FIGURE 2.

Trafficking of Panx1 and Panx3 was disrupted in the presence of a dominant-negative Sar1 mutant. BICR-M1R_k cells expressing Panx1 or Panx3 together with Sar1^WT or Sar1^H79G were immunolabeled for Panx1 (A) or Panx3 (B). Both Panx1 and Panx3 were capable of trafficking and localizing to the cell surface in the presence of Sar1^WT (A and B, filled arrows). Expression of Sar1^H79G resulted in Panx1 and Panx3 being retained in an ER-like compartment (A and B, arrowheads); however, when cells expressed Panx1 or Panx3 without expressing Sar1^H79G in the same cellular environment, both Panx1 and Panx3 trafficked to the plasma membrane (A and B, insets, arrows). Western blotting of Panx1 and Panx3 in the presence of Sar1^H79G (C) or after long term BFA treatment (19 h) (D) revealed an accumulation of the high mannose species of Panx1 and Panx3, with a noticeable reduction in the higher molecular weight glycosylation species (C and D). Nuclei are stained with Hoechst 33342 (blue). Bars, 10 μm. Results shown are representative of three independent experiments.