Figure 1

Spine changes induced by Stau1 siRNA are prevented by NMDA receptor blockade and high Mg²⁺. (A) Confocal images of representative YFP-expressing CA1 pyramidal cells (left) and apical dendrites (right) after co-transfection with siRNA-CTL or siRNA-STAU1 and maintained in normal or elevated Mg²⁺ (12 mM) to impair NMDAR function. (B) Spine density was reduced by high Mg²⁺ treatment but not with the NMDA receptor antagonist AP5 (100 μM), and was unchanged by Stau1 siRNA transfection. (C) Cumulative plots of the distribution of spine length for each condition, with summary bar graph of spine length in the inset, showing increased spine length in medium containing high Mg²⁺ or AP5. Spine length was increased after Stau1 siRNA transfection in normal medium but not in Mg²⁺ and AP5 treated slices. (D) Summary bar graph of number of regular, elongated and filopodia types of spines in each condition, showing decrease in regular and increase in elongated spines in high Mg²⁺ or AP5. Stau1 siRNA transfection decreased regular and increased elongated spines in normal medium but not in high Mg²⁺ or AP5, suggesting that Stau1 effects on spine shape are due to actions on endogenous NMDA receptor-mediated plasticity. Scale bars 25 μm, 5 μm. *, P < 0.05, t-test. Error bars represent s.e.m.