Modulation of miR-204 Expression during Chondrogenesis

Abstract

RUNX2 and SOX9 are two pivotal transcriptional regulators of chondrogenesis. It has been demonstrated that RUNX2 and SOX9 physically interact; RUNX2 transactivation may be inhibited by SOX9. In addition, RUNX2 exerts reciprocal inhibition on SOX9 transactivity. Epigenetic control of gene expression plays a major role in the alternative differentiation fates of stem cells; in particular, it has been reported that SOX9 can promote the expression of miRNA (miR)-204. Our aim was therefore to investigate the miR-204-5p role during chondrogenesis and to identify the relationship between this miR and the transcription factors plus downstream genes involved in chondrogenic commitment and differentiation. To evaluate the role of miR-204 in chondrogenesis, we performed in vitro transfection experiments by using Mesenchymal Stem Cells (MSCs). We also evaluated miR-204-5p expression in zebrafish models (adults and larvae). By silencing miR-204 during the early differentiation phase, we observed the upregulation of SOX9 and chondrogenic related genes compared to controls. In addition, we observed the upregulation of COL1A1 (a RUNX2 downstream gene), whereas RUNX2 expression of RUNX2 was slightly affected compared to controls. However, RUNX2 protein levels increased in miR-204-silenced cells. The positive effects of miR204 silencing on osteogenic differentiation were also observed in the intermediate phase of osteogenic differentiation. On the contrary, chondrocytes’ maturation was considerably affected by miR-204 downregulation. In conclusion, our results suggest that miR-204 negatively regulates the osteochondrogenic commitment of MSCs, while it positively regulates chondrocytes’ maturation.

Expression of FBXW11 in normal and disease‐associated osteogenic cells

“…differentiation. 17 Thus, by transfecting cells with anti-miR 204 we did not observe FBXW11 and RUNX2 modulation after 3 days of osteogenic differentiation (Figure 3D). However, forced expression of RUNX2 after 7 and 14 days of osteogenic differentiation, obtained by transfecting MSCs with anti-miR204, resulted in increased FBXW11 expression after 7 days (Figure 3E).…”

“…16 RUNX2 can also be regulated post-transcriptionally and we recently demonstrated that RUNX2 protein levels are increased in miR-204-silenced MSCs during the middle phase of osteogenic differentiation. 17 Moreover, using melanoma cells KO for the RUNT domain of RUNX2, we demonstrated that the RUNT domain plays an important role in the modulation of the expression of genes involved in bone metastases. 18 The present work, therefore, contributes to the understanding of FBXW11 role in osteogenic cells by evaluating its modulation both during osteogenic commitment and in altered osteoblastic cells characterized by RUNX2 mutations or resulting from tumour transformation.…”

“…In particular, the WNT/β‐catenin pathway induces RUNX2 expression during osteogenic commitment 16 . RUNX2 can also be regulated post‐transcriptionally and we recently demonstrated that RUNX2 protein levels are increased in miR‐204‐silenced MSCs during the middle phase of osteogenic differentiation 17 . Moreover, using melanoma cells KO for the RUNT domain of RUNX2, we demonstrated that the RUNT domain plays an important role in the modulation of the expression of genes involved in bone metastases 18 …”

miR-30a inhibits the osteogenic differentiation of the tibia-derived MSCs in congenital pseudarthrosis via targeting HOXD8

“…miRNAs are involved in osteogenic differentiation [ 25 , 26 ]. miR-22 could induce the osteogenic differentiation of valvular interstitial cells by downregulation of CAB39 during aortic valve calcification [ 27 ].…”

The cell developmental atlas of human embryonic temporomandibular joint

“…RUNX2 was highly expressed along the differentiation pathway of TSCs to hypertrophic chondrocytes and TSCs to osteoblasts. SOX9 was reported to be a pivotal transcriptional regulator of chondrogenesis 22 . MMP13 was related to the osteogenesis 23 .…”