Figure 4.

TS:YSOG3-PKMζ is upregulated and localizes to synapses after forskolin and rolipram cLTP. A, Schematic indicating how neurons expressing PKMζ-YFP were stimulated and visualized over 10 h. B, Stimulation increased PKMζ synthesis and accumulation; unstimulated neurons showed no change in YFP signal. Scale bars, 20 μm. C, Fluorescence quantification of dendritic spines indicates that there was more PKMζ in spines after stimulation. ***p < 0.001 (unpaired two-tailed Student's t test). n = 41 stimulated spines; n = 40 unstimulated spines. Error bars indicate SEM. D, Schematic indicating how neurons transfected with TS:YSOG3-PKMζ were treated with BILN for 24 h and then imaged. E, Transfected neurons stimulated with forskolin and rolipram, left unstimulated, or left without BILN were fixed and immunolabeled for PSD95. TS:YSOG3-PKMζ YFP fluorescence (green pseudocolor in magnified images) and PSD95 immunofluorescence (red pseudocolor) were imaged. Stimulated neurons show increased YFP fluorescence and TS:YSOG3-PKMζ colocalization with PSD95 (yellow pseudocolor). Scale bars: whole cell, 20 μm; magnified pseudocolor, 2 μm.