Fig. 5. Essential role of syntaxin 1A in KA-promoted EAAC1 internalization. (A) Representative immunoblot and quantitative analysis showing that stimulation with 10 µM KA causes a decrease in EAAC1 surface expression in C6 glioma cells, which is rescued by transfection of K44A dynamin. ^*P<0.05, ^**P<0.01 compared with the cells without KA stimulation (n=3). (B) Stimulation with KA for 30 minutes inhibits the EAAC1-mediated glutamate transport in C6 glioma cells (upper panel), which is correlated with a decrease in the surface expression of EAAC1 (lower panel). ^**P<0.01 versus the cells without KA stimulation (n=3). (C) Representative immunoblot and quantitative analysis of internalized EAAC1 upon KA stimulation for various time show constitutive internalization of EAAC1, and that KA stimulation significantly promotes EAAC1 internalization in C6 glioma cells. ^**P<0.01 compared with cells without KA stimulation at identical time points (n=4). (D) Representative immunoblot of surface EAAC1 expression upon KA stimulation for various time showing that Syn1A siRNA rescues KA-induced reduction in EAAC1 surface expression in C6 glioma cells. (E) Representative immunoblot of internalized EAAC1 upon KA stimulation for various time showing that Syn1A siRNA abolishes the KA-promoted EAAC1 internalization in C6 glioma cells.