ABSTRACT
[ ABSTRACT] AIM:To study the expression profiles and the role of Ca 2+/calmodulin-dependent kinase II delta ( CaMKIIδ) during osteoclast differentiation .METHODS:Mouse RAW264.7 cells were induced by receptor activator of nuclear factor κB ligand ( RANKL) at 50μg/L for osteoclastogenesis .Tartrate-resistant acid phosphatase ( TRAP) staining and bone resorption lacunae examination were performed to verify osteoclast formation .The expression of CaMKIIδat mR-NA and protein levels was also determined by immunofluorescent cytochemistry , RT-qPCR and Western blot at days 0, 1, 3 and 5.RESULTS:TRAP positive multinuclear cells with bone resorption function were formed after 5 d of induction. The mRNA levels of CaMKIIδdetected by RT-qPCR were 1.028 ±0.041, 2.478 ±0.087, 10.524 ±1.284 and 42.914 ± 2.667 at days 0, 1, 3 and 5, respectively, while the protein levels of CaMKIIδ detected by Western blot were 0.762, 0.963, 1.802 and 3.136, respectively.The changes of protein level were also verified by immunofluorescence cytochemis -try, in which the fluorescence intensity increased in a time-dependent manner (P<0.05).CONCLUSION:The expres-sion of CaMKIIδincreases with the differentiation of osteoclasts .CaMKIIδmay play a key role in the osteoclastogenesis .