Immunoprecipitation of GFP-KIF13A-ST and effect of phosphatase inhibitors on centaurin-α1 coprecipitation. (A) GFP-immunoprecipitation from protein extracts of 7–10 DIV organotypic hippocampal slices expressing GFP-KIF13A-ST protein, or GFP as control, as described for Fig. 4 A of the main text. The immunoprecipitation of the recombinant protein was detected by Western blot with an anti-GFP antibody. GFP-KIF13A-ST appears as multiple bands, probably due to proteolytic degradation. Arrowhead indicates full-length recombinant protein; asterisks indicate light and heavy chains of the IgG used for immunoprecipitation. (B) Representative Western blots from experiments similar to Fig. 4 B of the main text but in the presence (+inhibitors) or absence (−inhibitors) of phosphatase inhibitors in the homogenization buffer. Nonimmune rabbit IgGs were used as immunoprecipitation control. GluA1, centaurin-α1, and pGluA1 (S845) were detected by Western blot. (C) Quantification of the amount of pGluA1 (S845) immunoprecipitated in both conditions (black circles, with phosphatase inhibitors; red squares, without phosphatase inhibitors). Darker lines represent the mean ± SEM, while lighter lines show individual values for each experiment. n = 4 experiments. (D) Quantification of the amount of centaurin-α1 protein coprecipitated in both conditions (black circles, with phosphatase inhibitors; red squares, without phosphatase inhibitors) and normalized to baseline coprecipitated protein. Darker lines represent the mean ± SEM, while lighter lines show individual values for each experiment. n = 4 experiments.