Project description:Purpose: Osteoblast cells mature from a mesenchymal stem cell pool to become cells capable of forming bone matrix and mineralizing this matrix. The goal of this study was to characterize temporal changes in the transcriptome across osteoblast maturation, starting with committed mesenchymal stem cell/ early pre-osteoblast stage through to mature osteoblasts capable of matrix mineralization. Methods: Enriched populations of pre-osteoblast like cells were obtained from neonatal calvaria from C57BL/6J mice expressing CFP under the control of the Col3.6 promoter. These cells were placed into culture for 4 days, removed from culture and subjected FACS sorting based on the presence/absence of CFP expression. Cells expressing CFP were returned to culture, subjected to an osteoblast differentiation cocktail and RNA was collected at 2, 4, 6, 8, 10, 12, 14, 16 and 18 days post differentiation. Methods II: mRNA profiles for each time point were generated by next generation RNA sequencing, using an Illumina HiSeq 2000. Three technical replicates per samples were sequenced. The alignments for abundance estimation of transcripts was conducted using Bowtie version 0.12.9, using the NCBIm37 reference genome. Expression level per gene was calculated using RSEM version 1.2.0 with the parameters of --fragment-length-mean 280 and --fragment-length-sd 50, and the expression level for each sample was normalized relative to the per sample upper quartile. Gene expression in calvarial osteoblasts from neonatal C57BL/6J-Col3.6 CFP mice at 9 time points post differentiation
Project description:Sp7/Osterix is a master regulator of osteoblast specification. To identify the Sp7-mediated gene regulatory network in osteoblasts, we performed Sp7 ChIP-seq on primary mouse calvarial osteoblasts comparing the DNA binding profile with the transcriptional profile of Sp7-positive osteoblasts. Analysis of these identified a network of Sp7 regulated osteoblast targets and provides a new insight into the mode of Sp7 action in osteoblast. To further study for the Sp7 mode, we performed ChIP-seq for Sp1, Sp7, Dlx5, as a potential Sp7 partner identified in this study and mutated Sp7 which has mutations in the zinc finger domain, by using in vitro system with a pre-osteoblast mouse cell line, MC3T3E1.
Project description:Sp7/Osterix is a master regulator of osteoblast specification. To identify transcripts profile in Sp7 positive osteoblast, we performed RNA-seq on primary mouse calvarial cells obtained from Sp7-GFP reporter mice at P1. By hierarchical clustering using transcriptional profiles for chondrocytes and mouse embryonic fibroblasts (MEFs) together with the osteoblast data, we identified cell-type enriched gene expression signatures in osteoblasts, chondrocytes and MEFs. In conjunction with Sp7 ChIP-seq in osteoblast, we identified putative Sp7 targets which underlie the osteoblast regulatory program.
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:To examine the unbiased global gene expression of gain of miR34c in committed osteoblast in mouse we have performed expression microarray. This approach will allow us to define the novel targets that are negatively regulated by over-expression of miR34c in osteoblast. Total RNA was isolated from primary calvaria from WT and GOF miR34c mouse (n=3) at the age of P3. WT primary calvarial samples were served as control.