IL-13 induces α-SMA expression through YY1.

<p>(A) The α-SMA luciferase reporter (α-SMA-Luc, 5 μg) along with a 2.5 μg of control vector or 2.5 μg of YY1 was transiently transfected by electroporation into MRC-5 cells. At 24 h after transfection, IL-13 (30 ng/ml) or PBS were used to treat the MRC-5 cells for 24 h. These cells were lyzed with luciferase lysis buffer. Relative light units (RLU) were measured with a luminometer. The data are presented with standard errors derived from at least three independent experiments, mean ± SEM. <i>**P</i> < 0.01. (B) LL97A cells were infected with μl of control lentivirus vector shRNA (1x10⁵) or 10μl of lentivirus vector YY1 shRNA (1x10⁵) for 2 days. Lentiviral particles were produced as described in our previous paper [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119039#pone.0119039.ref023" target="_blank">23</a>]. Puromycin (4 μg/ml) was then used to select the transduced cells, which were stimulated by IL-13 (30 ng/ml) for 24 h. The selected LL97A cells were immunostained with anti-α-SMA (green) and anti-YY1 (red) antibodies. Representative pictures are presented at the original magnification shown a ruler on image. Representative examples are from three independent experiments. (C) The levels of YY1 and α-SMA in LL97A cells transduced and stimulated with IL-13 (30 ng/ml) were determined by western blot using corresponding antibodies. (D) Densitometry of western blot from 2C is measured by ImageJ. ** indicated p≤0.01.