FIGURE 6.

Actn4 knockdown does not impair group 1 mGluR expression, signaling, or basal excitatory transmission. A, representative immunoblots (IB) of mGlu₁ or mGlu₅ from biotin-labeled (surface; mGlu₁, 850 μg; mGlu₅, 450 μg input lysate) or total lysates (30 μg) of cortical neurons treated with control or Actn4 siRNA. Arrows point to bands corresponding to the receptor dimer and monomer. B, quantification from images like those in A of the mGlu₁ (left panel) and mGlu₅ (right panel) surface/total ratio in control or Actn4 siRNA-treated neurons. Means ± S.E.; n = 4 experiments; p > 0.05. ns, not significant. C, Actn4 knockdown does not impair DHPG-induced ERK-MAPK activation. Shown are representative immunoblots of DIV 12 cortical neuron extracts probed with anti-phospho-ERK1/2(Thr-202/Tyr-204) and anti-ERK1/2. D, quantification of ERK2 phosphorylation expressed as the ratio to total ERK2 from images like those shown in C. n = 3 independent experiments; *, p < 0.05, **, p < 0.01. E, representative mEPSC traces (top panel) and summary data (bottom panel) showing that Actn4 knockdown does not affect basal AMPA receptor-mediated transmission in hippocampal neurons (DIV 12/13) treated with control or Actn4 siRNA. n = 3 independent experiments; control siRNA, n = 18 cells; Actn4 siRNA, n = 23 cells. Calibration bar = 30 pA, 300 ms.