ABCC8 and pancreatic insulinoma: To obtain a structure of KATP channels bound to GBC and ATP, channels comprising a rat Kir6.2 and FLAG-tagged hamster SUR1 (96% and 95% sequence identity to human sequences, respectively) were expressed in rat insulinoma INS-1 832/13 cells (Hohmeier et al., 2000), affinity purified, and imaged in the presence of 1 mM ATP (no Mg2+) and 1 μM GBC, as described previously (Martin et al., 2017).