Using a pLX-304 vector, we generated a retrovirus encoding the GFP control and target gene Bmp7 cDNA to infect Runx1f/fCol1α1-Cre BMSCs after osteogenesis induction for 14 days, and we showed that Bmp7 was highly expressed post-infection (Fig 7C and S6B Fig), confirming that this retroviral system can sustain high gene expression for our overexpression studies. The gene discussed is BMP7; the disease is infection.