FIGURE 7.

Effect of down-regulation and up-regulation of SULT1A3 on dopamine toxicity. A, effect of three siRNA sequences on the expression of SULT1A1/3 protein. SK-N-MC cells were treated with 10 nm siRNA for 72 h, and SULT1A1/3 protein levels were measured by Western blotting. B, dose-response curve of the effect of siRNA-B on dopamine toxicity. SK-N-MC cells were treated with siRNA for 48 h and then increasing concentrations of dopamine for 24 h following which cell viability was determined. C, dose-response curve of the effect of siRNA-C on dopamine toxicity. SK-N-MC cells were treated with siRNA for 48 h and then increasing concentrations of dopamine for 24 h following which cell viability was determined. D, dose-response curve of the effect of siRNA-C on dopamine toxicity in SH-SY5Y cells. Cells were treated with siRNA for 48 h and then increasing concentrations of dopamine for 24 h following which cell viability was determined. E, expression of SULT1A3 in murine Neuro 2A cells was determined. Cells were transfected with empty vector or a FLAG-SULT1A3 construct, and cell lysates were collected up to 96 h for Western blot analysis. F, dose-response curve of the effect of SULT1A3 expression on dopamine toxicity in Neuro 2A cells. Cells were transfected for 48 h and then treated with increasing concentrations of dopamine for 24 h following which cell viability was determined. Error bars, S.E.