Identification and Characterization of Cellular Binding Proteins (Receptors) for Recombinant Human Bone Morphogenetic Protein 2B, an Initiator of Bone Differentiation Cascade
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 2B-respon...
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Published in | Proceedings of the National Academy of Sciences - PNAS Vol. 88; no. 8; pp. 3397 - 3401 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Washington, DC
National Academy of Sciences of the United States of America
15.04.1991
National Acad Sciences |
Subjects | |
Online Access | Get full text |
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Summary: | 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 2B-responsive cells for the presence of specific cellular binding proteins. Using125I-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 E1 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 E1 cells. These data demonstrate specific, high-affinity cell-surface binding proteins for BMP 2B. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0027-8424 1091-6490 |
DOI: | 10.1073/pnas.88.8.3397 |