Figure 5.

KAR non-canonical signalling induces internalization of KARs. (A) Myc-tagged GluR5-2b expressed in SHSY5-Y neuroblastoma was biotinylated before exposure to PdBu (1 μM) or kainate (300 μM) for 3 min. As a control, basal internalization was estimated at 4 and 37°C. Soluble and membrane fractions were separated, immunoprecipitated with streptavidin, immunoblotted, and probed with the myc antiserum. Fractional internalization was calculated by taking the sum of the signals present in plasma membrane (surface, Surf) and soluble fractions (internalized, Int) as 100%. In one set of experiments, cells were exposed for 3 h to pertussis toxin (0.5 μg/ml), before running the assay. (B) Summary of experimental data (n=4–11). ^**P<0.01; Student's t-test.