Photomicrographs were obtained using an Olympus DSU IX-81 inverted microscope fitted with a spinning disk confocal attachment and a 60x/1.2 N.A. water immersion objective. EGFP labeled neurons were chosen randomly for imaging from neuronal cultures from three coverslips. For all dendritic spine analyses, the region of the apical dendrites after the first branch point was selected (secondary dendrite). Dendritic spine density was scored from three randomly chosen areas per neuron. Z-sections were taken at 0.3-μm intervals and were stacked with maximum projection. All analyses were conducted blind to genotype. Data were expressed as means ± SEM from independent replicates.
