The protein level of COL4A1 was determined by using Western blot. After the cells were transfected with ASO-miR-214-5p, ASO-NC, miR-214-5p mimic and its control, and pcDNA3.1 (+)-COL4A1 and its control, for 48 hours, the cells were homogenised in radioimmunoprecipitation assay (
RIPA) buffer (Beyotime, Shanghai, China) and additionally, protease inhibitors. Protein concentrations were determined by a bicinchoninic acid (
BCA) assay kit (Thermo Fisher Scientific Inc., Rockford, Illinois). Equivalent amounts of protein (10 μg) were separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE), and were then transferred to
nitrocellulose membranes (Sigma-Aldrich). After blocking with 5% non-fat milk, the membranes were incubated with anti-COL4A1 antibody (
ab6586; 1:1000; Abcam, Cambridge, Massachusetts) at 4°C overnight. GAPDH was used as a loading control. Subsequently, the membranes were washed with Tris-buffered saline with Tween 20 (TBST) and incubated with horseradish peroxidase (HRP)-conjugated anti-goat IgG (
ab181658; 1:5000; Abcam) at room temperature for two hours. An enhanced chemiluminescence (ECL) system was used to visualise the bands. Quantitative analysis was conducted by
Bio-Rad Quantity One 1-D Analysis Software (Bio-Rad Laboratories, Hercules, California).
Li Q.S., Meng F.Y., Zhao Y.H., Jin C.L., Tian J, & Yi X.J. (2017). Inhibition of microRNA-214-5p promotes cell survival and extracellular matrix formation by targeting collagen type IV alpha 1 in osteoblastic MC3T3-E1 cells. Bone & Joint Research, 6(8), 464-471.