(A) Representative current traces measured in Xenopus oocytes in response to superfusion with 300 µM glutamate plus 100 µM cyclo-thiacide. All currents were measured at −70 mV. Vertical scale-bar, 0,5 µA; horizontal bar, 4 s. (B) GluA1 current amplitudes in oocytes expressing GluA1, or combinations of GluA1 with SGK3, the inactive form of PIKfyve (PIKfyve(S318A)), or wild type PIKfyve. Numbers of oocytes are n = 20–30. Significant changes (p<0.001) are indicated by *** (p = 0.00049; 0.00036; 0.000073, respectively). (C) Representative samples including controls from uninjected oocytes were biotinylated to isolate plasma membrane GluA1, then separated on an SDS gel, Western-blotted and probed with a primary rabbit anti-GluA1 antibody. The GluA1 protein has an apparent molecular weight of ∼105 kDa. (D) Bar graph showing relative abundance of GluA1 plasma membrane protein. The band intensity was quantified by densitometric analysis using the software Scion image.