[Preliminary study on microRNA regulated osteogenic and chondrogenic differentiation of mouse stem cells]

To investigate the specific microRNA (miRNA) in osteogenic and chondrogenic differentiations of C3H10Tl/2 cells.

C3H10Tl/2 cells were induced to differentiate into osteoblasts and chondrocytes. Specific miRNA more than 2 fold change and 2 average normalized probe signal between C3H10Tl/2 and C3H10Tl/2-derived osteoblast, and' between C3Hl0Tl/2 and C3H10Tl/2-derived chondrocytes were screened out by miRNA microarray, and verified by real-time fluorescence quantitative PCR (RT-qPCR).

Alkaline phosphatase expression of osteogenic induced group was significantly higher than that of control group at 7 days after induced (P < 0.05). RT-qPCR results showed the expressions of Runx2, serine protease (Sp7), collagen type I, and osteopontin (OPN) genes were significantly increased at 7, 14, and 21 days after induced when compared with before induced (P < 0.05). Western blot results showed the expressions of Runx2, Sp7, collagen type I, and OPN proteins of osteogenic induced group were significantly higher than those of control group at 21 days after induced (P < 0.05). The expressions of SOX9, collagen type II, Aggrecan, and Has2 were significantly increased at 5, 10, and 15 days after induced when compared with before induced (P < 0.05). The expressions of SOX9, collagen type 2, Aggrecan, and Has2 proteins of chondrogenic induced group were significantly higher than those of control group at 15 days after induced (P < 0.05). Totally, 10 osteogenic and 3 chondrogenic miRNA more than 2 fold change and 2 average normalized probe signal were screened out by miRNA microarray. RT-qPCR results of these specific miRNAs were similar to microarray results except miR-455-3p.

Specific miRNAs are screened out by microarray and it is a good foundation for the future study on miRNA functional verification and target gene prediction.