Genome wide gene expression profiling of Col2.3GFP+ enriched osteoblasts

We identified 593 candidate genes that are highly enriched in Col2.3GFP+ osteoblasts. Gene Ontology analysis revealed that these 593 genes are highly enriched in endochondral ossification, collagen fibril organization, positive regulation of osteoblast differentiation, and regulation of bone mineralization. The top 3 annotation terms are all associated with endoplasmic reticulum (ER) and Golgi vesicle transport. Furthermore, we have identified several vesicle trafficking genes with roles in osteoblast differentiation and function. Using Col2.3GFP transgenic mice that express green fluorescent protein (GFP) in osteoblasts, we isolated Col2.3GFP+ enriched osteoblasts from three sources: 1) in vivo freshly isolated from mouse long bone; 2) ex vivo isolated from mouse bone chip culture; and 3) in vitro directed differentiation from mouse embryonic stem cells (ESCs). We performed RNA-sequencing and identified 593 overlapping genes that are highly enriched in Col2.3GFP+ osteoblasts from all three sources.