Figure 1. Pannexins are N-glycosylated but not O-glycosylated as defined by sensitivity to enzymatic digestion. Upon treatment of total protein lysates from HEK-293T cells ectopically expressing Panx1, 2, or 3 with PNGase F, a significant gel mobility shift in western blots was observed for Panx1 (A) and Panx3 (C) with a moderate change in mobility for Panx2 (B), indicating that all 3 pannexins are N-glycosylated. Sequential treatments with sialidase A and O-glycanase resulted in a change in the banding pattern of Fetuin in a Sypro-stained gel, used as a positive control (D), but did not generate visible banding shifts in any of the pannexin labeled blots (A, B, and C). The position of molecular weight standards are shown in kDa.