Expression of specific gene markers. The RT-PCR analysis was performed using RNA isolated from mononucleated and MC3T3-E1 cells before and after differentiation into osteoblast and osteoclast cells. (i) The expression of Opn (234 bp) indicates differentiation into mature osteoblasts. (ii) CatK (350 bp) expression shows osteoclast differentiation. (iii) The activation of Sca-1 (167 bp) is indicative of the degree of stemness of the cells. (iv) Gapdh (717 bp) was used as a positive control. (v) The labelled 100 bp DNA marker to identify the approximate size of amplicons. Equal volumes of the products were separated in agarose gels using 100 bp DNA markers and stained with ethidium bromide.