The interferon-inducible protein p202 promotes osteogenesis in mouse bone marrow stromal cells.

In the present study, we explored the role of the interferon-inducible protein p202 in osteoblast differentiation of mouse bone marrow stromal cells (BMSCs). Both the mRNA and protein levels of p202 increased initially and decreased afterward in the course of BMSC osteogenesis. The intracellular distribution of this protein also changed in the differentiation process. p202 knockdown inhibited, while p202 overexpression enhanced, the osteoblast differentiation of BMSCs. This was identified by evaluation of expression of osteogenic markers, Alizarin Red S staining, and determination of alkaline phosphatase activity. Further study revealed that p202 disturbs the formation of Runx2/Ids complex and frees Runx2 to induce the differentiation process. The findings demonstrated that p202 plays a positive role in BMSC osteogenesis.