Fig. 1

circZNF609 is downregulated in TGF-β1-induced activated fibroblasts and fibrotic lung tissues from silica-inhaled mice. A The protein levels of fibronectin, collagen I, vimentin, and α-SMA in each group were examined by the western blot. The results of the experiment were repeated at least three times. B The RNA expression of α-SMA and circZNF609 in MRC-5 cells using qRT-PCR analysis; GAPDH was used as the internal reference. C Fluorescence in situ hybridization (FISH) assay was conducted to detect the expression of circZNF609 in control and TGF-β1-treated groups. D Pathological changes in mouse lung tissues were presented by H&E staining, and the arrow pointed to the representative fibrosis foci (n = 6 for each group). E Hydroxyproline content of the lung tissues was used to examine the degree of collagen deposition. F qRT-PCR analysis of circZfP609 expression in mouse fibrotic lung tissues on days 7, 14, and 28 (n = 6 for each group). All data were expressed as the means ± SD of at least 3 independent experiments, *p < 0.05 and **p < 0.01