Western blot analysis of SR proteins after stimulation by TGF-β
. (A) HFL-1 cells were stimulated with TGF-β1 (10 ng/mL) for 6, 24, and 48 h. Cell homogenates were separated by SDS-PAGE and after blotting the proteins were detected with an antibody that recognizes a phospho-epitope on a wide range of SR proteins. Bands were visualized by a fluorescent secondary antibody and analyzed on Odyssey® FC imaging system. The most prominent bands represent the splicing factors SRp75, SRp55, SRp40, SRp30a-c, and SRp20. #The band migrating around 30-kDa could consists of several splicing factors with the approximate molecular weight of 30 kDa. (B) Bands were quantified by densitometry and were then related to their respective GAPDH loading control. Values show the relative expression between TGF-β1-stimulated cells compared to untreated. (C) The expression of SRp20 at 6, 24, and 48 h was examined by western blot and bands were quantified with densitometry. The antibody is not directed against phospho-epitope of the protein. Presented values are the intensity of each band relative to the intensity of the loading control: GAPDH. Each value represent mean and SEM from four individual experiments. *P < 0.05.