Tax inhibits SG formation and augments arsenite-induced apoptosis. (A) 293T cells were treated with 0.5 mM of sodium arsenite for 60 minutes and then were stained with anti-USP10 antibodies (green), anti-G3BP1 antibodies (red), and Hoechst33258 (blue). The bar indicates 20 μm. (B) 293T cells were transfected with the indicated plasmids (Tax, Tax^62-353, TaxSH-1, or TaxSH-2). The transfected cells were treated with 0.5 mM of sodium arsenite for 60 minutes and then were stained with anti-USP10 antibodies (green), anti-Tax (red) antibodies, and Hoechst33258 (blue). The arrow indicates a cell that exhibits reduced SG formation. The bar indicates 20 μm. (C,D) The SG (%) in Tax-positive cells and control cells is presented. (E) The number of cells containing condensed nuclei among the Tax-positive cells was counted. (F) 293T cells were transfected with Tax plasmids and then were incubated with or without 5 mM of NAC, treated with 0.5 mM of sodium arsenite, and stained with anti-Tax antibodies and Hoechst33258. The numbers of cells containing condensed nuclei among the Tax-positive cells and the control cells were counted. In all experiments, the values denote mean ± SD; *P < .05; **P < .01; ***P < .001; NS indicates not statistically significant.