A Systems’ Biology Approach to Study MicroRNA-Mediated Gene Regulatory Networks
Figure 2
Model calibration and validation. (a) Model calibration. The figures show the relative change of the p21 mRNA and protein expression levels after overexpression of the indicated miRNAs (Model: model simulation; Data: experimental data). These data were normalized to the control group in which the p21 mRNA and protein expression levels were measured when the miRNAs were normally expressed (a.u.: arbitrary unit). (b) Experimental workflow. In the experiments, Sk-Mel-147 cells were seeded in six well plates. Then, mature miRNA mimics were transfected individually at a concentration of 100 nM (miR-572 and miR-93) or in combination at 50 nM each (miR-572 + miR-93). After 48 hr transfection with miRNA mimics, the cells were pulse treated with 250 nM doxorubicin for 1 hour after which normal growth medium was replenished. The immunblotting were performed to measure p21 expression at 0, 2, 4, 6, 8 and 24 hr post-doxorubicin treatment. (c) Temporal dynamics of p21 transcriptional function. Afterdoxorubicin treatment, the expression of p53, a TF of p21, was measured using immunblotting and these data were used to characterize the transcriptional function of p21 using MATLAB linear interpolation function. (d) Model validation. We measured the expression of p21 protein in response to genotoxic stress in the four scenarios as described in the main text. The measured data (Data) were compared with the model simulations (Model). The figures (a), (c) and (d) are adapted from our previous publication [4].
