FIG. 2.

The effect of Pairbp1 siRNA treatment on the expression and localization of PAIRBP1 and PGRMC1 in SIGCs. Compared to scramble (control) siRNA treatment, Pairbp1 siRNA selectively depleted PAIRBP1 protein as assessed by immunocytochemistry (A) and mRNA as measured by real-time PCR (B) without altering Pgrmc1 mRNA or localization in SIGCs maintained in serum-supplemented medium. In C the effect of Pairbp1 siRNA on the ability of progesterone (P4) to suppress SIGC apoptosis induced by serum withdrawal is shown. In B and C, values are expressed as a mean ± one standard error, with * indicating a value that is significantly different from scramble control (P < 0.05). The capacity of SIGCs treated with either scramble or Pairbp1 (D) siRNA and maintained in serum-supplemented medium to specifically bind ³H-P4 is shown. Values represent the mean ± one standard error for each dose of ³H-P4. Data was fitted using a single-binding-site model and represented by either a solid (scramble control) or dashed (PAIRBP1 siRNA) line.