FIGURE 8.

Characterization of PAO. A, schematic presentation of MTF1 and cysteine residues. B, induction of Mt1 by PAO and arsenic. Hepa1c1c7 cells were treated with tBHQ at 30 μm, PAO at 0.01, 0.05, 0.1, 0.5, 1, or 5 μm, or arsenic at 1, 5, or 10 μm for 5 h. Total RNA was blotted for Mt1 and actin mRNA expression. C, direct binding of arsenic and PAO to the thiol groups of MT1. Purified MT1 protein was incubated with arsenic or PAO for 30 min; the mixture was precipitated with trichloroacetic acid, and free thiol groups were measured by using Ellman reagent with absorbance at 412 nm.