Figure 4.

SAP-dependent Mkl1 target genes are mechanoresponsive. (A) Effect of static (20%) and cyclic (15%, 0.3 Hz) strain on Tnc and c-fos mRNA levels. HC11 cells were cultured on either growth factor reduced matrigel matrix- or fibronectin-coated silicone membranes in 0.03% serum-containing medium for 24 h before applying static or cyclic strain for 1 h. Cells cultured under the same conditions and not exposed to mechanical stimulation were used as a resting control. The two types of coating gave identical results under the indicated experimental conditions. Total RNA was extracted and qRT-PCR was performed for Tnc and c-fos mRNA levels. Values normalized to Gapdh are expressed relative to the values of resting cells. Data represent means ± SD from three independent experiments. Significant differences to the resting control, ***P < 0.001, **P < 0.01, *P < 0.05. (B) SAP-dependent genes respond to cyclic strain. HC11 cells were stretched and mRNA analyses were performed as described in (A). Data and statistical significance are expressed as in (A).