Identification of a vitamin D-responsive protein on the surface of human osteosarcoma cells.
AUTOR(ES)
Shull, S
RESUMO
Monoclonal antibodies were elicited to membrane constituents of the osteoblastic human osteosarcoma cell line Saos-2. Two types of antibody reactivities were characterized: one group of antibodies identified fibroblastic and osteoblastic cultured cells, whereas the other group was specific for the parent cell line, Saos-2. Primary endothelial cells and hepatoma cells were not recognized by either group of antibodies. Through indirect immunofluorescent microscopy, the Saos-2-specific antigen was demonstrated to reside on the surface of these osteosarcoma cells. Metabolic radiolabeling of cultured Saos-2 cells and subsequent immunoprecipitation, electrophoretic separation, and autoradiography revealed this protein to have a Mr of 80,000. Similar experiments in the presence of hormones showed that the expression of this cell surface protein was influenced in an opposing fashion by the bone-regulating hormones parathyroid hormone and vitamin D. Vitamin D stimulated expression by 300%, whereas parathyroid hormone depressed expression by 50%. Thus, Saos-2 human osteoblastic cells demonstrate hormonal regulation through an apparently specific membrane protein.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=297631Documentos Relacionados
- Vitamin D-responsive rickets in neonatal lambs
- Reconstitution of the vitamin D-responsive osteocalcin transcription unit in Saccharomyces cerevisiae.
- Vitamin D-responsive protein-DNA interactions at multiple promoter regulatory elements that contribute to the level of rat osteocalcin gene expression.
- Postproliferative transcription of the rat osteocalcin gene is reflected by vitamin D-responsive developmental modifications in protein-DNA interactions at basal and enhancer promoter elements.
- Multiple Cbfa/AML Sites in the Rat Osteocalcin Promoter Are Required for Basal and Vitamin D-Responsive Transcription and Contribute to Chromatin Organization