[Corrigendum] MicroRNA‑1 promotes cartilage matrix synthesis and regulates chondrocyte differentiation via post‑​transcriptional suppression of Ihh expression  

Figure 1.

miR-1 promotes the proliferation of mouse thorax chondrocytes. (A) Expression of Col-I in mouse thorax chondrocytes was assessed using immunofluorescence staining. Mouse fibroblasts were used as the positive control for Col-I staining; magnification, ×40; scale bars, 40 µm. (B) RT-qPCR results showed that transfection of the miR-1 mimic (40 pM) increased miR-1 levels, whereas transfection of the anti-miR-1 decreased its expression, compared with the transfection of a negative control mimic (ConmiR) or a control miRNA inhibitor (Control) in the mouse sterna chondrocytes at 24 h post-transfection. n=3 for each group; *P<0.05 vs. ConmiR or Control. (C and D) Cell growth was measured by EdU cell proliferation staining 48 h after mouse sterna chondrocytes were transfected with the miR-1 mimic (miR-1) or negative control mimic (ConmiR), and miR-1 inhibitor (anti-miR-1) or a control miRNA inhibitor (Control) at 120 nM, respectively; (C) images show the staining for EdU and DAPI, and (D) bar graph data summarizes the percentage of EdU-proliferating cells in 5 view fields per group; miR-1 stimulates chondrocyte proliferation. Scale bars, 40 µm; *P<0.05 vs. ConmiR; #P<0.05 vs. Control. (E) Transfection of miR-1 enhanced mouse thorax chondrocyte proliferation, while transfection of anti-miR-1 inhibited proliferation, as measured by the CCK-8 cell proliferation assay. n=5 for each group; *P<0.05 vs. ConmiR or Control. (F) miR-1 increased Sox-9 mRNA levels, a marker for chondrocyte proliferation. Sox-9 mRNA levels in mouse sterna chondrocytes transfected with the miR-1 mimic (miR-1), or control miRNA mimic (conmiR), and inhibitor (anti-miR-1) or control miRNA inhibitor (Control) were quantified by RT-qPCR at 24 h post transfection. n=3 for each group; *P<0.05 vs. ConmiR; #P<0.05 vs. Control. Col, collagen; Sox9, SRY-box transcription factor 9; RT-qPCR, reverse transcription-quantitative PCR; miR/miRNA, microRNA.