Project description:The goal of this study is to compare next-generation sequencing-derived osteoblast transcriptome profilings to identify essential genes during isteoblast differnetiation.
Project description:In order to identify genes with differential expression in primary murine osteoblasts we compared the transcriptomes of these cells at day 5 and day 12 of differentiation
Project description:In order to identify genes with differential expression in primary murine osteoblasts we compared the transcriptomes of these cells at day 5 and day 12 of differentiation CD11b-negative cells derived from calvariae of newborn mice were differentiated into osteoblasts by addition of ascorbic acid and ß-glycerophosphate for 5 or 12 days.
Project description:Differentiation of human skeletal stem cells (hMSC) into osteoblasts is regulated by a few well described transcription factors. Our study used clustering and gene expression data to identify a novel transcription factor. ZNF25, which we showed is involved in osteoblast differentiation. We used microarrays to study gene expression of hMSC-TERT4 cells during osteoblast differentiation.
Project description:The biological effects of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) on osteoblast differentiation and function differ significantly depending upon the cellular state of maturation. To explore this phenomenon mechanistically, we examined the impact of 1,25(OH)2D3 on the transcriptomes of both pre-osteoblastic (POBs) and differentiated osteoblastic (OBs) MC3T3-E1 cells, and assessed localization of the vitamin D receptor (VDR) at sites of action on a genome-scale using ChIP-seq analysis. We observed that the 1,25(OH)2D3-induced transcriptomes of POBs and OBs were quantitatively and qualitatively different, supporting not only the altered biology observed but the potential for a change in VDR interaction at the genome as well. This idea was confirmed through discovery that VDR cistromes in POBs and OBs were also strikingly different. Depletion of VDR binding sites in OBs, due in part to reduced VDR expression, was the likely cause of the loss of VDR-target gene interaction. Continued novel regulation by 1,25(OH)2D3, however, suggested that factors in addition to the VDR might also be involved. Accordingly, we show that transcriptomic modifications are also accompanied by changes in genome binding of the master osteoblast regulator RUNX2 and the chromatin remodeler C/EBPβ. Importantly, genome occupancy was also highlighted by the presence of epigenetic enhancer signatures which were selectively changed in response to both differentiation and 1,25(OH)2D3. The impact of VDR, RUNX2, and C/EBPβ on osteoblast differentiation is exemplified by their actions at the Runx2 and Sp7 gene loci. We conclude that each of these mechanisms may contribute to the diverse actions of 1,25(OH)2D3 on differentiating osteoblasts. RNA was isolated and applied to gene expression microarrays in undifferentiated MC3T3-E1 cells as well as post 15 day osteogenic differentiation MC3T3-E1 cells, which were treated for 24 hours with 10-7M 1,25(OH)2D3. For the vehicle matched samples, please refer to study GSE41955. The samples were completed in biological triplicate.
Project description:The biological effects of 1?,25-dihydroxyvitamin D3 (1,25(OH)2D3) on osteoblast differentiation and function differ significantly depending upon the cellular state of maturation. To explore this phenomenon mechanistically, we examined the impact of 1,25(OH)2D3 on the transcriptomes of both pre-osteoblastic (POBs) and differentiated osteoblastic (OBs) MC3T3-E1 cells, and assessed localization of the vitamin D receptor (VDR) at sites of action on a genome-scale using ChIP-seq analysis. We observed that the 1,25(OH)2D3-induced transcriptomes of POBs and OBs were quantitatively and qualitatively different, supporting not only the altered biology observed but the potential for a change in VDR interaction at the genome as well. This idea was confirmed through discovery that VDR cistromes in POBs and OBs were also strikingly different. Depletion of VDR binding sites in OBs, due in part to reduced VDR expression, was the likely cause of the loss of VDR-target gene interaction. Continued novel regulation by 1,25(OH)2D3, however, suggested that factors in addition to the VDR might also be involved. Accordingly, we show that transcriptomic modifications are also accompanied by changes in genome binding of the master osteoblast regulator RUNX2 and the chromatin remodeler C/EBP?. Importantly, genome occupancy was also highlighted by the presence of epigenetic enhancer signatures which were selectively changed in response to both differentiation and 1,25(OH)2D3. The impact of VDR, RUNX2, and C/EBP? on osteoblast differentiation is exemplified by their actions at the Runx2 and Sp7 gene loci. We conclude that each of these mechanisms may contribute to the diverse actions of 1,25(OH)2D3 on differentiating osteoblasts. 4 transcription factors and 5 histone modifications were examined in undifferentiated MC3T3-E1 cells as well as post 15 day osteogenic differentiation MC3T3-E1 cells, which were treated for 3 hours prior to ChIP assay with ethanol vehicle or with 10-7M 1,25(OH)2D3. For the vehicle matched samples for RUNX2, CEBP beta and histones, please refer to study GSE41955. The samples were completed in biological replicate and examined separately.