetic protein 2B (BMP 2B), is a heparin-binding bone differentiation factor that initiates endochondral bone formation in rats when implanted subcutaneously. The molecular mechanism of action of this differentiation factor is not known, and as a first step we have examined BMP 26-responsive cells for the presence of specific cellular binding proteins. Using 125I-labeled BMP 2B, specific high-affinity binding sites for recombinant human BMP 2B on MC3T3 E1 osteoblast-like cells as well as on NIH 3T3 fibroblasts were identified. Platelet-derived growth factor, insulin-like growth factor 1, basic fibroblast growth factor, epidermal growth factor, and transforming growth factor β did not compete for the binding of radiolabeled BMP 2B. The binding of BMP 2B is a time- and temperature-dependent process. Chemical crosslinking of radiolabeled BMP showed two components (apparent size, 200 and 70 kDa in MC3T3 El cells and 200 and 90 kDa in NIH 3T3 cells). A minor component at 60 kDa was also detected in both cell lines. Scatchard analysis of the binding data showed a high-affinity receptor with an apparent dissociation constant of 128 ± 40 pM in MC3T3 El cells. These data demonstrate specific, high-affinity cell-surface binding proteins for BMP 2B.
KW - Bone cells
KW - Cartilage
KW - Development
KW - Morphogenesis
KW - Transforming growth factor β superfamily
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M3 - Article
C2 - 1849655
AN - SCOPUS:0026351807
VL - 88
SP - 3397
EP - 3401
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 8
ER -