Regulation of TMPRSS6 mRNA expression in response to BMP6. Hep3B cells were treated with 25 ng/mL of BMP6 for several time points between 1 and 48 hours (A), and were analyzed for hepcidin and TMPRSS6 relative to RPL19 mRNA expression by quantitative real-time RT-PCR. (B-C) Hep3B cells received 10 μg/mL of cycloheximide (B) or 60nM of LDN-193189 (C) before BMP6 (25 ng/mL) treatment and were analyzed for gene expression relative to RPL19 mRNA expression by quantitative real-time RT-PCR. The mean of 6 (A-B) and 3 (C) independent experiments is presented. (B-C) Results are reported as the mean ± SEM for the fold change from mock (just before adding BMP6) and significant changes represent the comparisons with mock. Significant changes are as follows: *P < .05; **P < .01; and ***P < .005.