A. TSFs isolated from PND21 or adult striatum were immunoblotted for spinophilin, PP1 catalytic subunit (PP1c), CaMKIIβ, CaMKIIα, or PSD-95. B. Spinophilin was immunoprecipitated from TSFs isolated from PND21 (P21) or adult animals. Precipitates were immunoblotted for spinophilin, PP1c, CaMKIIβ, or CaMKIIα. C. Striatal TSFs from PND21 or adult mice were immunoblotted for phospho-Thr286/7 and total CaMKII. Phospho-Thr286/7 immunoreactivity was normalized to total CaMKIIβ or CaMKIIα levels, respectively. All values were normalized to the mean at PND21, and then expressed as the mean±S.E.M from analyses of the indicated number of animals. * P<0.05, **P<0.01, ***P<0.001.