Effects Of QM On The Osteoblasts Cell Line MC3T3-E1

It has been reported that QM was highly expressed by cells isolated fromepiphyseal cartilage as opposed to proliferative chondrocytes. In vitro investigationof the expression of QM revealed higher QM expression in nonmineralizingosteoblast and pericyte cultures as compared with mineralizing cultures. Theseevidences suggest that QM may play an essential role in cell differentiation beforemineralization.In this study, RNA interference was used to examine the effects of silencingQM on the osteoblasts MC3T3-E1. After three days, many cells transfectedpSilencer3.1-H1/puro/QM vector began to die. Eight days later, majority of cellswere dead. Research results showed that the silence of QM led to the death ofMC3T3-E1. To further study the QM's role in bone formation and metabolizability,QM protein was overexpressed in MC3T3-E1 by transfecting cells withpcDNA3.1/myc-His A/QM vector. When overexpressed of QM, alkalinephosphatase activity and nodule mineralization were both increased in MC3T3-E1from QM overexpression cultures relative to normal expression QM cultures.RT-PCR revealed upregulation of the marker genes related to cells growth,differentiation and mineraliztion. However, cell cycle was not changed verysignificantly determined by Flow cytometer. These results suggest that theincreasing of QM expression could stimulate osteoblast differentiation andmineralization in MC3T3-E1.This study offers the scientific basis of the study of potential roles of QM in theprocess of bone formation. Furthermore this research work also provides a new ideain screening medicines on the therapy of osteoporosis.