Project description:Osteoblasts are key players in bone remodeling. The accessibility of human primary osteoblast-like cells (HOb) from bone explants render them a lucrative model for studying molecular physiology of bone turnover, discovery of novel anabolic therapeutics and mesenchymal cell biology in general. Relatively little is known about resting and dynamic expression profiles of HObs and no studies have been conducted to date to systematically assess the osteoblast transcriptome. The aim of this study was to characterize HObs and investigate signaling cascades and gene networks using genomewide expression profiling in resting and Bone Morphogenic Protein (BMP)-2 and Dexamethasone induced cells. Our data showed a vast number of genes and networks expressed predominantly in HObs as compared to closely related cells such as fibroblasts or chondrocytes. For instance, genes in the insulin-like growth factor (IGF) signaling pathway were enriched in HObs (p=0.003) and included the binding proteins (IGFBP1, 2, 5) and IGF-2 and its receptor. Another HOb specific expression pattern included leptin and its receptor (p<10-8). Furthermore, after stimulating HObs with Dexamethasone or BMP-2, the expression of several interesting genes and pathways were observed where data supported the role of peripheral leptin signaling in bone cell function. In conclusion, we provide the landscape of tissue-specific and dynamic gene expression in HObs, a resource, which will allow utilization of osteoblasts as a model to study specific gene networks and gene families related to human bone physiology and diseases. Keywords: cell type comparison
Project description:Primary calvaria osteoblasts from newborn mice were cultured. Cells were transfected with control and miR-195 mimic. Following serum starvation cells were treated with recombinant human BMP2 and expression was analyzed 4 hours after treatment. Additionally, osteoblast differentiation was induced with osteogenic medium. Cells were analyzed at confluence (day 0) and 9 days later (day 9).